Aims:  To investigate antifungal activity produced by lactic acid bacteria (LAB) isolated from malted cereals and to determine if such LAB have the capacity to prevent fungal growth in a particular food model system. Methods and Results:  The effect of pH, temperature and carbon source on production of antifungal activity by four LAB was determined. Pediococcus pentosaceus was used to conduct a trial to determine if it is feasible to eliminate Penicillium expansum, the mould responsible for apple rot, using an apple model. Penicillium expansum was incapable of growth during the trial on apple‐based agar plates inoculated with the antifungal‐producing culture, whereas the mould did grow on apple plates inoculated with an LAB possessing no antifungal activity. Conclusion:  Partial characterization of the antifungal compounds indicates that their activity is likely to be because of production of antifungal peptides. The trial conducted showed that the antifungal culture has the ability to prevent growth of the mould involved in apple spoilage, using apples as a model. Significance and Impact of the study:  The ability of an LAB to prevent growth of Pen. expansum using the apple model suggests that these antifungal LAB have potential applications in the food industry to prevent fungal spoilage of food.