comparative study of submicron- and micron-sized rice particles: enzymatic hydrolysis in vitro and food efficiency ratio in vivo

• Published in: International journal of food science & technology Vol. 46; no. 2; pp. 372 - 378
• Main Authors: Lee, Kyung-Ae, Ryu, Min-Ju, Kim, Moo-Sung, Kang, Wie-Soo, Ko, Sanghoon, Shin, Malshick, Chung, Ha-Sook
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.02.2011; Wiley-Blackwell
• Subjects: Absorption; Biocompatibility; Biological and medical sciences; Biomedical materials; Cereal and baking product industries; food efficiency ratio; Food industries; Foods; Fundamental and applied biological sciences. Psychology; Hydrolysis; In vivo testing; In vivo tests; micron; particle size; Rice; rice powder; submicron; Surgical implants; Particle size; submicron; In vitro; Powder; Hydrolysis; Particle; In vivo; Absorption; food efficiency ratio; Efficiency; Cereal; Ratio; micron; rice powder; Food; Rice; Enzymatic reaction
• ISSN: 0950-5423; 1365-2621
• DOI: 10.1111/j.1365-2621.2010.02502.x

Hydrolysis and absorption properties of submicron- (below 1 μm) and micron-sized (over 100 μm) powders of raw rice, heat-gelatinized rice, fermented rice and wheat were investigated in vitro and in vivo. Nutrient content such as protein, carbohydrate or vitamin C in the samples was not different significantly between submicron- and micron-sized powders, but it showed difference according to processed type of the powders. Submicron-sized powders were hydrolyzed more easily than micron-sized powders by α-amylases such as industrial, human salivary and porcine pancreatic α-amylase but not by α-glucosidase in all the tested samples. Patterns of blood glucose change were investigated in rats. The highest glucose levels were obtained at 30 min after oral administration in both submicron-and micron-sized powders, but the levels were decreased drastically in groups administered submicron-sized powders, while they were slow and gradual in groups administered micron-sized powders. On the contrary, the body weight gained and food efficiency ratios showed a tendency to be decreased slightly in mice fed with submicron-sized rice powders compared to those with micron-sized rice powder.