Effects of Initial Nitrite Level, Heating and Storage on Residual Nitrite and Spoilage of Canned Ham Roll

Canned ham rolls with initial nitrite levels of 0, 125, 200, 300 and 400 mg/kg were processed to an Fo of 1.07 and 1.49 and stored for 8 months. Ham rolls before processing contained 105–107 cfu/g total bacteria and less than 3 MPN/g of putrefactive anaerobic bacterial spores. The initial nitrite level, the storage time and the heat treatment significantly affected residual nitrite in the product. Samples stored for 1 and 3 days had significantly higher residual nitrite levels than those stored for 6–31 days. Samples processed with 0, 125 and 200 mg/kg nitrites contained significantly lowered residual nitrite levels than those formulated with 300 and 400 mg/kg nitrite. Samples heated to an Fo of 1.07 contained less residual nitrite (P ≤ 0.05) than those heated to Fo 1.49. No swelled cans were observed after 8 months of storage and the nitrosamine levels detected in the samples were lower than the safety limit proposed by Pneussman (1974).