How 'ground-picked' olive fruits affect virgin olive oil ethanol content, ethyl esters and quality

J Sci Food Agric. 2016 Aug;96(11):3801-6. doi: 10.1002/jsfa.7573. Epub 2016 Feb 5.

Abstract

Background: Olives dropped on the ground naturally sometimes are not separated from those fresh and healthy collected from the tree for harvest and processing. In this work we compared the quality, ethanol content and bioactive components of virgin olive oils from ground-picked olives, tree-picked fruits and their mixture.

Results: Ground-picked olives produced 'Lampante' virgin olive oils; these are of a lower quality category, because of important alterations in chemical and sensory characteristics. Ethyl esters showed the highest values, although under the regulated limit. The mixture of ground and tree-picked olives gave oils classified as 'virgin' because of sensory defects, although the quality parameters did not exceed the limits for the 'extra' category. Ethanol content showed a significant increase in the oils from ground- picked olives and their mixture with respect to those from tree-picked fruits. Furthermore, bioactive compounds showed a significant decrease as fruit quality was poorer.

Conclusion: Ground-picked olives must be harvested and processed separately since they produce low-quality virgin olive oils with sensory defects and lower concentrations of bioactive compounds. The higher acidity and ethanol concentration observed in oils from ground-picked fruits or their mixture may help ethyl ester synthesis during storage. © 2015 Society of Chemical Industry.

Keywords: bioactive compounds; ethanol; ethyl esters; ground-picked olives; quality; virgin olive oil.

Publication types

  • Comparative Study

MeSH terms

  • Centrifugation
  • Crop Production / methods*
  • Crops, Agricultural / chemistry*
  • Crops, Agricultural / growth & development
  • Crops, Agricultural / metabolism
  • Esters / analysis
  • Esters / metabolism
  • Ethanol / analysis*
  • Ethanol / metabolism
  • Food Handling
  • Food Inspection
  • Food Quality*
  • Fruit / chemistry*
  • Fruit / growth & development
  • Fruit / metabolism
  • Humans
  • Hydrogen-Ion Concentration
  • Olea / chemistry*
  • Olea / growth & development
  • Olea / metabolism
  • Olive Oil / chemistry*
  • Olive Oil / isolation & purification
  • Olive Oil / standards
  • Sensation
  • Spain

Substances

  • Esters
  • Olive Oil
  • Ethanol