Quality determination of Thai dried pickled fruits and vegetables.
Trongpanich K., Stonsaovapak S., Puminat W., Yunchalad M.
Author Affiliation: Institute of Food Research and Product Development, Kasetsart University, Chatuchak, Bangkok 10903, Thailand.
: 363-371
Abstract : Five varieties of Thai commercial dried and semi-dried pickled fruits and vegetables collected from local markets were examined for chemical and microbiological characteristics. Each product variety was sampled from 5 products. The sampling was done in triplication, for a total of 75 samples. The products were salted shredded green mango, salted shredded green papaya, sweeten shredded radish pickle, salted whole radish pickle, and whole peach pickle. The samples were analysed for pH, acidity (as lactic acid), aw, moisture, benzoic acid, sorbic acid, saccharin, NaCl and SO2. All samples were acidic with a pH value not more than 4.60, except for one sample of salted radish pickle pH 4.67. The mango and papaya pickles had aw of 0.85, while most of the radish and peach pickles had aw of >0.85. Most samples had saccharin, except for the salted whole radish and some samples of papaya, sweeten radish, and peach. Benzoic acid was found in most samples, while there were small amounts of sorbic acid and SO2 in some samples. The amounts of benzoic acid found in some samples were a little bit higher than 0.1%, especially in the radish pickles and peach pickle. This might be due to their high moisture content and high aw. Based on microbiological analysis, every sample, except radish pickles, contained TVC, yeast, mould, Clostridium perfringens, Staphylococcus aureus, and Bacillus cereus at 10 cfu/g, and coliform and E. coli at 3 MPN/g. Salmonella spp. was not found in 25 g sample. The microbiological quality of radish pickle samples, except for one sample of one brand, passed the Thai commodity product standard for flavoured radish pickle set by Thai Industrial Standards Institute. To decrease the amount of preservatives being used in the products that contain low microbial inhibiting factors, the producers should keep the products, after processing, at a low temperature (4°C).