Isolation of thermotolerant acidophlic bacteria (TAB) from fruit juices

To investigate the contamination of commercial fruit juice beverages by thermostable acidophilic bacteria (TAB) in Japan, 208 samples of fruit juice beverages produced in Japan and 162 samples of imported beverages (total of 370 samples) purchased in 2004 were investigated according to the 'Standard Test Method for Thermostable Acidophilic Bacteria' proposed by the Japan Fruit Beverage Association. TAB was isolated from 9 of the beverages made in Japan (4.3%) and 19 of the imported beverages (11.7%), showing about a 3-fold higher isolation rate. The origins of the imported beverages from which TAB was isolated were widely distributed: Thailand, Indonesia, Korea, France, Germany, Spain, Australia, America, Mexico, and South Africa. Three of the 9 domestic products from which TAB was isolated were mixed juice. As the 2nd most frequently contaminated beverage, 2 orange juice products were contaminated, and 1 sample each of apple, grape, grapefruit, and pineapple juices were also contaminated. Regarding the imported beverages, 5 of the 19 samples from which TAB was isolated were mixed juice, as in the Japan-made products. The 2nd most frequently contaminated beverages were 3 orange juice products. TAB was also isolated from 2 samples each of grape, mango, and pineapple juices, and 1 sample each of apple, cherry, peach, and prune juices. TAB was isolated from various fruit juice beverages regardless of whether they were domestic products or imports. All of the 9 Japan-made beverages contaminated with TAB were concentrated products, and the bacteria were not detected in any of the pure direct products. The same tendency was noted in the imported beverages. Ten of the 19 samples (52.6%) contaminated with TAB were concentrated, and only 1 straight sample (5.3%) was contaminated. Seven of the 9 contaminated domestic products (77.8%) were paper-packed, and 1 sample each was packed in a can or PET bottle. As for the imported beverages, 8 beverages (42.1%) were most frequently paper-packed, as in the Japan-made products, and 6 (31.6%), 3 (15.8%), and 2 (10.5%) beverages were packed in a bottle, PET bottle, and can, respectively.