Antonella Verzera

Biodiversity of indigenous Saccharomyces populations from old wineries of south-eastern Sicily (Italy): preservation and economic potential.

In recent years, the preservation of biodiversity has become an important issue. Despite much public discussion, however, current practices in the food industry seldom take account of its potential economic importance: on the contrary, the introduction of industrialized agriculture practices over large areas has often resulted in a dramatic reduction in biodiversity. In this paper, we report on the remarkable degree of biodiversity in the wine yeast populations naturally present in a small area of Sicily (Italy) where traditional (non-industrial) winery practices are still in place. Out of more than 900 Saccharomyces yeast isolates recovered from late spontaneous fermentations, we detected at least 209 strains. Most interestingly, when evaluated at the fermentation and technological level, a number of isolates were found to be superior to industrial yeast strains. Out of a selected group, isolates from two strains were used for experimental fermentations in a winery environment and the quality of the wines produced was assessed at the technological, quality and sensory levels. Given that the characteristics of the wines produced were found to be industrially appealing, the study demonstrated the economic potential of preserving the patrimony of Sicilian yeast biodiversity and highlighted the importance of maintaining traditional wine making practices.

On the Genuineness of Citrus Essential Oils. Part XLIII. The Composition of the Volatile Fraction of Italian Sweet Orange Oils (Citrus sinensis (L.) Osbeck)

ABSTRACT The composition of the volatile fraction of Italian sweet orange oil obtained from blond and blood pulp fruits has been studied by GC and GC/MS. The study has been carried out on 190 genuine oils obtained by “Pelatrice” and “FMC in-line” industrial processing during the 1991–92 season. More than 55 components have been identified in the oil, with limonene (ca. 95%) as the main component. Because of the relatively high percentage of octanal and decanal found in the oil, the carbonyl compounds are the most important components of the oxygenated fraction. The results obtained establish that the quantitative composition of sweet orange oil shows peculiar variations in many components during the season and greatly depends on the isolation procedure and the kind of fruit processed. Oil produced by the “Pelatrice” method has a lower monoterpene content and a higher aldehyde and alcohol content than the oil produced during the same time period by “FMC” process. Also, blood oils generally show a higher mo...

Citrus Essential Oils of Uruguay. Part I. Composition of Oils of Some Varieties of Mandarin

ABSTRACT The chemical composition of the cold-pressed oils obtained from three mandarin cultivars (“Comun,” “Malvasio” and “Ellendale”) and two mandarin hybrids (“Ortanique” and “Malaquina”) grown in Uruguay were examined using a combination of alumina column chromatography and capillary GC. Forty-five constituents were characterized in the oils with the limonene content varying from 75.26–96.23%. The composition and olfactory characteristics of these oils were compared with those of Italian mandarin oil and Uruguayan sweet orange oil. It was found that the “Ortanique” and “Ellendale” oils were very different from normal mandarin oil, with great similarity in composition and olfactory characteristics to sweet orange oil. The oil of “Malaquina” is also similar more to sweet orange oil than mandarin oil although it is quite rich in aliphatic aldehydes, particularly decanal. The oil of the cv. Malvasio has a composition which is between mandarin and sweet orange oils. The oil of cv. Comun is the only one fou...

Influence of Soil Salinity on Sensory Characteristics and Volatile Aroma Compounds of Nero d'Avola Wine

The influence of soil salinity on the chemical composition, volatile aromatic compounds, and sensory characteristics of Nero d’Avola wine was examined. Data on vineyard productivity, such as grape yield, are also reported. Physicochemical parameters were determined on the samples analyzed. Solid-phase microextraction was used for the extraction of aromatic volatile compounds, followed by capillary gas chromatography-mass spectrometry. Sensory analyses were performed by visual inspection, smelling, and tasting. Statistical analysis showed that most of the physicochemical parameters and volatile constituents, both primary and fermentation aromas, were influenced by the soil salinity. The composition differences observed among the samples had little influence on the sensory characteristics; the increase in soil salinity enhanced color intensity, purple reflexes, salty, citrus, and fruit in the aroma. Results indicate that Nero d’Avola vine may be well suited to increased soil salinity, even given reduced plant productivity.

On the Genuineness of Citrus Essential Oils. Part LII. Chemical Characterization of Essential Oil of three Cultivars of Citrus clementine Hort.

The composition of Citrus clementine Hort. essential oil, laboratory-prepared from fruits of different cultivars, has been studied. The following cultivars were examined: Comune, Oroval and Monreal. The volatile fraction was analysed by HRGC and HRGC–MS (quadrupole); 69 components were identified. The composition as single components and as classes of substances for each sample and the average composition for each cultivar are reported. The enantiomeric distribution of linalol was studied by HRGC with β-cyclodextrin columns. Polymethoxylated flavones, present in the non-volatile residue, were analysed by normal phase HPLC. Six components were identified: tangeretin, 3,3′,4′,5,6,7,8-heptamethoxyflavone, nobiletin, tetra-O-methylscutellarein, sinensetin and 3,3′,4′,5,6,7-hexamethoxyflavone. Clementine oil composition was then compared with that of Italian sweet orange and mandarin oil.

Migration of mineral oil from party plates of recycled paperboard into foods: 1. Is recycled paperboard fit for the purpose? 2. Adequate testing procedure

Party plates made of recycled paperboard with a polyolefin film on the food contact surface (more often polypropylene than polyethylene) were tested for migration of mineral oil into various foods applying reasonable worst case conditions. The worst case was identified as a slice of fried meat placed onto the plate while hot and allowed to cool for 1 h. As it caused the acceptable daily intake (ADI) specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) to be exceeded, it is concluded that recycled paperboard is generally acceptable for party plates only when separated from the food by a functional barrier. Migration data obtained with oil as simulant at 70°C was compared to the migration into foods. A contact time of 30 min was found to reasonably cover the worst case determined in food.

Uruguayan essential oils. Part X. Composition of the oil of Citrus clementine Hort.

The composition of the essential oil of Uruguayan Citrus clementine Hort., prepared in the laboratory from the fruit of Nules and Comune cultivars, has been studied. The volatile fraction was analysed by HRGC and HRGC–MS (quadrupole); 69 components were identified; the enantiomeric distribution of β-pinene, sabinene, limonene, linalol and α-terpineol was studied by multidimensional HRGC–HRGC. Polymethoxylated flavones present in the non-volatile residue were analysed by normal-phase HPLC. The results were compared with those of Italian clementine oil.

Uruguayan essential oils. Part VI. Composition of lemon oil

The composition of 31 genuine Uruguayan lemon oils obtained by industrial processing (FMC on line) during the 1995 season is reported. The samples were representative of all production areas situated in the North and South of Uruguay. The volatile fraction was analysed by HRGC‐FID and GC‐MS; the enantiomeric distribution of b-pinene, sabinene, limonene, linalol, terpinen-4-ol and a-terpineol was studied by multidimensional HRGC‐ HRGC; coumarins and psoralens present in the non-volatile residue were analysed by normal phase HPLC. The results relative to the volatile fraction were compared with those obtained for Uruguayan oils produced in the 1992 and 1993 seasons and for Italian FMC oils. Coumarins and psoralens have been analysed for the first time in Uruguayan oils; their content is compared with that of Italian oils. #1997 by John Wiley & Sons, Ltd.

On the Genuineness of Citrus Essential Oils. Part XLVIII. The Composition of Volatile Fraction of Some Varieties of Sweet Orange Oils

ABSTRACT The composition of the volatile fraction of 164 Italian sweet orange oils, laboratory-prepared from fruits of different cultivars, has been studied by GC and GC/MS. The following cultivars have been examined: Biondo comune, Navelina, Washington navel, Ovale, Valencia late (blond cultivars) Tarocco, Moro, Sanguinello (blood cultivars). The average composition of each of the cultivars is reported as is the standard deviation for each compound. As a result, the behavior of the classes of substances and of some of the components during the period analyzed are shown. Furthermore, the results are compared with those of previously analyzed commercial sweet orange oils.

Effects of cluster thinning on wine quality of Syrah cultivar (Vitis vinifera L.)

Cluster thinning is a viticulture tool used to correct overcropping, to improve fruit composition, and to find a balance between shoot growth and berry development. The main purpose of this study was to evaluate the effects of cluster thinning on the wine quality of Syrah cultivar under Mediterranean climate. Particular attention has been given to the volatile aroma compounds which are determinant for the sensory quality of the wine. Manual cluster thinning in the early stage of veraison was applied and compared with a not thinned control. Cluster thinning influenced yield reduction, advanced grape maturity, improved the phenolic content of grapes and therefore of wine, and influenced the volatile profile of wine. The grapes of thinned plants tend to get rich in varietal and fermentation aromas. Despite the economic impact, cluster thinning is a viable option due to the improvement in wine quality, especially for increasing the amount of compounds responsible for the typical aroma and color, at least in the Mediterranean climate where the search was carried out.