Incorporations of blueberry extracts into soybean-protein-isolate film preserve qualities of packaged lard

P>The effect of blueberry-extract incorporation into soybean-protein-isolate edible film on the quality of packaged lard was compared with vitamin E or butylated hydroxyl anisole (BHA) incorporations individually during the storage at 36 degrees C and relative humidity of 40% for 5 weeks. Blueberry-extract incorporations into soybean-protein-isolate film showed a greater tensile strength, lower water vapour permeability and lower oxygen permeability than vitamin E or BHA incorporations individually. On the other hand, the antioxidant capacity of soybean-protein-isolate film incorporated with the blueberry extract was greater than that incorporated with vitamin E and similar to that incorporated with BHA. Moreover, soybean-protein-isolate film incorporated with the blueberry extract showed a greater capacity to delay the lard hydrolysis than that incorporated with BHA, and a similar capacity to that incorporated with vitamin E. Consequently, blueberry-extract incorporations into soybean-protein-isolate film not only improved mechanical and barrier properties, but also delayed the oxidation and hydrolysis of packaged lard. Therefore, blueberry-extract incorporations into soybean-protein-isolate films have potential as a packaging material which will preserve the qualities of stored lard.