ABSTRACT
Food processing comprise of techniques employed to transform raw ingredients into final food product or to preserve the food product. Rheological properties of foods are greatly influenced by various unit operations and processing methods or conditions such as heating and mechanical treatments. In order to design storage structures for foods and refrigeration equipment the knowledge of thermal properties is important. Rheological properties of fruit purees, juices and other fruit based products such nectars, ice creams and jellies which consist of pulp as raw ingredient are vital to study to elucidate the effect of processing on the crucial quality parameters of the final product. Different thermal processing techniques such as pasteurization, sterilization, balancing and retort have been largely used for food processing industry to maintain undesirable enzymes, microorganisms, and bacteria in food. In freeze drying for dairy products a process called Lyophilisation used to freeze the product, where by using high-pressure vacuum water is extracted in vapour form.
