Page 386 - Demo

390 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYAdditionally, with a fixed amount of enzyme, increasing the substrate concentration initially raises the enzyme activity. However, further increases in sample amount do not increase enzyme activity as all enzyme active sites become saturated.The results indicated that pH = 6 is optimal for both amylase and amyloglucosidase enzyme activity. At pH = 4, the activities of %u03b1-amylase and amyloglucosidase are significantly inhibited. This leads to incomplete hydrolysis of digestible starch, leaving some digestible starch in the sample and increasing the measured resistant starch content. At pH = 5, in a mildly acidic environment, amyloglucosidase can still function but not at optimal efficiency, while %u03b1-amylase activity is reduced compared to neutral pH. This may result in a slower hydrolysis process, causing incomplete breakdown of digestible starch and a slight deviation in resistant starch content. At pH levels of 7 and 8, the properties of resistant starch may be altered, with the resistant starch structures breaking down and losing their resistance to enzymatic activity, making them more susceptible to enzyme action during hydrolysis. This leads to a reduction in the measured resistant starch content.Method ValidationThe analytical procedure was applied to samples with resistant starch content ranging from low to high, and it provided repeatability values that meet the requirements set by AOAC. The corresponding value for the CRM sample also demonstrated the reliability and stability of the method for analyzing resistant starch content in food products.The results obtained in Table 8 showed that the method for determining resistant starch content meets the intermediate precision requirements of AOAC and is suitable for implementation in food safety testing laboratories.