乳酸菌发酵辅助酶法制备香蕉皮可溶性膳食纤维及功能性质分析

Preparation and Functional Property Analysis of Banana Peel Soluble Dietary Fiber via Lactobacillus Fermentation-assisted Enzymatic Method

摘要:

为有效利用废弃香蕉皮资源并提高产品附加值，该研究采用乳酸菌发酵辅助酶法制备香蕉皮膳食纤维（BP-SDF）并优化其工艺条件，进一步分析了最佳工艺下香蕉皮粉（BP）、BP-SDF及香蕉皮不溶性膳食纤维（BP-IDF）的理化及功能性质。结果表明：最佳发酵工艺为鼠李糖乳杆菌接种量为3.0 wt.%、发酵温度38 ℃、发酵时间18 h，BP-SDF得率为32.18%，鼠李糖乳杆菌发酵辅助酶法对BP-SDF提取率较传统酶法提高了2.0倍。与酶法提取香蕉皮膳食纤维相比，BP-SDF的溶解性、持水力及吸水膨胀力均极显著提升，溶解性增强7.1倍，持油力变化不明显。BP-SDF对DPPH•、O2-•、ABTS+•、OH•具有一定清除能力，表现出较好的抗氧化活性。BP-SDF和BP-IDF对胆固醇、亚硝酸盐吸附能力均显著提升，且两者在胃环境（pH值2）中吸附能力显著高于肠道环境（pH值7），此外BP-SDF还表现出良好的降血糖活性。因此，乳酸菌发酵辅助酶法是一种可行的香蕉皮皮膳食纤维制备方法，可为香蕉皮粉膳食纤维功能研究提供理论依据。

Abstract:

To effectively utilize waste banana peel resources and increase the added value of products, the Lactobacillus fermentation-assisted enzymatic method was used to extract banana peel soluble dietary fibers (BP-SDF), and the process conditions were optimized. Further analysis was performed to determine the physicochemical properties and functional characteristics of banana peel powder (BP), BP-SDF, and banana peel insoluble dietary fiber (BP-IDF) obtained under optimized conditions. The results showed that the optimal fermentation process was as follows: inoculation with 3.0 wt.% Lactobacillus rhamnosus, fermentation temperature of 38 ℃, and fermentation time of 18 h. Under these conditions, the yield of BP-SDF was 32.18%; its extraction rate was 2.0-fold higher than that obtained using the traditional enzymatic method. Compared with the enzymatic extraction of dietary fibers from banana peels, BP-SDF showed significant improvements in solubility, water-holding capacity, water absorption, and swelling capacity, with solubility increasing by 7.1-fold. The oil-holding capacity showed no significant changes. In addition, BP-SDF scavenged DPPH•, O2-•, ABTS+•, and OH• free radicals, demonstrating good antioxidant activity. The adsorption capacity of BP-SDF and BP-IDF for cholesterol and nitrite was significantly improved, whereas the adsorption capacity of BP-SDF in the gastric environment (pH 2) was significantly higher than that in intestinal environment (pH 7). Furthermore, BP-SDF showed better glucose-lowering activity. Therefore, the Lactobacillus fermentation-assisted enzymatic method is a feasible approach for preparing BP-SDF. This study provides a theoretical basis for the high-value utilization of BP-SDFs.