The effect of UV-C and electrolyzed water on yeasts on fresh-cut apple at 4 °C. (October 2020)

• Record Type: Journal Article
• Authors: Graça, Ana; Santo, David; Pires-Cabral, Paula; Quintas, Célia
• Is Part Of: Journal of food engineering. Volume 282(2020)
• Publication Date: 2020-10
• Subjects: Minimally processed apple -- Yeasts -- UV-C -- Acidic electrolyzed water -- Neutral electrolyzed water -- Sodium hypochlorite; Food industry and trade -- Periodicals; Food -- Analysis -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Analyse -- Périodiques; Aliments -- Recherche -- Périodiques; 664.005
• DOI: 10.1016/j.jfoodeng.2020.110034
• Languages: English
• ISSNs: 0260-8774

Abstract

Abstract: The growth of a yeast mixture, Candida sake, Hanseniaspora uvarum, Pichia fermentans, Metschnikowia pulcherrima, on fresh-cut apple (Royal gala), at 4 °C, was studied, as well as the reduction of yeasts using Ultraviolet-C (UV–C), acidic (AEW) and neutral (NEW) electrolyzed waters, and sodium hypochlorite (SH). Apple portions were contaminated then disinfected with UV-C (2.5–10 kJ/m 2 ), AEW, NEW and SH (100 ppm). During 9 days at 4 °C, yeasts growth rate was 0.34 day −1 and the stationary phase occurred after 6 days (7.42 LogCFU/g). The initial microbial reduction and the half-life time values, using the inverse hyperbola model, ranged from 1.72 to 1.81 LogCFU/g and 6.52–11.70 day (UV–C), or 0.91 to 1.96 LogCFU/g and 0.68–4.38 day (chemical treatments), where SH was the least efficient (0.92 LogCFU/g and 2.96 day). The most effective treatment was UV-C (7.5 and 10 kJ/m 2 ). The yeasts psychrotrophic profile highlights the importance of avoiding contamination/cross-contaminations in all processing. Highlights: The growth of a mixture of yeasts species was studied on fresh-cut apple at 4 °C. The effect of UV-C and electrolyzed waters on the reduction of yeasts was evaluated. The yeasts increased their population at 4 °C at a specific growth rate of 0.34 day −1 . All treatments showed higher reduction values of yeasts than sodium hypochlorite. The UV-C method resulted in higher yeast reductions after nine days of storage.