Temperature and water activity minima for growth of spoilage moulds from meat

Area of Science:

• Food Microbiology
• Mycology
• Food Safety

Background:

• Mould spoilage significantly impacts meat quality and safety.
• Understanding the specific fungal species and their growth parameters is crucial for effective preservation.

Purpose of the Study:

• To identify fungal species responsible for meat spoilage other than black spot.
• To determine the minimum growth temperatures and xerotolerance of isolated fungi.
• To establish the practical temperature limit for fungal growth on meat.

Main Methods:

• Isolation and identification of fungal species from spoiled meat.
• Determination of minimum growth temperatures and xerotolerance under laboratory conditions.

Main Results:

• Five fungal species were identified: Chrysosporium pannorum, Acremonium sp., Penicillium corylophilum, Thamnidium elegans, and Mucor racemosus.
• Chrysosporium pannorum, Acremonium sp., and P. corylophilum exhibited moderate xerotolerance with minimum growth temperatures between -5°C and -2°C.
• Thamnidium elegans showed a low minimum growth temperature (-10°C) but limited xerotolerance, while Mucor racemosus had poor cold tolerance and grew above 3°C.
• The practical limiting temperature for mould growth on meat was determined to be -5°C.

Conclusions:

• Mould spoilage on frozen meat indicates that surface temperatures have likely risen above 0°C.
• Specific fungal species have varying tolerances to cold and low water activity, influencing spoilage patterns.
• Effective cold chain management is essential to prevent fungal growth and spoilage in frozen meat products.