Conventional and Alternative Methods for Tomato Peeling

A pilot scale electrical infrared dry-peeling system for tomatoes: Design and performance evaluation

“…Small energy and carbon footprints, high water-use efficiency, wastewater management, and minimal chemical contamination have become critical factors in decision-making in terms of choices of food production and processing systems (Roy et al, 2009). In the fruit and vegetable industry, many unit operations such as peeling, blanching, and pasteurisation are energy-and water-intensive and result in huge amounts of wastewater with high salinity and organic loads (Das & Barringer, 2005;Milczarek & McCarthy, 2011;Pan, Li, Bingol, McHugh, & Atungulu, 2009;Rock, Yang, Goodrich-Schneider, & Feng, 2011;Setty, Vijayalakshimi, & Devi, 1993). The conventional peeling process is carried out using hot lye solution or pressurised steam.…”

“…The conventional peeling process is carried out using hot lye solution or pressurised steam. These peeling methods have been developed and optimised since the 1940s and have gained widespread application among fruit and vegetable processors in the United States (Masanet, Worrel, Graus, & Galitsky, 2007;Matthews & Bryan, 1969;Rock et al, 2011). But, in recent years, minimising water and chemical usage as well as the costs associated with disposal of peeling effluents have become important goals for the tomato industry.…”

“…All these findings demonstrated the promising potential of IR dry-peeling as a sustainable technology for the peeling of tomato and other vegetables. Over the past decade, much effort has been dedicated to developing different alternative peeling methods such as enzymatic peeling, ultrasonic peeling, and peeling using ohmic heat (Baker & Wicker, 1996;Dupleix, 2013;Emadi, 2005;Rock et al, 2011;Toker & Bayndrl, 2003;Wang, Li, Sun, Li, & Pan, 2014;Wongsa-Ngasri, 2004). Although attractive and environmentally friendly peeling methods have been increasingly investigated, successful commercialisation of any of the emerging technologies has not yet been fulfilled.…”

Characterization of the Red Layer and Pericarp of Processing Tomato using Magnetic Resonance Imaging

“…The pericarp of tomato fruit is comprised of the skin, exocarp, and the peripheral pericarp (Rock and others 2012). The exocarp includes the cell layers located underneath the skin of the tomato pericarp.…”

“…The peripheral pericarp is the inner portion of the pericarp under the exocarp. Because the exocarp is more richly colored than the other parts of the pericarp, it is also known as “red layer” (Garcia and Barrett 2006; Rock and others 2012). Vascular bundles, large white‐appearing regions in the middle of pericarp, separate the pericarp into regions with different optical properties and cell size (Devaux and others 2008).…”