Fresh cut fruits and vegetables processing technology

1 Selection of raw materials

Fruit and vegetable raw materials are the basis for ensuring the quality of fresh-cut fruits and vegetables. Fruit and vegetable raw materials generally choose fresh, full, moderate maturity, no odor, no pests and diseases of the individual.

2 Timely harvesting

Fresh-cut fruit and vegetable raw materials are generally harvested by hand, harvesting needs to be processed immediately. If the harvest can not be timely processing of fruits and vegetables, generally need to be refrigerated at low temperatures to spare.

3 Grading, trimming

Grading according to size or maturity, grading at the same time to eliminate raw materials that do not meet the requirements. For the production of fresh cut fruits and vegetables after the selection of raw materials need to be appropriate grooming, such as peeling, rooting, de-core, remove inedible parts.

4 cleaning, cutting

Washing can wash away sediment, insects, pesticide residues, etc., can be the next step to reduce bacteria, sterilization and improve the cleaning effect to lay a good foundation. According to the characteristics of raw materials and production needs, cleaning effect can be used to enhance the cleaning effect of dipping or aerating methods.

The size of freshly cut fruits and vegetables will have an impact on the quality of freshly cut fruits and vegetables. The greater the degree of cutting, the more serious injury caused by breathing; cut the smaller the volume, the larger the cutting area, the faster the surface moisture transpiration, the phenolic substances flowing out of the cutting surface is easy to be oxidized, browning occurs, affecting the appearance of the quality, but also not conducive to the preservation of the product. Different cutting methods will also cause cutting fruit traumatized by the size of the difference between the size of the area and the loss of nutrients, thus affecting the preservation effect of cutting fruit.

In addition, the knife blade condition and the preservation of cut fruits and vegetables has a great relationship with the preservation of time, sharp knife cut fruits and vegetables preserved for a long time; blunt knife cutting surface more injuries, easy to cause discoloration and corruption. The size of the cut on the quality of fresh cut fruits and vegetables also has an impact, the smaller the cut, the larger the incision area, the more unfavorable preservation.

5 Sterilization

Thorough cleaning of fruits and vegetables is the key to processing, by cutting the surface of fruits and vegetables has caused a certain degree of damage, juice seepage, easy to cause corruption, discoloration, resulting in a decline in product quality. Different fruits and vegetables can choose different cleaning solutions to maintain their food quality and extend their shelf life.

6 color protection and rinsing

Generally, after peeling or cutting and washing, cleaning water must meet the drinking water standards and preferably below 5 degrees Celsius. Fruit fresh cut, the biggest problem affecting its quality is browning. Generally in the cleaning water to add some color preservation agents such as sulfite, ascorbic acid, citric acid, potassium sorbate, sodium benzoate, cysteine, CaCl2, ZnCl2, calcium lactate can reduce the number of microorganisms and prevent the enzyme reaction, and thus can improve the shelf life and the product's organoleptic quality.

Rinsing after cutting is very effective in slowing down the physiological decay of fruit tissues and preventing fruit softening and quality changes. Rinsing is conducive to the release of substrates and enzymes from wounded tissues, usually for 1~5min. the effect of temperature on the rinsing effect is very obvious, high-temperature rinsing effect is better, but high temperature will increase the enzyme activity of polyphenol oxidase (PPO). Generally, the rinsing temperature should not be higher than 20℃. The rinsing effect also depends on the pH value, acidic environment has antibacterial properties, so generally use a lower pH value. Sometimes a rinse solution with a pH value close to neutral is required, such as the use of cysteine color protection treatment, otherwise it will lead to the fruit tissue to become peach.

7 Drainage

Rinsing must be strictly dried to avoid fruit and vegetable spoilage, at least the use of draining method to remove water from the surface of fruits and vegetables, can also be used to remove water from the surface of the product with a dry cotton cloth or blowing air.

8 Packaging

Packaging can effectively reduce the cutting of fruits and vegetables moisture loss, reduce the impact of external gases and microorganisms, inhibit respiratory strength, delay the generation of ethylene, reduce the speed of physiological and biochemical reactions, to prevent the volatilization of aromatic components, thereby delaying the cutting of fruits and vegetables, tissue aging and deterioration of corruption, and improve the quality and stability of the product. Fresh cut fruits and vegetables have a variety of packaging, common ways to spontaneous regulation of gas packaging (MAP), decompression packaging (MVP), active packaging (AP), film-coated packaging and so on.

9 Storage

Temperature is the main factor affecting the quality of fresh-cut fruits and vegetables. Fresh-cut fruits and vegetables in the production, storage and transportation and sales process should be in a low-temperature state. The best storage temperature is slightly above the freezing point of fruit and vegetable material temperature; can also be used according to commercial needs, 5 ℃ or 10 ℃ shelf temperature to store fresh-cut fruits and vegetables. In addition, the storage of attention should not be lower than the cold temperature of fruits and vegetables, in order to avoid cold symptoms, resulting in fresh-cut fruits and vegetables can not be eaten. Packaging and storage process comprehensive utilization of various preservation measures, can maintain the edible quality of fresh cut fruit, extend the shelf life.