绿豆皮纳米纤维素对浓缩乳清蛋白可食膜性能的影响

Effects of Mung Bean Hull Nanocrystalline Cellulose on the Performance of Whey Protein Concentrate Edible Film

摘要:

以绿豆皮纤维素为原料，采用硫酸水解法制备绿豆皮纳米纤维素并将其应用到浓缩乳清蛋白可食膜中，研究了绿豆皮纳米纤维素的微观形貌、结晶结构以及绿豆皮纳米纤维素添加量对浓缩乳清蛋白膜抗拉强度、断裂伸长率、氧气透过率、水蒸气透过系数、透光率及微观结构的影响。结果表明：绿豆皮纳米纤维素为棒状结构，长度约为100~200 nm，直径约为10~20 nm，且保持典型的纤维素Ⅰ型结构，结晶度较高；绿豆皮纳米纤维素与浓缩乳清蛋白有很好的相容性；当绿豆皮纳米纤维素添加量为1%时，膜的水蒸气透过系数达到最小值，为2.67×10-13 g/(cm?s?Pa)；膜的透光率达到最大值，为39.31%；此时膜表面较为平整均匀。当绿豆皮纳米纤维素添加量为2%时，膜的抗拉强度最大为1.41 MPa，此时断裂伸长率为139.8%；膜的氧气透过率达到最小值，为1.8×10-5 cm3/(m2?d?Pa)。绿豆皮纳米纤维素的添加能够有效的提高浓缩乳清蛋白膜的性能。

Abstract:

Mung bean hull cellulose was used as the raw material to obtain nanocrystalline cellulose by sulfuric acid hydrolysis, which was applied to prepare a whey protein concentrate film. The morphology and crystalline structure of mung bean hull nanocrystalline cellulose and the effects of the amount of added mung bean hull nanocrystalline cellulose on the tensile strength, elongation at break, oxygen permeability, water vapor permeability, transmittance, and microstructure properties of whey protein concentrate films were evaluated. The results showed that the mung bean hull cellulose nanocrystals had a rod-shaped structure with the length ranging from 100 to 200 nm and the diameter ranging from 10 to 20 nm. In addition, the typical cellulose I structure was maintained, with relatively high crystallinity. Mung bean hull nanocrystalline cellulose had good compatibility with the whey protein concentrate. When the content of mung bean hull nanocrystalline cellulose was 1%, the lowest water vapor permeability [2.67 × 10-13 g/(cm?s?Pa)] and the highest transmittance of the films were reached, and the surface of the whey protein concentrate film was smooth and homogeneous. When the content of mung bean hull nanocrystalline cellulose was 2%, the tensile strength was highest (1.41 MPa), the elongation at break was 139.8%, and the lowest oxygen permeability [1.8 × 10-5cm3/(m2?d?Pa)] was obtained. The addition of mung bean hull nanocrystalline cellulose can effectively improve the performance of whey protein concentrate films.