Selvamuthukumaran M.,DFRL |
International Food Research Journal | Year: 2014
Antioxidant rich fruit yoghurt was developed utilizing seabuckthorn fruit syrup using yoghurt culture. The resultant product had higher content of fat, protein, carbohydrate and antioxidants (vitamin C, vitamin E, carotenoids, phenols, anthocyanins) when compared to a commercial yoghurt. The shelf stability studies of yoghurt were assessed at room temperature, 15°C and 4°C. The product stored at room temperature exhibited offflavor and acidic taste within a day of storage, while the product stored at 4°C and 15° C exhibited significant increase in acidity and syneresis during 9nth and 6th day of storage period respectively. The total solids, pH and viscosity significantly decreased on 18nth, 9nth and 6nt day of storage at 4°C and for 15°C it was on 9nth, 6th and 3rd day of storage respectively. No remarkable change was noted for fat, protein, carbohydrate and antioxidants during storage. The sensory quality of product drastically reduced after 18 days at 4°C and 9 days at 15°C. The count of both yoghurt cultures viz. Lactobacillus bulgaricus and Streptococcus thermophilus significantly decreased during the entire storage period. The yeast and mould count was absent in fresh samples, but were detected on 21st day at 4°C and 6th day at 15°C. Likewise, the coliform count was initially absent but was detected on 15th and 6th day when stored at 4 and 15°C temperature respectively. The product was found to be acceptable up to a period of 12 days at 4°C and 3 days at 15°C without posing any threat to the consumers.
Ramana M.V.,DFRL |
Balakrishna K.,DFRL |
Murali H.C.S.,DFRL |
Journal of the Science of Food and Agriculture | Year: 2011
The genus Fusarium comprises a diverse group of fungi including several species that produce mycotoxins in food commodities. In the present study, a multiplex PCR was standardised for the group-specific detection of fumonisin-producing and trichothecene-producing strains of Fusarium species. Primers for genus-level recognition of Fusarium spp. were designed from the internal transcribed spacer regions 1 and 2 of rDNA. Primers for group-specific detection were designed from the tri5 and tri6 genes involved in trichothecene biosynthesis and the fum1 and fum13 genes involved in fumonisin biosynthesis. RESULTS: Among the various genera and their strains tested, all the 85 confirmed Fusarium strains were positive for rDNA gene and the rest stayed negative. From among the Fusarium strains, 15 had amplification for trichothecene- and 20 for fumonisin-encoding genes. All PCR positive trichothecene chemotypes of Fusarium species tested were positive for chemical analysis but in the case of fumonisins, of the 20 PCR positive cultures, only 13 showed positive for chemical analysis by HPTLC. CONCLUSION: The assay described here provided a rapid and reliable detection of trichothecene- and fumonisin-producing Fusarium directly from natural food grains and the results were always comparable with a conventional HPTLC detection method. It can, therefore, be used by the food industry to monitor quality and safety. © 2011 Society of Chemical Industry.