Enzymatic Activities and Fermentation Products of Lactic Acid Bacteria From Fruits and Fermented Beverages. Incidence on Food Quality

Abstract

Growth and metabolism of lactic acid bacteria (LAB) are essential in the fermented foods quality. In fermented beverages like ciders and wines, LAB convert l-malic acid to l-lactic acid during malolactic fermentation (MLF). Other carbon sources as glycosides may be utilized by LAB modifying their quality. Actually, consumers demand for minimally processed foods. Lactic acid fermentation may be an important biotechnology for improving safety, nutritional, sensorial, and shelf-life properties of by-product fruits. Dominant microbiota of tomatoes constituted by obligate heterofermentative LAB inhibited the natural microbiota developed in tomato puree at 30 °C. In addition, Lactobacillus plantarum survived at high cell density in orange juice at 4 °C for prolonged period, without modifying its organoleptic properties. This determines the oranges suitability as raw material for biopreserved functional juice manufacture. On the other hand, Oenococcus oeni strains from wines diverted carbon flux of glucose-citrate cometabolism to essential amino acids biosynthesis under nutritional deficiency. Their glycosidase activities in cell suspension highlighted the MLF contribution toward flavor enhancement in winemaking. Finally, biogenic amine (BA) formed by precursor amino acid decarboxylation through microbial enzymes can affect the sanitary quality of food.