Sodium alginate-cinnamon essential oil coated apples and pears: Variability of Aspergillus carbonarius growth and ochratoxin A production

The scope of the present study was to use selected fruits as model foods (wounded skin or slices of apples and pears), for the in situ assessment of the potential of natural antimicrobials to control fungal growth and OTA production and the investigation of alternative ways of their application, e.g., via edible coatings. Fresh fruits were cut: i) in halves or ii) across in round slices of ca. 1 cm thickness. Wounds were introduced into the skin and the center of the slice (5 mm deep; 4 mm diameter) and inoculated with a range of 2.0–7.5 × 103spores per wound of Aspergillus carbonarius. Following inoculation, samples were coated with Na – alginate supplemented with 0.3 (0.3% ECC) and 0.9% v/v (0.9% ECC) cinnamon EΟ. Inoculated samples without edible coating and EO (C) or with edible coating and without EO (EC) were used as negative or positive controls, respectively. All samples were stored under aerobic conditions at 15, 20, and 25 °C. Fungal growth was estimated by colony diameter measurements (n = 30), while OTA production was determined by HPLC (n = 4). Antimicrobial treatment with 0.9% EO was more effective on fungal growth when the inoculation took place on slices than in wounded skin (p