•Musty odour is one of the most usual taints in food linked to microorganism activity.•These compounds are present at very low levels and have very low sensory thresholds.•Its analysis requires ...preconcentration together with highly sensitive GC detectors.•Many extraction techniques have been applied to determine musty compounds.•Instrumentation developments can increase selectivity/sensitivity for these compounds.
One of the most common taints in foods is a musty or earthy odour, which is commonly associated with the activity of microorganisms. Liquid foods, particularly wine and water, can be affected by this defect due to the presence of certain aromatic organic compounds at very low concentrations (ng/L) consistent with human threshold perception levels. The volatile compounds responsible for a mouldy off-aroma include approximately 20 compounds, namely, haloanisoles, geosmin, 2-methylisoborneol, several alkyl-methoxypyrazines, 1-octen-3-ol, 1-octen-3-one, trans-octenol, 3-octanone, fenchol and fenchone. Methods for determining these very low concentrations of odour compounds must be extremely sensitive and selective with efficient preconcentration treatments. A number of extraction techniques based on LLME (liquid–liquid microextraction), SPME (solid-phase microextraction) or SBSE (stir-bar sorptive extraction) can be applied and should be selected on a case-by-case basis. Moreover, recent developments in GC instrumentation coupled to different detection systems can effectively increase the selectivity and sensitivity of the analysis of target compounds.
•It was the first time that Argentinian wine and balsamic vinegars were studied.•UV–vis and fluorescence spectroscopies were used for a vinegar characterization.•Argentinian wine and balsamic ...vinegars were also characterized by sensory analysis.•Differences between acetification, origin and Argentinean productions were shown.•These results encourage the production of high-quality vinegars and new regulations.
In Argentina, vinegars are cheap agro-food products without exhaustive regulation and the production of high-quality vinegars has not been exploited yet. In fact, Argentinean vinegars have not been studied. In this context, a first study of Argentinean balsamic and wine vinegars was carried out by a sensory and spectroscopic characterization and by a comparison with well-recognized European vinegars. For that, ultraviolet–visible and fluorescence spectroscopies were applied together with principal component analysis (PCA) and parallel factor analysis (PARAFAC) performed on each data set, respectively. Results showed differences between acetification processes, origin countries and a wide variability within Argentinean production. The sensory characterization on Argentinean wine vinegars was performed by triangular and ordering preference tests showing statistically significant preferences toward the traditional and the rapid vinegars. This work highlights the effect of production on quality in order to provide added value to the Argentinean vinegars.
•Non-destructive sampling combined with HS-GC-IMS or HS-GC–MS was used for Iberian ham differentiation.•A comparison of the suitability of both detectors and the non-destructive sampling was ...performed.•HS-GC-IMS proved to be more sensitive than HS-GC–MS by detecting more VOCs.•HS-GC-MS provided more accurate quantitative results for VOCs analysis of Iberian ham.•Non-destructive sampling and both techniques can be used as a targeted tool to guarantee ham quality.
The study of volatile compounds obtained by gas chromatography (GC) coupled to mass spectrometry (MS) or ion mobility spectrometry (IMS) may be very useful to protect food quality, especially when using a non-destructive sampling method. In this work, the authentication of the highly appreciated dry-cured Iberian ham by those techniques was studied and compared. The results obtained show the suitability of a non-destructive sampling method coupled to headspace sampling (HS)-GC-IMS or HS-GC–MS to determine volatile markers in the feeding Iberian pig regime. Although both methods were suitable to differentiate the ham categories, HS-GC-IMS was more sensitive detecting a higher number of compounds than HS-GC–MS, which provided accurate qualitative results. The results of principal component analysis showed that ethanol, 2-propanol and 3-methylbutanol, identified by HS-GC-IMS, and 3-methylbutanal and heptane, identified by HS-GC–MS, could be considered potential markers to identify ham from different feeding regimes.
•UV–vis spectroscopy was used for grape-must caramel quantification in vinegars.•Balsamic and PDO vinegars’ grape-must caramel content was predicted.•Univariate and multivariate calibration ...approaches were assessed and compared.•Prediction results were compared with those obtained by other spectroscopies.•The results encourage UV–vis as an alternative tool for monitoring caramel addition.
The addition of E-150d caramel, known as grape-must caramel in vinegars, is a legal but without limitation practice in Spanish wine vinegars, as those with a protected designation of origin (PDO), for unifying the final colour of different batches and barrels. It is also used in the production of ‘Balsamic vinegar of Modena’ vinegars, with a maximum addition fixed at 2% v/v by law. Although its quantification in vinegars was studied by other techniques, there is still not any official method for it. Therefore, UV–vis spectroscopy was assessed as a quick analytical method able to quantify grape-must caramel in Balsamic vinegars of Modena and Spanish PDO wine vinegars. Univariate and multivariate calibrations were assessed for this quantification. Results demonstrated the ability of UV–vis spectroscopy coupled with multivariate calibration in the quantification of grape-must caramel, predicting caramel amounts under 2% v/v in both Balsamic and PDO wine vinegars.
The amino acids present in foods and beverages affect the quality of these products and they play an important role in enology. Amino acids are consumed by yeasts as a source of nitrogen during ...alcoholic fermentation and are precursors of aroma compounds. In this review various chromatographic methodologies for the determination of amino acids are described, and specific applications for the analysis of amino acid content are discussed. Amino acids usually need to be derivatized to make them more detectable. Several derivatizing reagents have been employed for the determination of amino acids in enological applications, and each has its advantages and disadvantages.
•In general profile of Chilean sparkling wines stand out esters, alcohols and acids.•Headspace and immersion sequential extraction using two PDMS twisters was the best.•Traditional wines had higher ...presence of ethyl esters than Charmat wines.•Charmat wines presented higher amounts of acetic esters than traditional wines.
The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ketones were predominant in the Charmat wines. PCA and LDA confirmed the differences in the volatile profiles between the production methods (traditional vs. Charmat).
•Determination of biogenic amines using SPE and AQC as derivatization agent.•The concentration of biogenic amines present in vinegar are much lower than wines.•Balsamic and Pedro Ximenez vinegar ...present the highest amounts of biogenic amines.•Methylamine and phenyletylamine are not determined in any vinegar.•Red wine vinegars present a different profile of biogenic amines.
This paper reports the determination of biogenic amines by high-performance liquid chromatography (HPLC) and fluorescence detection after derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) in balsamic, apple, and red, white, and Sherry wine vinegars. A solid-phase extraction (SPE) with mixed-mode resins method was used before analysis. The method was successfully validated obtaining adequate values of selectivity, response linearity, precision, accuracy, and low detection and quantification limits. The total content of biogenic amines in vinegars ranged from 23.35 to 1445.2μg/L, being lower than those reported in wines. Putrescine was the amine that showed the highest concentrations in most samples. Methylamine and phenylethylamine were not determined in any vinegar. Balsamic and “Pedro Ximénez” Sherry vinegars reached the highest amounts of biogenic amines, while apple, white and Sherry wine vinegars had the lowest concentrations. Principal component analysis using the biogenic amines as variables, allowed to separate the different kind of vinegars, excepting red vinegars.
The traditional production of wine vinegar is a lengthy process with little or no microbiological control. The aim of this study was to shorten the acetification process via three different ...strategies: changes in wood type; barrel shape; and the inoculation of an
Acetobacter pasteurianus pure culture. The barrel shape was modified by constructing two prototypes with higher liquid–air interface. We compared the changes in acetic acid bacteria (AAB) population dynamics in these barrels with those of a submerged method. The wood type had no effect on the acetification length, whereas the shape of the barrel resulted in a significant shortening of the acetification length. Although the selected AAB strain did not always take over, it reduced the biodiversity of the AAB. The inoculated strain was predominant in oak barrels, whereas in the highly aerated prototypes
Gluconacetobacter species (
Ga. intermedius and/or
Ga. europaeus) displaced
A. pasteurianus, as what occurs in the submerged method.
A static headspace gas chromatography coupled to mass spectrometry (SHS–GC–MS) method was validated to determine several major volatile components during the production process of fruit vinegars. The ...method is simple, fast, linear in the working range, suitably sensitive, repeatable and reproducible, and has a good degree of accuracy for most of the compounds studied. Different conditions were tested in the production process of vinegars by means of double fermentation. The addition of SO2 and pectolytic enzymes produced a considerable increase in methanol and acetaldehyde, especially in strawberry purees, whereas pressing led to a loss of these volatile compounds. In the alcoholic fermentation of persimmon and strawberry purees, the Saccharomyces cerevisiae strain used had a great influence on the production of acetaldehyde and higher alcohols in wines. Considering the influence of these studied compounds in the final profile of the vinegars, our results showed that the S. cerevisiae strain isolated in this study produced the most suitable wine substrates for the production of vinegars. Moreover, semisolid fruit substrate provides better results than liquid substrate. Inoculated acetification in wood recipients yielded vinegars with a better volatile profile, as these contained higher levels of most compounds except acetaldehyde.
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•Dry-cured Iberian hams processed in different geographical locations were evaluated.•Experimental design was to process two legs from each pig in two different ...locations.•Olfactometric and sensory analysis of dry-cured Iberian ham was performed.•Geographical location influenced especially retronasal attributes of ham.•Ham initial composition and geographical location influenced on key odorants.
Olfactometric and sensory analyses have been applied to study the possible influence of the ripening chamber’s geographical location on the aroma sensory profiles and key odorants of Iberian ham. Dry-cured Iberian ham was obtained from 3 acorn-fed pigs and, for the first time, both of the participating production facilities, located in two different Andalusian municipalities with different altitudes above mean sea level, processed one of the two hind legs from each pig. The descriptive sensory profile of orthonasal and retronasal odours was determined by trained panellists, while odour-active compounds were determined by gas chromatography/mass spectrometry-olfactometry (GC/MS-O). The results obtained showed that, separately, both techniques enable Iberian ham samples to be differentiated by their ripening chamber’s geographical location. For sensory analysis, retronasal sensory analysis appeared to be the most suitable for this goal, highlighting the “meat broth odour” and “roasted nuts odour” descriptors which presented significant differences between geographical locations for samples from all pigs. Moreover, ripening chamber’s geographical location characteristics and the initial composition of the raw material seemed to influence the content of some odour-active compounds. The odour-active compound identified as octane/acetone and isobutanol were conditioned by the ripening chamber’s geographical location, while decanal/2-ethyl-1-hexanol, 1-undecanol, 2-furanmethanol and cis-2-nonenal were also influenced by the individual pig itself. This study showed that slight climatological differences due to the location of the ripening chamber seem to have somewhat of an influence on the aromatic profile.
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