Postharvest

Green and blue mold, caused by Penicillium digitatum (Pers.) Sacc. and P. italicum Wehmer, respectively, cause significant losses of Satsuma mandarins (Citrus unshiu Marc.) after harvest. The effects of some pre-and postharvest treatments on development of these ...

In developing countries, food losses occur mainly during the production, harvest, postharvest and processing phases. Because of the lack of awareness in the apple postharvest practices in Lebanon, this study was carried out to check the effect of good harvesting and handling practices, pre-storage sorting, and dipping in calcium and fungicide, on the percent losses of Golden Delicious apples during six months of cold storage. A highly significant reduction in the percent of total damages was observed during storage when good harvesting and handling practices and pre-storage sorting were applied. The magnitude of losses reduction depended on the type of damage registered and the practices performed. The presence of injuries was reduced by all types of good practices, applied alone or in combination. Where good harvesting and handling practices were performed, the incidence of bruising was reduced from 93.3% in the non-treated control to 37.7% and symptoms of rot were not detected. This study emphasized the importance of good harvest and postharvest practices in improving and maintaining the quality of Lebanese apples.

This experiment was conducted to study the effectiveness of different preservative solutions on vase life and quality of angelica cut inflorescences cv. Single. The concentrations of citric acid at 100, 200 and 300 mg L-1, sucrose at 3% and 4% and H2O2 at 0.1%, 0.2% and 0.3% were used as preservatives, while distilled water was used as control. The single factor experiment was laid out in a completely randomized design (CRD) with three replications. Citric acid and H2O2 solutions effectively inhibited bacterial growth-related blockage in the vascular tissues, but had adverse effects on the vase life. The inflorescences stored in sucrose (3% and 4%) solutions remained fresh up to 10 days after preservation (DAP), maintaining good solution uptake, controlling transpiration loss and gaining higher relative fresh weight. Different quality parameters like floret diameter and number of opened florets were also significantly higher in inflorescences preserved in sucrose (3% and 4%) solutio...

This study assessed the effects of antioxidant edible coating on the walnut green husk extract (WGHE) in combination with ascorbic acid (AsA) and the effects were studied on the postharvest quality of fresh kernels (FKs). FKs were dipped in distilled water (Control), WGHE (0.15 and 0.3 g L −1), AsA 1 % and the combination of treatments. The samples were stored for 60 days at 4 ± 1 °C with 93 % relative humidity. The results showed that low temperature increased the levels of total phenols (TP), reduced the polyphenol oxidase (PPO) enzyme activities after 15 days of storage and preserved the antioxidant activity (AC) for up to 30 days of storage. Compared with uncoated kernels, all coated samples inhibited the increase in microbial growth, peroxide index (PI) and PPO activity. The values of TP, AC, color and sensory properties were also significantly preserved as a result of coating the FKs. In summary, all edible coatings may be used to extend the shelf life of the FKs in dry environment.

BACKGROUND: Tomato fruit is of prime importance owing to its qualities for human nutrition and its economic value. In order to extend its commercial life, it is harvested at mature but unripe stages and stored at low temperatures. The goal of this work was to study the ...

Avoiding mechanical damage and controlling time-temperature relationships are key factors for satisfactorily handling and storing olives during the period from harvesting to milling. A ten-point list of handling and storage practices is proposed as well as a semi-log diagram for the choice of suitable time-temperature relationship. The criteria for optimizing the harvesting-milling link are discussed.

This paper study the performance evaluation of a refrigeration system that operates on solar energy as alternative source of power to enhance the refrigerating effect, coefficient of performance (COP), preservation of perishable items and short time drug such as vaccine, to remote communities and parts of the urban settlement around the developing nations where there is no access to modern electrical source. The system was made from locally sourced materials using a conventional refrigerant HFC134a as working fluid to improve thermal efficiency and stability of the vapour compression refrigeration system. The COP of the system was enhanced by 8.67% when working with solar and with energy reduction of 2.38% respectively. In case the weather is cloudy or during the night hour when the energy generation is low, the refrigerator can work on battery for an average of 12 hours if fully charge during the day to avoid idle time of the refrigeration system.

Treatments for reducing latex injury in mango fruit (Mangifera indica). The objective of this study was to evaluate the effect of alternative treatments to reduce mango sapburns in fresh mangoes. Amarilla cultivar mangoes and water solutions of ether lauril sodium sulfonate (ELSS 1%), sulfonic acid (AS 1%), coconut amide (AC 1%), ethoxylated nonil phenol (NFE, 1%), sodium hypochlorite (100 and

The motor-operated cassava grater was developed, fabricated and evaluated using locally available and low-cost materials for household-level processing. Peeled cassava tubers were grated at three various grating drum rotational speed determined by using three pulley diameters (5, 6 and 8 in) with an average speed of 1424.30 rpm, 1148.30 rpm, and 857.40 rpm, respectively. The cassava grater was run by 1.5-hp electric motor and its performance was evaluated in terms of grating capacity, grating efficiency, percentage loss and fineness modulus (FM). Each parameter was statistically analyzed using completely randomized design. The manual grating was also conducted in comparison to the fabricated machine. From the parameters tested, the 5-in diameter pulley with an average grating capacity of 283.26 kg/hr, grating efficiency of 91.56%, percentage loss of only 8.44% and FM of 3.38 is highly recommended.

Agriculture is the backbone of Tanzanian economy. It accounts for about one-third of the gross domestic product (GDP), provides 85 percent of all exports and saves as a livelihood to over 80 percent of the total population. Maize is the primary staple crop; it’s grown in nearly all agro-ecological zones in the country. Tanzania is a major maize producer in Sub-Saharan
Africa. In the last four decades, Tanzania has ranked among the top 25 maize producing countries in the world. In the 2013/14 growing seasons. Tanzania produced over half billion metric tons of maize of these maize smallholder farmers produced around 85%. Despite the steady production of maize over the past three decades, post-harvest losses of maize remained significant, up to 30-40 % in some rural areas. Post-harvest handling, poor infrastructure, weather variability, biotic factors such as insects and pests, bacteria, pathogens, viruses, and fungi, often aggravate such losses. Mycotoxin producing fungi pose a major risk. Mycotoxins are toxic secondary metabolites of fungi that frequently contaminate the maize in the field and/or during storage. Mycotoxin contamination of maize poses a health risk to humans and animals if not properly managed. The most important mycotoxins in Tanzania are the aflatoxins, fumonisins and Ochratoxin. The objective of this paper was to review current literature on the production trends, consumption, post-harvest losses, and mycotoxins contamination of maize and to provide strategies to control and prevent postharvest losses and mycotoxins contamination in Tanzania

'Carabao' mango was harvested green at different stages of maturity [100, 105, 110, 115, 120 and 125 d after flower induction (DAFI)] and subjected to nondestructive firmness test using a universal testing machine. A 7.9-mm diameter plunger with rounded tip (6.9-mm radius of curvature) was pressed onto whole fruit at 10 mm min-1 crosshead speed, to produce deformations of 0.8, 1.3, and 1.8 mm; additional fruits were tested until rupture for comparison. Total soluble solids (TSS), titratable acidity (TA) and pH were measured at the green stage and at the table-ripe stage (TRS) after ripening at 25 °C. Sensory analysis was performed at TRS to determine the best harvest maturity. Results showed no significant differences in TSS, TA and pH between maturities at the green stage; hence, physico-chemical properties could not be used to test for maturity. Sensory analysis at TRS showed that fruit harvested at 115–120 DAFI gave the best eating quality in terms of aroma, sweetness, sourness, flavor and overall acceptability. Fruits harvested at 125 DAFI showed significantly lower sensory scores. Significant differences in rupture force (F R , kN) and fruit stiffness (B, kN mm-1 of deformation) were observed between maturities at the green stage; however, the nondestructive deformation test at 0.8 mm was more sensitive to fruit maturity. Fruits harvested at 115–120 DAFI had significantly lower values for B and load ratio at 0.8-mm to 0.5-mm deformation (F 0.8 /F 0.5) compared with earlier harvest dates. Analysis of the normal distribution curve of a prediction set of 40 mature (MAT) fruits showed that 80% of the samples had B ≤ 1.360 kN mm-1 and F 0.8 /F 0.5 ≤ 1.883. Based on the use of signal detection theory and these values as thresholds, 66.3% (by B) and 58.8% (by F 0.8 /F 0.5) of immature or overmature (I/O) fruit could be detected. Analysis of a separate validation set of fruit using the same threshold values gave respective detection rates of I/O fruit of 68.8% using B and 60.0% using F 0.8 /F 0.5 .

The loss of market values and problem of pests in the stored grains has contributed to the problem of food security in Africa. Post-harvest losses due to Sitophilus zeamais remain an important constraint to grain storage in Africa. Also, use of chemical insecticides have increased food poisoning thus there is resurgence need of using botanical pesticides to control insect pests in the field as well as in storage. This study investigated the insecticidal effects of some botanicals (Eucalyptus camaldulensis Dehnh., Mangifera indica L., Carica papaya L. and Nicotiana tabacum L. leaves) on Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidea) F1 progeny and mortality as well as weight loss of Maize. The botanicals at varying concentrations (0.1 g, 0.5 g and 1.0 g) were applied on 500 g of maize for 3 months. All the leaf powders used exhibited insecticidal properties against Sitophilus zeamais in stored maize grains. However, they are more effective at the 1.0 g/500 g of maize grain, with Nicotiana tabacum being the most effective. At 1.0 g/500 g of maize grain, the botanicals had effect on the proximate composition of the maize grains with Mangifera indica causing a reduction in the carbohydrate content of the maize grains. The results of the experiment revealed that leaf powders of Nicotiana tabacum, Mangifera indica, Carica papaya and Eucalyptus camaldulensis have great potential to be used as pesticides against Sitophilus zeamais in stored maize grain. Therefore, these botanical powders can be used as an alternative to synthetic chemical for the control of S.
zeamais.

In this paper, experimental analysis was carried out on a vapour compression system by varying the parallel tube condenser fins spacing under the same atmospheric condition in a selected Refrigeration and Air-conditioning laboratory to examine the performance characteristics of the refrigeration system. The fins spacing were 2, 4 and 6 mm using Liquefied petroleum gas (LPG) as working fluid with a mixture proportion of 17.2% isobutene, 56.4% butane, 24.4% propane. The result shows that the coefficient of performance of the system when working with condenser fins spacing of 2 mm was 28.8 and 35.9% higher compared to when the system worked with the fins spacing of 4 and        6 mm respectively. Energy consumed by the single hermetic compressor when the system worked with condenser fins spacing of 2 mm reduced by 16.4 and 18.7% compared to when the refrigerator worked with fins spacing of 4 and 6 mm respectively. The pull down time of the cooling system was attained in 2 hours 45 minute with minimum evaporator temperature of -13 ℃ while working with 30 g mass charge of LPG.

Ripening, storability, quality attributes, and postharvest losses in fruits are interlinked with one another. The postharvest life of a fruit is primarily determined by various physiological processes and associated metabolic changes occurring in the fruit. The role of the external atmosphere in reg¬ulating the above processes and changes is relatively better understood. However, little is known about the overall internal atmosphere of the fruit and how it influences different aspects of ripening and storability. This chapter looks into this emerging area: the basic and applied importance of the internal atmosphere to postharvest physiology and food science and technology. There are various gases and volatiles that make the internal atmosphere of fruits. Their production and diffusion across the fruit tissues are governed by many factors. Differences in morphological, anatomical, and microstructural features of fruits are now assuming greater impor¬tance, as they are involved in determining the internal environment of fruits. As a consequence, there exists variability in the internal atmosphere of fruits, which is evident not only at the level of different species, but also within species. Differences in ripening behavior of different fruits under plant-attached and -detached conditions are also expected in view of the above. The involvement of some of gases (ethylene, oxygen, and carbon dioxide) and volatiles (ethanol, acetaldehyde, water vapors and water sta¬tus, salicylic acid and methyl salicylate, jasmonic acid and jasmonates, and nitric oxide) in the regulation of ripening-related changes, including flavor and aroma, is described and discussed at the individual as well as at the interactive level (especially with ethylene). Some examples are presented wherein endogenous and exogenous volatiles exhibit a positive effect on the fruit’s storability, quality, and tolerance to biotic and abiotic stresses. Lastly, a few researchable issues are suggested. The outcome from this area can supplement the existing storage technologies, and this will be highly desirable in achieving a more effective and holistic way of the postharvest management of perishable commodities.