Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2000
Publication Date: 2/15/2001
Citation: Li, B.W., Blackwell, E., Behall, K.M., Elmstahl, L. 2001. Resistant starch & total dietary fiber content of oatrim muffins with different levels of amylose amylopectin, and b-glucan. Cereal Chemistry. 78:387-390. Interpretive Summary: The main objectives of this study is to determine starch and total dietary fiber content of 9 types of muffins made from oatrim with varying levels of beta-glucan and corn starch containing different amount of amylose and amylopectin using an official TDF Method with some modification. We also compared the values of resistant starch (RS) obtained from 2 other methods utilizing different enzymes and experimental conditions. The test muffins were from the same batches baked and fed to human subjects to study effects of starch composition and fiber content on carbohydrate and lipid metabolism in normal and overweight women. Previous controlled human feeding studies conducted at the Beltsville Human Nutrition Research Center (BHNRC) have found improved glucose and insulin responses after consumption of soluble oat fiber, high amylose cornstarch, and high fiber diets. Results from this study shows that a less labor-intensive and more cost-effective method can be used to determine the amount of total starch, resistant starch, and total dietary fiber in baked products; such as the muffins tested here. Presently, there is no official method for resistant starch measurement.
Technical Abstract: Nine types of muffins made with 3 levels of beta-glucan and 3 amylose/amylopectin ratios were prepared at the Beltsville Human Nutrition Research Center, USDA. They were fed to human subjects to study effects of starch composition and dietary fiber content on the carbohydrate and lipid metabolism in normal and overweight women. The main objective of this study was to determine resistant starch (RS) and total dietary fiber (TDF) content of the muffins using method (I) - AACC Method 32-07/AOAC Method 991.43 incorporating a pretreatment step with DMSO prior to enzyme incubation. RS content was also determined by 2 other methods: (II) - with pretreatment at 100 and 121 degree C prior to incubation with amyloglucosidase. (III) - samples were chewed by human subjects before incubation with pancreatin and amyloglucosidase. For method (I), on as eaten basis, TDF content ranged from 2.81 to 9.64 g/100 g for samples without DMSO pretreatment, 1.66 to 4.06 g/100 g with DMSO pretreatment. RS content ranged from 0.30 (Method I) to 11.18 g/100 g (Method II). Method II and III had the best correlation for all muffins tested (r2 = 0.97).