响应面法优化核桃乳发酵工艺

本研究以脱脂核桃粕为原料,在单因素实验的基础上应用响应面法对核桃乳发酵工艺进行优化。以接种量、植物乳杆菌与嗜酸乳杆菌配比、发酵时间、发酵温度为因素,以感官评价为指标,研究各因素及其交互作用对发酵核桃乳感官品质的影响。结果表明,最佳生产工艺条件为:植物乳杆菌与嗜酸乳杆菌比例为1:1,接种量8%,发酵温度41℃,发酵时间12.7 h。所得到的产品色泽均匀,核桃香味充足,酸甜适口,口感丝滑,后熟12 h的pH和总酸含量3.88、25.63 g/kg,活菌数7.78×108 cfu/mL,蛋白质含量1.05 g/100 g,氨基态氮含量68.6 mg/100 g,与未发酵的核桃乳相比,氨基酸总含量增加了0.1738%。

Optimization of Walnut Milk Fermentation Process by Response Surface Methodology

The defatted-walnut milk as the raw material was fermented in this experiment. Based on the single-factor experiments,the fermentation processing of walnut milk was optimized by the response surface method. The impacts of inoculation amount,ratio of strain,fermentation time and fermentation temperature on the sensory quality of fermented walnut milk were investigated. The result showed that the optimal fermentation processing conditions were as follows:Volume ratio of Lactobacillus plantarum to Lactobacillus acidophilus 1:1,8% of inoculation amount,41℃ fermentation temperature and 12.7 h fermentation time. In addition,the fermented product had the uniform color,strong walnut flavor,sweet,sour and smooth taste. After 12 h,the pH value and total acid were 3.88 and 25.63 g/kg,the number of viable bacteria was 7.78×108 cfu/mL,the protein contents was 1.05 g/100 g,the amino nitrogen contents was 68.6 mg/100 g,the total content of amino acids increased by 0.1738%.