Sapiga V. Improvement of the technology of ice cream with vegetable raw materials

The dissertation is devoted to the improvement of the technology of ice cream with vegetables due to the preliminary activation of the functional and technological properties of vegetable raw materials, the development of the formulation of new types of ice cream with natural ingredients, and the clarification of the technological modes of its production. The choice of polyfunctional vegetable raw materials for the formation of a complex of sensory, physicochemical and microbiological quality indicators of milk-vegetable, vegetable and sherbet ice cream, was scientifically explained. The technological expediency of preliminary activation of puree from table carrots, table beets, broccoli, zucchini and tomatoes by partial destruction of protopectin in various ways before adding them to the mix for the production of ice cream has been proven. The higher efficiency of enzymatic hydrolysis of protopectin in vegetable purees was revealed, compared to acid hydrolysis, which allows increasing the yield of soluble pectin by 8-12% with lower energy costs in 1,15…1,25 %. The parameters of the process of protopectin enzymolysis were optimized according to the degree of its hydrolysis (not lower than 90%) for various types of vegetable raw materials with the content of pectin substances from 0.22 to 2.56%. Partial loss of functional and technological properties of vegetable raw materials due to excessive hydrolysis of pectin substances has a negative effect on the rheological characteristics os ice cream mixes. Fermented vegetable raw materials due to the higher content of soluble pectin and the formation of structuring complexes between polysaccharides and milk proteins, significantly affect the rheological characteristics of milk mixes. The effective viscosity of the practically intact structure of milk-vegetable mixes with vegetable purees hydrolyzed by an acid method is somewhat lower than mixes with fermented purees, which is explained by the thinning effect of pectinase on fragments of plant cell membranes. It was showed that, compared to milk-protein concentrates, oat β-glucan exhibits higher technological activity in the composition of ice cream mixes, including its combination with soluble pectin of vegetable puree. t has been proven that the effective viscosity of ice cream mixes with oat β-glucan in the amount of 0.5…1.0% is in the range of recommended values. he complex use of β-glucan and fermented vegetable purees with a high content of soluble pectin and the presence of softened vegetable fibers allows improving the viscosity-speed characteristics of mixes: the effective viscosity increases by 11.5…15.9%, and the degree of recovery by an average of 10%. A correlation between viscosity, water activity and surface tension of low-fat ice cream mixes was revealed, which is explained by intermolecular interaction between macromolecules of hydrocolloids and active binding of free water by a complex of low- and high-molecular compounds. An alternative substitute for the Cremodan SI 320 stabilization system in the amount of 0.5% in low-aft dairy ice cream is a complex of natural ingredients such as oat β-glucan and fermented purees in amounts of 0.5 and 15…25%, respectively. The functional and technological properties of pectin-containing purees from vegetables in the composition of ice cream with their varied content in the range from 10 to 35% were studied. The sensory indicators, content of soluble pectin, water activity and active acidity of milk-vegetable mixes, overrun and resistance to melting of milk-vegetable ice cream were selected as quality criteria of the studied samples. It was showed that the hydrolysis of protopectin reduces the water activity in vegetables and milk-vegetable mixes, according to the total content of soluble pectin. It has been proven that in a given content range, the solids of vegetables increase the resistance to melting of ice cream. Based on the comparative analysis of the research results, recommendations were developed for the preparation of basic (typical) formulations of milk ice cream with vegetables, sherbet and vegetable ice cream, taking into account the rational ranges of content of fermented vegetable purees, including the combination of different types of vegetables. The technological modes of maturation of ice cream mixes with vegetable raw materials of different chemical composition have been specified. The normative indicators of the quality of milk ice cream with vegetables, vegetable ice cream and sherbet, including during storage, were studied. The reliability of the obtained results was confirmed by the use of modern research methods, appropriate equipment, and the use of mathematical tools for processing the results. Scientific provisions and recommendations are confirmed by laboratory studies conducted in the laboratories of universities in Ukraine and Poland.