Time temperature indicators (TTIs) are devices used for recording thermal history and indicating the remaining shelf life of perishable products throughout their storage, distribution and consumption. This is achieved by the irreversible change of colour resulting from the cumulative effects of time and temperature. When applied in intelligent packaging, TTI can provide visual information that is easily accessible, and thus, consumers can judge from the visual information whether the food has deteriorated, which helps to assure the quality and safety of food. TTI can be classified into several different groups including chemical TTI, physical TTI, biological TTI, and other new types of TTI based upon different principles of colour change. Although these kinds of TTI can basically provide effective information about food quality, there are still a number of problems with them in the food supply chain, such as migration of toxic substances, the inaccuracy of temperature monitoring and the high cost in the area of commercial application. However, there are also some scientific methods to solve the aforementioned problems of TTI. In this paper, the latest research of TTI is summarized, its status and its main problems are elaborated and the prospect of its development is envisaged, aiming to provide reference and support for researchers in this realm.

Forty-three samples of kurut, a kind of traditional naturally-fermented yak milk, were collected in Qinghai, China. One hundred and forty-eight lactic acid bacterial (LAB) strains were isolated and identifi ed from the kurut samples according to phenotypic characterization and 16S rRNA gene sequence analysis. Among them, 52 isolates belonged to the Lactobacillus strains. Ninety-six isolates were resolved to coccoid LAB. The results showed that these isolates belonged to fi ve genera and thirteen different species and subspecies. Moreover, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus were the predominant population in these samples. This paper systematically studied the composition of LAB in kurut, which may provide raw data for further study involving probiotics strain selection and starter culture design for industrialization production of traditional fermented milk in the future. lactic acid bacteria (LAB). The presence of fermentative LAB is crucial to the intrinsic properties of fermented dairy products (Ehrmann et al., 2002;Tamine and Robinson, 1988). LAB have a long history of safe use, especially in the dairy industry. They play a major role in the production of fermented food, such as the key fl avor, texture and preservative qualities (Ahmad and Irene, 2007;Atrih et al., 2001;Messens and Vuyst, 2002). Recently, some of them have been completely sequenced (Altermann et al., 2005;Guchte et al., 2006;Pridmore et al., 2004). Therefore, comparative genomic analysis can help us to understand the genetic and biological diversity in LAB (Makarova and Koonin, 2007;Makarova et al., 2006;Morita et al., 2008). Key Words-identifiAs yet, information on microbiological composition of kurut is scant. Thus, it is necessary to select LAB strains with benefi cial function and stabile fermentation properties from the traditional fermented milk products, and then use them to design the starter cultures for commercial production. Based on this point, this study was undertaken to enumerate, isolate, identify and characterize the dominant microorganisms from kurut samples obtained from Qinghai, using the conventional method and 16S rRNA sequence analyses. Materials and MethodsSample collection. A total of 43 samples of kurut were collected from scattered households in Qinghai Province of China with temperature ranging from 10.8 C to 39.3 C. At each location, approximately 500 ml kurut were taken aseptically into sterile glass bottles after through mixing in the bulk kurut container. The pH values of these samples were determined at the sampling site using a calibrated portable pH-meter (pH100, Extech, USA). The kurut was collected within 15 min at ambient temperatures, and kept on ice during a 2 h transport. The operation for collection of all kurut samples was completed within 48 h. The microbiological analysis was carried out immediately after the samples arrived at the laboratory.Reference Enumeration of microorganisms. The 10 1 dilution was made by diluting 1 ml of kurut within 9 ml of physiol...

Aims:  To isolate a bacterium that produces high yield of melanin and to examine the effect of this bacterial pigment on the efficacy of a bioinsecticide. Methods and Results:  A novel melanin‐producing bacterium, designated as strain WS, was isolated from the East Lake, Wuhan, China. Taxonomic studies of this strain indicate that it belongs to Aeromonas media. Physicochemical analysis of the pigment produced by strain WS (melanin WS) suggests that it is the authentic 3,4‐dihydroxyphenylalanine (DOPA)‐melanin. This melanin and that produced by Pseudomonas maltophilia P28 (melanin P28) share many biophysical properties, but the yield of the melanin WS is significantly higher than that of the melanin P28. In addition, the melanin WS appears to be more effective in the protection of a bioinsecticide against ultraviolet (UV) or solar radiation. At the concentration of 10 ppm, the melanin P28 exhibited no photoprotective effect on the bioinsecticide against UV radiation; in contrast, 5 ppm of melanin WS displayed an obvious protective effect. Similarly, the melanin WS displayed more protective effect on the bioinsecticide against solar radiation than the melanin P28 did over a 4‐day period, with the effect being more dramatic for the last 2 days. Conclusions:  We have isolated a novel bacterial strain of A. media that produces high levels of melanin. The melanin produced by this strain offers effective photoprotection of a commercial bioinsecticide BTI against UV and solar radiation. Significance and Impact of the Study:  Our study suggests that the melanin produced by our newly isolated A. media strain has the potential to be used as a general photoprotective agent for bioinsecticides.

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