Musyoka Joyce Ndunge, Abong' George Ooko, Mbogo Daniel Mahuga, Fuchs Richard, Low Jan, Heck Simon, Muzhingi Tawanda
Department of Food Science, Nutrition and Technology, University of Nairobi, P.O. Box 29053-00625, Kangemi, Kenya.
International Potato Center (CIP), Sub-Saharan Africa (SSA) Regional Office, Old Naivasha Road, P.O. Box 25171-00603, Nairobi, Kenya.
Int J Food Sci. 2018 Jun 7;2018:8410747. doi: 10.1155/2018/8410747. eCollection 2018.
Orange Fleshed Sweet Potato (OFSP) puree, a versatile food ingredient, is highly perishable limiting its use in resource constrained environments. It is therefore important to develop shelf-stable puree. A challenge test study was carried out to determine the effect of combinations of chemical preservatives and acidification on microbial growth in stored puree. Puree was prepared and treated as follows: control (); 0.05% potassium sorbate+0.05% sodium benzoate+1% citric acid (); 0.1% potassium sorbate+0.1% sodium benzoate+1% citric acid (); 0.2% potassium sorbate+0.2% sodium benzoate+1% citric acid (); 1% citric acid (). Samples were inoculated with and at levels of 5.2 x 10 cfu/100g and 1.5 x 10 cfu/100g, respectively, before being evaluated during storage for 10 weeks at prevailing ambient temperature (15-25°C) and refrigeration temperature (4°C). Total aerobic counts, yeasts, and molds were also evaluated. and counts declined significantly (p<0.05) by 4 log cycles in all puree treatments except for control and puree with only citric acid. Total viable count, yeasts, and molds were completely inhibited except for puree with only citric acid. Combination of chemical preservatives and acidification is effective in inhibiting pathogens and spoilage microorganisms in sweet potato puree.
橙色肉甜薯（OFSP）泥是一种用途广泛的食品原料，但极易腐坏，这限制了它在资源有限环境中的使用。因此，开发货架期稳定的甜薯泥很重要。开展了一项挑战测试研究，以确定化学防腐剂和酸化处理的组合对储存甜薯泥中微生物生长的影响。甜薯泥的制备和处理如下：对照组（）；0.05%山梨酸钾+0.05%苯甲酸钠+1%柠檬酸（）；0.1%山梨酸钾+0.1%苯甲酸钠+1%柠檬酸（）；0.2%山梨酸钾+0.2%苯甲酸钠+1%柠檬酸（）；1%柠檬酸（）。在分别以5.2×10 cfu/100g和1.5×10 cfu/100g的水平接种 和 后，将样品在当时的环境温度（15 - 25°C）和冷藏温度（4°C）下储存10周期间进行评估。还评估了需氧菌总数、酵母菌和霉菌。除了对照组和仅含柠檬酸的甜薯泥外，在所有甜薯泥处理中， 和 的数量均显著下降（p<0.05）4个对数周期。除了仅含柠檬酸的甜薯泥外，总活菌数、酵母菌和霉菌均被完全抑制。化学防腐剂和酸化处理的组合可有效抑制甜薯泥中的病原体和腐败微生物。
