Applications of enzymes in food processing
Processed foods provide convenience, improved shelf-life, increased palatability and offer variety in the diet. Several processing techniques – physical and chemical- are used for obtaining the finished product. Chemical methods are harsh and affect the quality of the product adversely. Enzymes offer an alternative to chemical catalysis as they work under mild conditions of pH and temperature.
Enzymes are proteins, which catalyze and reduce the energy threshold requirements for chemical reactions. They function at the molecular level on substrates such as carbohydrates, proteins and fats. After modification of the substrate, the enzyme remains unchanged. Enzymes are the unique natural processing aids in the food and beverage industry.
Enzymes present in the raw material can, along with processing, affect the functional and nutritional properties of the final product. They are used for developing new food ingredients and products, recovery of the by-products as well as improving food quality through improved nutrient availability, flavor and texture. Intrinsically present enzymes can be detrimental to food quality through enzymatic browning by such enzymes as polyphenolases and rancidity due to the action of lipoxygenases and lipases. Food spoilage, through enzyme produced by spoilage microorganisms, are also of concern as the shelf life of the food is affected. Controlling enzymatic activity is critical during food processing as enzymes have both beneficial and detrimental effects. Knowledge on enzyme stability under the relevant processing conditions is required for process design (e.g. its thermostability, resistance towards acid environment). In case of detrimental enzymatic action, elimination or retardation of the enzymatic reaction is performed by inactivation of the enzymes either by physical methods (e.g., heating, blanching) or by chemical additives.