LACTIC ACID FERMENTATION OF MIXED JUICES OBTAINED FROM DIFFERENT VEGETABLES

Abstract

In present work were realised experiments oriented to preparation of lactic acid fermented juices usin g some vegetables in proportion established through s ensorial analysis. The processes were realised at 2 4 degrees Celsius for 96 hours, using lactic acid bacteria is olated from the microbiota of spontaneous fermentat ion of vegetables. During the lactic acid fermentation of juices the evolution of some sensorial and chemical parameters (soluble dry substance, reducing sugars, pH, lactic acid, amino acids, ascorbic acid, nitrites) was fo llowed. The metabolic processes of lactic acid bacteria wer e underlined by the dynamics of all the chemical parameters mentioned. At the end of the process the development of the undesirable micro organisms was observed also by the evolution of the chemical indi cators. After 96 hours of fermentation, the stabili ty of juices was higher, due of their lactic acid content, which was increased from 0,12 to 1,06g/100g. Also, the m inimum pH value was about 4,26. The quantity of reducing s ugars remained in lactic acid fermented juices was correlated with their initial content, respectively the final acidity. The dynamics of the amino acids content during the lactic acid fermentation of cocktails was underline d that the pre-digestion of proteins improve nutritio nal quality of the final products. The decreasing o f the nitrites content was considered significant for point out th e denitrification activity of lactic acid bacteria.