Table Olive Samples Research Articles

Determination of Bacterial Community Structure of Table Olive via Metagenomic Approach in Şarköy.

One of the most popular pickled foods created worldwide is table olives. The aim was to identify the bacterial microbiota of table olive samples collected from Şarköy, Tekirdağ-Türkiye using next generation sequencing and 16S metagenomic analysis. Samples were studied as non-pre-enriched (n : 10) and after pre-enrichment (n : 10) to compare the effects of the enrichment process on the bacterial diversity. In non-pre-enriched, the most common genus found was Sphingomonas, followed by Altererythrobacter and Lysobacter. The most common phylum found was Proteobacteria, followed by Bacteroidota and Actinobacteria. In pre-enriched, Bacillus was the most commonly detected genus, followed by Pantoea and Staphylococcus. The most frequently found phylum was Firmicutes, followed by Proteobacteria and Cyanobacteria. This study is the first study for Şarköy, which is the only table olive production place in the Tekirdağ region due to its microclimate feature. Further studies are needed in more table olive samples from different geographical areas to confirm and develop current findings.

Use of molecular methods for the identification of yeast species isolated from fermentations of table olives produced traditionally in Kahramanmaraş

In this study, yeast species involved in the naturally fermented green table olive produced in Southern Turkey were investigated. Table olive samples were prepared with regional olive cultivars and traditional methods were employed in the production. Yeasts were isolated from the brines of the samples at the late fermentation stage and identified at the species level by the DNA sequences of the D1/D2 domain of 26S rRNA genes. The D1/D2 domains were amplified by PCR, sequenced and compared to reference sequences deposited in the NCBI database. According to the results, isolated yeasts belonged to the Candida, Debaryomyces, and Rhodotorula genera and salt tolerant species were dominant as the salt content of the brines exceeded 11%. Among the determined species, Candida oleophila was the most dominant one and it was thought that isolated strains of Candida oleophila may be taken into consideration to be used as starter culture in table olive production.

Mask R-CNN for quality control of table olives

In this paper we propose an object detector based on deep learning for scanning samples of table olives. For the construction of the system we have used a Mask R-CNN neural network. This network is able to segment the image providing a mask for each of the olives in the sample from which we can obtain the calibre of the object. In addition, the system is able to measure the degree of ripeness of the olives classifying them as green, semi-ripe and ripe, and identifying those fruits that are defective due to disease or damage caused by the harvesting process. The proposed system achieves success rates of 99.8% in the detection of olive fruits in photograms, 93.5% in the classification of fruit by ripeness and close to 80% in the detection of defects.

Formation of gas pocket defect in Spanish-style green olives by the halophile Celerinatantimonas sp.

Gas pocket defect causes substantial losses every season to Spanish-style green table olive processors. This defect has been thought to be caused by microorganisms that are able to produce gaseous compounds that break the flesh and/or the epidermis of olive fruits. This study was focused on the search for the microorganism actually responsible for this spoilage. Metataxonomy analysis of industrial spoiled brines demonstrated the presence of Celerinatantimonas as the most probable source leading to gas pocket formation. Several bacterial isolates were obtained from different industrial spoiled brines whose 16S rRNA sequence closest homologue was Celerinatantimonas diazotrophica (94–96% similarity). Vigorous gas production (H 2 and CO 2 ) by these isolates in broth cultures was confirmed. Inoculation of microbial pellets from one of these spoiled brines did indeed provoke gas pocket formation in fresh batches of Spanish-style green olives. Although the species C. diazotrophica has been previously reported in metataxonomy studies in samples of table olives, this is the first time that it was isolated from fermenting table olive samples. In addition, this is the first report that associates this species to the gas pocket defect in table olives. Thus, inoculation with one of the wild-type isolates identified as C. diazotrophica in table olive brines confirmed the involvement of this microorganism in the formation of the gas pocket defect in Spanish-style green olives. • Celerinatantimonas was detected by metataxonomy in every spoiled table olive brine. • Celerinatantimonas was isolated from brines of table olives with gas pockets. • Gas pocket defect in olives was reproduced by Celerinatantimonas inoculation. • Celerinatantimonas yields acetic acid-ethanol-H 2 -CO 2 disturbing lactic acid fermentation.

Authentication of Greek PDO Kalamata Table Olives: A Novel Non-Target High Resolution Mass Spectrometric Approach.

Food science continually requires the development of novel analytical methods to prevent fraudulent actions and guarantee food authenticity. Greek table olives, one of the most emblematic and valuable Greek national products, are often subjected to economically motivated fraud. In this work, a novel ultra-high-performance liquid chromatography–quadrupole time of flight tandem mass spectrometry (UHPLC-QTOF-MS) analytical method was developed to detect the mislabeling of Greek PDO Kalamata table olives, and thereby establish their authenticity. A non-targeted screening workflow was applied, coupled to advanced chemometric techniques such as Principal Component Analysis (PCA) and Partial Least Square Discriminant Analysis (PLS-DA) in order to fingerprint and accurately discriminate PDO Greek Kalamata olives from Kalamata (or Kalamon) type olives from Egypt and Chile. The method performance was evaluated using a target set of phenolic compounds and several validation parameters were calculated. Overall, 65 table olive samples from Greece, Egypt, and Chile were analyzed and processed for the model development and its accuracy was validated. The robustness of the chemometric model was tested using 11 Greek Kalamon olive samples that were produced during the following crop year, 2018, and they were successfully classified as Greek Kalamon olives from Kalamata. Twenty-six characteristic authenticity markers were indicated to be responsible for the discrimination of Kalamon olives of different geographical origins.

Panel performance, discrimination power of descriptors, and sensory characterization of table olive samples

AbstractThe COI/OT/MO No. 1/Rev. 2—November 2011 method establishes the necessary criteria and procedure for the sensory analysis of table olives by a group of 8–10 expert/selected tasters and a panel leader. The performance of each individual taster and the whole panel was monitored on a regular basis, involving the analysis of replicated samples and retraining of tasters with references. Univariate and multivariate (two‐way analysis of variance, Line plot, Eggshell plot, PCA, Tucker‐1 plot) statistical techniques by the open‐source software PanelCheck V 1.4.2—2015 were applied. From the analysis of the data, hardness is quite highlighted for all assessors indicating that the panel agrees well for this characteristic, while for remaining attributes (salty, bitter, acid, fibrousness, and crunchiness) the situation is more complex and was analyzed case by case.Practical ApplicationsIn this study, assessors having good discrimination ability and repeatability were identified, and in the same time we acquired information regarding the difficulty to recognize/evaluate some attributes. These results were also used to investigate on the discrimination power of the descriptors.

Application of ISSR-PCR as a rapid method for clustering and typing of yeasts isolated from table olives

Table olives harbour a variable microbial population, dominated by lactic acid bacteria and yeasts. Clarifying the effect of the yeast population during table olive fermentation requires methods for yeast species identification. Until now, the most used molecular methods (culture-dependent and -independent) are limited to species level identification, whereas RAPD-PCR is primarily chosen when strain typing is required. In this work, species identification by sequencing of the ITS1–5.8S rDNA–ITS4 region, was followed by inter-simple-sequence-repeat-anchored PCR (ISSR-PCR) using the (CAG)4 primer, to evaluate its suitability for species clustering and strain typing of the yeast population from table olives. Yeast were isolated from ten table olive samples: seven samples were purchased from local markets (sliced, naturally fermented, crushed and Spanish-style fermented), and three samples were from pilot fermentations (Spanish-style fermented). Ten yeast species were identified by sequencing that were correctly clustered by ISSR-PCR, but without a clear association with the type of olive processing. ISSR-PCR revealed 57 different profiles into 254 total isolates. Citeromyces nyonsensis (39.4%) and Yarrowia deformans (22.2%), which have not previously been associated to table olives, showed high intraspecific variability. ISSR-PCR using (CAG)4 primer is a valuable method for identification and strain typing of yeast from table olives.

Pigment changes during preservation of green table olive specialities treated with alkali and without fermentation: Effect of thermal treatments and storage conditions

Large proportions of Cu-chlorophyll complexes have been quantified in certain commercial products of table olives with a strikingly bright green colour and labelled “Green olives in soda” and Campo Real-style in Spain, or Castelvetrano-style in Italy. Previous studies have shown that such compounds are not formed naturally during the processing step of these green table olive specialities. The present study aimed to discern whether the formation of Cu-chlorophyll complexes occurs spontaneously during the shelf-life of table olives or is the result of the deliberate addition of Cu (II) salts. The effect of different preservation conditions on the final pigment composition of table olives was investigated. To this end, processed fruits were packed in non-acidified or acidified brine and subjected to sterilization or pasteurization treatments, respectively. Pheophytinization of the chlorophyll compounds was the main reaction that took place during two years of storage and minor complexation of the chlorophyll structure with Cu was also observed. Up to ten different Cu-chlorophyll complexes were detected after 24 months of packing the olives, representing between 1 and 7.5% of the total chlorophyll pigments, depending on the temperature and pH values during storage. In no case was a bright green colour on the olive surface observed, and the values of total chlorophyll pigments were far from the high proportions (up to 99%) that have been quantified in alkali-processed commercial table olives without fermentation. These results demonstrated that the copper complexes were formed as a consequence of the deliberate addition of Cu (II) salts at some stage of the table olives' elaboration or preservation. The quantitative determination of copper chlorophyll complexes in commercial table olive samples with a suspiciously bright green colour is necessary to detect such bad processing practices.

Radionuclide and heavy metal content in the table olive (Olea europaea L.) from the Mediterranean region of Turkey

This study presents the concentrations of radionuclides and heavy metals in twenty-six table olive (Olea europaea L.) samples, and an assessment of the health risks associated with their consumption. The samples were collected from different towns in the Mediterranean region of Turkey, one of the major olive-producing countries in the world. The average activity concentrations of 226Ra, 232Th, 40K, and 137Cs in the edible parts of the table olive samples were found as 37.9 ? 4.1, 7.1 ? 0.5, 274.6 ? 14.7, and 7.2 ? 0.7 Bqkg (dw), respectively, by using a gamma ray spectrometer. The effective radiation dose due to the intake of these radionuclides through ingestion of olive samples varied from 3.4 to 22.7 ?Sv with an average value of 11 ? 1 ?Sv. The average concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, and Pb in the edible parts of the table olive samples were determined as 2.04, 11.08, 166.60, 0.20, 10.29, 13.81, 14.34, 4.50, and 4.55 ?gg?1, respectively, by using an inductively coupled plasma optical emission spectrometer. Based on the measured content of the radionuclides and heavy metals, the results imply that table olives are safe for human consumption.

Assessment of Table Olives’ Organoleptic Defect Intensities Based on the Potentiometric Fingerprint Recorded by an Electronic Tongue

Table olives are prone to the appearance of sensory defects that decrease their quality and in some cases result in olives unsuitable for consumption. The evaluation of the type and intensity of the sensory negative attributes of table olives is recommended by the International Olive Council, although not being legally required for commercialization. However, the accomplishment of this task requires the training and implementation of sensory panels according to strict directives, turning out in a time-consuming and expensive procedure that involves a degree of subjectivity. In this work, an electronic tongue is proposed as a taste sensor device for evaluating the intensity of sensory defects of table olives. The potentiometric signal profiles gathered allowed establishing multiple linear regression models, based on the most informative subsets of signals (from 24 to 29 recorded during the analysis of olive aqueous pastes and brine solutions) selected using a simulated annealing meta-heuristic algorithm. The models enabled the prediction of the median intensities (R 2 ≥ 0.942 and RMSE ≤ 0.356, for leave-one-out or repeated K-fold cross-validation procedures) of butyric, musty, putrid, winey-vinegary, and zapateria negative sensations being, in general, the predicted intensities within the range of intensities perceived by the sensory panel. Indeed, based on the predicted mean intensities of the sensory defects, the electrochemical-chemometric approach developed could correctly classify 86.4% of the table olive samples according to their trade category based on a sensory panel evaluation and following the International Olive Council regulations (i.e., extra, 1st choice, 2nd choice, and olives that may not be sold as table olives). So, the satisfactory overall predictions achieved demonstrate that the electronic tongue could be a complementary tool for assessing table olive defects, reducing the effort of trained panelists and minimizing the risk of subjective evaluations.

Sensory classification of table olives using an electronic tongue: Analysis of aqueous pastes and brines

Table olives are highly appreciated and consumed worldwide. Different aspects are used for trade category classification being the sensory assessment of negative defects present in the olives and brines one of the most important. The trade category quality classification must follow the International Olive Council directives, requiring the organoleptic assessment of defects by a trained sensory panel. However, the training process is a hard, complex and sometimes subjective task, being the low number of samples that can be evaluated per day a major drawback considering the real needs of the olive industry. In this context, the development of electronic tongues as taste sensors for defects’ sensory evaluation is of utmost relevance. So, an electronic tongue was used for table olives classification according to the presence and intensity of negative defects. Linear discrimination models were established based on sub-sets of sensor signals selected by a simulated annealing algorithm. The predictive potential of the novel approach was first demonstrated for standard solutions of chemical compounds that mimic butyric, putrid and zapateria defects (≥93% for cross-validation procedures). Then its applicability was verified; using reference table olives/brine solutions samples identified with a single intense negative attribute, namely butyric, musty, putrid, zapateria or winey–vinegary defects (≥93% cross-validation procedures). Finally, the E-tongue coupled with the same chemometric approach was applied to classify table olive samples according to the trade commercial categories (extra, 1st choice, 2nd choice and unsuitable for consumption) and an additional quality category (extra free of defects), established based on sensory analysis data. Despite the heterogeneity of the samples studied and number of different sensory defects perceived, the predictive linear discriminant model established showed sensitivities greater than 86%. So, the overall performance achieved showed that the electrochemical device could be used as a taste sensor for table olives organoleptic trade successful classification, allowing a preliminary quality assessment, which could facilitate, in the future, the complex task of sensory panelists.

Sensory evaluation and consumer perception of some commercial green table olives

PurposeThe objective of this study is to evaluate the physico‐chemical and sensorial characteristics of some commercial green table olives. Also, it seeks to elaborate the sensorial background of consumer preferences of different green table olives.Design/methodology/approachFour green table olive samples (Çelebi, Domat, Kaba, and Ayvalık) commonly consumed in Turkey were chosen and collected from a local producer. Dimensional measures, salt content, pH value, oil content, titrable acidity, L value, a* value, b* value and texture of samples were assessed by the AOAC methods. A panel described and measured the appearance (greenness, yellowness, globeness), aroma (fresh olive, vinegary, soapy, musty), flavour (sour, salty, bitter, hay, oily) and texture properties (firmness, flesh/stone adherence, fibrousness, watery). In addition, 50 consumers evaluated hedonic values.FindingsThe salt content, pH value, oil content, titrable acidity, L value, a* value, b* value and texture of samples were found to following values 2.91‐5.46 percent, 2.80‐3.97, 4.67‐18.71 percent, 0.59‐1.40 percent, 49.96‐69.56, 1.35‐17.91, 19.57‐45.47 and 434.1‐895.7 g. Although prepared with the same technique, many properties of the olives were found different. This difference affected consumer preference and buying intentions as well.Research limitations/implicationsThe paper provides scientific data for researchers to design similar sensory descriptive analyses for different table olive samples.Originality/valueThe paper is helpful both to consumers and traders to determine the proximate and sensory attributes of commercial green olive samples.

Simultaneous Determination of Squalene, α-Tocopherol and β-Carotene in Table Olives by Solid Phase Extraction and High-Performance Liquid Chromatography with Diode Array Detection

Olives, the fruit of the Olea europaea tree, are highly appreciated in olive oil and table olives (20 % of crops) not only for their flavor but also for their nutritional properties, especially for antioxidant compounds such as squalling (SQ), α-tocopherol (TH) and β-carotene (BC). This paper presents a new analytical method for simultaneously determining SQ, TH and BC in table olives by using solid phase extraction (SPE) and high performance-liquid chromatography with diode array detection (HPLC-DAD), avoiding the classic saponification process. The correlation coefficients of calibration curves of the analyzed compounds ranged from 0.998 to 0.999, and the recoveries were in the range of 89.4–99.6 %. The validated method was used to analyze 30 table olive samples from Italy for their content of SQ (537–1,583 mg kg−1), TH (21–90 mg kg−1) and BC (0.4–2.6 mg kg−1). Finally, experiments with HPLC-MS were conducted to compare this novel method with the classic saponification procedure.

Identification and quantification of metallo-chlorophyll complexes in bright green table olives by high-performance liquid chromatrography-mass spectrometry quadrupole/time-of-flight.

Five different samples of table olives, two regular Spanish table olives and three "bright green table olives", have been analyzed by HPLC-MS/MS to determine their pigment profile. Typical pigment profiles of almost all table olives show primarily chlorophyll derivatives lacking metals (e.g., pheophytin a/b and 15(2)-Me-phytol-chlorin e(6)). Bright green table olives have a unique profile including metallo-chlorophyll complexes (Cu-15(2)-Me-phytol-chlorin e(6) with 26-48% and Cu-pheophytin a with 3-18%) as their major pigments. New tentative structures have been identified by MS such as 15(2)-Me-phytol-rhodin g(7), 15(2)-Me-phytol-chlorin e(6), 15(2)-Me-phytol-isochlorin e(4), Cu-15(2)-Me-phytol-rhodin g(7), Cu-15(2)-Me-phytol-chlorin e(6), and Cu-15(2)-Me-phytol-isochlorin e(4), and new MS/MS fragmentation patterns are reported for Cu-15(2)-Me-phytol-rhodin g(7), Cu-15(2)-Me-phytol-chlorin e(6), Cu-pheophytin b, Cu-pheophytin a, Cu-pyropheophytin b, and Cu-pyropheophytin a. The presence of metallo-chlorophyll derivatives is responsible for the intense color of bright green table olives, but these metallo-chlorophyll complexes may be regarded as a "green staining" defect that is unacceptable to consumers.

Separation of Olive Proteins Combining a Simple Extraction Method and a Selective Capillary Electrophoresis (CE) Approach: Application to Raw and Table Olive Samples

A simple extraction method was developed to extract proteins from olive samples based on chloroform/methanol extraction followed by a protein precipitation with cold acetone. Then, a capillary electrophoresis (CE) method was carried out using an acid buffer (1 M formic acid at pH 2) to ensure a positive net charge for proteins and a neutral charge for potential interferents as polyphenols. The method developed was applied to raw and table olive samples. Interestingly, raw olive samples showed differences in protein profiles depending upon the botanical variety of olives and their geographical region. Protein profiles obtained for table olives also showed differences according to the sample treatment. Thus, a signal reduction in the electropherograms obtained for black olives was observed in comparison to those achieved for treated green olives. In this work, the use of protein profiles was demonstrated to be a powerful tool for studying variations among olive samples.

Characterisation of table olive cultivar by NIR spectroscopy

NIR spectroscopy is proposed as a rapid and effective analytical method for the identification of the cultivar of table olives. The study was particularly focused on the Taggiasca cultivar. A set of 46 samples representative of the Taggiasca production area was analysed together with 43 samples of table olives of different cultivars. After feature selection, LDA and SIMCA were applied to the NIR data as classification and class-modelling techniques, respectively. The excellent results obtained by NIR spectroscopy (mean specificity of the models 82.0%, sensibility >90%) were then compared to those obtained by the gas chromatographic (GC) determination of the fatty acids composition of the oils extracted from the samples of table olives. Finally, in order to test the potential synergy among different sources of information, the employed NIR and chemical variables were joined, but only a small improvement of the results obtained by NIR alone was reached.

Análisis sensorial de aceituna de mesa: II. Aplicabilidad práctica y correlación con el análisis instrumental

A sensory assessment of different samples of table olives from Campo Real (Madrid) was made by a professional panel. A study of the physico-chemical and rheological properties of the olives was also done. The objective of the study was to correlate sensory and instrumental data (color, pH, firmness…) in order to identify the instrumental parameters that better explain the sensation when eating table olives. A significant inverse correlation is observed between the polyphenol content and the color of olives and brine. The sugar content is directly proportional to the color intensity quantified by the panel. A high correlation between net absorbance and sensory evaluation is observed, showing the efficiency of the scales used in the study. Moreover, the different sensory parameters where correlated among them to evaluate their contribution to the global evaluation of the product.

ICP-MS analysis of a series of metals (Namely: Mg, Cr, Co, Ni, Fe, Cu, Zn, Sn, Cd and Pb) in black and green olive samples from Bursa, Turkey

Ninety-two black and green table olive samples from the Bursa, Turkey were analyzed. The olives were sampled from 56 brands, four processing methods and three packing types. The concentration of Mg, Cr, Co, Ni, Fe, Cu, Zn, Sn, Cd and Pb were measured by inductively coupled plasma mass spectrometry (ICP-MS). While the most concentrated element was Mg (125.11 ± 5.02), Co (0.09 ± 0.01) had the lowest concentration in tested olive samples. The levels of the ten metals studied are within safe limits. The data here obtained will be valuable in complementing available food composition data, and estimating dietary intakes of heavy metals in Turkey. The metals Mg, Fe, Zn, Sn and Pb presented significant differences ( p < 0.05) in content between two types, hence processing method, brand and packing material must influence their content.

DETERMINATION OF LACTIC, ACETIC, SUCCINIC, AND CITRIC ACIDS IN TABLE OLIVES BY HPLC/UV

This paper describes a procedure performed by high performance liquid chromatography/UV detection for quantification of the major carboxylic acids in table olives (lactic, acetic, succinic, and citric acids); derivatization of carboxylic acids with O-(4-nitrobenzil)-N,N′diisopropylisourea (PBNDI) was performed. The sample preparation involved deproteination with ethanol and the use of strong cation-exchange resin (Dowex 50W-X8) to liberate the free carboxylic acids. The same resin was used to remove the excess of derivatizing reagent. The chromatographic separation was achieved using reverse-phase column C18(ODS). The mobile phase used was a gradient of water and acetonitrile at a flow-rate of 1 mL/min. The effluent was monitored using a UV detector at 265 nm. The method allowed for well-resolved peaks of lactic, acetic, succinic, and citric acids in less than 25 min. Precision and recovery assays were performed with good results for the acids under study. Nineteen samples of table olives available on the Portuguese market, including nine samples of green olives and 10 samples of black olives, were successfully monitored applying this methodology. The concentrations of carboxylic acids are expressed in percentage of moist olive pulp and ranged from not detected to 477.3 mg of lactic acid/100 g of moist olive pulp and 9.43 to 232.1 mg of acetic acid/100 g of moist olive pulp. Citric acid was detected only in two samples of green table olives with concentrations of 24.7 and 188.3 mg/100g of moist olive pulp. Succinic acid was detected in five samples of green table olives ranging from 10.1 to 25.8 mg/100 g moist olive pulp, and in two samples of black table olives with concentrations of 10.7 and 29.4 mg/100 g of moist olive pulp.