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Table Olives (table + olive)

Distribution by Scientific Domains

Life Sciences	60%

Selected Abstracts

Comparative analysis of triacylglycerols from Olea europaea L. fruits using HPLC and MALDI-TOFMS

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2010
Faouzi Sakouhi
Abstract MALDI-TOFMS and HPLC are two analytical methods that were used to characterize triacylglycerols (TAG) of the Meski, Sayali, and Picholine Tunisian olive varieties. The HPLC chromatograms of the oils showed the presence of 15 TAG species, among which triolein (OOO) was the most abundant (21,48%). In the Sayali cultivar, OOO was the predominant TAG species followed by POO and LOO. However, the minor TAG molecules were represented by LnLO and LnLP. MALDI mass spectra produced sodiated ([M,+,Na]+) and potassiated ([M,+,K]+) TAG molecules; only the major TAG were potassiated [OOO,+,K] ([OOO,+,K]+, [POO,+,K]+, and [LOO,+,K]+). In contrast to the HPLC chromatograms, the MALDI mass spectra showed 13 peaks of TAG. The major peak was detected at m/z,907, which corresponds to OOO with an Na+ adduct. The results from both HPLC and MALDI techniques predict the fatty acid composition and their percentages for each olive variety. Practical applications: TAG are the main components in vegetable oils. These biomolecules determine the physical, chemical, and nutritional properties of the oils. The nutritional benefits of TAG are related to DAG (moderate plasma lipid level) and esterified FA, which are intermediate biosynthetic molecules of TAG. TAG analysis is necessary to discriminate between oils of different origin, since some oils have similar FA profiles. Olive products, oils, and table olives, are the main diet sources of TAG in the Mediterranean countries. In this work, chromatographic and spectrometric methods were used for TAG analysis and characterization of Tunisian olive varieties. [source]

Study of the anti-lactic acid bacteria compounds in table olives

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 7 2009
Eduardo Medina
Summary The analysis and formation of anti-lactic acid bacteria compounds in olive brines was performed for the main worldwide olive varieties intended for table olives. The results demonstrated that the growth of lactic acid bacteria in the brines of olives non-treated with NaOH is, in some way, variety dependant. Likewise, the most active antimicrobial compound, the dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol, was not detected in fresh fruits but it was formed during brining from the hydrolysis of oleuropein and this reaction was enzymatically catalysed. Thus, the inactivation of the enzyme by heating the olives produced (i) an accumulation of oleuropein in olives and brines, (ii) the inhibition of the formation of antimicrobials and (iii) the growth of Lactobacillus pentosus in olive brines. These results provide tools for a full understanding of the growth or inhibition of lactic acid bacteria during fermentation of table olives. [source]

Modelling the combined effect of temperature, pH and aw on the growth rate of Monascus ruber, a heat-resistant fungus isolated from green table olives

JOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2003
E.Z. Panagou
Abstract Aims: Growth modes predicting the effect of pH (3·5,5·0), NaCl (2,10%), i.e. aw (0·937,0·970) and temperature (20,40°C) on the colony growth rate of Monascus ruber, a fungus isolated from thermally-processed olives of the Conservolea variety, were developed on a solid culture medium. Methods and Results: Fungal growth was measured as colony diameter on a daily basis. The primary predictive model of Baranyi was used to fit the growth data and estimate the maximum specific growth rates. Combined secondary predictive models were developed and comparatively evaluated based on polynomial, Davey, gamma concept and Rosso equations. The data-set was fitted successfully in all models. However, models with biological interpretable parameters (gamma concept and Rosso equation) were highly rated compared with the polynomial equation and Davey model and gave realistic cardinal pHs, temperatures and aw. Conclusions: The combined effect of temperature, pH and aw on growth responses of M. ruber could be satisfactorily predicted under the current experimental conditions, and the models examined could serve as tools for this purpose. Significance and Impact of the Study: The results can be successfully employed by the industry to predict the extent of fungal growth on table olives. [source]