Three, summary of the invention:
Technical problem technical problem to be solved by this invention is at the deficiency of existing Juice kind in the market, proposes a kind of original local flavor of pumpkin, pineapple, apple and watermelon, sugar-acid ratio is moderate, mouthfeel is good composite natural fruit and vegetable juice of keeping.
A kind of pumpkin composite juice of technical scheme is characterized in that, wherein in volume ratio, Pumpkin Juice content is 40%~60%, pineapple juice 21%~35%, cider 12%~17% and watermelon juice 7%~13%, xanthans 0.02%, pectin 0.06%.
The preparation method of above-mentioned pumpkin composite juice is:
A) choosing ripe fresh pumpkin cleans, removes the peel, goes flesh, fragmentation and making beating to make crushed pumpkin, between 40 ℃~60 ℃, be incubated 1~2h, filter with 60~80 order vibratory sieves, filtrate is carried out the instantaneous enzyme that goes out of high temperature under 90 ℃~99 ℃, enzyme time of going out is 5~10s, cool to room temperature obtains Pumpkin Juice rapidly;
B) choosing ripe pineapple, apple and watermelon is raw material, cleans, removes the peel, goes flesh, fragmentation and making beating to make aquatic foods and squeeze the juice, wherein 100% cider that is reduced into of the also available concentrated apple juice of cider;
C) Pumpkin Juice, pineapple aquatic foods are squeezed the juice, cider and watermelon aquatic foods squeeze the juice and mix in the described ratio of claim 1, add 0.02% xanthans and 0.06% pectin, homogeneous is 2 times under 20~40Mpa, obtains the pumpkin composite juice of stable homogeneous;
D) with the pumpkin composite juice at 65 ℃~75 ℃, vacuum is vacuum outgas under 0.06~0.08Mpa, then at 121 ℃ of high-temperature short-time sterilization 5~10s, promptly obtains finished product pumpkin composite juice.
The finished product pumpkin composite juice soluble solid that is obtained is 6.5~7.0 Brix degrees (° Brix), and total acid content is 0.50%~0.64%.
Beneficial effect compared with prior art, Pumpkin Juice of the present invention and preparation technology thereof have the following advantages:
(1) the present invention proposes to be incubated the method for process for producing Pumpkin Juice first.The pumpkin composite juice that is provided, the local flavor and the multiple nutritional components of pineapple, apple and watermelon can have been merged well, soluble solid is 6.5~7.0 Brix degrees (° Brix), total organic acids content is 0.50%~0.64%, pulp precipitated and separated phenomenon can not appear in flavor coordination, does not have cooked flavor, do not contain anticorrisive agent, be the pure natural pumpkin composite juice;
(2) precipitate operation without enzymolysis and pectin tannin among the preparation method of Pumpkin Juice of the present invention, not only reduced the nutrition health influence of chemical assistant to Juice, various nutritional labelings have been kept simultaneously effectively, not only mouthfeel is good to make the pumpkin composite juice of producing, and be of value to the healthy of drinking person, be a kind of Juice of pure natural;
(3) among the pumpkin composite juice preparation method of the present invention Juice the heating high temperature number of times of process few, and temperature is suitable, thereby when guaranteeing bactericidal effect, reduce the harmful effect of high temperature to greatest extent, make the pumpkin composite juice of producing keep the natural flavor of pumpkin Juice local flavor and color and luster;
(4) preparation method of pumpkin composite juice of the present invention is simple, technology advanced person, and small investment, cost is low.
Four, the specific embodiment
1, temperature retention time and temperature determines
Table 1 temperature retention time is to the influence of indexs such as Pumpkin Juice suspension stability
As shown in Table 1, insulation is handled in 0~2.5h scope, and the suspension stability of Pumpkin Juice is the back downward trend that rises earlier, reaches the highest (0.375) during 1.5h.After 1.5h was handled in insulation, suspension stability slightly descended, and changed not obvious behind the 2h.The Pumpkin Juice suspension stability was best when as seen, temperature retention time was 1.5h.Pectin is variation tendency and suspension stability basically identical in time, illustrates that pectin content and suspension stability are proportionate under certain condition, and this is because pectin can form the colloidal suspension system with the particulate matter in the Normal juice, has reduced the generation of precipitation.When temperature retention time surpassed 2h, the crushing juice rate of pumpkin, reduced sugar, soluble solid content changed not obvious, but content beta-carotene obviously descends.
Table 2 Temperature Treatment is to the influence of indexs such as Pumpkin Juice suspension stability
By table 2 as seen, when temperature was 45 ℃, the Pumpkin Juice suspension stability was high by 13% during than 40 ℃; In 45 ℃~60 ℃ scopes, temperature raises, and suspension stability continues to descend.This is because too high temperature makes the enzyme system that acts in the pumpkin lose vigor.Crushing juice rate and soluble solid temperature influence variation tendency are not obvious, and content of reducing sugar raises with temperature and slightly rises, and content beta-carotene descended when temperature was higher.The index of quality such as the stability of comprehensive Pumpkin Juice, crushing juice rate, content beta-carotene, holding temperature is a surname with 45 ℃.
2, best flavor determination of formula
Table 3 pumpkin composite juice allotment testing program and result
The local flavor of pumpkin composite juice is important organoleptic quality index, and the consumer is to determine its purchase and the principal element of drinking to the preference of local flavor.The present invention uses the definite optimum formula based on Pumpkin Juice, compound pineapple juice, cider and watermelon juice of the optimum Mixed Design of D-, and the measured value of its subjective appreciation and predicated response value see Table 3, and subjective appreciation adopts 7 fens method for makings.Utilize the data in the Design Expert software his-and-hers watches 1 to analyze, obtain the regression equation of subjective appreciation predicted value Pumpkin Juice (A), pineapple juice (B), cider (C) and watermelon juice (D):
y=6.06×A+5.38×B+5.76×C+4.23×D+0.32×A×B+0.29×A×C+1.49×A×D+1.30×B×C+4.53×B×D+3.50×C×D
The prediction of table 4 subjective appreciation maximum
Model variance analysis (table 4) is shown, the subjective appreciation forecast model reaches the level of signifiance, the model coefficient correlation reaches 0.8356, behind the compound fruit and vegetable juice allotment test result analysis, obtain by Pumpkin Juice, pineapple juice, cider and watermelon juice the peaked predicted value of Juice subjective appreciation after compound, see Table 4.Pumpkin Juice content is 40% in the compound fruit and vegetable juice, pineapple juice 30%, and when cider 17% and watermelon juice 13%, the subjective appreciation predicted maximum is 6.18.Give prominence to the novel aroma of Pumpkin Juice, the tasty and refreshing flavour of pineapple juice with this compound Juice of filling a prescription, merged cider and watermelon juice local flavor preferably simultaneously, easy for consumers to accept.
3, selection of stabilizers
Several stabilizing agents of table 5 are to the stabilization of pumpkin composite juice
In the pumpkin composite juice, add different stabilizers and combination thereof, after homogeneous, sterilization, store 7d down, observe its stablizing effect (table 5) then at 35 ℃.The result shows that in xanthans, CMC, pectin and four kinds of stabilizing agents commonly used of guar gum, when these two kinds of stabilizing agents of xanthans and pectin acted on the pumpkin composite juice separately, beverage flow was good, and stablizing effect is good; The stablizing effect of CMC and guar gum is relatively poor, does not declare the stabilizing agent as the pumpkin composite juice.
4, stabilizing agent is compound
According to the single factor experiment result, carry out the orthogonal test of two factors, three levels with xanthans (0.02%, 0.04%, 0.06%) and pectin (0.04%, 0.06%, 0.08%).The suspension stability (table 6) of mensuration this pumpkin composite juice after homogeneous and sterilization.
Table 6 compound stabilizer is to the influence of suspension stability
The stability that increases the pumpkin composite juice is to improve the key of its end product quality.According to Stokes formula as can be known, can improve the viscosity of Juice, help the raising of stability by adding stabilizing agent.Experimental result (table 6) shows that when adding xanthans and pectin in this pumpkin composite juice, along with the increase of xanthans concentration, the suspension stability of pumpkin composite juice descends; When adding 0.02% xanthans, the suspension stability of pumpkin composite juice is best, and this moment, the addition of pectin was little to the suspension stability influence.As shown in Table 6, when adding 0.02% xanthans and 0.06% pectin, lamination does not appear in this pumpkin composite juice, and suspension stability is also better, the consumption when both additions all are lower than single interpolation the, and the good stability of pumpkin composite juice.
5, homogenization pressure, number of times and temperature are to the influence of stability
Make the pulp particle homogenising of different grain size, different specific weight by homogeneous, to increase the suspension stability of fruit squash, desire to make homogeneous to reach ideal effect, homogenization pressure and temperature will be controlled proper, if homogeneous is excessive, the viscosity of pumpkin composite juice descends, and precipitation significantly increases, and stability reduces on the contrary.And the effect of homogeneous mainly is subjected to the influence of homogenization pressure, number of times and feed temperature, and when feed temperature is 40 ℃, during homogeneous 1 time, its suspension stability sees Table 7 under different homogenization pressures.
Table 7 homogenization pressure is to the influence of homogenizing effect
As shown in Table 7, when pressure was lower than 20MPa, the suspension stability of compound fruit and vegetable juice improved along with the raising of homogenization pressure, when pressure is higher than 20MPa, suspension stability keeps constant substantially trend, and therefore, the suitableeest homogenization pressure of this compound fruit and vegetable juice is 20MPa.
(25MPa), feed temperature (20 ℃, 40 ℃, 60 ℃) and homogeneous number of times (1 time, 2 times, 3 times) carry out the orthogonal experiment (table 8) of three factors, three levels for 15Mpa, 20Mpa, determine the optimal conditions of homogeneous by measuring suspension stability with homogenization pressure.As seen from table, the secondary factors that influences homogenizing effect is respectively: homogenization pressure>feed temperature>homogeneous number of times.Best processing condition is: 40 ℃ Juice homogeneous 2 times under 20MPa, suspension stability is better.
The orthogonal experiment of table 8 homogeneous technology
The preparation technology of Pumpkin Juice of the present invention, pineapple juice, cider and 4 kinds of single juice of watermelon juice, be to adopt physical method, the pumpkin composite juice that processed has kept soluble components a large amount of in the raw material, comprise elements such as fructose, glucose, sucrose, malic acid, pectin and calcium, magnesium, potassium, and vitamin etc.In process of production, choosing fresh ripe pumpkin is raw material, guarantees the quality of pumpkin composite juice from raw material; Crushed pumpkin after the fragmentation is incubated a period of time under suitable temperature, can improves its crushing juice rate and suspension stability; Compound fruit and vegetable juice carries out high-temperature instantaneous sterilization, both can make the peroxide enzyme deactivation, can not produce cooked flavor again, can keep the local flavor of pumpkin composite juice, color and luster not to change effectively; Behind high-temperature instantaneous sterilization, in time the pumpkin composite juice is cooled off fast, be convenient to the centrifugal sediment of removing; In this Juice, add xanthans behind homogeneous, improve the stability of pumpkin composite juice.
Embodiment 1
(1) choosing ripe fresh pumpkin cleans, removes the peel, goes flesh, fragmentation and making beating to make crushed pumpkin, between 40 ℃~60 ℃, be incubated 1~2h, filter with 60~80 order vibratory sieves, filtrate is carried out the instantaneous enzyme that goes out of high temperature under 90 ℃~99 ℃, enzyme time of going out is 5~10s, cool to room temperature obtains Pumpkin Juice rapidly;
(2) choosing ripe pineapple, apple and watermelon is raw material, cleans, removes the peel, goes flesh, fragmentation and making beating to make aquatic foods and squeeze the juice;
(3) will be cooled to 15 ℃ through the fruit juice of the instantaneous enzyme that goes out of high temperature in 5s, centrifugal removal impurity, revolution are 4000r/min.
(4) Pumpkin Juice, pineapple aquatic foods are squeezed the juice, cider and watermelon aquatic foods squeeze the juice in 0.40~0.60: 0.21~0.35: 0.12~0.17: 0.07~0.13 ratio is carried out compound, fully mixes.
(5) behind interpolation 0.02% xanthans and 0.06% pectin, be incubated to 40 ℃ in the pumpkin composite juice, homogeneous is 2 times under 20MPa, obtains the pumpkin composite juice of stable homogeneous.
(6) with the pumpkin composite juice at 65 ℃~75 ℃, vacuum is vacuum outgas under 0.06~0.08Mpa, then at 121 ℃ of high-temperature short-time sterilization 5~10s, aseptic canning, is sealed in and promptly obtains finished product pumpkin composite juice in carton or the Plastic beverage can.
Embodiment 2
(1) choosing ripe fresh pumpkin cleans, removes the peel, goes flesh, fragmentation and making beating to make crushed pumpkin, between 40 ℃~60 ℃, be incubated 1~2h, filter with 60~80 order vibratory sieves, filtrate is carried out the instantaneous enzyme that goes out of high temperature under 90 ℃~99 ℃, enzyme time of going out is 5~10s, cool to room temperature obtains Pumpkin Juice rapidly;
(2) choosing ripe pineapple and watermelon is raw material, cleans, removes the peel, goes flesh, fragmentation and making beating to make aquatic foods and squeeze the juice, wherein 100% cider that is reduced into concentrated apple juice of cider;
(3) will in 5s, be cooled to room temperature through the fruit juice of high-temperature short-time sterilization after, supernatant is got in natural sedimentation.
(4) Pumpkin Juice, pineapple aquatic foods are squeezed the juice, cider and watermelon aquatic foods squeeze the juice in 0.40~0.60: 0.21~0.35: 0.12~0.17: 0.07~0.13 ratio is carried out compound, fully mixes.
(5) in the pumpkin composite juice, add 0.02% xanthans and 0.06% pectin after, be incubated 40~50 ℃ after under 20MPa homogeneous 2 times, obtain the pumpkin composite juice of stable homogeneous.
(6) with in the pumpkin composite juice behind homogeneous bottling or the pop can (250ml) in 85~90 ℃ of water-baths exhaust 10min, sealing, at 100 ℃ of sterilization 20min, be cooled to room temperature after, the pumpkin composite juice gets product.
By the pumpkin composite juice that above method makes, be 100% pure natural turbid liquid, wherein containing soluble solid is 6.5~7.0Brix, organic acid content is 0.50%~0.64%.Pumpkin composite juice of the present invention has the local flavor and the suitable mouthfeel of pumpkin, and color and luster is close with fresh pumpkin pulp, no precipitated and separated phenomenon, and no cooked flavor does not contain anticorrisive agent, is pure natural fruit and vegetable juice.The insulation processing method that the present invention adopts, the Pumpkin Juice that obtains has not only reduced the influence of enzyme preparation to the food nutrition health, has also kept the nutritional labeling in the fruit and vegetable materials simultaneously, makes the pumpkin composite juice of producing be of value to the healthy of drinking person.