Compared to the discoloration of frozen fruits and vegetables produced by crispy fruit and vegetable manufacturers, it can occur during the production and processing stage, as well as during the frozen storage and circulation stages. Mainly due to the action of microorganisms, and the growth and reproduction of microorganisms require a comfortable temperature area. Above or below this temperature will promote the inhibition, cessation, and even death of microbial life activities. And frozen fruits and vegetables use artificial refrigeration technology to reduce the temperature of fresh vegetables, which can greatly inhibit microbial activity and enzyme activity, and can to some extent avoid spoilage.

Manufacturers of crispy fruits and vegetables often experience changes in color, flavor, and nutrition in frozen foods such as frozen fruits and vegetables. Before freezing, frozen fruits and vegetables use measures to inhibit or inactivate enzyme activity, thereby reducing changes in product quality caused by the presence of enzymes.

However, at present, frozen fruits are mostly processed, and there may be discoloration phenomena such as light colored fruits and vegetables or sliced fruits and vegetables turning red or black in color, green fruits and vegetables gradually losing their green color and turning gray green, fruits and vegetables products losing their original color or deepening their original color. The main reason is that fruits and vegetables contain polyphenol oxidase enzymes, which oxidize phenols into red and black quinone compounds under the action of oxygen, and chlorophyll enzymes oxidize and decompose chlorophyll.

In addition, the presence of acidic substances in the production and processing water of fruit and vegetable crispy manufacturers can also cause product chlorosis, and metal ions can catalyze product browning. Refrigerant leakage can also cause discoloration. So in order to ensure the quality of frozen fruits and vegetables, it is necessary to pay attention to each step during the production and processing of frozen fruits and vegetables, strictly follow the standards, and not take any details lightly.