The effect of UV‐C in combination with H₂O₂ treatments on microbial response and quality parameters of fresh cut pear discs

Abstract

The response of Escherichia coli ATCC 11229, Listeria innocua ATCC 33090 and Zygosaccharomyces bailii NRRL 7256 in fresh-cut pear to simultaneous and serial combined treatments involving H 2 O 2 immersion (3% w ⁄ v; pH 3.0; 25°C; 2.0 or 5.0 min) and UV-C exposure (7.5 min; 3.7 kJ m )2 ) was investigated. For selected treatments, native flora, sensory and colour changes were also evaluated. E. coli and L. innocua were more sensitive than Z. bailii. Serial H 2 O 2 ⁄ UV-C treatments were more effective than the simultaneous arrangement. The single effect of UV-C was enhanced by the combination with 5 min H 2 O 2 , hence avoiding the recovery of the surviving population. The combined treatment kept optimal microbial stability and exhibited more luminosity than the single UV-C treatment. Texture profile analysis conducted using a trained panel showed that H 2 O 2 ⁄ UV-C processed pear discs were perceived with significantly less hardness and fracturability but as juicy as untreated discs. Consumers found them pleasant.

Effect of UV-C radiation on bioactive compounds of pineapple (Ananas comosusL. Merr.) by-products

“…The ultra‐violet radiation at a wavelength of 190–280 nm (UV‐C) is one of the main sustainable sanitation techniques of fruits, since it is a non‐chemical treatment and can be used as an alternative to the conventional sanitation technique (chlorine) of fruits and vegetables . The use of UV‐C radiation is an environment friendly technique, is relatively inexpensive, easy to use and reduces most types of microorganisms . Beyond the sanitising effect, UV‐C radiation also induces stress in the plant which can promote the biosynthesis of compounds, namely bioactives such as carotenoids and vitamin C .…”

“…7 The use of UV-C radiation is an environment friendly technique, is relatively inexpensive, easy to use and reduces most types of microorganisms. 8 Beyond the sanitising effect, UV-C radiation also induces stress in the plant which can promote the biosynthesis of compounds, namely bioactives such as carotenoids and vitamin C. 9,10 The wavelength of 254 nm is often applied in the disinfection of fruit and vegetable surfaces, food packaging surfaces and liquid food products, like water and juices. 11 UV-C radiation contributes to the safety and nutritional quality of fruits and is currently seen as a promising sanitising treatment of whole and fresh-cut fruits, and vegetable surfaces.…”

UV‐C irradiation delays browning of fresh‐cut “Fuji” apples

“…Consequently, high PPO activity, excessive amounts of ROS, membrane damages, and low capacities of the antioxidant system induced surface browning of fresh-cut fruits and vegetables. UV-C is a safe sterilization technique that has been applied for the surface sterilization of various foods (Schenk et al, 2012). Appropriate doses of UV-C radiation can also effectively delay the surface browning of many fresh-cut fruits and vegetables during storage.…”

Effect of a continuous flow-through pulsed light system combined with ultrasound on microbial survivability, color and sensory shelf life of apple juice

“…Combining emerging technologies with conventional preserving ones or with other novel techniques to interfere with the homeostatic mechanisms of microorganisms has been successfully explored in the last years (Guerrero, López-Malo, & Alzamora, 2001;Guerrero, Tognon, & Alzamora, 2005;Ferrante, Guerrero, & Alzamora, 2007;Ferrario, Alzamora, & Guerrero, 2015;Lado & Yousef, 2002;Raso & Barbosa-Cánovas, 2003;Ross et al, 2003;Schenk, GarcíaLoredo, Raffellini, Alzamora, & Guerrero, 2012). If PL is combined with other preservation techniques which sensitize the organism structure to the action of light, microbial disruption, and then inactivation will be probably enhanced (Guerrero et al, 2014).…”