Study of microbiological background of herbal ingredients and dairy-vegetable compositions

Abstract

The rates of microbiological safety of powdery vegetables, vegetable-milk compositions, compound desserts have been studied. No pathogenic germs (incl. salmonella), Escherichia coli, yeast, nonspore-forming bacteria B cereus have been detected in powdery vegetable samples. The number of mesophilic aerobic and facultative anaerobic microorganisms as well as amount of molds does not exceed safety index normalized by the legislation. Proteolytic microorganisms compose the basic microflora of powdery vegetables. Microbiological background of vegetable and milk basis is characterized by the presence of microorganisms differed by different resistance to the medium conditions – рН value, presence of oxygen and high temperatures impact. Enrichment of milk base by vegetable components necessitates to adjust the thermal effect regimes prescribed for milk treatment without additional ingredients. Introduction of vegetable ingredients into milk base is accompanied by polysemantic effect of high temperatures on microorganisms of polycomponent milk – vegetable base. On the one hand introduction of vegetable raw material into milk enhances inhibitory temperature effect on microbial cells due to transition of the medium рН into sour side; on the other hand presence of vegetable raw material particles protects microorganisms against sensitive effect of high temperature. Microflora of vegetable-milk compositions after heat treatment as well as ready-made desserts on their base was presented by spore-forming bacillus the number of which is correlated by their number in the initial raw material. In order to choose the optimal regime of heat treatment all processes running during heat treatment and particularly microbiological and physical-chemical degradation of polysaccharides of vegetables cell structures.