Sprečavanje razgradnje hlapljivih estera i terpena tijekom skladištenja vina i pripravka sličnog vinu dodatkom fenolnih ekstrakata

The effect of red wine phenolic extracts on the stability of wine volatile esters and terpenes was examined. Muscat (white) and Xinomavro (red) wines were enriched with each extract at 120 or 200 mg/L, and stored in open bottles at 20 °C for 3 and 2.5 days, respectively. Moreover, a model wine medium containing isoamyl acetate, ethyl hexanoate and linalool was enriched with each extract at 100 mg/L, and stored in sealed bottles at 20 °C for 45–90 days. All samples were analysed for volatiles using SPME along with GC-MS analysis. Phenolic composition of wine extracts was determined using HPLC-DAD. No effect on the concentration of any volatiles was observed as a result of the addition of each extract in each wine or the model medium. A wine extract rich in phenolic acids and another one rich in anthocyanins and flavanols inhibited the decrease of volatile esters and terpenes in one or both wines and the model medium. Among them were several important for the aroma of wine such as ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate and linalool. The results presented here indicate that wine phenolic acids, and anthocyanins or flavanols may be taken into account as potent inhibitors of the disappearance of volatile esters and terpenes in wines.Istražen je utjecaj fenolnih ekstrakata crnog vina na stabilnost hlapljivih estera i terpena u vinu. Muškat (bijelo vino) i Xinomavro (crno vino) obogaćeni su s po 120 ili 200 mg/L ekstrakta i skladišteni u otvorenim bocama tijekom 3 odnosno 2,5 dana pri 20 °C. Pripravak sličan vinu, koji sadrži izoamilacetat, etilheksanoat i linalol, također je obogaćen s 100 mg/L fenolnog ekstrakta, te skladišten u zatvorenim bocama pri 20 °C tijekom 45-90 dana. Hlapljive komponente svih uzoraka analizirane su SPME i GC-MS analizom. Fenolni sastav vinskih ekstrakata određen je HPLC-DAD metodom. Dodatkom fenolnih ekstrakata nije zabilježena promjena koncentracije hlapljivih sastojaka u vinima i pripravku sličnom vinu. Vinski ekstrakt bogat fenolnim kiselinama i drugi bogat antocijanima i flavanolom smanjili su razgradnju hlapljivih estera i terpena u vinu i pripravku, prije svega spojeva važnih za aromu vina, kao što su etilacetat, izoamilacetat, etilheksanoat, etiloktanoat, etildekanoat i linalol. Rezultati pokazuju da bi se fenolne kiseline, antocijanini i flavanoli iz vina mogli upotrijebiti za inhibiciju razgradnje hlapljivih estera i terpena tijekom skladištenja vina

Scavenging Capacities of Some Wines and Wine Phenolic Extracts

The aim of this study was to assess the ability of different wines – a sweet red, a dry red, a sweet white, and a dry white – to scavenge the stable 1,1’-diphenyl-2-picryl-hydrazyl radical (DPPH.) and to determine their phenolic composition. Both red wines contained, apart from anthocyanins, also higher concentration of total phenolics, tartaric esters, and flavonols than the two white wines. All wines exhibited scavenging activity analogous to their total phenolic content. However, their phenolics differed in antiradical potency, which was visible in their EC50 values. The dry red wine, Xinomavro, had a lower EC50 value, indicating the higher antiradical potency of its phenolics. The scavenging capacities of phenolic extracts from Xinomavro red wine on hydroxyl radicals, superoxide radicals, and singlet oxygen were also assessed. Wine total extract was fractionated by extraction, and each of the three fractions was then subfractionated by column chromatography into two subfractions. Wine total extract, and its fractions and subfractions exhibited scavenging capacity on hydroxyl radicals, superoxide radicals, and singlet oxygen, indicating the activity of many wine phenolics. The most active wine extracts towards hydroxyl radicals were characterized by the high peaks of flavanols, anthocyanins and flavonols in their HPLC-DAD chromatograms. The most active extract towards superoxide radicals was rich in flavanols and anthocyanins. The characteristic phenolics of the most active wine extracts towards singlet oxygen were flavanols, flavonols and phenolic acids. The ability of all red wine phenolic extracts to scavenge singlet oxygen, along with hydroxyl and superoxide radicals, emphasizes its health functionality

Inhibition of the Decrease of Linalool in Muscat Wine by Phenolic Acids

Two white wine extracts rich in phenolic acids, caffeic acid and gallic acid were tested as inhibitors of the decrease of linalool in Muscat wine. Each wine extract was added at 60 ppm and each phenolic acid at 40 ppm. Immediately after the addition of each wine extract or phenolic acid, no effect on the concentration of linalool was observed, but it decreased from the initial 470.9 to 223.3 μg/L after storage in open bottles at 20 °C for 4 days. Its decrease was significantly inhibited by each wine extract or phenolic acid

Potential Antimicrobial Activity of Red and White Wine Phenolic Extracts against Strains of Staphylococcus aureus, Escherichia coli and Candida albicans

The aim of this study was to assess antimicrobial activities of wine phenolic extracts. The potential antimicrobial activity of alcohol-free red and white wine extracts against pathogenic strains of Staphylococcus aureus, Escherichia coli and Candida albicans was studied using the agar well diffusion method. Total phenolic content of wine extracts was determined by the Folin-Ciocalteu method, while their phenolic composition was specified by high performance liquid chromatography and diode array detector (HPLC-DAD). The antimicrobial activity of the tested extracts was related to their total phenolic content. Antimicrobial activity of the tested wine extracts was more effective against S. aureus and less effective against E. coli and C. albicans. Also, C. albicans was resistant to more wine extracts than the two bacterial species studied. The antimicrobial activity and the phenolic composition of the tested white and red wine extracts indicate that some phenolic acids have the potential to inhibit growth of certain pathogens such as S. aureus, E. coli and C. albicans strains

Sensitivity of Seed Germination to Salt Stress in Teff [Eragrostis tef (Zucc.) Trotter]

Teff is an annual grass originated in Ethiopia, grown for both human food and animal feed. Salinity and moisture stress are the main limiting factors of agricultural development on arid and semi-arid regions. The aim of this study was to investigate the effect of salinity due to NaCl on germination of teff. A set of experiments was conducted under a completely randomized design with four replications of 200 seeds at two different suboptimal germination temperatures (15 and 25 °C) in the dark for 10 days. In order to create salt stress conditions during the germination process, seven solutions were used (0 as control, 80, 160, 240 and 320, 400 and 480 mM NaCl). The germination performance was evaluated by final germination percentage and mean germination time. The presence of NaCl reduced germination, especially above 240 mM for 15 °C and 400 mM for 25 °C. The mean germination time increased with higher NaCl levels

A Comparison of Cost in Organic and Conventional Olive Oil Production in Greece

An economic analysis of conventional and organic olive oil cultivation was examined in one of the most important olive-growing regions in Greece. Based on structured interviews and open-ended questions of 60 farmers from both organic and conventional systems, this study aimed to clarify the cost and returns of organic olive oil cultivation in comparison with conventional farming. Olive oil cultivation cost was calculated as 2.60 € kg-1 in organic and 2.25 € kg-1 in conventional system. The selling price for organic olive production was 4.19 € kg-1 compared to 3.63 € kg-1 for conventional production. Net profit from organic olive oil cultivation was 7,043.43 € ha-1, which was 3,664.58 € ha-1 higher than the net profit from conventional cultivation. Finally, in both types of olive farming the results of financial analysis attested to a positive convenience; however, organic farming is more advantageous providing a financially competitive alternative to conventional

Scavenging Capacities of Some Wines and Wine Phenolic Extracts

The aim of this study was to assess the ability of different wines – a sweet red, a dry red, a sweet white, and a dry white – to scavenge the stable 1,1’-diphenyl-2-picryl-hydrazyl radical (DPPH.) and to determine their phenolic composition. Both red wines contained, apart from anthocyanins, also higher concentration of total phenolics, tartaric esters, and flavonols than the two white wines. All wines exhibited scavenging activity analogous to their total phenolic content. However, their phenolics differed in antiradical potency, which was visible in their EC50 values. The dry red wine, Xinomavro, had a lower EC50 value, indicating the higher antiradical potency of its phenolics. The scavenging capacities of phenolic extracts from Xinomavro red wine on hydroxyl radicals, superoxide radicals, and singlet oxygen were also assessed. Wine total extract was fractionated by extraction, and each of the three fractions was then subfractionated by column chromatography into two subfractions. Wine total extract, and its fractions and subfractions exhibited scavenging capacity on hydroxyl radicals, superoxide radicals, and singlet oxygen, indicating the activity of many wine phenolics. The most active wine extracts towards hydroxyl radicals were characterized by the high peaks of flavanols, anthocyanins and flavonols in their HPLC-DAD chromatograms. The most active extract towards superoxide radicals was rich in flavanols and anthocyanins. The characteristic phenolics of the most active wine extracts towards singlet oxygen were flavanols, flavonols and phenolic acids. The ability of all red wine phenolic extracts to scavenge singlet oxygen, along with hydroxyl and superoxide radicals, emphasizes its health functionality

Sensitivity of Seed Germination to Salt Stress in Black Cumin (Nigella sativa L.)

Black cumin is an annual oilseed crop, native to the Mediterranean region and widely used for nutritional and medicinal purposes. Reduced seed germination and early seedling growth under saline conditions are considered as major factors limiting the establishment of crops. The objective of this study was to investigate the effect of salinity due to NaCl on germination of black cumin seeds. A set of experiments was conducted under completely randomized design with four replications of 200 seeds at two different suboptimal germination temperatures (15 and 20 °C) in the dark for 16 days. In order to create salt stress conditions during the germination process, five solutions were used (0 as control, 80, 160, 240 and 320 mM NaCl). The germination performance was evaluated by final germination percentage and mean germination time. The effect of salinity on seed germination percentage and mean germination time was significant at p<0.01. Germination of the controls was 96% and 95% at 15 °C and 20 °C, respectively. The presence of NaCl, regardless of temperature, reduced germination. This reduction was more severe at 15 °C (15%, and 19% germination in cases of 80 and 160 mM concentration respectively) than at 20 °C (65% at 80 mM salinity level) and no germination was observed from 240 mM onwards. The mean germination time increased with increased NaCl levels, especially at the lower temperature of 15 °C. The overall results of this experiment showed the inhibitory effects of salt stress on seed germination parameters of black cumin

Comparative Technical and Economic Analysis of Organic and Conventional Soybean Production in Greece

Soybean is considered to be an alternative crop and its cultivation could offer an innovative and high-quality product. A case study was implemented on an existing farm to examine the prospects of soybean production in Greece and to evaluate the economic outcomes of the crop cultivation under organic and conventional cropping system. The economic analysis showed that the cost of conventional soybean production was 0.37 €/kg, while the cost of organic soybeans was 0.50 €/kg. The organic and conventional soybean selling prices were 0.6 and 0.4 €/kg, respectively. In addition, the financial performance of the farm improved after the introduction of organic soybean crop, where the net profit increased by 26.3% compared to the initial profit of the farm, while the increase in the conventional was less at 10%. Soybean is a relatively new crop in Greece with high net profit, especially under organic cultivation mainly due to lower inflow of external imports

Organic Agriculture and Innovative Crops under Mediterranean Conditions

Climate change is the greatest environmental threat facing humanity worldwide. Areas of South-East Europe and Mediterranean basin are expected to be among the most vulnerable countries to climate change. As a result of climate change, new species and crops have been introduced and may be introduced in the coming years. In addition, FAO considers that Organic Agriculture is an effective mitigation strategy to climate change and can build robust soils that adapt better to weather extremes associated with climate change. This review provides an overview of the growth performance of new innovative crops, including chia, camelina, quinoa, teff and nigella and retrovative crops such as flax and emmer wheat, based on experimental investigations conducted under Mediterranean conditions and organic cropping system. Several studies, performed under organic system, have proved that innovative crops can also be grown for alternative uses. Quinoa and chia could be successfully used in animal feed. Moreover, quinoa could be exploited as a medicinal plant due to saponins extracted from seed coats. Nigella and camelina seeds contain oils which can have several uses in pharmaceutical and food industries. Flax seed oil is rich in omega-3 fatty acids and can be accepted in the diets designed for specific health benefits. According to the literature, it is observed that innovative crops cultivated under organic system present better quality and similar yields as with those cultivated under conventional system, and in some cases, even higher. Taking all these into account, organic agriculture could also be characterized as innovative and not only as traditional