Microbiological quality of ready-to-eat spice-stewed food products and the effects of storage temperatures on the bacterial counts of these products

• Main Authors: Mei-Chu Huang, 黃美珠
• Other Authors: Guo-Jane Tsai
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/66158196778137009261

碩士 === 國立臺灣海洋大學 === 食品科學系 === 92 === The objective of this study was to investigate the microbiological quality of various types of ready-to-eat (RTE) spice-stewed food products A total of 357 samples of RTE spice-stewed food products, including 44 giblets, 98 bean curds, 85 kelps, 77 eggs and 53 chicken souse-vides, which were purchased in Aug. 2003- Feb. 2004 from snack bars, night-markets, supermarkets, and traditional-markets in Taipei, were examined. In total, there is 206 samples (57.7%) unqualified in total aerobic count that is over the limit of 105 CFU/g, especially the unqualified percentage for giblet, bean curd and kelp even reached to 60.20% ~ 62.35%. The unqualified sample number (percentage) in coliform content over 10 MPN/g is 245 (68.63%), with egg (72.73%) and bean curd (71.43%) being the highest. The unqualified sample number (percentage) in the content of Clostridium perfringens over 100 CFU/g is 36 (10.08%), with giblet (18.18%) being the highest. The detection rates for the presence of Escherichia coli, Staphylococcus aureus and vibrio parahaemolyticus were 16.25%, 15.69%, 2.25%, respectively. The tested samples showed large variation in the contents of the total aerobic counts and coliform count. The unqualified samples numbers in total aerobic count, coliform, E. coli and S. aureus were significantly higher for samples purchased from snack bars and night-markets than from supermarkets and traditional-markets. The samples from night-markets showed the highest unqualified percentage (21.01%) in the item of C. perfringens content. Both storage temperature and time significantly affected the total aerobic count of the spice-stewed food. Based on the result of the storage test of the self-made spice-stewed food, the shelf-life of the spice-stewed food at 35℃ was less than 12 h, and 24 h for 25℃ storage with exception of bean curd, which was 38 h for 25℃storage. The total aerobic counts was not detectable for samples stored at 4℃ for 4 days.