Preventing fungal spoilage from raw materials to final product: innovative preservation techniques for fruit fillings

Spoilage fungi are a significant cause of financial loss in the food and beverage industry each year. These fungi thrive in challenging environments characterized by low acidity, low water activity and high sugar content, all of which are common in fruit fillings used in pastry products. Fruit fillings are therefore highly susceptible to fungal spoilage. Fungal growth can cause sensory defects in foods, such as changes in appearance, odor, flavor or texture, and can pose health risks due to the production of mycotoxins by certain mold species. To reduce food loss and waste and extend product shelf-life, it is critical that we prevent fungal spoilage. Synthetic chemicals such as sorbic acid and potassium sorbate are commonly used as preservatives to prevent fungal spoilage. However, with consumer demand for ‘natural’ and ‘chemical-free’ foods, research into clean-label preservative alternatives to replace chemical preservatives has increased. The objectives of this review are (i) to provide an overview of the sources of fungal contamination in fruit filling production systems, from pre-harvest of raw materials to storage of the final product, and to identify key control factors; and (ii) to discuss preservation techniques (both conventional and novel) that can prevent fungal growth and extend the shelf-life of fruit fillings.