39C-8

K. M. KIM¹, J. G. KIM¹, Y. I. CHANG², and W. J. KIM³. (1) Department of home economics, Sejong University, 98 Kunja-dong, Kwangjin-ku, Seoul, 143-747, South Korea, (2) Department of food science and technology, Chungnam National University, 220 Gung-dong, Yusung-ku, Taejon, 305-764, South Korea, (3) Department of food science, Sejong University, 98 Kunja-dong, Kwangjin-ku, Seoul, 143-747, South Korea

(1) Justification: The textural properties and yellowness of steamed whole egg were considered as important factors to evaluate its quality. (2) Objective: This study was conducted to compare the textural characteristics, stress at failure(SF), strain at failure(NF) and hardness(HD), and color of steamed whole egg(SWE) as affected by pH and water content and find out their correlation among all quality parameters (3) Method: Clean fresh shell eggs were first washed, broke, separated into whole egg and egg shell, and then filtered to remove vitelline membrane and chalazae, froze and thawed in water bath 30 degree C for 30 min when used. The steamed whole egg was prepared by stirring, degassing, heating at 100 degree C for 7 min., cooling at 22 degree C for 90 min. and measuring textural and color properties. (4) Results: The textural characteristics of the SWE significantly changed (p<0.05) with pH. Stress at failure and HD of the SWE showed the highest value at pH 6.5 but both characteristics showed the lower value as pH increased. Hunter L and b value decreased significantly (p<0.05) as pH increased. Hardness of SWE significantly decreased (p<0.05) with increasing water content. Stress and strain at failure of SWE were not significantly different between 1.0 and 1.5% of water content. Only Hunter L value of SWE significantly decreased (p<0.05) as water content increased from 0 to 1.5%. There were highly correlated (p<0.001) between pH and other parameters except SF. Hardness of SWE was highly correlated with all parameters except Hunter a value for both the change of pH and water content during the cooking of SWE. (5) Significance: Yellowness, one of the important factors, of the steamed whole egg was not much changed with water content. Hardness of the SWE could be used as an good indicator to evaluate its quality.