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With Christmas right around the corner, sales in turkey meat are sure to soar and those who purchase well in advance will be freezing their meat until the big day. Whilst there is no issue with freezing turkey meat, there is an issue with re-freezing as the freeze-thawing process spoils the meat, rendering it unsuitable for consumption.
There has been a reported rise in demand for turkey meat, which leads to mass production [1]. Whilst mass production does somewhat satisfy the demand, how the meat is produced is not always hygienic and ethical. This is because although farmers want to meet the demand, they may not have the space nor the finances to achieve this, so resort to keeping large numbers of turkeys in small areas. Poor and unsanitary conditions increase the risk of contamination and they become more susceptible to disease [1]. Without veterinary treatment, the meat could already be spoiled before it makes it to the shelves and re-freezing the meat could then further damage the quality [1]. However, consumers should not worry as microbiological safety is checked prior to sale to shops/farms by testing the levels of microorganisms, including Escherichia coli, Staphylococcus aureus, Salmonella, and facultative anaerobes [1].
So, how does refreezing harm the meat? Repeated freeze-thawing triggers autolytic processes, which causes cellular and tissue damage [1]. This leads to a disruption of the muscular structure as well as the production of lactic acid [1]. As the muscular structure is now altered, microbial dysbiosis of the microflora occurs and the growth of pathogenic bacteria is promoted [1]. In a 2022 study, smear-prints of re-defrosted meat showed damage to the muscle fibres, which disrupted the sarcolemma integrity [1]. The sarcolemma contributes to microflora development, so as expected, damage leads to microbial dysbiosis, creating a more favourable environment for pathogenic microorganisms [1]. This is supported by the fact that out of all the parts of the turkey, the wing had the most microbial contamination, due to increased muscle mass [1].
Evidence into the negative effect of re-freezing on the quality of turkey meat was demonstrated in this paper, which showed that re-frozen meat had a 14.5 times higher microbial count than chilled turkey meat and an 8.4 times higher count than defrosted turkey meat [1]. These counts surpass the permitted levels recommended by regulatory bodies, meaning that after re-freezing, the meat would undoubtably be unconsumable [1].
Further research into this area is required before full conclusions are made, however, it is beneficial to take note of present research and exercise caution with regards to re-freezing your Christmas dinner.
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Written by DWS Microbiologist Kirsty McTear
References:
- STEKOLNIKOV, A. et al. (2022) “Turkey Meat Hygiene and biological safety assessment after defrosting,” Online Journal of Animal and Feed Research, 12(1), pp. 31–36. Available at: https://doi.org/10.51227/ojafr.2022.5.
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