The starch content in most fermented vegetables is limited, hence the amylolytic ability of lactic acid bacteria is a characteristic with little demand. Although hydrolyzing starch to simple sugars is not important in traditional fermented vegetables, a few amylolytic lactic acid bacteria have been isolated from starchy raw materials. An investigation of Mexican pozol, a fermented maize dough, indicates that lactic acid bacteria accounted for 90-97% of the total active microflora. Strains of lactic acid bacteria were isolated and identified, including Leu mesenteroides, Lb. plantarum, Lb. confusus, L. lactis, and L. raffinolactis (49). From sour cassava starch fermentation, Lb. plantarum and Lb. manihotivorans were isolated. Lb. manihotivorans grows and converts starch into lactic acid more rapidly and efficiently than Lb. plantarum (50,51). Durinh fermentation, these amylolytic lactic acid bacteria degrade the starch first, and then the resulting sugars allow a secondary flora to develop. An acidophilic starch hydrolyzing enzyme secreted from a strain of L. plantarum was isolated and partially purified. This enzyme has a molecular mass of approx. 230 kDa and is capable of hydrolyzing soluble starch, amylopectin, glycogen, and pullan. The major reaction products from soluble starch were maltotriose, maltotetraose, and maltopentaose. These reaction products suggest that this enzyme may hydrolyze both a-1,6- and a-1,4-glucosidic linkages (52).
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