18A-22 |
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J. M. KING and S. Y. Tan. Dept. of Food Science, LSU AgCenter, 111 Food Science Bldg., Louisiana State University, Baton Rouge, LA 70803-4200 Carbohydrates have been associated with increased health risks, such as type 2 diabetes and obesity. Inclusion of RS in the diet may be the missing link to reducing obesity. RS is a functional food ingredient that is resistant to digestion and provides similar health benefits as fiber. There are no commercial resistant rice starches currently available and there have been no previously published studies on developing resistant rice starch. The objectives of this study were to determine which combination of enzymes produced the highest level of RS in rice starch and to examine the effects of gelatinization type and incubation period on RS yield. Aqueous solutions (7%) of rice starch were treated with enzymes with or without prior gelatinization or refrigerated storage. Pullulanase or α-amylase was used alone or in combination at optimum temperatures to hydrolyze the starches. Enzymes treatments proceeded for 0, 4, or 16 hours with shaking. Resistant starch was assayed as dietary fiber and quantified using a glucose oxidase assay kit by the McCleary method. Non-gelled, non stored samples had higher resistant starch contents than gelled samples with and without storage. Most gelled samples had levels of RS below the original starting material. The starting rice starch material had a RS content of 5%. Pullulanase gave higher RS levels than either α-amylase alone or the combination of enzymes. Pullulanase alone at 4 hours of treatment without gelatinization produced the highest amount of RS overall, 60%, among the three enzyme combinations, followed by α-amylase-pullulanase combination and then α-amylase alone. This research resulted in the development of a resistant rice starch from a non-hypoallergenic source that can be used in foods a healthy ingredient.
Session 18A, Carbohydrate: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |