Comparison of some chemical parameters of a naturally debittered olive (Olea europaea L.) type with regular olive varieties

Abstract

a b s t r a c tSome olives grown in Karaburun peninsula in the west part of Turkey and mostly coming from Erkence variety lose their bitterness while still on the tree and are called Hurma among locals. This olive type does not require further processing to remove the bitter compounds. In this study, sugar, organic acid and fatty acid profiles of Hurma, Erkence (not naturally debittered) and Gemlik (commonly consumed as table olive) olives were determined throughout 8 weeks of maturation period for two consecutive harvest seasons, and the results were analysed by principal component analysis (PCA). PCA of sugar and organic acid data revealed a differentiation in terms of harvest year but not on variety. Hurma olive is separated from others due to its fatty acid profile, and it has higher linoleic acid content compared to others. This might be an indication of increased desaturase enzyme activity for Hurma olives during natural debittering phase.

Argania spinosa var. mutica and var. apiculata: Variation of Fatty‐Acid Composition, Phenolic Content, and Antioxidant and α‐Amylase‐Inhibitory Activities among Varieties, Organs, and Development Stages

“…Within eachg roup,t he variation between samples occured according to the harvest period. As ar esult, it can be concluded that the fatty-acid composition providedalevel of differentiation with respect to arganv arieties,f ruit parts,and harvesting time.The distinction between the two varieties based on the fattyacid profiles was in agreement with phytochemical and taxonomic correlations reported for varieties of several species [ 40] [43]. However,s ampleso fm ore argan trees of both varieties from different bioclimatic and geographic zones,such as Tunisia, Algeria, and Morocco,should be collected, to draw adefinite conclusion on this matter.…”

An explanation for the natural de-bittering of Hurma olives during ripening on the tree

“…A trend to higher sugar content in Erkence olives harvested from the southern area of the trees than the north was also detected although it was not always significant. Surprisingly, the content of glucose was much lower in Hurma than Erkence olives but this effect was not detected for the concentration of fructose and mannitol, and it was not observed in a previous study (Aktas et al, 2014b). It is wellknown that respiration is enhanced in freeze-injured and fungus infected fruits (Fuchs et al, 1975;Liu et al, 2005), and olives consume mannitol and fructose at a higher rate than glucose during their postharvest period (García et al, 1995).…”

“…These olives possess a higher linoleic acid content than Erkence, which might be an indication of increased desaturase enzyme activity during the natural debittering phase (Aktas et al, 2014b). In addition, it has been suggested that the fungus named Phoma oleae could be involved in the hydrolysis of oleuropein (Panagou, 2006), although it is not the prevalent microorganism on the surface of Hurma olives (Sozvilen and Baysal, 2016).…”

Antioxidant capacity, fatty acids profile, and descriptive sensory analysis of table olives as affected by deficit irrigation

“…5 Table olives are probably the most important fermented food in the Mediterranean countries and are very valuable because of their highly appreciated taste and rich nutritional composition leading to interesting health benefits. 6 Therefore, the daily consumption of table olives will contribute in an important way to the intake of healthy substances, such as phenolic compounds, which are highly recommended because of their antioxidant properties. 7 Although irrigation normally has a positive impact on olive production, it is also known that different water regimes can affect its nutritional, antioxidant and quality components.…”