Original scientific paper

Influence of harvest time on the composition and quality of Rosinjola cultivar virgin olive oils

Karolina Brkić Bubola orcid.org/0000-0002-7132-9220 ; Institute of Agriculture and Tourism, K. Huguesa 8, 52440 Poreč, Croatia
Olivera Koprivnjak ; University of Rijeka, School of Medicine, Braće Branchetta 20, 51000 Rijeka, Croatia
Barbara Sladonja ; Institute of Agriculture and Tourism, K. Huguesa 8, 52440 Poreč, Croatia
Dubravka Škevin ; University of Zagreb, Faculty of Food Technology and Biotechnology, Pierottijeva 6, 10000, Zagreb, Croatia
Ivana Belobrajić ; Ital-Ice Ltd., M. Vlašića 47, 52440 Poreč, Croatia

Abstract

The aim of this investigation was to determine the influence of Rosinjola cultivar fruits harvest time on oil content in olive pastes and on composition and quality of obtained oils. In the late harvest time the higher value of oil in the dry matter of olive paste was determined than in the early harvest time, but the late harvest negatively affected oil quality parameters. The proportion of oleic acid decreased slightly in the late harvest time and linoleic acid increased. The ratio of oleic/linoleic acid, total phenols and ortho-diphenols, as well as bitterness index and antioxidant capacity decreased in the oil obtained from black fruit. Late harvest time influenced the decrease in chlorophyll and carotenoid content and color parameter values (a*, b* and C) in obtained oils, but lightness (L*) increased. The concentration of volatiles responsible for positive odour of Rosinjola oils decreased, except for aldehydes which increased slightly. Sensory score of oil obtained from the late harvest time decreased, as well as intensities of sensory characteristics olive fruity, apple, green grass, bitter and pungent, while the intensities of characteristics sweet and ripe fruits increased. Oils obtained in the early harvest time were described as harmonious and astringent with pronounced green odour notes, and oils obtained in the late harvest time as overripe and without freshness. The obtained results are important for optimal harvest time determination and understanding the potential of Rosinjola cultivar for production of high quality virgin olive oil with targeted and specific characteristics.

Keywords

virgin olive oil; harvest time; quality characteristics; sensory profile; chemical composition

Hrčak ID:

84715

URI

https://hrcak.srce.hr/84715

Publication date:

19.7.2012.

Article data in other languages: croatian

Visits: 3.870 *