Improving microbiological and physicochemical properties of fresh-cut apples using carvacrol emulsions

The cut or sliced form of apples are more prone to chemical deterioration and microbial growth. In this work, quality changes (physicochemical properties, sensory quality, and microbial growth) of fresh-cut apples stored at 4 °C for 15 days were studied after immersion treatment (water, biopolymer complex; free carvacrol, and carvacrol emulsion). Whey protein isolate/high methoxyl pectin-based carvacrol emulsions effectively delayed the browning process and reduced variation in chemical quality compared to other groups. Apples treated with carvacrol emulsions were more favored by panelists at the middle- and late-stages of storage. Additionally, the presence of carvacrol emulsions improved microbial safety, as demonstrated by the number of viable bacteria (<6 log CFU/g) and yeast and mold (<5 log CFU/g) after 15 d of storage. 16 S rRNA Gene Sequencing was used to identify the bacterial species responsible for the spoilage of fresh-cut apples. These results show that carvacrol emulsions are a potential preservation alternative for fresh-cut apples.