ราและอะฟลาทอกซินในน้ำพริกแกงและเครื่องเทศที่เป็นองค์ประกอบ / อดิพล ดิลกพิมล = Molds and aflatoxin in curry pastes and their spices / Adiphol Dilokpimol
To determine the amount and kind of molds in curry pastes and their spices, including the determination of the amount of benzoate sorbate and aflatoxin in curry pastes and to study of the change of curry pastes during storage at room temperature. Four kinds of curry pastes i.e. red curry paste, green curry paste, sour curry paste, and Thai-Indian curry paste were selected and each one comprised of 30 samples collected in 3 seasons. Ten kinds of main spices i.e. fresh cayenne pepper, green chili spur pepper, shallot, garlic, galangal, lemongrass, kaffir lime (skin), coriander (root), and lesser ginger and dried chili spur pepper were evaluated and each one comprised of 18 samples collected in 3 seasons. The samples were taken from wholesale market in Bangkok metropolis and vicinity. According to the amount and kind of molds in spices, garlic had the highest mold contamination (4.92+-0.39 logCFU/g), whereas, galangal had the least (0.08+-0.20 logCFU/g). The contaminated molds in spices were Aspergillus niger,Penicillium citrinum, P. corylophilum, Cladosporium spp., A. aculeatus, and A. flavus, respectively. For the curry pastes, sour curry paste had the highest amount of mold contamination (2.40+-1.07 logCFU/g), then, red curry paste (1.44+-1.12 logCFU/g), Thai-Indian curry paste (0.78+-0.79 logCFU/g) and green curry paste (0.68+-1.09 logCFU/g), respectively. A. niger, Monascus spp. and Paecilomyces spp. were the most contaminated molds in curry pastes. For the determination of benzoate and sorbate, 40% of the curry paste had benzoate more than 1,000 ppm, whereas, 20 % of the curry paste had no benzoate. Moreover, sorbate was not detected in all samples. On the other hand, the use of sorbate and benzoate were not effective to inhibit the growth of molds because the pH range was not appropriate for these preservatives. According to the determination of aflatoxin, dried chili, cayenne pepper, green chili spur pepper, lemongrass, and lesser ginger were contaminated by aflatoxin less than 5 ppb while galangal and kaffir lime (skin) were contaminated less than 20 ppb. No aflatoxin was detected in shallot, garlic, and coriander (root). For the curry pastes, all samples were contaminated by aflatoxin less than 20 ppb. According to the sensory evaluation, the shelf-life of sour curry paste, green curry paste, red curry paste and Thai-Indian curry paste were 2, 3, 5, and 13 days, respectively. Furthermore, there is no change of mold counts during the storage time tested and the use of 500 ppm sodium benzoate and potassium sorbate can not extend the storage life of those tested curry paste (p>0.05).
