Hazelnuts as Possible Substrate for Aflatoxin Production 1.
V Sanchis1, Ma L Quilez1, R Viladrich1
1Laboratorio de Microbiología, Dep. Tecnología de Alimentos, Universitat Politècnica de Catalunya, Rovira Roure 177, 25006-Lleida, Spain, and Laboratorio de Química, Dep. Producción Vegetal, Universitat Politecnica de Catalunya, Rovira Roure 177, 25006-Lleida, Spain.
Journal of Food Protection
|April 14, 2019
Summary
Raw hazelnuts are universally contaminated with fungi. While naturally aflatoxin-free, optimal conditions and Aspergillus parasiticus inoculation led to high aflatoxin levels, with potassium sorbate enhancing production.
Area of Science:
- Food microbiology
- Mycology
- Food safety
Background:
- Fungal contamination and mycotoxin production in food commodities like hazelnuts pose significant health risks.
- Understanding the factors influencing fungal growth and aflatoxin biosynthesis is crucial for developing effective control strategies.
Purpose of the Study:
- To investigate fungal contamination in commercial hazelnuts.
- To determine the impact of water activity, temperature, and potassium sorbate on fungal growth and aflatoxin production in hazelnuts.
Main Methods:
- Analysis of fungal contamination in 100% of raw hazelnut samples.
- Inoculation of hazelnuts with Aspergillus parasiticus under varying water activity and temperature conditions.
- Assessment of potassium sorbate's effect on fungal growth and aflatoxin levels.
Main Results:
- All tested raw hazelnut samples exhibited fungal contamination.
- Optimal water activity and temperature conditions, coupled with Aspergillus parasiticus inoculation, resulted in significant aflatoxin production.
- Subinhibitory concentrations of potassium sorbate appeared to stimulate aflatoxin production despite inhibiting fungal growth.
Conclusions:
- Raw hazelnuts are consistently susceptible to fungal contamination.
- Environmental factors and specific fungal strains are critical for aflatoxin development in hazelnuts.
- Potassium sorbate's role in aflatoxin production warrants further investigation due to its complex effects.
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