著者
Yukie Hosotani Nobutaka Nakamura Hideki Kito Yasuhiro Inatsu
出版者
Japanese Society for Food Science and Technology
雑誌
Food Science and Technology Research (ISSN:13446606)
巻号頁・発行日
pp.FSTR-D-22-00209, (Released:2023-02-28)

In the present study, the effectiveness of sterilization of peracetic acid (PA) solution and sodium hypochlorite (SH) solution for several fungi (Penicillium sp., Cladosporium sp., and Fusarium sp.) attached on the cut surface of sweet potato (Ipomoea batatas) was evaluated. The mixture of each strain isolated from rotten sweet potatoes was inoculated on the cut surface of presterilized sweet potato blocks. Further, each inoculated cut potato was washed with water, 200 mg⁄L SH, a mixture of SH, and 100 mM acetic acid (SH+AA), or 20–80 mg⁄L PA for 5 minutes at room temperature. Comparing with the untreated ones (4.2–5.1 log CFU⁄mL), the 80 mg/L PA washing could reduce 2.2, 2.2, and 2.0 log CFU⁄mL of Penicillium, Fusarium, and Cladosporium species, respectively. The increasing concentration of PA resulted in an increase the fungicidal efficiency. The use of 80 mg⁄L PA solution was suggested to be more highly effective than the one of (pH controlled) SH solution to control the spoilage fungi on cut sweet potato.
著者
Chiraporn ANANCHAIPATTANA Yukie HOSOTANI Susumu KAWASAKI Sirikhae PONGSWAT Bari Md. LATIFUL Seiichiro ISOBE Yasuhiro INATSU
出版者
Japanese Society for Food Science and Technology
雑誌
Food Science and Technology Research (ISSN:13446606)
巻号頁・発行日
vol.18, no.6, pp.843-848, 2012 (Released:2013-01-11)
参考文献数
14
被引用文献数
4 18

Soybean curd (Tofu) is a popular food for many people, especially those with health concerns. The objective of this study, therefore, was to evaluate the contamination rate and types of foodborne pathogens and food spoilage bacteria in packaged and unpackaged tofu sold in Thai markets. A total of 133 tofu samples (59 packaged tofu samples and 74 unpackaged tofu samples) were collected from open markets and supermarkets in Thailand. The predominantly identified Gram-negative bacteria were coliforms (67% in tested samples), Pseudomonas spp. (56%) and Escherichia coli (28%) and the predominantly identified Gram-positive bacteria were Enterococcus spp. (77%), lactic acid bacteria (68%), Bacillus cereus (41%) and Staphylococcus spp. (26%). No Listeria spp. were found in any of the tofu samples. The contamination rates of E. coli, Salmonella spp. and Enterococcus spp. in unpackaged tofu were significantly higher than those in packaged tofu (P < 0.05). Three kinds of Gram-negative pathogenic bacteria, Cronobacter sakazakii, Salmonella spp. and Yersinia enterocolitica (serotype 0:5), were found only in unpackaged tofu samples. Of 54 B. cereus isolates, four isolates from three unpackaged tofu samples and one packaged tofu sample were found to produce diarrheal enterotoxin. The most common Enterococcus spp. isolates were Enterococcus faecium and Enterococcus faecalis. These results suggested that the improvement of hygienic practices might be required for reducing the risk of food poisoning and food spoilage of tofu in Thailand.