61A-48 |
Quality traits of aromatic jasmine rice: Physicochemical characterization |
S. SUWANSRI, Dept. of Agro-Industry, Naresuan Univ., Phitsanuloke, 65000, Thailand and J. F. Meullenet, Dept. of Food Science, Univ. of Arkansas, 2650 N. Young Ave., Fayetteville, AR 72704. Jasmine rice grown in the United States has been found to be less acceptable by Asian consumers than imported products. Consumers have pointed weaknesses including color and texture of domestic products. Physicochemical data was though to be needed to assess differences between imported and domestic Jasmine rice. The objectives of this study were to (1) investigate physicochemical properties of domestic and imported milled Jasmine rice and (2) identify possible parameters indicative of Jasmine rice quality. Fifteen domestic and imported milled Jasmine rice products were characterized from physical tests (i.e., appearance, gel consistency, cooking test, and grain dimensions), instrumental texture (hardness and stickiness), and chemical (moisture, surface fat, protein, and amylose), pasting and thermal properties. Principal component analysis (PCA) was used to visualize the relationship among these properties. Results indicated that some factors (amylose content, hardness and stickiness ratio, surface fat, protein, and pasting properties) were key determinants of the texture and appearance quality of Jasmine rice. Most imported samples were low in amylose content and in hardness to stickiness ratio. Some of the domestic products were high amylose, medium gel-type, resulting in a harder texture of cooked rice. Surface fat and protein contents determined the appearance and thermal properties of Jasmine rice. High levels of surface fat and proteins resulted in a darker color and higher gelatinization temperatures, domestic samples being highest for both characteristics. The documentations of Jasmine rice physicochemical characteristics have illustrated the differences between domestic and imported products and pointed out the weaknesses of domestic Jasmine rice currently grown in the United States. The maps developed from this study could be used as quality evaluation tools for rice producers, importers, or breeders.
Session 61A, Carbohydrate
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