Application of Enzymes in Fruit and Vegetable Processing and Preservation

Enzymes often used in fruit and vegetable processing include pectinase, cellulase and amylase, etc. The use of them for raw material processing can fully release the contents of the cells, thereby improving the sensory characteristics of the product and increasing yield. In the fruit and vegetable preservation process, enzymes can remove or mitigate the damage of oxygen in the food to the quality of fruits and vegetables to extend the shelf life, and some biological enzymes can kill or inhibit the reproduction of bacteria to achieve the effect of preservation. The common preservation enzymes are mainly glucose oxidase, lysozyme, etc.?

1. Application of enzymes in fruit and vegetable processing

Enzymes have mild conditions of action, strong catalytic function, good specificity, easy control of the reaction, can avoid violent reactions, maintain the color, flavor and structural stability of the food itself, does not affect the appearance, texture and taste of fruits and vegetables, will not lead to spoilage, destruction and other problems. Fruit and vegetable processing is a very complex process, in the processing process by using enzymes to remove substances that affect the quality of fruits and vegetables, such as starch, pectin and cellulose, etc., while also paying attention to retaining dietary fiber, vitamins and sugars and other nutrients in fruit and vegetable materials to ensure the color and flavor quality of processed products.

1.1 Pectinase

Pectinase is mainly contains polygalacturonase (PG) and pectin esterase (PE), which can degrade the pectin substance, so that the pectin substance in the juice can be rapidly decomposed and the viscosity of the juice can be reduced. Due to the decomposition of pectin, the turbid particles lose the protection of colloid and flocculate each other, thus improving the clarification effect. At present, it has been widely used in the processing of orange juice, apple juice and other juices, which can reduce the content of colloid in fruit and vegetable juices, make the juice easy to clarify, increase the aroma of juice, reduce the production of fruit residue, and improve the quality of juice. Pectinase in fruit wine brewing uses its flocculation effect to make the polymers settle, allowing the raw materials of fruit wine to be fully impregnated, improving the color, aroma and clarification of fruit wine, and enriching the taste of fruit wine.

1.2 Cellulase

Cellulose is a polymeric polysaccharide molecule made from glucose linked by β-1,4-glucosidic bonds. Cellulose has a high degree of polymerization and a hard structure, which locks the cell contents and prevents intracellular sap from escaping. Cellulase is a general term for a group of enzymes that can hydrolyze cellulose β-1,4-glucosidic bonds, turning cellulose into cellobiose and glucose, and it is not a single enzyme but a multi-component enzyme system that acts synergistically. It is used to hydrolyze the cell wall, and the cell contents become easily extractable without the support and protection of the cell wall.

1.3 Amylase

After fruit ripening, if not processed in time, the starch in fruits and vegetables accumulates continuously at low temperature for a long time, which easily causes the raw juice to be turbid and its stability decreases during processing and affects the overall sensory. Amylase reduces the starch content in fruit and vegetable juice by degrading polysaccharide substances, making the juice easy to clarify, improving the juice yield, reducing production costs and achieving good economic benefits.

2. Application of enzymes in food preservation

During the preservation process, food is affected by oxygen, microorganisms and temperature, which destroy the stable structure of food and make the quality of food change and reduce the value of food. The traditional chemical preservation methods cause more nutrient loss of food and are not conducive to food preservation and processing. Enzyme engineering as a new type of health preservation technology has gradually entered people's view. Biological enzyme preservation is mainly through certain enzymes with specific binding function and enzymes in food at specific binding sites, thus reducing the activity of enzymes in food, inhibiting or reducing their reaction rate, providing a favorable environment for food and extending the shelf life of food.

2.1 Glucose oxidase

In the process of storage and transportation, fruits and vegetables are susceptible to a series of chemical reactions due to the effect of oxygen, causing changes in color, aroma and taste, and most of the bacteria reproduce and grow due to the presence of oxygen, accelerating food spoilage and deterioration. As a natural and safe, fast and efficient food preservation agent, glucose oxidase can effectively delay or stop the oxidation and deterioration of fruits and vegetables, curb browning and extend the shelf life of fruit juice.

2.2 Lysozyme

Lysozyme mainly acts as a glycosidic hydrolase of the β-1,4 glycosidic bond between N-acetylcytidylic acid (NAM) and N-acetylglucosamine (NAC). By acting on the peptidoglycan of the bacterial cell wall, it causes the cell wall insoluble mucopolysaccharide to break down into soluble glycopeptides, leading to the escape of the contents of the cell wall rupture, resulting in cell death due to rupture caused by osmotic pressure imbalance.

Lysozyme can directly bind to negatively charged viral proteins and form complex salts with DNA, RNA, and decapentaplegic proteins, thus inactivating the virus. In addition, it kills viruses by activating the body's immune system and regulating lymphocyte- and macrophage-mediated cytotoxicity. Lysozyme on the common microorganisms in life, viruses, etc. have inhibitory effects, to fruits and vegetables in appropriate amounts of spray lysozyme, can effectively kill the surface residual bacteria, extend the shelf life of fruits and vegetables.

2.3 The use of enzymatic browning mechanism to create enzyme inhibitors to achieve Fruits and vegetables preservation

The use of enzymatic browning mechanism to achieve freshness of fruits and vegetables is mainly through the inhibition of polyphenol oxidase activity to reduce the occurrence of browning. The rapid and intense catalysis of polyphenol oxidase (PPO) in fresh living tissues leads to the production of browning substances, which greatly affects the appearance of fruits and vegetables and the nutritional value of the finished product, and reduces consumer acceptance.

Yotabio is a leading specialist in natural shelf-life solutions & enzymes. We produce natural shelf-life ingredients and enzymes to service food & beverages. We are committed to maintaining a diverse portfolio to meet our clients’ needs, reduce spoilage and food waste, and contribute to the safety of food.