Fruit and vegetable juice contains a lot of water, sugar, malic acid, citric acid, tartaric acid, fruit juice also contains a small amount of tannin and protein, minerals, including calcium, phosphorus, potassium, sodium and so on. Pigments include carotenoids, anthocyanins and so on. Also contains a small amount of heat-sensitive substances and aromatic substances. Only to fully grasp the composition of fruit and vegetable juice and its characteristics, can be processed in the fruit juice production
process flexible application of various techniques to destroy the original fruit juice nutrition, color, flavor, aromatic links to intervene in order to maximize the juice The original quality of the final product.
Juice is generally divided into clear juice and mixed fruit and vegetable juice, common clarification of fruit and vegetable juice with apple juice, pear juice, grape juice, melon juice, blueberry juice, blackberry juice and so on; mixed fruit juice orange juice, tomato juice, carrot juice ; Fruit juice with fruit generally peach, apricot, plum, plum and so on. Juice processing process: pretreatment (sorting
, crushing, heat treatment) - juice - coarse filter - composition adjustment - fine filter - homogenization degassing - concentration - sterilization
In the pretreatment process should be noted that the pesticide residues more fruits and vegetables, cleaning can be added with dilute hydrochloric acid or fatty acid for treatment; for microbial contamination, can use a certain concentration of bleach or solution soak, and then clean water. After most of the fruit is broken, the juice must be preheated before the juice is used to soften the pulp tissue to increase the rate of juice. In addition, different preheating temperatures can promote or inhibit the activity of the enzyme, depending on the nature of the enzyme. , Temperature and the role of time, a direct impact on the final product color and flavor, so according to different market needs, we must grasp a different treatment process.
There are several ways to clarify the purpose of clarification in fruit juice, enzymatic, gelatin-tannin method, enzyme-gelatin method, diatomaceous earth method and so on. It is noteworthy that, in the use of enzymatic time, the general pectinase PH value of 4.5-5.0, the temperature is 50 degrees Celsius. If it is grape juice processing, but also to carry out a special addition to tartar. Adjust the juice mix, that is, the deployment process. Including the adjustment of sugar content, the determination of solid acid ratio, the addition of vitamins. So that the final product to a certain size, is the final product of nutrition, taste, color from the decisive step. In the production of turbid juice when the juice must also be homogeneous, to prevent solid-liquid separation, stratification, to promote the taste more delicate. In order to prevent the oxidation of fruit juice deterioration, the juice must also be degassed to remove the pre-treatment process mixed with a lot of oxygen, carbon dioxide and nitrogen. Concentration of fruit juice is generally concentrated by falling film, and the need for vacuum, low temperature, fast and efficient concentration, to ensure that these conditions to achieve the case, so that the maximum efficiency of the enrichment pot to reduce production costs. In the process of concentration, usually need to fruit aroma recycling, apple juice aroma recovery rate is generally 8% to 10%, grape juice and orange juice in 26% to 30%.
and filling, most of the clarification of fruit juice are hot filling, filling the product after the tunnel sterilization, generally 85 degrees Celsius ~ 95 degrees Celsius for 15 minutes to 30 minutes of sterilization. For the general use of high temperature sterile juice sterilization, because the opener juice heating time is too long to produce cooked taste, and the color and fragrance loss is relatively large. Sterilization quickly after cooling and then follow-up packaging.