Fruits and vegetables still have a lot of field heat after being picked. This heat guides the critical growth and rapid aging of plants. This heat is also coordinated with the release of trace elements in the moisture exposed by the mechanical damage left by the picking or processing of vegetables and fruits. Accelerate the discoloration of fruits and vegetables, and coordinate with the moisture on the surface of fruits and vegetables to nourish a large number of fungi and quickly corrupt the body of fruits and vegetables.
Therefore, no matter what kind of fruit or vegetable, the most important step in keeping fresh is to quickly and evenly eliminate field heat, which is what we usually call pre-cooling. Completing the pre-cooling in the first time also laid a solid foundation for the preservation of fruits and vegetables.
Of course, pre-cooling is not enough. The excess water on the surface of fruits and vegetables is an important root for nourishing fungi. The mechanical wound of fruits and vegetables is an accelerated area of discoloration of fruits and vegetables. The continued growth of fruits and vegetables after picking is the root cause of the aging of fruits and vegetables. These are problems that need to be resolved.
What are the methods of pre-cooling? What are their advantages and disadvantages? Below ZKGY will introduce you one by one, including:
1. Cold air precooling;
2. Cold water precooling;
3. Ice precooling;
4. Forced-air differential pressure pre-cooling
5. Vacuum precooling