EFFECT OF HEADSPACE OXYGEN AND FILMS OF DIFFERENT OXYGEN TRANSMISSION RATE ON TOXIN PRODUCTION BY CLOSTRIDIUM BOTULINUM TYPE E IN RAINBOW TROUT FILLETS STORED UNDER MODIFIED ATMOSPHERES

Abstract

Studies were conducted to determine the effect of various levels of headspace oxygen (0–100%, balance CO2) or film oxygen transmission rate (OTR) on the time to toxicity in modified atmosphere packaged (MAP) fresh trout fillets challenged with C. botulinum type E (102 spore/g) and stored under moderate temperature abuse conditions (12C). In all cases, trout were toxic within 5 days, irrespective of the initial levels of oxygen in the package headspace. However, spoilage preceded toxigenesis. Packaging of trout fillets in low gas barrier films, with OTRs ranging from 4,000 to 10,000 cc/m2/day at 24C and 0% relative humidity, also had no effect on time to toxicity in all MAP trout fillets. All fillets were toxic within 4–5 days and spoilage again preceded toxigenesis. This study has shown that the addition of headspace O2, either directly to a package or indirectly by using a low gas barrier film, had no influence on the time to toxigenesis or spoilage. Additional barriers, other than headspace O2 or film transmission rate, need to be considered to ensure the safety of MAP trout fillets, particularty at moderate temperature abuse conditions.

EFFECT OF MODIFIED ATMOSPHERE PACKAGING ON CHEMICAL, TEXTURAL, MICROBIOLOGICAL AND SENSORY QUALITY OF SEER FISH (SCOMBEROMORUS COMMERSON) STEAKS PACKAGED IN THERMOFORMED TRAYS AT 0–2C

“…After that, microbial growth resulted in increased CO 2 concentration. These results confirm a previous study by Dufresne et al. (2000).…”

EFFECT OF POTASSIUM SORBATE AND MODIFIED ATMOSPHERE PACKAGING ON THE SHELF-LIFE EXTENSION OF SEER FISH (SCOMBEROMORUS COMMERSON)STEAKS DURING ICED STORAGE

“…In MAP stored seer fish, the decrease was caused by gas being absorbed into the tissue. These results confirm previous studies with Daifas et al (1999) and Dufresne et al (2000). O 2 concentration decreased significantly (P < 0.05) from 20.9 to 0.0006% on day 14, i.e., on rejection day for the control pack (Fig.…”

Shelf Life and Safety Concerns of Bakery Products—A Review

“…There is evidence that toxin may be formed in foods containing high levels of oxygen in the package headspace (20-100% v/v) and even in food stored aerobically. 53,80,228 Once germination is initiated, growth may be rapid, as the redox potential is rapidly reduced. Furthermore, pockets of food may be sufficiently anaerobic or have redox potentials conducive to germination and growth.…”