Food Safety and Shelf Life Improvement of Minimally Processed Strawberries

Strawberries have been consistently within the top 10 pesticide residue-containing commodities in the last years. In this work, the safety of ready-to-eat strawberries in terms of pesticide residues was evaluated throughout its shelf life. The effect of conventional minimal processing operations (washing, calyx removal, and disinfection) and of modified atmosphere packaging (MAP) on the pesticide residue content and its evolution throughout the shelf life was investigated. Different pesticides, using a validated multiresidue method, in concentration levels between 0.014 +/- 0.007 and 1.78 +/- 0.008 mg kg(-1) were found in commercial strawberries right after harvest. Fruit calyx removal, washing, and disinfection contributed to improvement of the product safety because the pesticide residue concentration decreased up to 80% of the original value. No influence of the atmosphere on the pesticide concentration was observed. Minimal processing and MAP contributed to the chemical safety of strawberries in terms of pesticide residues, reducing the residue concentration by more than 80%, while allowing shelf life extension.