A simple, rapid and sensitive method for monitoring contamination of aseptically processed tomato paste

Abstract

A simple, rapid and sensitive method for the detection of microbial contamination of the system of aseptically processing tomato paste has been developed. The method involves the rapid growth of any lactobacilli present in the product and detection of metabolites produced by these micro-organisms. The metabolites used are acetoin, diacetyl, carbon dioxide and lactic acid. It was found that with this method it is possible to detect the presence of both homofermentative and heterofermentative lactobacilli within 10-25 hr, depending on the level of contamination.

Noninvasive, Nondestructive Measurement of Tomato Concentrate Spoilage in Large‐Volume Aseptic Packages

“…If the wild‐type samples were initially exposed to a contaminant more than 5 days before arrival, no drastic increase in the T 1 or T 2 values would have been expected over the course of the study. During the process of spoilage, the viscosity of tomato concentrate can change as it is broken down by fermentation caused by lactic acid bacteria (Arkoun, Abbas, & T. K., ; Juven & Weisslowicz, ; Mallidis & Samaras, ; Schaffner & Beuchat, ). Other spoilage detection methods involve measuring the viscosity of the sample; however, these methods require that the container be opened for analysis.…”

Changes in tomato pulp quality caused by lactic acid bacteria

“…Lactic acid bacteria are microorganisms of spoilage significance in the processing of tomato products. They impart flavours and odours which have been defined as similar to 'buttermilk' and are present on and in the fruit on arrival at the plant; they grow well in single-strength and in partially concentrated tomato juice (Vicini et al, 1988; Mallidis & Samaras, 1987).…”

Thermal treatment of aseptically processed tomato paste

“…Lactic acid bacteria and spore-forming bacteria are the main groups of microorganisms involved in the spoilage of tomato products (York et al, 1975;Luster, 1978;Juven & Weisslowicz, 1981;Juven et al, 1983;Mallidis & Samaras, 1987). Lactic acid bacteria are rapidly killed by a mild heat treatment and are mainly involved in post-process contamination of the product.…”