Contents lists available at ScienceDirect Postharvest Biology and Technology journal homepage: www.elsevier.com/locate/postharvbio 1-MCP and storage conditions on the ripening and production of aromatic compounds in Conference and Alexander Lucas pears harvested at different maturity stages Marcos Vinícius Hendges a, ⁎ , Daniel Alexandre Neuwald b , Cristiano André Steffens a , Rajko Vidrih c , Emil Zlatić c , Cassandro Vidal Talamini do Amarante a a Department of Agronomy, State University of Santa Catarina, Lages, Brazil b Competence Center for Fruit Growing – Lake Constance and Physiology of Specialty, Crops University of Hohenheim, Ravensburg, Germany c Department of Food Science and Technology, Biotechnical Faculty, Ljubljana, Slovenia ARTICLE INFO Keywords: Pyrus communis Cultivar Ethylene Controlled atmosphere Volatile ABSTRACT The objective of this investigation was to evaluate the quality parameters and aroma profiles of Conference and Alexander Lucas pears after 7 months of storage. Fruits of both cultivars were harvested at two different maturity stages and stored under cold (CS) (20.9 kPa O 2 + < 0.04 kPa CO 2 ), controlled atmosphere (CA) (2 kPa O 2 + < 0.7 kPa CO 2 ) and ultra-low oxygen condition (ULO) (0.7 kPa O 2 + < 0.7 kPa CO 2 ). CS and CA storage also included treatment with 1-methylcyclopropene (1-MCP) at 300 nL L -1 . After seven months of storage at 0 ± 0.1 °C and 94 ± 2% RH plus seven days at 20 ± 2 °C and 60 ± 5% RH, fruits were evaluated for flesh firmness, peel color ('hue' angle = h°), soluble solids content (SSC), titratable acidity (TA), respiratory rate, ethylene production rate, and production of aromatic compounds. Fruits of both cultivars from the first maturity stage treated with 1-MCP did not develop a buttery texture or yellow color and produced significantly less alcohols and esters. A combination treatment (1-MCP + CA) most severely suppressed aroma development, particularly in the Conference cultivar. ULO storage also reduced yellowing, ethylene production and the de- velopment of aromatic compounds in both cultivars from the first maturity stage, but this reduction was less pronounced than that observed for 1-MCP treatments. The production of aromatic compounds was lower in fruits from ULO, regardless of their maturity stage. Fruits from the second harvest treated with 1-MCP had significantly more aromatic compounds than did those from the first harvest. In general, the CA condition has no effect on the ripening and production of aromatic compounds in both cultivars compared to CS. 1. Introduction The development of a buttery texture, yellowing of the peel, synthesis of aromatic compounds, and adequate sugar-acid content are important quality attributes in European pears (Kappel et al., 1995; Plocharski and Konopacka, 1999; Mitcham et al., 2003). Conference pears are among the most cultivated in Europe (Chiriboga et al., 2013b) and present juicy, crunchy flesh with sweet taste (Saquet, 2016). This cultivar is harvested from September and stored until February under cold and end of April in controlled atmosphere (Silbereisen et al., 2015). Alexander Lucas are cultivated mainly in Germany, Holland, Czech Republic and Poland with not to many evidence about post- harvest behavior. Although not very representative in Europe its pro- duction has increased in countries such as Holland and Poland (Groot et al., 2000; Wawrzyńczak et al., 2006). This cultivar is characterized by large fruits, yellow epidermis when completely mature and, in some cases with reddish spots. The flesh is juicy with sweet and fruity taste (Silbereisen et al., 2015). Different postharvest technologies, such as cold storage (CS) and controlled atmosphere (CA) storage conditions are used to maintain the fruit quality during and after storage of pears. CA storage delays ri- pening and maintains fruit quality (Moya-León et al., 2006), but it may cause a significant decrease in the production of aromatic compounds of Packham’s Triumph, Doyenne du Comice (Chervin et al., 2000; Lara et al., 2003), and especially under conditions of ultra-low oxygen (ULO) in Bartlett pears (Zlatić et al., 2016). However, this quality reduction may be overcome by harvesting the fruits at later maturity stages (cli- macteric phase) (Brackmann et al., 1993). https://doi.org/10.1016/j.postharvbio.2018.08.006 Received 19 February 2018; Received in revised form 12 June 2018; Accepted 8 August 2018 ⁎ Corresponding author. E-mail address: marcos_hendges@hotmail.com (M.V. Hendges). Postharvest Biology and Technology 146 (2018) 18–25 0925-5214/ © 2018 Elsevier B.V. All rights reserved. T