The flavor of dry cured ham explains the high appreciation of this product and it determines consumer acceptance. Volatile compounds provide valuable information about the odor and sensory quality of ...dry cured hams. Since amino acids are the origin of some volatile compounds of dry cured ham, the volatile and amino acid compositions of forty-one dry cured hams from Spain and France were determined to establish associations between them. The samples included different pig breeds (non Iberian vs. Iberian), which were additionally affected by different maturation times and feeding types (acorn vs. fodder). Results showed that 20 volatile compounds were able to distinguish Iberian and non Iberian hams, and 16 of those had relevant sensory impact according to their odor activity values. 3-Methylbutanol, 2-heptanol and hexanal were among the most concentrated volatile compounds. In the case of non-volatile compounds, the concentrations of amino acids were generally higher in Iberian hams, and all the amino acids were able to distinguish Iberian from non Iberian hams with the exception of tryptophan and asparagine. A strong correlation of some amino acids with volatile compounds was found in the particular case of alcohols and aldehydes when only Iberian hams were considered. The high correlation values found in some cases proved that proteolysis plays an important role in aroma generation.
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 152-Me-phytol-chlorin e6). Bright green table olives have a unique profile including metallo–chlorophyll complexes (Cu-152-Me-phytol-chlorin e6 with 26–48% and Cu-pheophytin a with 3–18%) as their major pigments. New tentative structures have been identified by MS such as 152-Me-phytol-rhodin g7, 152-Me-phytol-chlorin e6, 152-Me-phytol-isochlorin e4, Cu-152-Me-phytol-rhodin g7, Cu-152-Me-phytol-chlorin e6, and Cu-152-Me-phytol-isochlorin e4, and new MS/MS fragmentation patterns are reported for Cu-152-Me-phytol-rhodin g7, Cu-152-Me-phytol-chlorin e6, 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.
The methodology of sensory assessment (“panel test”) of virgin olive oil (VOO) is the sensory method included in international regulations and its application is compulsory in trading. Despite its ...application has been a success in authenticity of VOO quality, the application of panel test is not exempt of heated debates and controversies among olive oil actors that sometimes surpasses scientific arguments. Problems are consequence of some disagreements in the evaluation of the same VOOs from different testing laboratories, and today, there is a clamor for its enhancement from a considerable part of the industrial sector. The thin line that exists between the absence of sensory defects in extra‐VOOs and a very slight sensory defect that may be perceived in some VOOs by some tasters is in the origin of the controversy. Thus, this work is focuses on providing practical solutions to the current concerns of Panel Test after analyzing proposals evaluating aroma descriptors from chemistry, examining flaws of panel test and strengthening its weak points.
Practical Applications: The work describes a strategy that combines volatiles and sensory descriptors for avoiding disagreements with results provided by non‐recognized testing laboratories, and proposes a blueprint for improving the process of training tasters with reference materials.
Panel test of virgin olive oil (VOO) is the only sensory assessment included in international regulations. Although its application has been a success, some problems based on disagreements among sensory qualifications of VOOs by panel tests have been reported. The article proposes solutions and future challenges to enhance and strengthen panel test with the assistance of the volatile compounds.
This work studies the relationship between 45 volatile compounds and 17 sensory attributes (13 flavour perceptions) of dry-cured hams. Volatile compounds were quantified by SPME-GC while the sensory ...assessment was carried out by 13 panellists. GC-sniffing was used to determine the odour impact zones of the chromatogram. The odour thresholds of the volatile compounds and their sensory characterisation were determined by dilution analysis. Six sensory attributes (acorn odour and flavour, rancid odour, rancid taste, fat rancid and fat pungent flavours) were explained by regression equations (adjusted –R2⩾0.70) based on ten compounds: benzaldehyde, 2-heptanone, hexanal, hexanol, limonene, 3-methylbutanal, 3-methylbutanol, 2-nonanone, octanol, pentanol. Acorn flavour attribute was successfully emulated by mixing the volatile compounds selected by the equation. Its odour was evaluated by assessors that gave a sensory description that matches with the target. All the procedures performed for the elucidation of volatile-attribute relations showed a basic agreement in their results.
Competition and interaction phenomena among volatiles during their adsorption process by solid phase microextraction (SPME) fibers in static headspace sampling procedure (SHS) cast doubt on its ...ability to quantify virgin olive oil volatiles. SPME fibers being excellent traps, their use was analyzed with a new device allowing the concentration of volatiles in a dynamic headspace sampling procedure (DHS). A central composite experimental design optimized the main variables of the device (4 g sample weight, 40 °C temperature, 150 mL/min flow rate, 50 min adsorption time), while values of the analytical quality control parameters of the method (repeatability, limits of detection and quantification, working range, sensitivity, and resolution) were compared with those ones from static headspace. DHS shows better precision results for aldehydes and alcohols than SHS and allowed analyzing higher concentrations with no problem of saturation. In 19 of 28 compounds analyzed in 50 samples the chromatographic areas were higher when running DHS. The concentration values of volatile compounds in these samples after applying SHS and DHS are discussed together with the ability of the new method for distinguishing virgin olive oil by their categories (extra virgin, virgin, and lampante) by the volatiles quantified in commercial oils.
Food authentication has been evolving continually to situations that were basically governed by a global market trend. Analytical techniques have been developed or modified to give plausible ...solutions to the devious adulterations at each moment. Classical tests have largely been replaced with newer technical procedures, most of which are based on gas chromatography, with some being based on high-performance liquid chromatography. Determination of
trans-fatty acid and sterolic composition, together with sterol-dehydration products, have been used most frequently used to detect contamination and adulteration. Sophisticated new adulterations, e.g., olive oil with hazelnut oil, represent a new challenge for the next millennium, although suggestive proposals for detecting these kinds of adulterations are emerging with the contribution of databases and mathematical algorithms.
The latest regulation to protect unique virgin olive oils that have particular properties is called protected designations of origin (PDOs), and it has proven to be a successful way to protect ...quality and geographical authenticity. Nevertheless, sometimes the registration of new PDOs associated to new demarcations of geographic areas are almost based on administrative aspects rather than objective chemical data. In this study, the ability of chemical compounds of virgin olive oils with PDO is analyzed that are not labile and their concentrations do not vary over time − fatty acids, alcohols, hydrocarbons, methyl‐sterols and sterols − to differentiate them from those produced in their neighboring geographical areas. Three cases in the Andalusia region (Southern Spain) that combine pedoclimatic characteristics and variations of cultivar have been studied (9 areas with PDO and 3 non‐PDO areas). With a modified procedure of ANOVA analysis − the Brown–Forsythe test, chemical compounds that show good characteristics for the classification of samples are selected, and this ability is later checked by applying the unsupervised algorithm of Principal Component Analysis. Differences in their chemical composition are found when comparing the PDO oils with those produced in the neighboring olive tree groves despite chemical criteria are not among the most decisive factors for registering PDOs.
Practical Applications: The practical application of this study is centered in the possibilities of the chemical composition of virgin olive oil being used to differentiate the PDO authenticity. The results of this study proves that it is difficult to establish discreet limits defining the PDO areas. The current physical‐chemical information should be used by both administration and PDO councils to supplement arguments for approving or denying new PDOs.
Chemistry can assist the authenticity of virgin olive oil PDOs. The registration of new PDOs associated with new demarcations of geographic areas are almost based on administrative aspects rather than objective chemical data. In this work, chemical compounds that show good characteristics for the classification of samples are selected, and their classifying ability is later checked.
Chemistry can assist the authenticity of virgin olive oil PDOs. The registration of new PDOs associated with new demarcations of geographic areas are almost based on administrative aspects rather than objective chemical data. In this work, chemical compounds that show good characteristics for the classification of samples are selected, and their classifying ability is later checked.
This paper evaluates the performance of the current analytical methods (standard and widely used otherwise) that are used in olive oil for determining fatty acids, triacylglycerols, mono- and ...diacylglycerols, waxes, sterols, alkyl esters, erythrodiol and uvaol, tocopherols, pigments, volatiles, and phenols. Other indices that are commonly used, such as free acidity and peroxide value, are also discussed in relation to their actual utility in assessing quality and safety and their possible alternatives. The methods have been grouped on the basis of their applications: (i) purity and authenticity; (ii) sensory quality control; and (iii) unifying methods for different applications. The speed of the analysis, advantages and disadvantages, and multiple quality parameters are assessed. Sample pretreatment, physicochemical and data analysis, and evaluation of the results have been taken into consideration. Solutions based on new chromatographic methods or spectroscopic analysis and their analytical characteristics are also presented.
The oxidation reactions that take place in virgin olive oil under moderate conditions involved the combined effect of antioxidant and prooxidant compounds. Given the complexity of oxidation processes ...of multicomponent matrices, there is still a need to develop new methods with a dynamic approach to study the persistence of the compounds with healthy properties. This work studied the joint evolution of them, including phenols and pheophytin a, modeling their tendency during a real storage. The regression equations performed with the total phenol concentration showed that around 2% of the concentration was lost every month. Simultaneously, the progress of oxidation was evaluated by mesh cell incubation and Fourier transform infrared analysis. This method pointed out that, in the presence of light, the prooxidant effect of pigments was able to mask the protective effect of phenols, until the pheophytin a concentration was lower than 1 mg/kg. The antioxidant effect of phenols was less remarkable when the concentration loss was 35% or more.
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•Defective virgin olive oils were soft-deodorized under different conditions.•Soft-deodorized oils were analyzed to determine volatiles, phenols, ppps and faees.•Optimized ...soft-deodorization (100°C, 60min) produced minor chemical changes.•These results will help to detect soft-deodorized VOO in EVOO in further works.
The potential adulteration of extra virgin olive oil (EVOO) with soft-deodorized virgin olive oil (VOO) has raised the interest of researchers in investigating this fraud in recent years. The objective of this study was to determine chemical changes occurring after a soft-deodorization process in terms of volatiles, fatty acid ethyl esters (FAEEs) and pyropheophytins (PPPs) concentrations in VOOs. After testing several conditions (80, 100 and 130°C, for 30 and 60min), the parameters of 100°C and 60min were considered as the optima. These conditions allowed removing volatiles responsible for sensory defects with low losses of total phenols (14%–32%), and values of PPPs (11.83%) and FAEEs (34.53mg/kg) lower than the limits of standard regulations. The experiments show that soft-deodorized VOOs could be added up to 50% to EVOOs and current standard methods would not detect this kind of adulteration.
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