乳酸菌发酵对猕猴桃果渣可溶性膳食纤维制备和理化性质的影响

Influence of Lactic Acid Bacteria Fermentation on the Preparation and Physicochemical Properties of Soluble Dietary Fiber from Kiwifruit Pomace

摘要:

为了提高乳酸菌发酵制备果蔬加工副产物可溶性膳食纤维（Soluble Dietary Fiber, SDF）的得率，该研究以“徐香”猕猴桃果渣为原料采取单因素试验和正交试验优化其制备工艺，并与酸提法及酶提法制备的样品进行了比较。结果表明，发酵法制备SDF的最佳工艺条件为：料液比1:20（g/mL）、发酵时间48 h、发酵温度35 ℃、起始pH值3.0、接种量10%（发酵体系体积分数），在该条件下猕猴桃果渣SDF的得率为17.83%，高于酸提法（14.93%）和酶提法（15.69%）。理化性质分析表明，发酵法制备的SDF持水力（11.01 g/g）、溶胀力（8.66 mL/g）、溶解率（90.12%）、结合水能力（15.46 g/g）及亚硝酸盐吸附力889.61 μg/g（pH值2.0），282.80 μg/g（pH值7.0），综合表现优于酸提法和酶提法制备的样品。上述研究结果表明，猕猴桃果渣是优质的可溶性膳食纤维来源，研究为猕猴桃加工副产物的高值化利用提供了理论依据。

Abstract:

In order to improve the yield of soluble dietary fiber (SDF) prepared from fruit and vegetable pomace by lactic acid bacteria fermentation, the "Xuxiang" kiwifruit pomace was used as the raw material in this research. Single-factor experiments and orthogonal experiments were conducted to optimize the preparation process, and the samples prepared by fermentation were compared with those prepared by the acid extraction and enzymatic assisted extraction. The results showed that the optimal process conditions for preparing SDF by fermentation were: material to liquid ratio, 1:20 (g/mL); fermentation time, 48 hours; fermentation temperature, 35 ℃ ; initial pH, 3.0; inoculum volume, 10% (volume fraction of fermentation system). Under these conditions, the yield of SDF from kiwifruit pomace was 17.83%, which was higher than those of the acid method (14.93%) and enzymatic method (15.69%). The analysis of physicochemical properties revealed that the SDF prepared by fermentation had a water holding capacity of 11.01 g/g, swelling capacity of 8.66 mL/g, solubility of 90.12%, water-binding capacity of 15.46 g/g, and nitrite adsorption capacities of 889.61 μg/g at pH 2.0 and 282.80 μg/g at pH 7.0, showing superior properties of this SDF compared to those of the SDF samples obtained by the acid and enzymatic methods. The above research results indicate that kiwifruit pomace is a high-quality source of soluble dietary fiber, and the research provides a theoretical basis for the high-value utilization of kiwifruit processing by-products.