Sunday, 19 June 2005
3

This presentation is part of: Crops Posters/Reception

Texture Analysis of Food Grade Soybean Seeds.

Joyce Berger, Bo Zhang, and Pengyin Chen. 115 Plant Sci. Bldg. Dept of CSES, Univ. of Arkansas, Fayetteville, AR 72701

Natto soybeans are very small-seeded, uniform lines that are cooked and fermented for the Asian food market. In determining soybean suitability for natto manufacturing, seed hardness testing must be conducted. Usually, a professional natto taster performs this subjective test on a finished natto line. However, because hardness testing is time consuming and labor intensive, there must be a more objective, reproducible, and faster method for testing seed texture. The objectives of this study were 1) to compare the precision and efficacy of different seed hardness testing methods; and 2) to determine the optimal amount of cooked seeds required to quantify hardness. Five food grade soybean varieties (V97-6490, MFL-552, Hutcheson, MFS-591, and Camp) varying in seed size were analyzed with the one-bite method using a TMS Texture System (TMS-2000) equipped with a multiple blade shear cell and a TA-XT2i food texture analyzer equipped with a blade, a 2-mm probe, and a 75-mm cylinder. Dimensions of dry, soaked (16 hr), and cooked seeds (20 min at 121°C and 1.5 kg/cm2), water absorption capacity, swell ratio (weight and volume change), and hardness were quantified. The results showed that 30 g of cooked seeds had the lowest coefficient of variation for hardness (16%) with multiple blade shear cell as compared to 20 g, 40 g, and 50 g of cooked seeds. Five seeds simultaneously evaluated with the single blade and 10 seeds with the cylinder had the lowest coefficient of variation for hardness (11%). The single probe method is not recommended for soybean seed hardness testing because of the high coefficient of variation (25%). The peak value and area of the compression tests were positively correlated with swell ratio and soaked seed dimensions (79% and 69%).

See more of Crops Posters/Reception
See more of The ASA Southern Regional Branch (June 19-21, 2005)