摘要
A visual pH indicator through purple cabbage dye is selected to test the freshness of venison.Chitosan and cassava starch of an equal weight were used to prepare the film-forming matrix of the indicator.The crystallization of natural purple cabbage dyes with a weight ratio of 5%,10%,20%and 40%were added to the matrix,respectively.The pH color test showed that the natural purple cabbage lyophilized powder with a weight ratio of 40%was the best for the pH indicator,which was used to test the freshness of venison stored at 4℃.The total bacterial count,volatile basic nitrogen(TVB-N)and thiobarbituric acid(TBA)of venison were tested through an experiment.When stored at under 4℃,a significant color change of the indicator from pink to blue-green was shown when the total amount of volatile basic nitrogen(TVB-N)(22.78 mg/100 g)exceeded the critical value(20 mg/100 g).The test result showed that the indicator was very sensitive to pH value and it would help customers identify the freshness of venison.
基金
Basic Scientific Research Project 2572020DF01 of Northeast Forestry University
Fundamental Research Funds for Higher Education Institutions of Heilongjiang Province(135309513,135309109).
