The concentration of mold in bread and bakery products does not cause alarm from a food safety point of view and is therefore without appropriate regulation, at the European and national levels. Insight.
1) Molds in food, formation and inhibition.
It is generally accepted that foods with a pH < 3.9 and a water activity < 0.88 do not support the development of pathogenic microorganisms, regardless of storage conditions (e.g., temperature, atmosphere). Even under these conditions, however, molds can develop. The different conditions for inhibiting the growth of any microorganism are:
(i) water activity < 0.88,
(ii) pH < 3.9,
(iii) water activity ≤ 0.96 and pH ≤ 4.2,
(iv) water activity ≤ 0.92 and pH ≤ 4.6,
(v) water activity ≤ 0.90 and pH ≤ 5.0.
Other factors that affect mold growth are the nature of the food, processing and storage temperature, and proper storage conditions. Packaging that lacks a watertight seal, i.e., is not fully sealed, could promote moisture buildup and encourage mold growth.
2) Molds in bread, reference values.
2.1) Hygiene and mold package.
Reg. EC no. 852/2004, so called Hygiene 1, prescribes the adoption of good food hygiene practice to prevent contamination that may affect food safety (Annex I, Part A, Section I, Paragraph 2).
The prevention of mold growth is also mentioned as a hygienic pre-requisite to which attention should be paid, with particular regard to the surfaces and ceilings of food production establishments.
2.2) Microbiological criteria and contaminants.
Reg. EC no. 2073/2005, on microbiological requirements in food, does not report any requirements in relation to molds, in any food. This regulation, on the other hand, represents a minimum common denominator on the major microbiological criteria.
Reg. EC no. 1881/2006 – which defines the maximum levels of certain contaminants in food( lastupdated 3.5.22) – instead defines the specific limits of two mycotoxins – deoxynivalenol (DON) and zearalenone (ZEA) – in bread. (1)
2.3) OECD Guidelines.
OECD guidelines on the limits of microbiological contaminants report the ubiquitousness of molds (along with yeasts and bacteria) in foods, subject to the assumption that they are sterilized.
Indeed, molds can also develop under conditions unfavorable for other microorganisms (e.g., low water activity, pH, high sugar and/or salt concentrations). And several mold species are resistant to heat treatment.
OECD has proposed < 1,000 CFU/g (or ml) as the reference value for mold screening in food. (2) In line with Health Canada ‘s proposed level of microbial contamination.
2.4) FSAI(Food Safety Authority of Ireland).
A recent scientific study (Ferone et al., 2020), in reviewing different methods of identifying microbial contaminants in food, (3) reported acceptability values in ready-to-eat products that have been taken up as reference values by the Food Safety Authority of Ireland (FSAI).
Total viable count (TVC)-reporting the sum of yeast, mold and bacteria-was considered acceptable at levels < 10,000 CFU/g, borderline at levels between 10,000 – ≤ 1,000,000 CFU/g, unsatisfactory at levels > of 1,000,000 CFU/g. And the most updated version of the aforementioned FSAI standard reports the same values, even for the bakery category. (4)
3) EFSA, no alarm on mold.
The European Food Safety Authority, in its opinion on date marking (EFSA, 2020), confirmed the prevalence ability of molds over other microorganisms, even under extreme conditions. However, the presence of molds (on bread and other foods) does not present a concrete health risk to consumers, according to EFSA.
Moreover, the formation of mycelia on the surface of the product is clearly visible, and the risk of their ingestion is highly unlikely. Sensory significant changes were attributed to mold concentrations in the range of 105-106 CFU/g (5,6).
4) Interim Conclusions
Bread and baked goods are susceptible to contamination by various fungal species, including Alternaria, Aspergillus, Cladosporium, Geotrichum candidum, Mucor, Neuropspora sitophila, Penicillium, Rhizopus stolonifera, and Thamnidium elegans. Attention in self-control should be focused primarily on mycotoxins and potentially pathogenic mold species (e.g., Penicillium crustosum).
The possible presence of mold in bread and bakery products does not in itself integrate any food safety risk, outside of only the assumptions of their characterization and identification of mycotoxins or other pathogens. In which cases the risk assessment will also disregard the presence or absence of legal limits. Visibly ‘moldy’ bread and baked goods are still subject to corrective action as unfit for human consumption. (7)
Dario Dongo
Notes
(1) Marta Strinati. Mycotoxins, the invisible evil. ABC. FT (Food Times). 5/24/19, https://www.greatitalianfoodtrade.it/sicurezza/micotossine-il-male-invisibile-l-abc
(2) OECD, Issue Paper on Microbial Contaminants Limits for Microbial Pest Control Products. https://www.oecd.org/env/oecd-issue-paper-on-microbial-contaminants-limits-for-microbial-pest-control-products-9789264221642-en.htm
(3) Ferone et al. (2020). Microbial detection and identification methods: Bench top assays to omics approaches. Compr. Rev. Food Sci. Food Saf. 19:3106–3129, https://doi.org/10.1111/1541-4337.12618
(4) FSAI (2020). Guidelines for the Interpretation of Results of Microbiological Testing of Ready-to-Eat Foods Placed on the Market. Revision 4. ISBN: 0-9539183-5-1. https://www.fsai.ie/WorkArea/DownloadAsset.aspx?id=16771
(5) EFSA BIOHAZ Panel (2020). Guidance on date marking and related food information: part 1 (date marking). EFSA Journal 18(12):6306, https://doi.org/10.2903/j.efsa.2020.6306
(6) Dario Dongo. Expiration date and TMC, EFSA guidelines for reducing food waste. FT (Food Times). 12/20/20, https://www.greatitalianfoodtrade.it/etichette/data-di-scadenza-e-tmc-linee-guida-efsa-per-la-riduzione-degli-sprechi-alimentari
(7) See reg. EC 178/02, Article 14. For more details see theebook ‘Food Safety, Mandatory Rules and Voluntary Standards ‘ https://www.greatitalianfoodtrade.it/libri/sicurezza-alimentare-regole-cogenti-e-norme-volontarie-il-nuovo-libro-di-dario-dongo
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
