Development of technology of fermented milk drinks enriched with dietary fibers

Abstract

The dissertation substantiates the principles and methods that form the scientific basis for the enriching of fermented milk drinks with dietary fibers. Fermented milk drinks are products having certain functional properties according to their chemical composition. They contain proteins, fats, carbohydrates, vitamins A, D, C, E, groups B, H, PP, minerals (K, Ca, F, Cu, Sn, Sr, Mg, Al, Co, Mo), amino acids and beneficial lactic acid microflora. The recommended amount of their daily consumption is 500- 750 ml. Among all dairy products produced in the world, the share of kefir production is almost 65%. This product contains all the nutrients the body needs, except for dietary fibers. According to the theory of rational nutrition the value of food is represented in providing the body with necessary nutrients and its ability to self digest in the human stomach and at the same time be food for those microorganisms that inhabit the intestines and supply our body with the necessary substances. This property is inherent in dietary fiber (ballast substances) that are not part of kefir. Since there are no enzymes in the gastrointestinal tract that break down the fibers, the latter reach the large intestine unchanged. Intestinal bacteria have enzymes that can metabolize fibers. Due to fermentation, they obtain energy for the reproduction and construction of new cells. Thus, by enriching fermented milk drinks with dietary fiber, in an amount consistent with the recommended daily need for their consumption, it is possible to create a fermented milk drink that will be as balanced as possible in the content of all vital nutrients, including ballast substances. The purpose of the study is to increase the nutritional value of fermented milk drinks by introducing recycled raw materials containing dietary fiber into their composition. The object of the research is the technology for the production of fermented milk drinks with plant supplements. The subject of the study: whole milk; defatted sesame flour; rice bran; model samples of fermented milk drinks enriched with dietary fibers. The research methodology is based on the chemical composition analysis of raw materials. According to the results of the analysis of the information available in modern literature, a scientific hypothesis is formulated, which is substantiated in the theoretical part of the study and confirmed in the course of experimental research. During the experimental research, traditional methods of analysis of the subject of research such as physicochemical, microbiological, organoleptic, antioxidant were used. The microbiological composition of products and their storage capacity were analyzed. The influence of dietary fibers on the main properties of products has been established. According to the materials of the research and the results obtained, the technology for production of fermented milk drinks with the dietary fibers content based on recycled raw material (sesame flour, rice bran) is developed and scientifically grounded. The first section of the dissertation analyzed the types of raw materials and additives used in the production of fermented milk drinks, modern methods of production of fermented drinks. The functional properties of the components of fermented milk drinks were studied. The functional and therapeutic and preventive properties of fermented milk drinks have been proven by numerous scientifically based facts. The second section presents the methodology and research methodology. The content of methods of research of organoleptic, physicochemical, microbiological, antioxidant properties of products, the content of vitamins and dietary fibers in them is disclosed. The experimental part of the work was carried out in the laboratory conditions of the School of Food Sciences of the Henan Institute of Science and Technology (China). The developed product was approved industrially on the basis of the craft enterprise for processing milk of the individual entrepreneur D.V. Opryshko. The third section describes the results of the study of the influence of the proposed additives on the product properties. Fermented milk drinks with the addition of defatted sesame flour in the amount of 0, 2%, 4%, 6%, 8% were studied during 28 days of storage. Organoleptic properties, microbiological viability, physicochemical properties (total titrated acidity, water-holding capacity, apparent viscosity and pH), antioxidant activity (DPPH radical activity and ·OH radical activity). It was shown that the addition of defatted sesame flour in the amount of 2% had a positive effect on the following indicators: the content of proteins, fats, dietary fibers, pH, total titrated acidity, apparent viscosity, antioxidant activity, water-holding capacity. Microbiological analysis showed that dietary fiber of sesame flour is a good environment for the development of lactic acid microflora. The introduction of defatted sesame flour increases the therapeutic and preventive properties according to the results of DPPH radical activity and ·OH radical activity. Fermented milk drinks with the addition of rice bran in amounts of 0, 0.1%, 0.3%, 0.5%, 0.7% were studied during 28 days of storage. Organoleptic, physicochemical (total titrated acidity, water-holding capacity, apparent viscosity and pH), microbiological properties, antioxidant activity (activity of DPPH radicals and activity of ·OH radicals) were analyzed. The introduction of rice bran showed a positive effect on these parameters. The fermented milk drink with the addition of rice bran in the amount of 0.1% showed higher sensory evaluation. The recommended shelf life of fortified fermented milk drinks is 14 days. Such results give reason to claim that fermented milk drinks with sesame flour and rice bran can be used for functional nutrition. The fourth section contains the results of optimization of consumption properties and developed recipes of fermented milk drinks with the addition of defatted sesame flour, rice bran by building a mathematical model, namely: choosing the objective function, setting the boundary conditions and determining the rational parameters of this mathematical model. The fifth section of the dissertation discovers the recommendations as regards to the implementation of the developed technologies under industrial conditions. The technological scheme was developed and optimum modes for performing of all technological processes were established. The technological equipment for the production of fermented milk drinks is offered.