The in vitro rate of hydrolysis was measured using hog pancreatica-amylase, according to Holm, Bjorck, Asp, Sjoberg, and Lundquist (1985). A 50 ml aliquot of phosphate buffer (pH 6.9)was added to a portion of each type of spaghetti containing 500 mg of digestible starch. Samples were incubated at 37°Cinashaking water bath. In the first 5 min before the addition of enzyme aliquots of 0.2 ml of each sample were taken to mark as time zero. After an interval of 1 min, 1 ml of a solution containing 40 mg of porcine pancreatic แอลฟ่า-amylase (A-3176) in 1 ml of phosphate buffer was added to each sample. Samples (0.2 ml) were with-drawn after 5 min and every 15 min for 1 h. These samples were added to tubes than containing 0.8 ml distilled water and 1 ml of 3,5 dinitrosalicylic acid (DNS). Samples were incubated at 100°C in a water bath for 10 min. Then 15 ml of distilled water was addedto each tube and mixed well. The reducing sugars released were measured at 530 nm in parallel with a standard curve of maltose.The rate of hydrolysis was expressed as the percentage of digestible starch hydrolysed at different times.