The processing of frozen food includes three stages – pre-treatment, freezing, and frozen storage. Depending on the frozen food, pre-treatment may involve processes such as blanching, heat treatment, immersion treatment, and freeze protection. An effective freezing process can only maintain the existing quality of the food, but cannot improve it. Therefore, these pre-treatment processes are to maintain the quality and safety of frozen food.
For example, vegetables are usually blanched with steam or hot water to slow down the chemical and physical changes that may occur during storage. However, fruits are usually immersed in ascorbic acid or various sugar solutions to minimize browning. Meat products, fish, and some vegetables will undergo heat treatment to kill surface microorganisms and help them maintain their original nutrition and taste as much as possible after thawing.
The original product of quick-frozen food is pre-processed, and the next processing technology is quick-freezing. Freezing methods can also be divided into two categories according to different types of frozen foods-freezing separately before packaging and freezing after packaging.
IQF (Individual Quick Freezing) refers to each piece of food that is individually frozen before packaging. Common examples include fruits (i.e. blueberries or strawberries), vegetables (i.e. peas, corn, green beans), seafood (i.e. scallops or shrimps), poultry (i.e. a single chicken breast), or even whole poultry products, such as frozen turkey, are also processed under the IQF method. Products that are frozen after packaging refers to bulk frozen foods that have been packaged before freezing.
Although all these freezing methods are used in the frozen food processing industry, the most important thing for improving productivity is that companies need to design a set of comprehensive freezing equipment to adapt to all stages of the freezing process and to optimize the entire freezing system as a whole.
When goods are transferred between the freezer, cold storage, and refrigerated trucks, they must be temporarily stored at the low-temperature unloading terminal. The low-temperature unloading dock is a fully enclosed structure, which effectively controls the temperature in the unloading area. In this way, refrigerated trucks, low-temperature unloading docks, cold storage, and freezer storage form a constant temperature cargo storage space, which allows the cargo to be stored, handled, selected, and transported at a constant temperature, ensuring the integrity of the cold chain, thereby ensuring food safety and quality, and minimize product loss.