67C-5 |
|
S. P. HONG, Animal Resources, Korea Food Research Institute, San 46-1 Baekhyun Bundangku, Seongnam Kyonggido, IA, South Korea, D. U. Ahn, Dept. of Animal Science, Iowa State Univ., 2276 Kildee Hall, Ames, IA 50010-3150, and E. J. Lee, Animal Science Department, Iowa State University, 2373 Kildee Hall, Ames, IA 50011. Kimchi is a traditional korean food product prepared with lactic acid fermentation of Chinese cabbage and seasoning mixture composed of red pepper, garlic, green onion, radish, etc. Kimchi powder can also be added to other food products such as various sauces or dressing to introduce the characteristic kimchi flavor. However, the microorganisms in kimchi have been the main problems in applying kimchi as a flavor enhancer, and irradiation can be an efficient tool to eliminate microorganisms in kimchi powder. The objective of this study was to investigate the effect of irradiation on the quality characteristics of premature (pH 5.0) and mature kimchi (pH 4.2) powders. Kimchi powders were irradiated at 0, 5, 10 or 30 kGy using a Linear Accelerator. CIE color values were determined by LabScan spectrophotometer, volatile profiles by a dynamic headspace-GC/MS method, and odor and taste characteristics by a 10-member trained sensory panel, and microbial count using PCA, PDA, and MRS agar. Irradiation significantly decreased a* (redness) and b* (yellowness) values of kimchi powders, and the increased a and b values were irradiation dose dependent while L* (lightness) value was not influenced by irradiation. Volatile profiles indicated that 2-butanone, acetic acid, and butanal were newly produced in both kimchi powders by irradiation at 30kGy. Dipropyl disulfide were detected only in matured kimchi. However, no significant off-odor or off-taste were developed in both kimchi powders by irradiation, but the degree of hot taste decreased and sweet taste increased with the increase of irradiation dose. The number of microorganisms in kimchi powders decreased in proportion to irradiation dose and no microrganisms were detected with 30 kGy irradiation. It was concluded that irradiation could control microorganisms without significant changes in the quality of kimchi powders. Therefore, irradiated kimchi powders can be used as a seasoning material for other sauces or dressings to enhance kimchi flavor.
Session 67C, Food Chemistry: Food analysis, irradiation and toxicology
|