壳聚糖醋酸盐的制备及其油脂吸附性能研究

The Preparation of Chitosan Acetate Salt and Its Fat-Binding Capacity

摘要:

采用半湿研磨法制备了壳聚糖醋酸盐（Ch-Ac），对其结构、理化性质进行了表征和测定。以食用油为吸附对象，探讨了搅拌速度、温度、介质pH等因素对Ch-Ac油脂吸附性能的影响，通过正交实验确定了Ch-Ac油脂吸附的最佳条件。实验结果表明：（1）Ch-Ac改善了壳聚糖的溶解性能而且具有较强的缓冲能力；（2）搅拌速度1000 r/min、温度25 ℃、介质pH=5的条件下，Ch-Ac的油脂吸附量（OBC）高达168.72 g/g，是壳聚糖OBC的10倍;（3）在pH=2~10的介质中，Ch-Ac的OBC均大于133.23 g/g，模拟人体胃肠pH环境连续变化，Ch-Ac的OBC为148.13 g/g。结果表明Ch-Ac的油脂吸附能力受介质pH影响较小。固体Ch-Ac制备方法简单、绿色环保，油脂吸附效率高，可在含油废水处理和降脂保健品等方面得到应用。

Abstract:

Chitosan acetate (Ch-Ac) was prepared by a semi-wet grinding method. The structure and physicochemical properties of Ch-Ac were characterized and determined. Using edible oil as the adsorption target, the effects of stirring speed, temperature and medium pH on the oil-binding capacity (OBC) of Ch-Ac were investigated. Basing on orthogonal experiments, the optimum conditions for the binding of oil by Ch-Ac were established. The experimental results were as follows: (1) The solubility of chitosan was improved in the form of Ch-Ac and Ch-Ac exhibited a strong buffering capacity; (2) The OBC of Ch-Ac was up to 168.72 g/g, which was 10 times as high as that of chitosan, at a stirring speed of 1000 r/min, absorption temperature of 25 ℃ and pH 5. (3) The OBC of Ch-Ac was greater than 133.23 g/g in a medium with a pH of 2~10, while reaching 148.13 g/g in a simulated human gastrointestinal environment with a continually changing pH. These results indicated that the OBC of Ch-Ac was less affected by the medium pH. The preparation method of solid Ch-Ac is simple, green and environmentally friendly. The obtained Ch-Ac has high OBC thus can be applied to treat oil-containing waste water and develop lipid-lowering health care products.