乳酸根插层水滑石/果胶膜的制备及应用

Preparation and Application of Hydrotalctitel Pectin Film Intercalated with Lactate

目的研究一种新型的保鲜膜,并探究其对鱼肉保鲜效果和货架期的影响。方法采用离子交换法将乳酸根插层到水滑石的层板中,制备出一种新型的复合纳米材料乳酸根–插层水滑石(MgAl–SL–LDHs),利用红外光谱仪进行表征。再以果胶为成膜材料、甘油为增塑剂、氯化钙为增稠剂、蜂蜡、Span–40、Tween–80黏性液体作为表面活性剂,MgAl–SL–LDHs作为填充材料制备出一种复合膜,并测定膜的拉伸强度、断裂伸长率、透光性和水蒸气透过量。将鱼肉用不同质量分数的MgAl–SL–LDHs薄膜包裹后在4℃下贮藏,每4天测定菌落总数和挥发性盐基氮。结果由正交试验得出制备膜的最佳工艺,即果胶、甘油、氯化钙质量分数为2.5%、1%、2%。质量分数为0.3%和0.5%MgAl–SL–LDHs包裹的鱼肉第14天菌落总数达到国家标准6 lg(CFU/g),第16天TVB–N的数值还未达到国家标准20 mg/hg。结论此种保鲜膜在鲤鱼的保鲜中有一定的效果,可延长货架期6 d左右。

The work aims to prepare a new type of cling film and explore its effect on fish preservation and goods holiday.A novel nanomaterial lactate intercalated hydrotalcite(MgAl-SL-LDHs)was prepared by intercalating sodium lactate into the laminate by ion exchange method.It was characterized by infrared spectrometer.A composite membrane was prepared with pectin as film-forming material,glycerol as plasticizer,calcium chloride as thickener,beeswax,span-40,Tween-80 viscous liquid as surfactant and MgAl-SL-LDHs as filling material.The tensile strength,elongation at break,light transmittance and water vapor permeability of the films were measured.The fish was wrapped in MgAl-SL-LDHs films with different mass concentrations and stored at 4℃,colony count and volatile base nitrogen were measured every 4 days.The optimum process for preparing the membrane was obtained by orthogonal test,added with a mass concentration of 2.5%pectin,1%glycerol,2%calcium chloride.Fish wrapped in 0.3%and 0.5%MgAl-SL-LDHs reached the national standard 6 lg(CFU/g)on the 14th day,the value of TVB-N on the 16th day did not reach the national standard 20 mg/hg.This kind of cling film has a certain effect in the preservation of carp,and it can extend the shelf life by about 6 days.