Overall quality properties in pressurized kiwi purée: Microbial, physicochemical, nutritive and sensory tests during refrigerated storage Ana Fernández-Sestelo a , Rut Sendra de Saá b , Concepción Pérez-Lamela b, ⁎, Ana Torrado-Agrasar b , María L. Rúa b , Lorenzo Pastrana-Castro b a School of Food Engineering, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile b Analytical Chemistry and Food Dept. Faculty of Sciences, University of Vigo, Campus of Ourense, E-32004, Spain abstract article info Article history: Received 8 January 2013 Accepted 28 June 2013 Available online xxxx Editor Proof Receive Date 15 July 2013 Keywords: Kiwi purée High pressure processing Physicochemical parameters Ascorbic acid Sensory analysis Overall quality Microbial inactivation A suitable option for exploiting kiwifruit is to develop a processed product. High pressure treatment (HPT) was applied to kiwi purée and chill-stored for two months. Measurements during storage were: °Brix, pH, color, vi- tamin C, citric and malic acids, glucose, fructose, sucrose, microbial levels and sensory tests. HPT reduced the ini- tial microbial load by 4 log; pH and °Brix were constant throughout storage and unaffected by pressurization. Just after the treatment, sugars and organic acids in the pressurized samples decreased by around 40 and 50%, and the color parameter a* increased by 50%. However, the levels remained almost constant and were similar in the unprocessed samples after five storage days. Similarly, the sensory assays showed significant differences be- tween the treated and untreated kiwi purées during the initial storage days, but after one storage week the dif- ferences decreased. HPT appears to be a good alternative for processing kiwi purée. Industrial relevance: Pasteurization of fruit purées with a high pressure treatment (HPT) has received consider- able attention during recent years and will become a proper industrial application in the future for exploiting kiwi surplus production. The overall quality data obtained in this work demonstrate that high pressure process- ing followed by chilled storage can extend the shelf-life of kiwi purée while maintaining its overall quality. Sensory measurements made by panelists and consumers are an important tool for deciding on the effective- ness of pressurization for certain processed fruit product. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction Kiwifruit has become increasingly important over recent decades, and indeed, a biannual international conference dealing only with ki- wifruit has been held since 1990, organized by the International Soci- ety for Horticultural Science (Acta Horticulturae, 2012). In several western countries it is considered an exotic fruit, and is greatly appre- ciated by customers for its health benefits related to its antioxidant and vitamin contents (Nishiyama, 2007). Moreover, kiwi crops have been grown in recent years in countries like Chile, Portugal, Spain and Italy. Consequently, an increase in fruit processing is expected to reduce losses due to fruit that is rejected by quality standards for the fresh market (about 10%) as well as surplus fruit production, which is stored in cooling chambers, that fails to sell (about 50%). Moreover, one of the major growth sectors in the food retail in- dustry is fresh and minimally processed fruits and vegetables (Lin & Zhao, 2007). Consumers demand minimally processed food products with similar or equivalent quality properties to the natural and fresh products, in compliance with food safety requirements (Houska et al., 2006). However, the color, firmness, and flavor of kiwi products processed with standard processing technologies (modified atmosphere packag- ing or thermal treatments, among others) are greatly reduced compared to fresh fruit (Stanley, Wegrzyn, & Saleh, 2007). Therefore, it would be interesting to develop new high-quality processed products in order to avoid organic waste and considerable economic loss for producers. High pressure treatment is a processing technology that was de- veloped at the end of the eighties for food applications (Yuste, Capellas, Pla, Fung, & Mor-Mur, 2001). This technology offers numer- ous opportunities for developing new foods with an extended shelf-life, high nutritional value and excellent organoleptic character- istics (Fonberg-Broczek et al., 2005). Some of the negative effects caused by heat treatments are that the flavor is modified and the nutrients degraded (Tewari, 2007). Un- like thermal processing and other preservation technologies, the ef- fects of HPT are uniform and nearly instantaneous throughout the food (Rastogi, Raghavarao, Balasubramaniam, Niranjan, & Knorr, 2007). Nevertheless, the advantages of HPT include that microbial safe foods and substantially equivalent products can be obtained (Mañas & Pagán, 2005). High Pressure Technologies have been widely applied to vegetable products (Oey, Lille, Van Loey, & Hendrickx, 2008a; Sánchez-Moreno, De Ancos, Plaza, Elez-Martinez, & Cano, 2009; Wendakoon, Matsuo, Innovative Food Science and Emerging Technologies xxx (2013) xxx–xxx ⁎ Corresponding author. Tel.: +34 988387091; fax: +34 988387001. E-mail address: conchipl@uvigo.es (C. Pérez-Lamela). INNFOO-01030; No of Pages 9 1466-8564/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ifset.2013.06.009 Contents lists available at SciVerse ScienceDirect Innovative Food Science and Emerging Technologies journal homepage: www.elsevier.com/locate/ifset Please cite this article as: Fernández-Sestelo, A., et al., Overall quality properties in pressurized kiwi purée: Microbial, physicochemical, nutritive and sensory tests during refrigerated..., Innovative Food Science and Emerging Technologies (2013), http://dx.doi.org/10.1016/j.ifset.2013.06.009