ENZYMATIC-HYDROLYSIS OF BARLEY STARCH LIPIDS

The efficiency of phospholipase and lipase preparations in the hydroly sis of lysophospholipids of native and gelatinized barley starch was e xamined. The degree of hydrolysis was analyzed by determination of the amount of released fatty acids by an enzymatic method. Thermal and st ructural properties of the enzyme-treated starch were studied by diffe rential scanning calorimetry and light microscopy. Lysophospholipids o f the gelatinized barley starch were easily hydrolyzed, in contrast to the lipids of the granular starch. The maximum degree of hydrolysis a chieved for the gelatinized starch was 80% and for the native starch a pproximate to 20%. Gelatinization enthalpies and micrographs indicated that even though the amount of the released fatty acids from the nati ve starch was small, formation of free fatty acids inhibited swelling and gelatinization of starch granules.