DEODORIZATION OF RAW MILK IN A ROTARY SPRAY APPARATUS

Dairy products must correspond to a number of organoleptic and physico-chemical requirements. Organoleptic characteristics are smell and taste because they primarily affect the demand of consumers. The most common defects of raw milk affecting the quality of dairy products particularly during the storage are smell and taste of feed origin. The reason for this is the use of feed containing specific substances passing into dairy products. Dairy products containing fat easily absorb substances that give foreign smell and taste from the environment. Therefore, apart from feed defects dairy products can acquire other foreign smells and tastes. To correct the defects of dairy products deodorization is used. The essence of the deodorization process is the processing of hot raw milk under vacuum conditions. Most odorizing substances form azeotropic mixtures with water vapor. The boiling point of the resulting mixture is below the boiling temperature of water. This enables to conduct the steam distillation of odorizing substances from raw milk. The main drawback of the existing deodorizers is low specific productivity of the apparatus volume. To eliminate this fault rotary spray device with high intensity of processes can be used. A distinctive feature of the rotary spray device is multiple fluid circulations accompanied by dispersing and strokes of drops on the liquid film on the surface of demister and housing. This enables to achieve the desired efficiency of the process, and by selecting the appropriate circulation frequency one can widely adjust deodorization time. The effectiveness of milk deodorization with reproduced defects of smell and taste has been studied and rational parameters of the process have been established. After deodorization the physico-chemical parameters have been determined and organoleptic evaluation of deodorized milk has been carried out. Preparation and conducting the smell and taste assessments were carried out according to regulatory documents. A layout of upgraded pasteurization and cooling unit for obtaining pasteurized milk with a vacuum deodorization of raw materials has been proposed.