Chemical and sensory characterization of Brazilian virgin olive oils

Food Res Int. 2019 Dec:126:108588. doi: 10.1016/j.foodres.2019.108588. Epub 2019 Jul 29.

Abstract

Brazil is an emerging virgin olive oil producer country whose oils have been scarcely studied till now and, in particular, no data are present in literature about their volatile profiles and organoleptic characteristics as well as the Pearson's correlations between chemical and sensory parameters. Hence, giving insights about these aspects was the aim of the current investigation. The volatile profiles showed the presence of the aldehydes responsible for the positive attribute of VOOs (i.e. trans-2-Hexenal and hexanal) although, in some cases, volatiles from anaerobic and aerobic fermentation were also detected. The panel test showed low values of fruity and pungent notes (mean values of 1.1 and 0.6, respectively) whereas the bitter taste was detected only in one sample, probably due to the low amount of total phenolic compounds (ranging from 40 to 280 mg kg-1). Accordingly to the volatiles analysis, slight defects of the oils were evidenced by the panelists. Tocopherols ranged from 123 to 222 mg kg-1; carotenoids from 10.69 to 26.18 mg kg-1, chlorophylls from 14.06 to 54.90 mg kg-1, antioxidant activity from 976 to 1790 μmol TE g-1, and fatty acid ethyl esters from 2.56 to 19.22 mg kg-1. Positive Pearson's correlations were highlighted between hydroxytyrosol derivatives and antioxidant activity (r = 0.9601, p < .0001), trans-2-hexenal and fruity median (r = 0.6526, p < .05), acetic acid and vinegary defect (r = 0.7854, p < .0001), and fatty acid ethyl esters and vinegary defect (r = 0.8418, p < .0001). Our findings give first insights about sensory characteristics of Brazilian virgin olive oils and their association with chemical quality parameters. Finally, based on the obtained data, an improvement of preliminary operations (harvesting, storage) of the extraction process is recommended.

Keywords: Antioxidants; Brazilian VOO; Ethyl esters; Panel test; Phenolic compounds; VOO quality; Volatile compounds.

MeSH terms

  • Aldehydes / analysis
  • Antioxidants / analysis
  • Brazil
  • Carotenoids / analysis
  • Fatty Acids / analysis
  • Food Analysis*
  • Olea / chemistry
  • Olive Oil / chemistry*
  • Phenols / analysis
  • Principal Component Analysis
  • Sensation
  • Taste*
  • Tocopherols / analysis
  • Volatile Organic Compounds / analysis

Substances

  • Aldehydes
  • Antioxidants
  • Fatty Acids
  • Olive Oil
  • Phenols
  • Volatile Organic Compounds
  • Carotenoids
  • 2-hexenal
  • n-hexanal
  • Tocopherols