An integrated approach for flavour quality evaluation in muskmelon (Cucumis melo L. reticulatus group) during ripening Simona Vallone a , Hanne Sivertsen b , Gordon E. Anthon b , Diane M. Barrett b , Elizabeth J. Mitcham a , Susan E. Ebeler c , Florence Zakharov a,⇑ a Department of Plant Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA b Department of Food Science and Technology, University of California, One Shields Avenue, Davis, CA 95616, USA c Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA article info Article history: Received 6 July 2012 Received in revised form 20 December 2012 Accepted 28 December 2012 Available online 7 January 2013 Keywords: Melon maturity Ripening Aroma Flavour Volatiles Sensory descriptive analysis zNose Headspace sorptive extraction abstract Numerous and diverse physiological changes occur during fruit ripening and maturity at harvest is one of the key factors influencing the flavour quality of fruits. The effect of ripening on chemical composition, physical parameters and sensory perception of three muskmelon (Cucumis melo L. reticulatus group) cul- tivars was evaluated. Significant correlations emerging from this extensive data set are discussed in the context of identifying potential targets for melon sensory quality improvement. A portable ultra-fast gas- chromatograph coupled with a surface acoustic wave sensor (UFGC–SAW) was also used to monitor aroma volatile concentrations during fruit ripening and evaluated for its ability to predict the sensory perception of melon flavour. UFGC–SAW analysis allowed the discrimination of melon maturity stage based on six measured peaks, whose abundance was positively correlated to maturity-specific sensory attributes. Our findings suggest that this technology shows promise for future applications in rapid fla- vour quality evaluation. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction Netted muskmelon (Cucumis melo L., reticulatus group), also commonly called cantaloupe, is an orange-fleshed, sweet and aro- matic melon that is highly popular in the United States, represent- ing a large share of the produce market. In 2010, the estimated net domestic use of muskmelon totaled over 2.6 billion pounds, and muskmelon ranked fourth in U.S. annual per capita consumption of fresh fruit after bananas, watermelons and apples (USDA-ERS, 2010). Consumer surveys assessing ‘‘overall preference’’ for several muskmelon cultivars highlighted that flavour, sweetness and tex- ture were important factors in determining consumer liking of melons (Lester, 2006). While these attributes are dictated by the specific cultivar, or genetic makeup, of the muskmelon, maturity at harvest has also been shown to have a large impact on the sugar content (related to sweetness), volatile content (related to flavour and aroma) and texture of melon fruit (Beaulieu & Grimm, 2001; Beaulieu, Ingram, Lea, & Bett-Garber, 2004; Beaulieu & Lancaster, 2007; Pratt, 1971). Harvesting firmer and early mature fruits is a commercial practice commonly adopted in order to maximise post-harvest life during handling, shipping and storage of climacteric fruits (Kader, 2008). However, this practice is detrimental for flavour quality be- cause it does not allow full development of the fruit aroma profile (Beaulieu, 2006; Beaulieu et al., 2004; Wyllie, Leach, & Wang, 1996). Typically, muskmelon fruit maturity in the field is determined by the extent of the development of an abscission layer (also called ‘‘slip’’ in the trade) between the vine and the fruit. In California, melons are generally harvested at 3 = 4 - to full-slip stage for local market distribution. However, genetic, environmental and agro- nomic factors often complicate maturity assessment by influencing fruit physiology and the development of this abscission zone, resulting in variable postharvest fruit quality. In addition, melons destined for long distance transport are typically harvested earlier, sometimes even before the clear development of an abscission zone. Due to the interactions of many parameters (e.g., sugar content, aroma profile, colour, texture) in determining fruit sensory charac- teristics, measuring a single composition parameter such as sugar content is seldom sufficient to reflect an objective assessment of overall fruit flavour quality. From an applicative perspective, a comprehensive assessment of flavour quality is often unfeasible due to the requirement of expensive analytical instrumentation, highly trained personnel and time- and labour-consuming proce- 0308-8146/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.foodchem.2012.12.042 ⇑ Corresponding author. Tel.: +1 530 752 4374; fax: +1 530 752 8502. E-mail address: fnegre@ucdavis.edu (F. Zakharov). Food Chemistry 139 (2013) 171–183 Contents lists available at SciVerse ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem