title: Effects of wax coatings and postharvest storage on sensory quality and aroma volatile composition of 'Mor' mandarins.
abstract: BACKGROUND
  Mandarins suffer from accumulation of off-flavours after harvest. In this study the sensory quality and aroma profile composition of homogenised segments of untreated (control) and wax-coated 'Mor' mandarins after 7 days at 20 degrees C or 3 or 6 weeks of cold storage at 5 degrees C were examined.
  
  
  RESULTS
  Fruit taste score decreased during storage and following wax coating, and this was attributed to decreases in sourness and mandarin flavour and accumulation of off-flavours. Aroma profiling identified 31 volatiles that decreased by at least 50% during storage and after waxing and thus may be involved in the observed flavour loss. In contrast, 13 volatiles, mostly belonging to ethanol fermentation and fatty acid and amino acid catabolism pathways, significantly increased at least twofold and probably contributed to off-flavour enhancement.
  
  
  CONCLUSIONS
  The results showed that after harvest there was a progressive decrease in sensory quality of 'Mor' mandarins. It is proposed that observed decreases in contents of sesqui- and monoterpenes and short-chain oxygenated fatty acids may contribute to the decrease in mandarin flavour, whereas increases in the contents of ethanol fermentation metabolites and derivates of fatty acid and amino acid catabolism are most likely involved in causing the enhanced sensation of off-flavours.
authors.affiliation: Department of Postharvest Science of Fresh Produce, ARO, The Volcani Center, PO Box 6, Bet Dagan 50250, Israel.
authors.forename: Zipora
authors.initials: Z
authors.lastname: Tietel
authors.forename: Einat
authors.initials: E
authors.lastname: Bar
authors.forename: Efraim
authors.initials: E
authors.lastname: Lewinsohn
authors.forename: Ester
authors.initials: E
authors.lastname: Feldmesser
authors.forename: Elazar
authors.initials: E
authors.lastname: Fallik
authors.forename: Ron
authors.initials: R
authors.lastname: Porat
mesh_terms: D000328:Adult; D002957:Citrus / Q000737:chemistry*; D005260:Female; D005511:Food Handling / Q000379:methods*; D005638:Fruit / Q000737:chemistry* / Q000592:standards; D006801:Humans; D008297:Male; D053858:Metabolic Networks and Pathways; D008875:Middle Aged; D009812:Odorants; D013649:Taste; D055549:Volatile Organic Compounds / Q000032:analysis*; D014835:Volatilization; D014885:Waxes
chemical_list: D055549:Volatile Organic Compounds; D014885:Waxes