USE OF CHEMICALS AND PACKAGING MATERIALS TO PROLONG THE SHELF-LIFE OF FRIED PORK SAUSAGE (SAI-OUA)

Abstract

Fried pork Sausage (Sai-oua) is one of traditional foods of northern Thailand. Its production involves mixing small pieces of chunk pork, bacon and lard together with sauce, vinegar, salt and spices. This work aimed to extend the shelf-life of the Sai-oua by addition 0.1per cent of sodium propionate, potassium sorbate sodium benzoate in the recipe and packed tightly in natural casing. It is fried or roasted and packed in polyethylene bag and saran in order to study their keeping qualities when kept in 20-26 degree celcius. The physical, chemical and microbiological changes of the product during storage at 0,4,11 days were monitored. The food compositions of the product were 19% protein, 33% fat, 2.5% ash and 38% water. The initial pH was 5.6 After storage for 4 days, most treatments show edsignificantly increase in peroxide values and microbial counts. The treatments using propionate and benzoate as preservatives were spoiled by moulds after 4 days of storage. The treatments using sorbate showed satisfactory appearance when stored at the same poriod but were spoiled by moulds after 11 days. In order to confirm this, total bacterial count, mesophilic aerobic count, Escherichia coli, Staphylococcus aureus, Clostridium perfringens, Salmonella, Vibrio cholerae and total volatile nitrogen in every treatment was also studied. There was not much potential to spoil in treatments using potassium sorbate packed in saran when compared with that of using the same chemical and packed in polyethylene bags. Peroxide value in each treatment was lower than 5 mEq per kilogram. The salt and salt penetration in each treatment were also studied.