梨渣可溶性膳食纤维提取工艺优化及功能特性分析

Extraction Process Optimization and Analysis of Functional Characteristics of Soluble Dietary Fibers of Pear Pomace

摘要:

采用纤维素酶酶解制备梨渣可溶性膳食纤维（SDF），以梨渣SDF得率为评价指标，通过单因素和响应面优化酶解制备SDF的最佳工艺条件，并分析可溶性膳食纤维的理化性质和功能特性。结果表明，SDF最佳提取工艺为酶底质量比1.1%、时间5.2 h、料液比1:21、温度37 ℃、pH值4.5，在此条件下进行的验证试验SDF得率为6.29%，与理论值6.23%较相符。与原梨渣相比，SDF的持水性和膨胀性均得到提高，且SDF对DPPH（IC50=0.494 mg/mL）和ABTS+（IC50=0.429 mg/mL）自由基具有一定的清除能力，表现出较好的抗氧化活性。SDF在肠道中表现出更好的胆固醇吸附能力（4.81 mg/g），但在胃环境（84.68%）中对NO2- 的吸附能力显著高于肠道环境（16.21%）。梨渣可溶性膳食纤维具有较好的理化功能特性，该研究为梨渣的高值化利用提供了理论依据。

Abstract:

The soluble dietary fibers (SDF) of pear pomace were prepared by enzymatic hydrolysis using cellulases, and the SDF yield was taken as the evaluation index to optimize the process conditions for the preparation of SDF by enzymatic hydrolysis through single factor experiments and response surface methodology. The physicochemical properties and functional characteristics of the pear pomace SDF were analyzed. The results showed the SDF extraction process to be optimized under the following conditions: an enzyme/substrate mass ratio of 1.1%, reaction time of 5.2 h, material-to-liquid ratio of 1:21, reaction temperature of 37 ℃, and a pH value of 4.5. The resulting experimental SDF yield equaled 6.29%, which was consistent with the theoretical value of 6.23%. The SDF showed improved water holding and swelling capacity compared to the original pear pomace. In addition, SDF could scavenge DPPH (IC50=0.494 mg/mL) and ABTS+ (IC50=0.429 mg/mL) free radicals, demonstrating good antioxidant activity. SDF showed better cholesterol adsorption performance in the intestine (4.81 mg/g), but the adsorption capacity for NO2- in the gastric environment (84.68%) was significantly higher than that in the intestinal environment (16.21%). The SDF of pear pomace seem to have good physical and chemical functional properties, and this study provides a theoretical basis for the high-value utilization of pear pomace.