Isolation and Characterization of Facultative Anaerobes Involved in Canned Food Spoilage and Examining the Effect of Different Preservatives

Facultative Anaerobes Involved in Canned Food Spoilage

Abstract

Spoilage of canned food is a major issue worldwide. The major cause of spoilage of food in cans is the bacterial contamination that happens due to mishandling, damage, or improper packaging treatment. To avoid spoilage and increase the shelf-life of canned food, various food preservatives are used. However, it is ideal to use specific preservatives for specific foods. There is a need to check the types of organisms causing the food spoilage and the preservatives that can be used against them. The current study focuses on the isolation of facultative anaerobic bacterial species which are specifically involved in spoilage of canned food items, their characterization and effectiveness of different food preservatives against them. For this propose samples were taken from expired peas, meat, and pineapple cans. Each sample was cultured on Acid agar, Mannitol salt agar, DTPB agar, and EMB agar. The bacterial colonies were purified and characterized morphologically and biochemically. The effectiveness of food preservatives such as ascorbic acid, sodium benzoate, sodium propionic acid and sodium nitrite was analyzed on the isolated strains. Selected isolates were identified through 16S rRNA gene sequencing. Facultative anaerobes belonging to the genera Leucobacter and Exiguobacterium were identified in the expired food cans. Among the tested food preservatives, ascorbic acid was proved highly effective as it inhibited the growth of these organisms. Facultative anaerobes play an important role in canned food spoilage and by utilizing specific food preservatives these microbes can be minimized.