该文以酿酒葡萄皮为原料，采用热酸法和酶法提取水溶性膳食纤维（Soluble Dietary fiber，SDF），测定其组分及含量，并利用两种水溶性膳食纤维SDF1（热酸法提取）、SDF2（酶法提取）制备水包油型乳液，以粒径分布跨度Span值表示乳液均一度，体积平均粒径大小D4,3值为指标，研究其乳化稳定性。结果显示：SDF2的蛋白质含量、半乳糖醛酸、中性糖、甲酯化度和乙酰化度以及分子量大小都低于SDF1；将乳液在4 ℃、20 ℃和60 ℃条件下分别储存15 d后，发现SDF1样品乳液的D4,3从初始值1.10 μm分别增加到4.29 μm（4 ℃）、5.72 μm（20 ℃）以及7.57 μm（60 ℃），表明低温条件下SDF1乳液的稳定性最好；SDF2样品乳液D4,3从3.73 μm增加到17.7 μm（4 ℃）、15.30 μm（20 ℃）以及12.47 μm（60 ℃），最后D4,3均达到12 μm以上，表明SDF2样品乳液整体稳定性差；SDF1的Span值为（3.37~4.18），显著大于SDF2（2.84~3.52），故SDF2样品乳液的均一性优于SDF1。研究结果表明，酶处理后的SDF乳化活性显著下降。因此保证SDF中蛋白质和中性糖含量等各种组分的完整性能够显著提高SDF的乳化稳定性。

Soluble dietary fiber (SDF) was obtained from wine grape skin by two different methods, viz. hot acid and enzymatic methods, and the chemical compositions of the two types of water-soluble dietary fiber, viz. SDF1 (extracted via hot acid method) and SDF2 (obtained using enzyme method), were determined. Subsequently, SDF1 and SDF2 were used to prepare oil-in-water emulsions. The emulsion uniformity was examined using the particle size distribution, while the emulsifying stability was determined using the volume-weighted mean diameter (D4,3). The protein, galacturonic acid, and neutral sugar contents, degrees of methylation and acetylation, and molecular weight of SDF2 are lower than those of SDF1. The emulsions were stored separately for 15 d at 4, 20, and 60 ℃. After storage, the D4,3 value of SDF1 emulsion increases from 1.10 μm to 4.29 μm (4 ℃), 5.72 μm (20 ℃), and 7.57 μm (60 ℃), indicating the higher stability of SDF1 emulsion at low temperatures. After storage, the D4,3 value of SDF2 emulsion increases from 3.73 μm to 17.7 μm (4 ℃), 15.30 μm (20 ℃), and 12.47 μm (60 ℃). Eventually, the values of SDF2 emulsions stored at different temperatures reach ≥12 μm, indicating an unsatisfactory overall stability of SDF2 emulsions. The span of SDF1 ranges from 3.37 to 4.18, which is significantly higher than that of SDF2 (2.84~3.52); therefore, SDF2 is more homogeneous than SDF1. After enzyme treatment, the emulsifying activity of SDF decreases significantly. Hence, the emulsifying stability of SDF can be considerably improved by ensuring the integrity of components such as proteins and neutral sugars in SDF.

新疆维吾尔自治区重大科技专项（2017A01001-4）