拐枣醋半固态-液态发酵工艺研究

Fermentation of Fruit Vinegar from Hovenia acerba

拐枣营养丰富,特别是含糖量很高,是一种极好的发酵食品原料。以拐枣为原料,通过加水打浆、酒精发酵、醋酸发酵等工序酿造果醋,对"两步法"酿造拐枣醋的加工方法进行研究,确定了拐枣醋加工合理的原料预处理方法、适宜的发酵方式和工艺参数。拐枣原料加水1.5倍打浆,直接进入发酵工序;酒精发酵采用带皮渣半固态发酵方式,接种0.1%的果酒酵母,发酵温度16℃左右,发酵时间80 h,发酵液酒精度为8.13%。醋酸发酵采用液态深层-分割留种发酵法,使用自制自吸式液态深层果醋发酵罐,接种10%活化的醋酸菌菌种,发酵温度34℃,第一轮发酵72 h,总酸度可达5.42%;分割留种发酵采用相同的发酵条件,仅需30 h即可完成醋酸发酵。实验确定的拐枣醋加工方法和工艺参数可以直接用于拐枣醋的加工生产。

Hovenia acerba is a nutritional food material for fermentation due to its high sugar content. Fruit vinegar was produced from the peduncles by pulping with water, alcoholic fermentation and acetic fermentation. The applicable ＂two-step＂ fermentation method and technological parameters were investigated. Skin-on fermentation was carried out in the alcoholic fermentation stage with technological parameters as addition of water to 1.5 times, inoculation with 0.1% Angel fruit wine yeast, fermentation at 16 ℃ for 80 h. The alcohol concentration of wine reached 8.13%（m/V）. Semicontinuous submerged fermentation was conducted in the acetic fermentation stage with a 5 L laboratory-scale fermenter for fruit vinegar production. The technological parameters of the acetic fermentation were as follows： inoculum size of acetic acid bacteria 10%, and fermentation temperature 34 ℃. It took 72 h to finish the first cycle of acetification with the titratable acidity of 5.42%（m/V）, and 30 h to finish the second cycle. The optimized processing method and technological parameters could be applied directly in the industrialized production of Hovenia acerba vinegar.