Evaluation Of Olive Oil Research Articles

Evaluation of Brazilian Monovarietal Extra Virgin Olive Oils Using Digital Images and Independent Component Analysis

Digital images associated with chemometric tools, in a non-destructive approach, have been applied for the evaluation of the Brazilian monovarietal extra virgin olive oil. Independent component analysis (ICA) was employed in the image data evaluation of olive oils produced from distinctive olive varieties, and it was successful in highlighting the natural grouping among the samples based on the color histograms (red, green and blue (RGB) channels). The study’s proposal indicates the ability of accurate separation of the twenty-four samples considering their color. To conclude and support the hypothesis, principal component analysis (PCA) was applied in the visible spectra of the Brazilian monovarietal extra virgin olive oil, to observe the similarities between the samples, and the results are in agreement with those obtained by image analysis coupled with ICA. This method demonstrates the possibility for the characterization of olive oils respecting the principles of Green Chemistry.

Evaluation of olive oils from the Mediterranean region by UV–Vis spectroscopy and Independent Component Analysis

Extra-virgin olive oil (EVOO) from Mediterranean were analyzed by Ultraviolet–Visible (UV–Vis) spectroscopy and Independent Component Analysis (ICA). The use of ICA resolution provided information over dienes (primary oxidation compound), polyphenolic compounds, tocopherol, carotenoids and chlorophylls when EVOO was evaluated by UV–Vis spectroscopy. Based on these data, ICA could be used to determine the contribution of chemical compounds to the composition of EVOO produced in different regions from Mediterranean. The results suggest that the combination of UV–Vis measurements and ICA makes possible the EVOO evaluation, and can contribute to suggesting that a foodstuff comes from an alleged origin. The proposed methodology is a low cost, fast and sample preparation free methodology to highlights the EVOO characteristics produced in the Mediterranean region.

Sensory Evaluation of Olive Oils and Activities of Kagawa Prefecture

Sensory Evaluation of Olive Oils and Activities of Kagawa Prefecture

Monovarietal extra-virgin olive oil classification: a fusion of human sensory attributes and an electronic tongue

Olive oil quality grading is traditionally assessed by human sensory evaluation of positive and negative attributes (olfactory, gustatory, and final olfactory–gustatory sensations). However, it is not guaranteed that trained panelist can correctly classify monovarietal extra-virgin olive oils according to olive cultivar. In this work, the potential application of human (sensory panelists) and artificial (electronic tongue) sensory evaluation of olive oils was studied aiming to discriminate eight single-cultivar extra-virgin olive oils. Linear discriminant, partial least square discriminant, and sparse partial least square discriminant analyses were evaluated. The best predictive classification was obtained using linear discriminant analysis with simulated annealing selection algorithm. A low-level data fusion approach (18 electronic tongue signals and nine sensory attributes) enabled 100 % leave-one-out cross-validation correct classification, improving the discrimination capability of the individual use of sensor profiles or sensory attributes (70 and 57 % leave-one-out correct classifications, respectively). So, human sensory evaluation and electronic tongue analysis may be used as complementary tools allowing successful monovarietal olive oil discrimination.

Evaluation of Olive Oil as a Separating Medium and Its Effect on Some Physical Properties of Processed Acrylic Resin Denture Base : A Comparative Study : Part One

Evaluation of Olive Oil as a Separating Medium and Its Effect on Some Physical Properties of Processed Acrylic Resin Denture Base : A Comparative Study : Part One

THE INFLUENCE OF LOCAL CANNING PROCESS AND STORAGE ON PELAGIC FISH FROM TUNISIA: FATTY ACID PROFILES AND QUALITY INDICATORS

The present study was designed to assess the effect of local canning process and storage time (up to 6 months) on tuna and sardine canned in olive oil and tomato sauce, respectively. The canning process affected tuna (P < 0.05) but not sardine lipid levels. Canned tuna and sardine absorbed coating oil during sterilization, inducing a higher oleic (C18:1 ω9) and linoleic (C18:2 ω6) acid content. Independent of fish species, the eicosapentaenoic (C20:5 ω3) and docosahexaenoic (C22:6 ω3) acid concentrations ranged from 2.96–6.24% and from 5.16–40.26%, respectively. The peroxide value and thiobarbituric acid index increased significantly in tuna but not in sardine flesh following the cooking step. The histamine levels increased significantly (P < 0.05) during storage but remained lower than the threshold limits. Although tuna and sardine flesh were slightly affected by the canning process, they remained good sources of ω3 and ω6 fatty acids. PRACTICAL APPLICATIONS In the present study, we investigate the changes of the lipid fraction quality (fatty acids composition, peroxide value and thiobarbituric acid index) and histamine during processing and storage of two different fish species (tuna and sardine) processed during the same period. This would allow for the assessment of the different canning process steps (cooking and sterilization) and storage on fish meat, especially on its lipid quality. To our knowledge, such information is rather scarce. An evaluation of olive oil and tomato sauce effects on the enrichment of the nutritional oil quality of the tuna and sardine, respectively, and the stability of fish lipids oxidation were equally conducted. Finally, these data may supply some valuable information for other scientists working in the field of human nutrition.

Qualitative evaluation of olive oils from new olive selections and effects of genotype and environment on oil quality

In the dynamically changing olive oil industry, new cultivars with greateradaptability to modern cul - tivation techniques and with high quality oils are needed. In this paper, oil quality, in terms of fatty acid compo - sition and content in phenolic compounds, was analysed for many new genotypes previously selected in a bree- ding program and cultivated in three different locations of central and southern Italy. Data on some cultivars commonly grown in each area were included for comparison. The availability of data from many genotypes cul - tivated in all three locations allowed quantitative analyses of the genetic and environmental effects on the oil qua - lity traits studied. The acidic composition varied greatly both with genotype and with environment and so did the concentration in phenols, though the effect of genotype on phenols was not significant (P=0.09). The fatty acid composition, particularly the oleic/(palmitic+linoleic) ratio, appeared predominantly under genetic control, with a broad sense heritability of 0.58 while the environmental effect explained 0.31 of the total variance. The oil con - tent in phenolic compounds, instead, had lower heritability (0.29) and was more affected by the environment, which explained 0.50 of the total variance. Few genotypes were selected as the best for each location, but none performed best in all locations. This suggests that, in olive, the highest oil quality is difficult to achieve with a sin - gle genotype in different environments, due to a strong or even predominant effect of the environment on some quality traits. More likely, combinations of genotypes and territories can produce oils with high and typical qua - lity. In this paper, we provide information on potential new genotypes with promising performances in different Italian regions. Further testing of oil quality, together with agronomic performance, is necessary prior to any release of new cultivars.

Evaluation of olive oils through the fatty alcohols, the sterols and their esters by coupled LC‐GC

The analysis of the fatty alcohols, the wax esters, the free and the esterified sterols, as well as that of minor components provides a wealth of information about the quality of an oil or fat, its pretreatment and admixture with other oils. Some results obtained by an easy, nearly fully‐automated method are shown for olive oils. More specific information is obtained than by the previous saponification methods.