Fabio Chinnici

Gas chromatography-mass spectrometry (GC-MS) characterization of volatile compounds in quality vinegars with protected european geographical indication.

The volatile composition of 26 premium quality vinegars belonging to three different protected geographical indications (traditional balsamic vinegar of Modena, balsamic vinegar of Modena, and sherry vinegar) has been characterized by means of a solid-phase extraction (SPE) gas chromatography-mass spectrometry GC-MS method. Among the about 90 quantified compounds, short-chain fatty acids, furanic compounds, enolic derivatives, and some esters were found to discriminate the samples as a consequence of differences in the extent of Maillard reactions, presence of alcoholic fermentation, or duration of wood aging.

SIMULTANEOUS DETERMINATION OF ORGANIC ACIDS, SUGARS, AND ALCOHOLS IN MUSTS AND WINES BY AN IMPROVED ION-EXCLUSION HPLC METHOD

ABSTRACT An HPLC method for the simultaneous quantification of the main carboxylic acids (including citric, tartaric, malic, shikimic, succinic, lactic, fumaric, and acetic acids), sugars (glucose and fructose), and alcohols (glycerol and ethanol) of musts and wine is proposed. Using a cation exchange column, improved separation of coeluting compounds (e.g., fructose vs. malic acid and succinic vs. shikimic acid) was achieved by moderate addition of tetarhydrofuran (THF) (4%) and n-propyl alcohol (n-PA) (5%) as organic modifier in the mobile phase. A factorial experiment was carried out for optimize acidity and temperature of elution. The method showed good linearity and precision and, as an application, was successfully applied to a must and a wine.

Discrimination of some European vinegars with protected denomination of origin as a function of their amino acid and biogenic amine content.

BACKGROUND Twenty-three amino acids and 11 amines were quantified in 37 premium quality European vinegars (traditional balsamic vinegar of Modena, balsamic vinegars of Modena and vinegars of Jerez) by an HPLC-DAD method after derivatisation with diethyl ethoxymethylenmalonate. Data were assessed in the light of the differences in technology and raw materials. RESULTS The total amount of amino acids ranged from 136 mg kg(-1) to 1450 mg kg(-1) in traditional balsamic vinegar of Modena and balsamic vinegar of Modena, respectively. Jerez vinegars had a mean content from 351 mg kg(-1) to 921 mg kg(-1) . Proline, glycine and γ-aminobutyric acid were the main amino acids while isoleucine was only found in balsamic vinegar of Modena at a concentration of <1 mg kg(-1) . Traditional balsamic vinegar of Modena had the lowest amount of biogenic amines. However, for all the vinegars, their concentration did not raise health issues. Based on the entire dataset, samples were successfully segregated and classified by means of principal component and cluster analysis. CONCLUSION The amino acid and amine content in vinegars is influenced by the production process and raw materials. They may potentially contribute in characterising the European premium quality vinegars also for authentication or anti-fraud purposes.

Effects of chitosan based coatings enriched with procyanidin by-product on quality of fresh blueberries during storage

The aim of this work was to evaluate the efficacy of an innovative edible coating, based on chitosan from mushrooms enriched with procyanidins extracted from grape seeds, on fresh blueberry quality maintenance, (weight loss, pH, dry matter, colour, firmness and antioxidant activity) and microbial growth, during 14 days of storage at 4 °C. For weight loss, pH and dry matter no relevant differences were detected among the control and the differently coated samples at each considered storage time. Chitosan and chitosan + procyanidins coatings promoted a slight decrease of luminosity and an increase of blue hue colour of blueberry samples during the whole storage period. The use of coating promoted an increase in the antiradical activity that was the highest in blueberries coated with chitosan + procyanidins. Microbiological analysis results indicated that the chitosan-based coated samples had a significantly higher yeast and mould growth inhibition compared to the uncoated sample.

Production of Volatile and Sulfur Compounds by 10 Saccharomyces cerevisiae Strains Inoculated in Trebbiano Must

In wines, the presence of sulfur compounds is the resulting of several contributions among which yeast metabolism. The characterization of the starter Saccharomyces cerevisiae needs to be performed also taking into account this ability even if evaluated together with the overall metabolic profile. In this perspective, principal aim of this experimental research was the evaluation of the volatile profiles, throughout GC/MS technique coupled with solid phase micro extraction, of wines obtained throughout the fermentation of 10 strains of S. cerevisiae. In addition, the production of sulfur compounds was further evaluated by using a gas-chromatograph coupled with a Flame Photometric Detector. Specifically, the 10 strains were inoculated in Trebbiano musts and the fermentations were monitored for 19 days. In the produced wines, volatile and sulfur compounds as well as amino acid concentrations were investigated. Also the physico-chemical characteristics of the wines and their electronic nose profiles were evaluated.

Growth, biogenic amine production and tyrDC transcription of Enterococcus faecalis in synthetic medium containing defined amino acid concentrations

The tyraminogenic potential of the strains Enterococcus faecalis EF37 and ATCC 29212 was investigated in a synthetic medium containing defined amounts of tyrosine and phenylalanine at different temperatures.

Influence of canopy-applied chitosan on the composition of organic cv. Sangiovese and Cabernet Sauvignon berries and wines.

The effects of canopy-applied chitosan on grapes and derived wine were evaluated in an organically managed mature vineyard. The experiment was performed on Sangiovese and Cabernet Sauvignon red grape cultivars, the application of a chitosan solution was compared to water spraying. Each treatment was applied 3 times (beginning and end of veraison, and pre-harvest) in a randomized block experimental design. Significant differences in (+)-catechin, (-)-epicatechin and procyanidin B2 amounts in berries and wines were detected in Cabernet Sauvignon but not in Sangiovese. Chitosan did not influence the berry skin anthocyanin and flavonol amount or t-resveratrol concentration in both skins and wines. A considerable increase in γ-aminobutyric acid (GABA), together with some other amino acids, ammonium and amines was observed in the berry flesh of cv. Cabernet Sauvignon. The increase in phenolic acids and nitrogenous compounds, especially GABA, in the pulp of Cabernet Sauvignon grapes suggests changes in stress response.

Sulfur free red wines through the use of grapevine shoots: Impact on the wine quality

Following a preliminary study to determine the possibility of using a grapevine shoot extract (VIN) as a sustainable alternative to sulfur dioxide (SO2), in this study, the chromatic features, phenolic composition, and sensory analysis of wines treated with VIN at two concentrations were studied during storage in bottle for the first time. The highest differences were found in phenolic compounds after 12months of storage in bottle. The VIN wines had a low content of free anthocyanins and were high in vinyl-pyranoanthocyanins, and B-type vitisins. Consequently, they showed better chromatic characteristics. Moreover VIN, especially at high dose, preserved non-anthocyanin phenolic compounds better than SO2. However, at this high dose some organoleptic properties were affected. VIN, when used at a low dose, is able to preserve wine composition without loss of quality.

Effect of a grapevine-shoot waste extract on red wine aromatic properties: Effect of a grapevine-shoot waste extract on red wine aromatic properties

BACKGROUND The use of a grapevine-shoot extract (VIN) is being studied as an alternative to sulfur dioxide (SO2 ). VIN stabilizes anthocyanins and preserves polyphenolic compounds, and thus improves chromatic wine properties. In this study, selected aroma compounds (esters, C13 -norisoprenoids, oxidation and vine-shoot-related compounds), sensory analysis and the olfactometric profile were determined in the wines treated with VIN at two concentrations. RESULTS Treatment with VIN hardly modified the content of esters and oxidation-related compounds in the wines. However, the high β-damascenone and isoeugenol contents and the increase in astringency at tasting in VIN wines were noteworthy, as were some odorant zones. All these were established as VIN markers after the chemometric data analysis. CONCLUSION These data revealed that only the lowest dose tested may be recommended as a suitable alternative to SO2 . Although some aromatic properties of these wines may change, these changes are not considered to affect the quality of the wines negatively. These results are useful for wineries, which face having to discover the aroma-related processes in the challenge of producing SO2 -free wines without detriment to their sensory properties.