酱油渣是营养价值丰富但又未能合理利用的工业副产物，从中回收膳食纤维具有废物利用和环境保护的意义。本文利用自主研发的低温连续相变萃取技术制备酱油渣不溶性膳食纤维（IDF），在前期单因素试验基础上，以IDF得率为指标，对技术参数进行响应面优化，然后辅以水洗、酶解工艺对IDF进行纯化。同时，本文研究了酱油渣IDF的功能特性，并通过电镜初步阐释其微观形貌与功能特性的机理关系。结果表明，最佳技术条件为萃取压力0.5 MPa、萃取温度45 ℃、萃取时间67 min、原料颗粒度50目，制备得到油脂含量<1%的粗IDF。再辅以纯化工艺，酱油渣IDF的纯度达70.9±0.28%。功能测试表明，酱渣IDF具有优良的膳食纤维特性，其持水力、膨胀力和吸油力分别为6.65±0.07 g/g、5.83±0.11 mL/g和2.23±0.03 g/g。与市售大豆IDF产品相比，其吸油力尤为显著。扫描电镜表明，酱油渣IDF良好功能特性与该技术下其形成的网状疏松纤维骨架结构有关。

Soy sauce residues (SSR) were the main by-products of soy sauce fermentation, which contained a large amount of valuable components but failed to be reused reasonablely. Recycling the dietary fiber (DF) from SSR could make good use of the waste and remedy the issue of environmental hazards. The SSR insoluble dietary fiber (IDF) was prepared by a novel method of low temperature continuous phase transition extraction. Based on previous single factor experiments, the process parameters were optimized through the response surface methodology (RSM) for maximum IDF yield. Washing and enzymolysis were accompanied for purification. The functional characteristics of SSR IDF were investigated. In combination with the scanning electron microscopy (SEM), mechanism of the relationship between its microstructure and functional characteristics was explained preliminarily. Results showed that the best extraction conditions were 50 mesh raw material ,extraction regent n-butane solvent, extraction pressure 0.5 MPa, extraction temperature, 45 ℃ and extraction time 67 min, under which the oil content of obtained IDF was less than 1%. After purification, the purity could reach as high as 70.9±0.28%. Functional tests showed that SSR IDF had good features, and water holding capacity, expansibility and oil binging ability were 6.65±0.07 g/g, 5.83±0.11 mL/g and 2.23±0.03 g/g, respectively. Compared with commercially available soybean IDF products, the oil binging ability of SSR IDF was paticulary significant. From the SEM figures, the good functional characteristics of SSR IDF were related to its loose structure formed by the cellulose.

国家自然科学基金（31301445）