Nothing Special   »   [go: up one dir, main page]

You seem to have javascript disabled. Please note that many of the page functionalities won't work as expected without javascript enabled.
 
 
Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

Search Results (338)

Search Parameters:
Keywords = electronic tongue

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
16 pages, 2505 KiB  
Article
Novel Insights into the Enrichment Pattern of Aroma and Taste in Cooked Marinated Meat Products of Black Pork via Typical Process Steps
by Haitang Wang, Jiapeng Li, Yan Zhao, Qiang Li and Shouwei Wang
Foods 2024, 13(22), 3643; https://doi.org/10.3390/foods13223643 - 15 Nov 2024
Viewed by 78
Abstract
This study aims to reveal the evolution mechanism of odour and taste active compounds in cooked marinated pork knuckles via typical process steps; among them, the brine soup stage was the most important part due to spices’ enriching flavours. These results revealed that [...] Read more.
This study aims to reveal the evolution mechanism of odour and taste active compounds in cooked marinated pork knuckles via typical process steps; among them, the brine soup stage was the most important part due to spices’ enriching flavours. These results revealed that the content and diversity of volatile compounds increased due to the addition of spices and heating temperature, imparting a unique aroma. Aldehydes played the main role in the overall odour. Benzaldehyde, hexanal, 1-octen-3-ol, levulinic acid, hydroxyacetone, ethyl octanoate, and 2-pentyl-furan were identified as the most important odour-active compounds. The key taste-active amino acids were glutamine, leucine, valine, and lysine. The IMP, AMP, and GMP provided a strong umami taste. Taste nucleotides and Val, Leu, Ile, and Phe were important precursor substances for aldehydes. The high responses of the electronic nose indicated that the gas component contained alkanes, alcohols, and aldehydes. The synergistic effects between umami-free amino acids and nucleotides correlated well with umami, as assessed by the electronic tongue. These results could be a starting point for the manufacturing industry, contributing to a better understanding of product performance. Full article
Show Figures

Figure 1

Figure 1
<p>A manufacturing flowchart of cooked marinated pork knuckle.</p>
Full article ">Figure 2
<p>The changes in different groups of volatile compounds in cooked marinated pork knuckle during processing. The significant differences among different treatments are indicated by different uppercase letters (a–c) (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 3
<p>Variable importance projection (VIP) scores (<b>A</b>) and the heat map of volatile compounds (<b>B</b>) in cooked marinated pork knuckle during processing.</p>
Full article ">Figure 4
<p>Changes in taste-active amino acids (<b>A</b>), nucleotides contents (<b>B</b>), TAV of amino acids (<b>C</b>), and EUC of nucleotides (<b>D</b>) in cooked marinated pork knuckle during processing. The significant differences among different treatments are indicated by different uppercase letters (a–d) (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 5
<p>The sensor responses of the odour attributes of electronic nose (<b>A</b>), PCA analysis of electronic nose (<b>B</b>), the taste attributes of the electronic tongue (<b>C</b>), and PCA analysis of electronic tongue (<b>D</b>). The significant differences among different treatments are indicated by different uppercase letters (a–d) (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 6
<p>Heat map of the Pearson correlation between taste-active compounds and E-tongue.</p>
Full article ">
14 pages, 3701 KiB  
Article
Smart E-Tongue Based on Polypyrrole Sensor Array as Tool for Rapid Analysis of Coffees from Different Varieties
by Alvaro Arrieta Almario, Oriana Palma Calabokis and Eisa Arrieta Barrera
Foods 2024, 13(22), 3586; https://doi.org/10.3390/foods13223586 - 10 Nov 2024
Viewed by 449
Abstract
Due to the lucrative coffee market, this product is often subject to adulteration, as inferior or non-coffee materials or varieties are mixed in, negatively affecting its quality. Traditional sensory evaluations by expert tasters and chemical analysis methods, although effective, are time-consuming, costly, and [...] Read more.
Due to the lucrative coffee market, this product is often subject to adulteration, as inferior or non-coffee materials or varieties are mixed in, negatively affecting its quality. Traditional sensory evaluations by expert tasters and chemical analysis methods, although effective, are time-consuming, costly, and require skilled personnel. The aim of this work was to evaluate the capacity of a smart electronic tongue (e-tongue) based on a polypyrrole sensor array as a tool for the rapid analysis of coffees elaborated from beans of different varieties. The smart e-tongue device was developed with a polypyrrole-based voltammetric sensor array and portable multi-potentiostat operated via smartphone. The sensor array comprised seven electrodes, each doped with distinct counterions to enhance cross-selectivity. The smart e-tongue was tested on five Arabica coffee varieties (Typica, Bourbon, Maragogype, Tabi, and Caturra). The resulting voltammetric signals were analyzed using principal component analysis assisted by neural networks (PCNN) and cluster analysis (CA), enabling clear discrimination among the coffee samples. The results demonstrate that the polypyrrole sensors can generate distinct electrochemical patterns, serving as “fingerprints” for each coffee variety. This study highlights the potential of polypyrrole-based smart e-tongues as a rapid, cost-effective, and portable alternative for coffee quality assessment and adulteration detection, with broader applications in the food and beverage industry. Full article
Show Figures

Figure 1

Figure 1
<p>Scheme of functional analogy between the human taste system and an e-tongue and its parts (sample; sensory array; multi-channel system; and pattern recognition system).</p>
Full article ">Figure 2
<p>Chemical structure of doping ions used in the preparation of the PPy sensor array.</p>
Full article ">Figure 3
<p>Image of the smart e-tongue device and its parts (sensor array, multi-potentiostat, and data recording and processing system).</p>
Full article ">Figure 4
<p>Schematic of oxidation/reduction processes in PPy sensors where cation exchange (process I) and anion exchange (process II) are presented.</p>
Full article ">Figure 5
<p>Reproducibility of (<b>a</b>) the voltammetric signals of 50 cycles of the S7 sensor (PPy/TSA) against a coffee sample from Maragogype variety beans and (<b>b</b>) Voltammetric signals recorded by different S5 sensors (PPy/DBS) in replicates of Typica variety bean coffee prepared in different batches. The lines represent all the replicates of the voltammetric signals of each sensor.</p>
Full article ">Figure 6
<p>Voltammetric signals recorded by the sensor array against a coffee sample prepared with Caturra variety beans as instance of sensor redox response variability that contributes to cross-selectivity.</p>
Full article ">Figure 7
<p>Voltammetric signals of the lithium perchlorate/S1 doped sensor (PPy/PC) versus coffee samples prepared with beans of different varieties as instance of response variability and cross-selectivity.</p>
Full article ">Figure 8
<p>Loading graph resulting from PCNN analysis on the data matrix recorded with the smart e-tongue on the analyzed coffee samples: red-S1 (PPyPC); purple-S2 (PPyFCN); green-S3 (PPy/SF); fuchsia-S4 (PPy/SO4); yellow-S5 (PPy/DBS); grey-S6 (PPy/AQDS); and blue-S7 (PPy/TSA).</p>
Full article ">Figure 9
<p>Score graph resulting from the PCNN analysis on the data matrix recorded with the smart e-tongue on the analyzed coffee samples.</p>
Full article ">Figure 10
<p>Dendrogram of cluster analysis for coffee samples elaborated with beans of different varieties.</p>
Full article ">
14 pages, 3409 KiB  
Article
Detection of Apple Sucrose Concentration Based on Fluorescence Hyperspectral Image System and Machine Learning
by Chunyi Zhan, Hongyi Mao, Rongsheng Fan, Tanggui He, Rui Qing, Wenliang Zhang, Yi Lin, Kunyu Li, Lei Wang, Tie’en Xia, Youli Wu and Zhiliang Kang
Foods 2024, 13(22), 3547; https://doi.org/10.3390/foods13223547 - 6 Nov 2024
Viewed by 464
Abstract
China ranks first in apple production worldwide, making the assessment of apple quality a critical factor in agriculture. Sucrose concentration (SC) is a key factor influencing the flavor and ripeness of apples, serving as an important quality indicator. Nondestructive SC detection has significant [...] Read more.
China ranks first in apple production worldwide, making the assessment of apple quality a critical factor in agriculture. Sucrose concentration (SC) is a key factor influencing the flavor and ripeness of apples, serving as an important quality indicator. Nondestructive SC detection has significant practical value. Currently, SC is mainly measured using handheld refractometers, hydrometers, electronic tongues, and saccharimeter analyses, which are not only time-consuming and labor-intensive but also destructive to the sample. Therefore, a rapid nondestructive method is essential. The fluorescence hyperspectral imaging system (FHIS) is a tool for nondestructive detection. Upon excitation by the fluorescent light source, apples displayed distinct fluorescence characteristics within the 440–530 nm and 680–780 nm wavelength ranges, enabling the FHIS to detect SC. This study used FHIS combined with machine learning (ML) to predict SC at the apple’s equatorial position. Primary features were extracted using variable importance projection (VIP), the successive projection algorithm (SPA), and extreme gradient boosting (XGBoost). Secondary feature extraction was also conducted. Models like gradient boosting decision tree (GBDT), random forest (RF), and LightGBM were used to predict SC. VN-SPA + VIP-LightGBM achieved the highest accuracy, with Rp2, RMSEp, and RPD reaching 0.9074, 0.4656, and 3.2877, respectively. These results underscore the efficacy of FHIS in predicting apple SC, highlighting its potential for application in nondestructive quality assessment within the agricultural sector. Full article
Show Figures

Figure 1

Figure 1
<p>China’s apple production in the last ten years.</p>
Full article ">Figure 2
<p>FHIS: (<b>a</b>) data acquisition platform; (<b>b</b>) the schematic diagram.</p>
Full article ">Figure 3
<p>Spectral curve acquisition: (<b>a</b>) ROI extraction; (<b>b</b>) the original fluorescence hyperspectral curve.</p>
Full article ">Figure 4
<p>The spectra after different preprocessing methods: (<b>a</b>) SNV, (<b>b</b>) SG, (<b>c</b>) WT, (<b>d</b>) VN.</p>
Full article ">Figure 5
<p>Distribution of variables after primary feature extraction: (<b>a</b>) VIP, (<b>b</b>) SPA, (<b>c</b>) XGBoost.</p>
Full article ">Figure 6
<p>Distribution of variables after secondary feature extraction: (<b>a</b>) VIP + XGBoost, (<b>b</b>) SPA + VIP, (<b>c</b>) SPA + XGBoost.</p>
Full article ">Figure 7
<p>The plot of predictive fit of the three best regression models: (<b>a</b>) SPA + VIP-GBDT, (<b>b</b>) VIP + XGBoost-RF, (<b>c</b>) SPA + VIP-LightGBM.</p>
Full article ">
33 pages, 9468 KiB  
Article
Assessing Data Fusion in Sensory Devices for Enhanced Prostate Cancer Detection Accuracy
by Jeniffer Katerine Carrillo Gómez, Carlos Alberto Cuastumal Vásquez, Cristhian Manuel Durán Acevedo and Jesús Brezmes Llecha
Chemosensors 2024, 12(11), 228; https://doi.org/10.3390/chemosensors12110228 - 1 Nov 2024
Viewed by 548
Abstract
The combination of an electronic nose and an electronic tongue represents a significant advance in the pursuit of effective detection methods for prostate cancer, a widespread form of cancer affecting men across the globe. These cutting-edge devices, collectively called “E-Senses”, use data fusion [...] Read more.
The combination of an electronic nose and an electronic tongue represents a significant advance in the pursuit of effective detection methods for prostate cancer, a widespread form of cancer affecting men across the globe. These cutting-edge devices, collectively called “E-Senses”, use data fusion to identify distinct chemical compounds in exhaled breath and urine samples, potentially improving existing diagnostic techniques. This study combined the information from two sensory perception devices to detect prostate cancer in biological samples (breath and urine). To achieve this, data from patients diagnosed with the disease and from control individuals were collected using a gas sensor array and chemical electrodes. The signals were subjected to data preprocessing algorithms to prepare them for analysis. Following this, the datasets for each device were individually analyzed and subsequently merged to enhance the classification results. The data fusion was assessed and it successfully improved the accuracy of detecting prostate-related conditions and distinguishing healthy patients, achieving the highest success rate possible (100%) in classification through machine learning methods, outperforming the results obtained from individual electronic devices. Full article
Show Figures

Figure 1

Figure 1
<p>Scheme of E-Senses for improving PCa detection.</p>
Full article ">Figure 2
<p>eNose System: (<b>a</b>) Sampling device for breath collection using a disposable mouthpiece, (<b>b</b>) Sampling protocol for urine collection generating a headspace.</p>
Full article ">Figure 3
<p>Radar plot of sensor responses of eNose for prostate conditions (PCa, BPH, prostatitis, and healthy patients). (<b>a</b>) Breath samples signals, and (<b>b</b>) urine samples HS signals.</p>
Full article ">Figure 4
<p>(<b>a</b>) PCA plot of PCa and control categories of urine samples using eNose, (<b>b</b>) PCA plot of urine samples (PCa vs. BPH, prostatitis, and healthy) using eNose.</p>
Full article ">Figure 5
<p>DFA plot for PCa and control categories classification of urine samples using eNose.</p>
Full article ">Figure 6
<p>(<b>a</b>) PCA plot of PCa vs. control categories of breath samples using eNose, (<b>b</b>) PCA analysis of PCa vs. control categories of breath samples using eNose.</p>
Full article ">Figure 7
<p>DFA plot of PCa vs. control categories of breath samples by using eNose.</p>
Full article ">Figure 8
<p>Signals acquired with eTongue based on C110 electrode for distinguishing between PCa (orange) and controls (green) in urine samples.</p>
Full article ">Figure 9
<p>PCA plot of C110 electrode using eTongue. (<b>a</b>) PCa and control categories of urine samples and, (<b>b</b>) PCa vs. BPH, prostatitis, and healthy urine samples.</p>
Full article ">Figure 10
<p>DFA plot of PCa and control categories for urine samples by using eTongue.</p>
Full article ">Figure 11
<p>Signals from measurements acquired with eTongue with 250BT electrode for detecting PCa and controls using urine samples.</p>
Full article ">Figure 12
<p>(<b>a</b>) PCA plot of PCa and control groups urine samples using 250BT electrode with eTongue. (<b>b</b>) PCA plot of PCa vs. BPH, prostatitis, and healthy urine samples using 250BT electrode with eTongue.</p>
Full article ">Figure 13
<p>DFA plot of PCa and control groups urine samples acquired with −250BT electrode with eTongue.</p>
Full article ">Figure 14
<p>(<b>a</b>) PCA plot of PCa and control groups urine samples acquired using C110 and 250BT electrodes with eTongue. (<b>b</b>) PCA plot of PCa vs. BPH, prostatitis, and healthy urine samples using eTongue (C110 and 250BT electrodes).</p>
Full article ">Figure 15
<p>DFA plot of PCa vs. BPH, prostatitis, and healthy urine samples acquired with eTongue (C110 and 250BT).</p>
Full article ">Figure 16
<p>PCA plot of PCa and control groups with breath and urine measurements acquired with eNose system.</p>
Full article ">Figure 17
<p>PCA loadings plot for PCa and control groups with breath and urine measurements acquired with eNose system.</p>
Full article ">Figure 18
<p>PCA plot of prostate cancer and related disease categories through breath and urine measurements acquired with eNose system.</p>
Full article ">Figure 19
<p>DFA plot of prostate cancer and related disease categories through breath and urine measurements acquired with eNose system.</p>
Full article ">Figure 20
<p>PCA plot of prostate cancer and control categories through urine samples acquired with eNose and eTongue (C110 electrode) systems.</p>
Full article ">Figure 21
<p>Confusion matrix obtained from PCA-SVM classification model for urine samples (PCa vs. control) using eNose and eTongue (C110 electrode).</p>
Full article ">Figure 22
<p>DFA classification of prostate cancer and control categories through breath and urine samples acquired with eNose and eTongue (C110 electrode) systems.</p>
Full article ">Figure 23
<p>Confusion matrix obtained from DFA-SVM classification model of urine samples (PCa vs. control) using eNose and eTongue (C110 electrode).</p>
Full article ">Figure 24
<p>PCa plot of prostate cancer and related conditions categories through urine measurements acquired with eNose and eTongue (C110 electrode) systems.</p>
Full article ">Figure 25
<p>Confusion matrix obtained from PCA-SVM classification model of urine samples (PCa vs. related diseases) using eNose and eTongue (C110 electrode).</p>
Full article ">Figure 26
<p>DFA plot of PCa and related disease categories through urine measurements acquired with eNose and eTongue (C110 electrode) systems.</p>
Full article ">Figure 27
<p>Confusion matrix obtained from DFA-KNN classification model of urine samples (PCa vs. related diseases) using eNose and eTongue (C110 electrode).</p>
Full article ">Figure 28
<p>(<b>a</b>) PCA plot of prostate cancer and control categories through breath and urine measurements acquired with eNose and eTongue (C110/250BT electrodes) systems. (<b>b</b>) PCA plot of prostate cancer and related diseases through breath and urine measurements acquired with eNose and eTongue (C110 electrode) systems.</p>
Full article ">Figure 29
<p>DFA classification of prostate cancer and related conditions through breath and urine measurements acquired with eNose and eTongue (C110/250BT electrodes) systems.</p>
Full article ">Figure 30
<p>Confusion matrix of prostate cancer and related diseases through breath and urine measurements acquired with eNose and eTongue (C110/250BT electrodes) systems applying DFA and SVM models.</p>
Full article ">
14 pages, 4241 KiB  
Article
Comparison of Aroma and Taste Profiles Between Two Fermented Pea Pastes Using Intelligent Sensory Analysis and Gas Chromatography–Mass Spectrometry
by Tianyang Wang, Lian Yang, Wanting Tang, Haibin Yuan, Chuantao Zeng, Ping Dong, Yuwen Yi, Jing Deng, Huachang Wu and Ju Guan
Fermentation 2024, 10(11), 543; https://doi.org/10.3390/fermentation10110543 - 24 Oct 2024
Viewed by 474
Abstract
The traditionally produced pea paste (PP) suffers from suboptimal flavor and inferior quality. Based on the study of single-strain fermentation, we further selected S. cerevisiae, Z. rouxii, and L. paracasei for PP production by dual-strain fermentation (SL, ZL). By combining intelligent [...] Read more.
The traditionally produced pea paste (PP) suffers from suboptimal flavor and inferior quality. Based on the study of single-strain fermentation, we further selected S. cerevisiae, Z. rouxii, and L. paracasei for PP production by dual-strain fermentation (SL, ZL). By combining intelligent sensory technology, gas chromatography–mass spectrometry (GC-MS), and ultra-high-performance liquid chromatography (UPLC) technology, the aroma and taste characteristics of SL- and ZL-fermented PP were compared. The electronic nose and tongue revealed the differences in the aroma and taste characteristics between the two fermentation methods for fermenting PP. In total, 74 volatile compounds (VOCs) in PP were identified through GC-MS analysis. In contrast, the number of VOCs and the concentrations of alcohols and acids compounds in SL were higher than in ZL. Among the 15 VOCs that were common to both and had significant differences, the concentrations of ethanol, 1-pentanol, and ethyl acetate were higher in SL. For taste characteristics, SL demonstrated significantly higher levels of sweet and bitter amino acids, as well as tartaric acid, compared with ZL. These results elucidate the flavor differences of dual-strain fermented PP, providing a theoretical basis for selecting suitable strains for fermenting PP. Full article
(This article belongs to the Special Issue Analysis of Quality and Sensory Characteristics of Fermented Products)
Show Figures

Figure 1

Figure 1
<p>The rPCA model based on the response values of the intelligent sensory E-nose and E-tongue sensors. (<b>a</b>,<b>c</b>) Score chart of the model’s load, (<b>b</b>,<b>d</b>) Pearson correlation coefficients of the sensors’ response value and its importance to PC 1.</p>
Full article ">Figure 2
<p>The types and relative contents of volatile organic compounds in SL and ZL, represented as (<b>a</b>) a pie chart and (<b>b</b>) a bar chart. A, B, C, D, E, F, and G in the figure represent alcohols, aldehydes, acids, esters, ketones, heterocycles, and others, respectively. The number after the letter indicates the quantity of the compound. *** indicates a significant difference according to Tukey’s HSD and a post facto test (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 3
<p>The rPCA model established on basis of the concentration of compounds with significant differences found by GC-MS. (<b>a</b>) Score map of model loading; (<b>b</b>) Pearson correlation coefficients between the concentration of each compound and its importance on PC 1.</p>
Full article ">Figure 4
<p>The rPCA model was established on the basis of the concentration of compounds with significant differences found via the free amino acid content. (<b>a</b>) Score map of model loading; (<b>b</b>) Pearson correlation coefficients between the concentration of each compound and its importance on PC 1, (<b>c</b>) Histogram of the taste properties of free amino acids. *** indicates a significant difference by Tukey’s HSD and a post facto test (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 5
<p>The rPCA established from the content of six organic acids detected in PP. (<b>a</b>) Score map of model loading; (<b>b</b>) Pearson correlation coefficients between the concentration of each compound and its importance on PC 1. (<b>c</b>) Bar chart of the classification of six organic acids.* and *** denote statistically significant and highly significant differences, respectively.</p>
Full article ">Figure 6
<p>Spearman’s correlation heatmap, showing correlations between compounds and the sensors’ responses. (<b>a</b>) Correlation between volatile compound levels and the electronic nose sensors’ responses. (<b>b</b>) Correlation between organic acids/free amino acids and the electronic tongue sensors’ reactions. Red represents positive correlations, and blue represents negative correlations. The symbols “*” and “**” represent significance at <span class="html-italic">p</span> &lt; 0.05 and <span class="html-italic">p</span> &lt; 0.01, respectively.</p>
Full article ">
14 pages, 4946 KiB  
Article
Pediatric Orally Disintegrating Tablets (ODTs) with Enhanced Palatability Based on Propranolol HCl Coground with Hydroxypropyl-β-Cyclodextrin
by Marzia Cirri, Paola A. Mura, Francesca Maestrelli, Simona Benedetti and Susanna Buratti
Pharmaceutics 2024, 16(11), 1351; https://doi.org/10.3390/pharmaceutics16111351 - 23 Oct 2024
Viewed by 610
Abstract
Background: Propranolol, largely prescribed as an antihypertensive and antiarrhythmic drug in pediatrics, is characterized by a bitter taste and an astringent aftertaste. Currently, the therapy requires crushing of tablets for adults and their dispersion in water many times a day, leading to loss [...] Read more.
Background: Propranolol, largely prescribed as an antihypertensive and antiarrhythmic drug in pediatrics, is characterized by a bitter taste and an astringent aftertaste. Currently, the therapy requires crushing of tablets for adults and their dispersion in water many times a day, leading to loss of dosing accuracy, low palatability, and poor compliance for both patients and caregivers. Objectives: This work aimed to exploit cyclodextrin complexation by cogrinding to develop orally disintegrating tablets (ODTs) endowed with reliable dosing accuracy, good palatability and safety, ease of swallowability, and ultimately better compliance for both pediatric patients and caregivers. Results: Different formulation variables and process parameters were evaluated in preparing ODTs. The technological and morphological characterization and disintegration tests were performed according to official and alternative tests to select the ODT formulation based on the drug Hydroxypropyl-β-cyclodextrin (HPβCD) coground complex form containing Pearlitol® Flash as the diluent and 8% Explotab® as the superdisintegrant, which demonstrated the highest % drug dissolution in simulated saliva and acceptable in vitro palatability assessed by the electronic tongue, confirming the good taste-masking power of HPβCD towards propranolol. Conclusions: Such a new dosage form of propranolol could represent a valid alternative to the common extemporaneous preparations, overcoming the lack of solid formulations of propranolol intended for pediatric use. Full article
Show Figures

Figure 1

Figure 1
<p>Simulated wetting test of drug-loaded ODT. (<b>1</b>): ODT (4A/7A) before testing; (<b>2</b>): swelling of ODT 4A (8% SD) at the end of the test (21 s); (<b>3</b>): swelling of ODT 7A (16% SD) at the end of the test (28 s).</p>
Full article ">Figure 2
<p>SEM micrographs of selected ODT formulations (9-A, (<b>left</b>) and 9-B, (<b>right</b>)) of tablet surfaces at different magnifications (<b>up</b>) and their cross-section (<b>down</b>).</p>
Full article ">Figure 3
<p>% Drug dissolution in simulated saliva at 37 °C of ODTs containing pure propranolol (ODT drug) or drug:HPβCD as P.M. with 8% SD (ODT P.M. 8% SD) and 16% SD (ODT P.M. 16% SD), or drug:HPβCD as GR with 8% SD (ODT GR 6′ B′) and 16% SD (ODT GR 9′ B′).</p>
Full article ">Figure 4
<p>PCA score plot (<b>a</b>) and loading plot (<b>b</b>) of the collected e-tongue data.</p>
Full article ">Figure 5
<p>Bar graph of the bitterness scores of pure drug, ODT formulations, and ODT placebos.</p>
Full article ">
19 pages, 2457 KiB  
Article
Influences of Lactiplantibacillus plantarum dy-1 Fermentation on the Bitterness of Bitter Melon Juice, the Composition of Saponin Compounds, and Their Bioactivities
by Juan Bai, Zihan Yang, Wei Luo, Ying Zhu, Yansheng Zhao, Beibei Pan, Jiayan Zhang, Lin Zhu, Shiting Huang and Xiang Xiao
Foods 2024, 13(20), 3341; https://doi.org/10.3390/foods13203341 - 21 Oct 2024
Viewed by 705
Abstract
Lactic acid bacteria fermentation is a beneficial bioprocessing method that can improve the flavor, transform nutrients, and maintain the biological activity of foods. The aim of this study is to investigate the effects of Lactiplantibacillus plantarum dy-1 fermentation on the nutritional components, flavor [...] Read more.
Lactic acid bacteria fermentation is a beneficial bioprocessing method that can improve the flavor, transform nutrients, and maintain the biological activity of foods. The aim of this study is to investigate the effects of Lactiplantibacillus plantarum dy-1 fermentation on the nutritional components, flavor and taste properties, and composition of saponin compounds and their hypolipidemic and antioxidant activities. The results suggested that the total polyphenol content increased, and the soluble polysaccharides and total saponin contents decreased in fermented bitter melon juice (FJ) compared with those in non-fermented bitter melon juice (NFJ). The determination of volatile flavor substances by GC-MS revealed that the response values of acetic acid, n-octanol, sedumol, etc., augmented significantly, and taste analysis with an electronic tongue demonstrated lower bitterness and higher acidity in FJ. Furthermore, UPLC-Q-TOF-MS/MS testing showed a significant decrease in bitter compounds, including momordicines I and II, and a significant increase in the active saponin momordicine U in the fermented bitter melon saponin group (FJBMS). The in vitro assays indicated that FJBMS exhibited similar antioxidant activities as the non-fermented bitter melon saponin group (NFBMS). The in vitro results show that both NFBMS and FJBMS, when used at 50 μg/mL, could significantly reduce fat accumulation and the malondialdehyde (MDA) content and increased the catalase (CAT) activity, while there was no significant difference in the bioactivities of NFBMS and FJBMS. In conclusion, Lactiplantibacillus plantarum dy-1 fermentation is an effective means to lower the bitterness value of bitter melon and preserve the well-known bioactivities of its raw materials, which can improve the edibility of bitter melon. Full article
(This article belongs to the Special Issue Fermented Foods: Microbiology, Technology, and Health Benefits)
Show Figures

Figure 1

Figure 1
<p>Effect of fermentation on the substance composition of bitter melon juice in each group. (<b>A</b>) Determination of the pH of bitter melon juice with a pH meter. (<b>B</b>) Determination of soluble polysaccharides in bitter melon juice by the phenol sulfuric acid method. (<b>C</b>) Determination of total phenols of bitter melon juice, using the Folin–Ciocalteu method. (<b>D</b>–<b>G</b>) Substance number plots, PCA plots, Venn diagrams, and heatmap, obtained from the determination of volatile compounds in bitter melon juice by GC-MS. A, B, and C represent Fresh, NFJ, and FJ, respectively. Different letters indicated the variability of the three groups of samples (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 2
<p>Effects of fermentation on the taste of bitter melon juice. (<b>A</b>) and (<b>B</b>) Principal component analysis of three kinds of bitter melon juice, based on the results from electronic tongue determination. As shown in Figure (<b>B</b>), A, B, and C, respectively, represent Fresh, NFJ, and FJ. (<b>C</b>) The sensor data of bitter melon juice was determined by the electronic tongue, and is divided into AHS (acidity), PKS (general purpose), CPS (general purpose), SCS (bitterness), and ANS (sweetness). Different letters indicate the variability of the three groups of samples (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 3
<p>Effect of fermentation on the saponin composition of bitter melon juice in each group. UPLC-Q-TOF-MS/MS was used to determine the saponin composition of each group. (<b>A</b>) Determination of the total saponin of BMS. (<b>B</b>,<b>C</b>) PLS-DA score plots of three kinds of bitter melon juices in positive and negative ion modes. (<b>D</b>,<b>E</b>) Positive and negative ion OPLS-DA score plots of unfermented and fermented bitter melon samples. (<b>F</b>,<b>G</b>) Positive and negative ion S-plot graphs of unfermented and fermented bitter melon samples. (<b>H</b>) Significant changes in composition before and after dy-1 fermentation. Different letters indicate the variability of the three groups of samples (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 4
<p>Effect of fermentation on the antioxidant activity of BMS in vitro. (<b>A</b>) ABTS and (<b>B</b>) DPPH clearance of BMS and VC at different concentrations. Different letters indicate the variability of the four groups of samples at each concentration (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 5
<p>Effect of fermentation on the lipid-lowering and antioxidant activity of BMS. (<b>A</b>) L1-stage <span class="html-italic">C. elegans</span> nematodes were treated with different concentrations of NFBMS and FJBMS for 48 h. The lipids in the nematodes were stained using oil red O stain. The number following the name represents the administered concentrations. The unit was μg/mL. For example, ‘NFBMS 25’ indicates that NFBMS was administered at a concentration of 25 μg/mL. (<b>B</b>–<b>D</b>) The TG content, CAT activity, and MDA content of L1 stage <span class="html-italic">C. elegans</span> after 48 h of treatment were determined using assay kits. Different letters indicate the variability of the four groups (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">
16 pages, 3126 KiB  
Article
Assessment of Changes in Sensory Characteristics of Strawberries during 5-Day Storage through Correlation between Human Senses and Electronic Senses
by Md Shakir Moazzem, Michelle Hayden, Dong-Joo Kim and Sungeun Cho
Foods 2024, 13(20), 3269; https://doi.org/10.3390/foods13203269 - 15 Oct 2024
Viewed by 694
Abstract
In the last decade, significant efforts have been made to predict sensory characteristics using electronic senses, such as the electronic nose (e-nose) and the electronic tongue (e-tongue), and discuss their relationship to the eating quality evaluated by human panels. This study was conducted [...] Read more.
In the last decade, significant efforts have been made to predict sensory characteristics using electronic senses, such as the electronic nose (e-nose) and the electronic tongue (e-tongue), and discuss their relationship to the eating quality evaluated by human panels. This study was conducted (1) to characterize the aroma and taste profiles of strawberries over a 5-day storage period (4 °C) using both electronic senses and human panels and (2) to correlate the electronic sense data with human panel data. A total of 10 sensory attributes of strawberries, including 7 aroma and 3 taste attributes, were analyzed by a descriptive sensory panel (n = 16) over the five days. Although the human panel did not find significant differences in the intensities of the strawberry attributes over the five days, the intensity ratings showed an increasing or decreasing trend over the storage period. However, the e-nose and the e-tongue discriminated each of the storage days of the strawberry samples. Furthermore, the partial least square regression coefficients of determination (R2) indicated that the e-nose and the e-tongue were highly predictive in their evaluation of the intensities of all the descriptive sensory attributes. Lastly, the concentrations of furaneol, one of the key volatiles imparting a distinct ripe strawberry aroma, were determined using an e-nose to correlate with the intensities of aroma attributes evaluated by the panel. A significant positive Pearson’s correlation coefficient was found with the intensities of overripe aroma. The findings indicate the potential of electronic senses to determine sensory characteristics and their excellent capability to predict the eating quality of strawberries. Full article
Show Figures

Figure 1

Figure 1
<p>Intensities of aroma attributes (<b>a</b>) and taste attributes (<b>b</b>) of strawberry samples (S1, S2, and S3) throughout the 5-day storage period analyzed by a descriptive trained panel (n = 16). Intensities were rated on a 15 cm line scale. No significant differences were found within the sample over the 5-day period (<span class="html-italic">p</span> &gt; 0.05).</p>
Full article ">Figure 2
<p>Electronic nose principal component analysis biplots indicating aroma profile changes in strawberry samples over the 5-day period. Three commercial strawberry samples are (<b>a</b>) S1, (<b>b</b>) S2, and (<b>c</b>) S3.</p>
Full article ">Figure 3
<p>Volatile compounds in different chemical group comparisons among three strawberry samples (S1, S2, and S3).</p>
Full article ">Figure 4
<p>Electronic tongue principal component analysis biplots indicating taste profile changes in strawberry samples over the 5-day period. Three commercial strawberry samples are (<b>a</b>) S1, (<b>b</b>) S2, and (<b>c</b>) S3.</p>
Full article ">Figure 5
<p>Furaneol standard curve using electronic nose (Alpha MOS, Heracles, Toulouse, France). Furaneol contents can be calculated using the equation (y = 150.41x + 406.15) in the graph (x = Furaneol concentration (mg/mL); y = Peak area calculated from e-nose analysis).</p>
Full article ">Figure 6
<p>Pearson’s correlation heatmap indicating relationships between furaneol content (mg/mL) and descriptive aroma attributes (fruity, floral, sweet, green, pungent, overripe, and overall aroma) in strawberry samples.</p>
Full article ">
16 pages, 2049 KiB  
Article
Potentiometric Electronic Tongue for the Evaluation of Multiple-Unit Pellet Sprinkle Formulations of Rosuvastatin Calcium
by Patrycja Ciosek-Skibińska, Krzysztof Cal, Daniel Zakowiecki and Joanna Lenik
Materials 2024, 17(20), 5016; https://doi.org/10.3390/ma17205016 - 14 Oct 2024
Viewed by 652
Abstract
Sprinkle formulations represent an interesting genre of medicinal products. A frequent problem, however, is the need to mask the unpleasant taste of these drug substances. In the present work, we propose the use of a novel sensor array based on solid-state ion-selective electrodes [...] Read more.
Sprinkle formulations represent an interesting genre of medicinal products. A frequent problem, however, is the need to mask the unpleasant taste of these drug substances. In the present work, we propose the use of a novel sensor array based on solid-state ion-selective electrodes to evaluate the taste-masking efficiency of rosuvastatin (ROS) sprinkle formulations. Eight Multiple Unit Pellet Systems (MUPSs) were analyzed at two different doses (API_50) and (API_10), as well as pure Active Pharmaceutical Ingredient (API) as a bitter standard. Calcium phosphate-based starter pellets were coated with the mixture containing rosuvastatin. Some of them were additionally coated with hydroxypropyl methylcellulose, which was intended to separate the bitter substance and prevent it from coming into contact with the taste buds. The sensor array consisted of 16 prepared sensors with a polymer membrane that had a different selectivity towards rosuvastatin calcium. The main analytical parameters (sensitivity, selectivity, response time, pH dependence of potential, drift of potential, lifetime) of the constructed ion-selective electrodes sensitive for rosuvastatin were determined. The signals from the sensors array recorded during the experiments were processed using Principal Component Analysis (PCA). The results obtained, i.e., the chemical images of the pharmaceutical samples, indicated that the electronic tongue composed of the developed solid-state electrodes provided respective attributes as sensor signals, enabling both of various kinds of ROS pellets to be distinguished and their similarity to ROS bitterness standards to be tested. Full article
Show Figures

Figure 1

Figure 1
<p>Rosuvastatin((3R,5S,6E)-7-[4-(4-fluorophenyl)-2-(N-ethylmethanesulfonamido)-6-(propan-2-yl)pyrimidin-5-yl]-3,5-dihydroxyhept-6-ene acid).</p>
Full article ">Figure 2
<p>Schematic presentation of ISE and potentiometric sensor array.</p>
Full article ">Figure 3
<p>Dynamic response for electrodes no. 5, 6, 10 (<b>a</b>) and for electrodes no. 11 and 12 (<b>b</b>).</p>
Full article ">Figure 4
<p>Potential drift of the selected electrodes in 2 × 10<sup>−4</sup> mol L<sup>−1</sup> rosuvastatin solution during one hour.</p>
Full article ">Figure 5
<p>Effect of the pH on the potential response of the selected electrodes in 2 × 10<sup>−4</sup> mol L<sup>−1</sup> of rosuvastatin solution.</p>
Full article ">Figure 6
<p>Stability of sensitivity of the electrode no. 11 in time.</p>
Full article ">Figure 7
<p>PCA score plot of electronic tongue results for the studied formulations (A–H). and pure API (API_10 and API_50).</p>
Full article ">Figure 8
<p>PC1 values of the electronic tongue results showing gradually changing characteristics of the studied formulations (A–H), compared to pure API standards (API_10 and API_50).</p>
Full article ">Figure 9
<p>HCA showing the discrimination of ROS samples. Dashed lines represent a division into 2 groups at variance weighted distance &gt; 30, and 3 groups at variance weighted distance ~20.</p>
Full article ">
24 pages, 8540 KiB  
Review
A Review of Advanced Sensor Technologies for Aquatic Products Freshness Assessment in Cold Chain Logistics
by Baichuan Wang, Kang Liu, Guangfen Wei, Aixiang He, Weifu Kong and Xiaoshuan Zhang
Biosensors 2024, 14(10), 468; https://doi.org/10.3390/bios14100468 - 30 Sep 2024
Viewed by 1069
Abstract
The evaluation of the upkeep and freshness of aquatic products within the cold chain is crucial due to their perishable nature, which can significantly impact both quality and safety. Conventional methods for assessing freshness in the cold chain have inherent limitations regarding specificity [...] Read more.
The evaluation of the upkeep and freshness of aquatic products within the cold chain is crucial due to their perishable nature, which can significantly impact both quality and safety. Conventional methods for assessing freshness in the cold chain have inherent limitations regarding specificity and accuracy, often requiring substantial time and effort. Recently, advanced sensor technologies have been developed for freshness assessment, enabling real-time and non-invasive monitoring via the detection of volatile organic compounds, biochemical markers, and physical properties. The integration of sensor technologies into cold chain logistics enhances the ability to maintain the quality and safety of aquatic products. This review examines the advancements made in multifunctional sensor devices for the freshness assessment of aquatic products in cold chain logistics, as well as the application of pattern recognition algorithms for identification and classification. It begins by outlining the categories of freshness criteria, followed by an exploration of the development of four key sensor devices: electronic noses, electronic tongues, biosensors, and flexible sensors. Furthermore, the review discusses the implementation of advanced pattern recognition algorithms in sensor devices for freshness detection and evaluation. It highlights the current status and future potential of sensor technologies for aquatic products within the cold chain, while also addressing the significant challenges that remain to be overcome. Full article
(This article belongs to the Special Issue Biosensing Strategies for Food Safety Applications)
Show Figures

Figure 1

Figure 1
<p>Aquatic product freshness assessment.</p>
Full article ">Figure 2
<p>Principle and overview of electronic nose system. (<b>A</b>) Schematic representation of the RHINOS e-nose workflow for odor prediction including odor sample collection, sensor signal processing, and AI-based odor concentration prediction. Reproduced with permission [<a href="#B73-biosensors-14-00468" class="html-bibr">73</a>]. Copyright 2021, Elsevier. (<b>B</b>) Schematic representation of the sensor array with 20 monolayer OFETs. Reproduced with permission [<a href="#B59-biosensors-14-00468" class="html-bibr">59</a>]. Copyright 2023, American Chemical Society. (<b>C</b>) The RHINOS e-nose device and its interface with a computer for real-time data analysis. Reproduced with permission [<a href="#B73-biosensors-14-00468" class="html-bibr">73</a>]. Copyright 2021, Elsevier. (<b>D</b>) The top view of a portable electronic nose based on digital and analog chemical sensors. Reproduced with permission [<a href="#B60-biosensors-14-00468" class="html-bibr">60</a>]. Copyright 2022, MDPI. (<b>E</b>) RHINOS sensing chamber hosting 21 chemical sensors and a combination sensor for temperature, humidity, and pressure. Reproduced with permission [<a href="#B73-biosensors-14-00468" class="html-bibr">73</a>]. Copyright 2021, Elsevier. (<b>F</b>) Schematic diagram of the electronic nose system. Reproduced with permission [<a href="#B74-biosensors-14-00468" class="html-bibr">74</a>]. Copyright 2024, Elsevier.</p>
Full article ">Figure 3
<p>Principle and overview of electronic tongue system. (<b>A</b>) Schematic representation of the E-tongue workflow for odor and taste determination. Reproduced with permission [<a href="#B87-biosensors-14-00468" class="html-bibr">87</a>]. Copyright 2023, Elsevier. (<b>B</b>) Schematic representation of the chemical tongue with a representative element (fluorogenic polymer). Reproduced with permission [<a href="#B88-biosensors-14-00468" class="html-bibr">88</a>]. Copyright 2022, Springer Nature. (<b>C</b>) Photo of the potentiometric E-tongue used for the on-line measurement at an aeration plant and detail of the sensors. Reproduced with permission [<a href="#B89-biosensors-14-00468" class="html-bibr">89</a>]. Copyright 2022, Elsevier. (<b>D</b>) The front view and cross-sectional view of electronic tongue sensor strip. Reproduced with permission [<a href="#B90-biosensors-14-00468" class="html-bibr">90</a>]. Copyright 2008, MDPI. (<b>E</b>) TS-5000Z taste sensing system, Intelligent Sensor Technology Inc., Kanagawa, Japan. Reproduced with permission [<a href="#B91-biosensors-14-00468" class="html-bibr">91</a>]. Copyright 2018, MDPI. (<b>F</b>) Lab-made E-tongue device: sensor arrays, data logger, and control software installed on a PC [<a href="#B92-biosensors-14-00468" class="html-bibr">92</a>]. Copyright 2021, MDPI. (<b>G</b>) Paper-based electronic tongue system applied for discrimination. Reproduced with permission [<a href="#B91-biosensors-14-00468" class="html-bibr">91</a>]. Copyright 2018, MDPI. (<b>H</b>) Sensor matrix in the form of a swallowable capsule. Reproduced with permission [<a href="#B91-biosensors-14-00468" class="html-bibr">91</a>]. Copyright 2018, MDPI. (<b>I</b>) Example of an electronic tongue system with individual sensing modules applied for the analysis of fermentation: 1. Inlet, 2. Outler, 3. Reference electrode, 4. Single modules with individual sensors, 5. Electronic connections. Reproduced with permission [<a href="#B91-biosensors-14-00468" class="html-bibr">91</a>]. Copyright 2018, MDPI.</p>
Full article ">Figure 4
<p>Overview of biosensors application. (<b>A</b>) Schematic diagram of the needle-type enzyme sensor system and images of the detector region. Reproduced with permission [<a href="#B111-biosensors-14-00468" class="html-bibr">111</a>]. Copyright 2019, Springer Nature. (<b>B</b>) Schematic representation of the operation of light-dependent bio-electrochemical systems [<a href="#B112-biosensors-14-00468" class="html-bibr">112</a>]. Copyright 2019, Elsevier. (<b>C</b>) Schematic diagram of the wireless biosensor system for fish. 1 Needle-type enzyme sensor, 2 waterproof sheet, 3 wireless potentiated, 4 nylon threads, 5 receiver, 6 personal computer, 7 test fish (Nile tilapia <span class="html-italic">Oreochromis niloticus</span>) [<a href="#B111-biosensors-14-00468" class="html-bibr">111</a>]. Copyright 2019, Springer Nature. (<b>D</b>) Schematic diagram of biosensor for detecting the blood glucose of live fish [<a href="#B113-biosensors-14-00468" class="html-bibr">113</a>]. Copyright 2022, Elsevier. (<b>E</b>) AEFishBIT biosensor attached to Atlantic salmon (<span class="html-italic">Salmo salar</span>) operculum using surgical thread and self-piercing fish tag [<a href="#B114-biosensors-14-00468" class="html-bibr">114</a>]. Copyright 2021, MDPI.</p>
Full article ">Figure 5
<p>Overview of biosensors application. (<b>A</b>) Diagram of design layout and schematic of the hydrogel coating flexible pH sensor system for TVB-N monitoring. Reproduced with permission [<a href="#B132-biosensors-14-00468" class="html-bibr">132</a>]. Copyright 2022, Elsevier. (<b>B</b>) Schematic representation of the electronic-free and low-cost wireless sensor tag for monitoring fish freshness [<a href="#B133-biosensors-14-00468" class="html-bibr">133</a>]. Copyright 2023, Elsevier. (<b>C</b>) Schematic diagram of A screen printed flexible RFID tag for O<sub>2</sub> monitoring [<a href="#B134-biosensors-14-00468" class="html-bibr">134</a>]. Copyright 2023, Elsevier. (<b>D</b>) Schematic diagram of flexible wireless pH sensor system based on ITO coated flexible PET substrate for fish quality detection [<a href="#B133-biosensors-14-00468" class="html-bibr">133</a>]. Copyright 2023, Elsevier.</p>
Full article ">
17 pages, 3575 KiB  
Article
An Electronic “Tongue” Based on Multimode Multidirectional Acoustic Plate Wave Propagation
by Nikita Ageykin, Vladimir Anisimkin, Andrey Smirnov, Alexander Fionov, Peng Li, Zhenghua Qian, Tingfeng Ma, Kamlendra Awasthi and Iren Kuznetsova
Sensors 2024, 24(19), 6301; https://doi.org/10.3390/s24196301 - 29 Sep 2024
Viewed by 604
Abstract
This paper theoretically and experimentally demonstrates the possibility of detecting the five basic tastes (salt, sweet, sour, umami, and bitter) using a variety of higher-order acoustic waves propagating in piezoelectric plates. Aqueous solutions of sodium chloride (NaCl), glucose (C6 [...] Read more.
This paper theoretically and experimentally demonstrates the possibility of detecting the five basic tastes (salt, sweet, sour, umami, and bitter) using a variety of higher-order acoustic waves propagating in piezoelectric plates. Aqueous solutions of sodium chloride (NaCl), glucose (C6H12O6), citric acid (C6H8O7), monosodium glutamate (C5H8NO4Na), and sagebrush were used as chemicals for the simulation of each taste. These liquids differed from each other in terms of their physical properties such as density, viscosity, electrical conductivity, and permittivity. As a total acoustic response to the simultaneous action of all liquid parameters on all acoustic modes in a given frequency range, a change in the propagation losses (ΔS12) of the specified wave compared with distilled water was used. Based on experimental measurements, the corresponding orientation histograms of the ΔS12 were plotted for different types of acoustic waves. It was found that these histograms for different substances are individual and differ in shape, area, and position of their extremes. Theoretically, it has been shown that the influence of different liquids on different acoustic modes is due to both the electrical and mechanical properties of the liquids themselves and the mechanical polarization of the corresponding modes. Despite the fact that the mechanical properties of the used liquids are close to each other, the attenuation of different modes in their presence is not only due to the difference in their electrical parameters. The proposed approach to creating a multi-parametric multimode acoustic electronic tongue and obtaining a set of histograms for typical liquids will allow for the development of devices for the operational analysis of food, medicines, gasoline, aircraft fuel, and other liquid substances without the need for detailed chemical analysis. Full article
(This article belongs to the Special Issue Feature Papers in Physical Sensors 2024)
Show Figures

Figure 1

Figure 1
<p>The basic design used in the study of liquid media using acoustic waves in piezoelectric plates.</p>
Full article ">Figure 2
<p>A photo of an experimental setup with four acoustic channels on a single piezoelectric 128°<span class="html-italic">Y LiNbO<sub>3</sub></span> wafer. (1) 128°<span class="html-italic">Y LiNbO<sub>3</sub></span> wafer, (2) interdigital transducers (IDTs), (3) cell for liquid. The angles between the acoustic channels and the crystallographic <span class="html-italic">X</span>-axis are <span class="html-italic">Θ</span> = 0°, 30°, and 90° и 120°.</p>
Full article ">Figure 3
<p>A typical view of the frequency dependence of the insertion losses <span class="html-italic">S</span><sub>12</sub> of acoustic waves in 128°<span class="html-italic">Y-X LiNbO<sub>3</sub></span> with distilled water (black line) and a 0.9% aqueous <span class="html-italic">NaCl</span> (<span class="html-italic">σ</span> = 1.4 S/m) solution (red line) in a cell. The arrows indicate some waves with high total losses.</p>
Full article ">Figure 4
<p>Geometry of the problem.</p>
Full article ">Figure 5
<p>Experimental orientational dependencies of Δ<span class="html-italic">S</span><sub>12</sub> for acoustic waves with different operating frequencies: ~34 MHz (black line), ~37 MHz (red line), ~41 MHz (green line), ~44 MHz (blue line), and ~48 MHz (light blue line) propagating in a 128°<span class="html-italic">Y LiNbO<sub>3</sub></span> plate with a normalized thickness of <span class="html-italic">h</span>/<span class="html-italic">λ</span> = 2.5 in the presence of 0.9% aqueous solutions of (<b>a</b>) <span class="html-italic">NaCl</span>, (<b>b</b>) glucose, (<b>c</b>) citric acid, (<b>d</b>) monosodium glutamate, and (<b>e</b>) sagebrush.</p>
Full article ">Figure 6
<p>Combined taste histograms of monosodium glutamate (<b>a</b>) and sagebrush (<b>b</b>) aqueous solutions with concentrations of 0.02% (red line) and 0.9% (black line) measured using the entire set of acoustic modes in a given frequency range and all channels of the 128°<span class="html-italic">Y LiNbO<sub>3</sub></span> plate with a normalized thickness <span class="html-italic">h</span>/<span class="html-italic">λ</span> = 2.5.</p>
Full article ">
18 pages, 12397 KiB  
Article
Metabolite Profiling and Identification of Sweet/Bitter Taste Compounds in the Growth of Cyclocarya Paliurus Leaves Using Multiplatform Metabolomics
by Liang Chen, Dai Lu, Yuxi Wan, Yaqian Zou, Ruiyi Zhang, Tao Zhou, Bin Long, Kangming Zhu, Wei Wang and Xing Tian
Foods 2024, 13(19), 3089; https://doi.org/10.3390/foods13193089 - 27 Sep 2024
Viewed by 761
Abstract
Cyclocarya paliurus tea, also known as “sweet tea”, an herbal tea with Cyclocarya paliurus leaves as raw material, is famous for its unique nutritional benefits and flavor. However, due to the unique “bittersweet” of Cyclocarya paliurus tea, it is still unable to fully [...] Read more.
Cyclocarya paliurus tea, also known as “sweet tea”, an herbal tea with Cyclocarya paliurus leaves as raw material, is famous for its unique nutritional benefits and flavor. However, due to the unique “bittersweet” of Cyclocarya paliurus tea, it is still unable to fully satisfy consumers’ high-quality taste experience and satisfaction. Therefore, this study aimed to explore metabolites in Cyclocarya paliurus leaves during their growth period, particularly composition and variation of sweet and bitter taste compounds, by combining multi-platform metabolomics analysis with an electronic tongue system and molecular docking simulation technology. The results indicated that there were significant differences in the contents of total phenols, flavonoids, polysaccharides, and saponins in C. paliurus leaves in different growing months. A total of 575 secondary metabolites were identified as potential active metabolites related to sweet/bitter taste using nontargeted metabolomics based on UHPLC-MS/MS analysis. Moreover, molecular docking technology was utilized to study interactions between the candidate metabolites and the sweet receptors T1R2/T1R3 and the bitter receptors T2R4/T2R14. Six key compounds with high sweetness and low bitterness were successfully identified by using computational simulation analysis, including cis-anethole, gluconic acid, beta-D-Sedoheptulose, asparagine, proline, and citrulline, which may serve as candidates for taste modification in Cyclocarya paliurus leaves. These findings provide a new perspective for understanding the sweet and bitter taste characteristics that contribute to the distinctive sensory quality of Cyclocarya paliurus leaves. Full article
Show Figures

Figure 1

Figure 1
<p>Bar chart of sweetness and bitterness values of <span class="html-italic">C. paliurus</span> leaves in different growth months. Notes: Q5–Q9 refer to the samples of the leaves of <span class="html-italic">C. paliurus</span> collected from May to September. <sup>a–e</sup> Means within the same taste value with different superscripts differ significantly (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 2
<p>TPC, TFC, TP, and TSC from <span class="html-italic">C. paliurus</span> leaves. Notes: TPC (total phenolic content), TFC (total flavonoid content), TP (total polysaccharide content), and TSC (total saponin content). Q5–Q9 refer to the samples of the leaves of <span class="html-italic">C. paliurus</span> collected from May to September. <sup>a–e</sup> Means within the same indicator with different superscripts differ significantly (<span class="html-italic">p</span> &lt; 0.05).</p>
Full article ">Figure 3
<p>Associations between six key metabolites and the rest of the indices. Notes: The color gradient from red to blue on the chart illustrates the intensity of correlation coefficients, with red indicating the weakest association and blue representing the strongest.</p>
Full article ">Figure 4
<p>Nontargeted metabolomics analysis. (<b>A</b>) The circus plot of differential metabolites. Notes: Circus circle plot is arranged from the outside inwards in the following order: metabolite names, HMDB classifications of metabolites, p-values, VIP from PLS-DA analysis, and correlation lines. Arcs connecting any two points on the circle are called chords, indicating a correlation between the two points. (<b>B</b>) The proportion of various metabolites in <span class="html-italic">C. paliurus</span> leaf samples. Notes: Various color-coded sections denote items categorized under distinct chemical groups, with the corresponding percentages indicating the proportion of items within each chemical category. The proportion of metabolites is calculated as a fraction of the total metabolites detected. Those metabolites lacking a defined chemical classification are categorized as “others”.</p>
Full article ">Figure 5
<p>Multivariate analyses of <span class="html-italic">C. paliurus</span> leaf samples. (<b>A</b>) Principal component analysis (PCA) of metabolite profiles across different groups. (<b>B</b>) OPLS-DA permutation test plot of the comparison groups. (<b>C</b>) The bar chart of significant KEGG enrichment pathways. (<b>D</b>) The diagram of pathway impact. (<b>E</b>) The flavone and flavanol biosynthesis pathways.</p>
Full article ">Figure 6
<p>Homologous modeling and screening process of molecular docking. (<b>A</b>) Sweet receptors (T1R1/TIR3) and bitter receptors (T2R4/T2R14). (<b>B</b>) Interaction patterns of hT2R14 with cis-anethole, gluconic acid and citrulline; (<b>a</b>) hT2R14–cis-anethole, (<b>b</b>) hT2R14–gluconic acid, (<b>c</b>) hT2R14–citrulline. (<b>C</b>) Six core sweet- and bitter-related metabolites.</p>
Full article ">
13 pages, 3469 KiB  
Article
An Integration of UPLC-Q-TOF-MS, GC-MS, Electronic Nose, Electronic Tongue, and Molecular Docking for the Study of the Chemical Properties and Flavor Profiles of Moringa oleifera Leaves
by Mingxiao Zhang, Mengjia Guo, Na Chen, Zhuqian Tang, Junjie Xiang, Lixin Yang, Guohua Wang, Bin Yang and Hua Li
Chemosensors 2024, 12(9), 199; https://doi.org/10.3390/chemosensors12090199 - 23 Sep 2024
Viewed by 903
Abstract
Moringa oleifera leaves (MOLs) have gained significant attention due to their nutritional and biological activity. Therefore, this study aimed to examine its flavor characteristics and underlying compositions. In this study, we used ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), gas [...] Read more.
Moringa oleifera leaves (MOLs) have gained significant attention due to their nutritional and biological activity. Therefore, this study aimed to examine its flavor characteristics and underlying compositions. In this study, we used ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), gas chromatography-mass spectrometry (GC-MS), electronic nose, electronic tongue, and molecular docking to comprehensively investigate the chemical properties and flavor profiles of MOLs. UPLC-Q-TOF-MS and GC-MS were instrumental in identifying the 20 non-volatile and 19 volatile constituents of MOLs, respectively. The electronic nose and electronic tongue systems provided an objective evaluation of the sweet, bitter, and spicy attributes and flavor characteristics of MOLs. Concurrently, molecular docking was employed to elucidate the material basis of flavor profiles. It revealed that glucosinolates and flavonoids are probably the key components for the bitter taste of MOLs. The sweet taste may be attributed to glucosinolates and flavonoids. The spicy scent appears to be linked to the presence of glucosinolates and alkaloids. The integration of these techniques confers a thorough understanding of the chemical composition and sensory properties of MOLs. These findings have significant implications for innovative applications in the food industry as well as pharmaceuticals and agriculture sectors; furthermore, they contribute towards enhancing the perception of Moringa oleifera as a valuable natural resource. Full article
(This article belongs to the Section Analytical Methods, Instrumentation and Miniaturization)
Show Figures

Figure 1

Figure 1
<p>PLS−DA plot of electronic tongue measurement data. Note: 9 Radix Scutellariae, 10 Radix Isatidis, 11 Radix et Rhizoma Rhei, 12 Radix Sophorae Tonkinensis, 13 Cortex Magnoliae Officinalis, 14 Folium Isatidis, 15 Aloe, 16 Radix Sophorae Flavescentis, 17 Rhizoma Coptidis, 18 Cortex Phellodendri, 19 Radix Glycyrrhizae, 20 Radix Codonopsis, 21 Radix Aloe, 22 Rhizoma Polygoni Multiflori, 23 Folium Sennae, 24 Fructus Cannabis, 25 Radix Bupleuri, 26 Radix Astragali, 27 Flos Lonicerae, 28 Semen Sinapis, 29 Rhizoma Chuanxiong, 30 Radix Angelicae Dahuricae, 31 Semen Raphani, 32 Semen Lepidii, 38 Moringa leaves (PKM1), 39 Moringa leaves (PKM2), 40 Moringa leaves (YD), 41 Moringa leaves (HH).</p>
Full article ">Figure 2
<p>ROC curve (<b>left</b>) and confusion matrix (<b>right</b>) of the artificial neural network by E-tongue.</p>
Full article ">Figure 3
<p>PLS−DA plot of the electronic nose measurement data. Note: 1 Mustard, 2 Angelica, 3 Chuanxiong, 4 Asarum, 5 Perilla leaves, 6 Tinglizi, 7 Magnolia, 8 Polygala, 9 Platycodon grandiflorum, 10 Tangerine peel, 11 Raphani, 12 Angelica, 13 Cinnamon, 14 Saposhnikovia divaricata, 15 Pueraria, 16 Moringa leaves (PKM1), 17 Moringa leaves (PKM2), 18 Moringa leaves (YD), 19 Moringa leaves (HH).</p>
Full article ">Figure 4
<p>ROC curve (<b>left</b>) and confusion matrix (<b>right</b>) of the artificial neural network by E-nose.</p>
Full article ">Figure 5
<p>Molecular docking. Bitter taste proteins: (<b>A</b>) T2R10, (<b>B</b>) T2R14, (<b>C</b>) T2R38. Sweet taste proteins: (<b>D</b>) T1R2, (<b>E</b>) T1R3. Spicy taste proteins: (<b>F</b>) TRPV1, (<b>G</b>) OR7D4.</p>
Full article ">
9 pages, 2559 KiB  
Communication
Impact of Coffee Roasting and Grind Size on Acidity and Bitterness: Sensory Evaluation Using Electronic Tongue
by Masaaki Habara and Toshihide Horiguchi
Chemosensors 2024, 12(9), 196; https://doi.org/10.3390/chemosensors12090196 - 23 Sep 2024
Viewed by 957
Abstract
Coffee flavor is profoundly influenced by numerous factors, including the origin’s terroir and variety, as well as post-harvest processing, drying, and sorting. Even specialty coffee beans, carefully selected for their high quality, can exhibit a wide range of flavor profiles depending on how [...] Read more.
Coffee flavor is profoundly influenced by numerous factors, including the origin’s terroir and variety, as well as post-harvest processing, drying, and sorting. Even specialty coffee beans, carefully selected for their high quality, can exhibit a wide range of flavor profiles depending on how they are roasted and ground. Traditionally, the coffee industry has used the Brewing Control Chart, which considers total dissolved solids (TDS) and extraction (E), to guide professionals toward achieving consistent flavors. However, this chart has limitations in representing the complex chemical composition and its influence on the sensory attributes of coffee. This study explores a more comprehensive approach to evaluating coffee quality by utilizing a taste sensing system (electronic tongue) to measure acidity and bitterness for full-immersion brewing. We investigate the impact of brew ratio and grind size on these taste attributes, while also considering the influence of roast level. Our findings demonstrate that finer grind sizes significantly affect TDS and E, while roast level and grind size significantly affect sensory attributes, as measured by the taste sensing system. This approach complements the traditional Brewing Control Chart by providing a more nuanced understanding of how roast level and grind size influence coffee flavor. Full article
(This article belongs to the Special Issue Electronic Nose and Electronic Tongue for Substance Analysis)
Show Figures

Figure 1

Figure 1
<p>The Brewing Control Chart in the (<b>left</b>) figure visually represents the relationship between total dissolved solids (TDS) and extraction (E) in brewed coffee, with diagonal lines indicating different brew ratios. This chart is commonly used by the coffee industry to guide professionals in achieving consistent and desirable flavors. In the equilibrium state of full-immersion brews, E becomes nearly constant regardless of the brew ratio and converges to the gray region, as shown in the (<b>right</b>) figure. It was created based on Liang’s report [<a href="#B7-chemosensors-12-00196" class="html-bibr">7</a>].</p>
Full article ">Figure 2
<p>The relationship between total dissolved solids (TDS) and extraction (E) for 16 coffee samples prepared with different grind sizes and roast levels. Each data point represents a unique combination of roast level (L* value) and grind size setting (corresponding to median particle size). The inset graph shows the distribution of L* values and grind sizes used in this study.</p>
Full article ">Figure 3
<p>The positioning of the 16 extracted coffee samples on the Brewing Control Chart, highlighting the lack of distinction between different roast levels despite variations in grind size.</p>
Full article ">Figure 4
<p>A contour map depicting the relationship between the estimated intensity of acidity (EIT<span class="html-italic"><sub>acidity</sub></span>), roast level (L* value), and grind size at full-immersion brewing. The non-parallel contour lines indicate a non-linear relationship between these variables and acidity, with grind size exerting a stronger influence at lighter roast levels.</p>
Full article ">Figure 5
<p>A contour map illustrating the relationship between the estimated intensity of bitterness (EIT<span class="html-italic"><sub>bitterness</sub></span>), roast level (L* value), and grind size at full-immersion brewing. The non-parallel contour lines suggest a more pronounced impact of grind size on bitterness at darker roast levels.</p>
Full article ">
15 pages, 5144 KiB  
Article
Insights into the Flavor Profile of Yak Jerky from Different Muscles Based on Electronic Nose, Electronic Tongue, Gas Chromatography–Mass Spectrometry and Gas Chromatography–Ion Mobility Spectrometry
by Bingde Zhou, Xin Zhao, Luca Laghi, Xiaole Jiang, Junni Tang, Xin Du, Chenglin Zhu and Gianfranco Picone
Foods 2024, 13(18), 2911; https://doi.org/10.3390/foods13182911 - 14 Sep 2024
Viewed by 798
Abstract
It is well known that different muscles of yak exhibit distinctive characteristics, such as muscle fibers and metabolomic profiles. We hypothesized that different muscles could alter the flavor profile of yak jerky. Therefore, the objective of this study was to investigate the differences [...] Read more.
It is well known that different muscles of yak exhibit distinctive characteristics, such as muscle fibers and metabolomic profiles. We hypothesized that different muscles could alter the flavor profile of yak jerky. Therefore, the objective of this study was to investigate the differences in flavor profiles of yak jerky produced by longissimus thoracis (LT), triceps brachii (TB) and biceps femoris (BF) through electronic nose (E-nose), electronic tongue (E-tongue), gas chromatography–mass spectrometry (GC-MS) and gas chromatography–ion mobility spectrometry (GC-IMS). The results indicated that different muscles played an important role on the flavor profile of yak jerky. And E-nose and E-tongue could effectively discriminate between yak jerky produced by LT, TB and BF from aroma and taste points of view, respectively. In particular, the LT group exhibited significantly higher response values for ANS (sweetness) and NMS (umami) compared to the BF and TB groups. A total of 65 and 47 volatile compounds were characterized in yak jerky by GC-MS and GC-IMS, respectively. A principal component analysis (PCA) model and robust principal component analysis (rPCA) model could effectively discriminate between the aroma profiles of the LT, TB and BF groups. Ten molecules could be considered potential markers for yak jerky produced by different muscles, filtered based on the criteria of relative odor activity values (ROAV) > 1, p < 0.05, and VIP > 1, namely 1-octen-3-ol, eucalyptol, isovaleraldehyde, 3-carene, D-limonene, γ-terpinene, hexanal-D, hexanal-M, 3-hydroxy-2-butanone-M and ethyl formate. Sensory evaluation demonstrated that the yak jerky produced by LT exhibited superior quality in comparison to that produced by BF and TB, mainly pertaining to lower levels of tenderness and higher color, taste and aroma levels. This study could help to understand the specific contribution of different muscles to the aroma profile of yak jerky and provide a scientific basis for improving the quality of yak jerky. Full article
(This article belongs to the Special Issue Quantitative NMR and MRI Methods Applied for Foodstuffs)
Show Figures

Figure 1

Figure 1
<p>Sample preparation flowchart. <span class="html-italic">Longissimus thoracis</span> (LT), <span class="html-italic">triceps brachii</span> (TB) and <span class="html-italic">biceps femoris</span> (BF).</p>
Full article ">Figure 2
<p>Score plot and loading plot of robust principal component analysis (rPCA) models based on electronic nose (E-nose) (<b>a</b>,<b>b</b>) and electronic tongue (E-tongue) (<b>c</b>,<b>d</b>) response data.</p>
Full article ">Figure 3
<p>(<b>a</b>) Venn diagram plot of the number of volatile compounds in yak jerky from different muscles. (<b>b</b>) Bar plot of the percentage of volatile compound species in yak jerky from different muscles. (<b>c</b>) Principal component analysis (PCA) model based on volatile compounds in yak jerky from different muscles. (<b>d</b>) VIP score plots for the partial least-squares discriminant analysis (PLS-DA) model on volatile compounds in yak jerky from different muscles.</p>
Full article ">Figure 4
<p>Gas chromatography–ion mobility spectrometry (GC-IMS) observation results of yak jerky from different muscles. (<b>a</b>) 3D topographic plot. (<b>b</b>) Subtraction plot, with spectra from TB group as a reference and the corresponding spectra from LT and BF groups represented as differences from TB group. (<b>c</b>) Gallery plots indicating the variations in volatile compounds’ concentrations among the four groups. Red and blue colors highlight over- and underexpressed components, respectively.</p>
Full article ">Figure 5
<p>(<b>a</b>) Bar plot of the relative content of volatile compound species in yak jerky from different muscles characterized by GC-IMS. (<b>b</b>) Venn diagram plot of the number of volatile compounds characterized by GC-MS and GC-IMS.</p>
Full article ">Figure 6
<p>The rPCA model was established based on the relative content of GC-IMS differential volatile compounds. (<b>a</b>) The score plot shows the samples from the three groups as follows: squares (LT), circles (TB) and triangles (BF). The median of each group is represented by a wide and empty circle. (<b>b</b>) The loading plot illustrates the significant correlation between the molecule concentration and their importance along PC 1.</p>
Full article ">Figure 7
<p>Radar chart for sensory evaluation of yak jerky from different muscles.</p>
Full article ">Figure 8
<p>Correlation analysis of E-nose, E-tongue, sensory evaluation and volatile compounds quantified by GC-IMS (<b>a</b>) and GC-MS (<b>b</b>). The size of node is indicative of the number of substances that are significantly correlated with the substance in question. The blue circles represent the E-nose and E-tongue probes; the pink squares represent volatile compounds; and the yellow triangles represent sensory evaluation. In addition, the larger the node, the greater the number of substances with which it is significantly correlated. The thickness of line is representative of the size of the absolute value of the correlation between two substances. In this context, the thicker the line, the greater the absolute value of the correlation between the two substances.</p>
Full article ">
Back to TopTop