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Effect of certain bentonite products on the temporal variation of elemental content in white wine
15-21.Views:14The 'terroir' character of wines can be shaped with certain technological elements such as bentonite fining. Bentonite is an agent used for the removal of thermolabile proteins in wines. However, during fining, the quantity of certain wine components can change, including the elemental composition of the wine. According to the recommendations of bentonite suppliers, wines should be racked off the bentonite fining sediment within 2-3 weeks. However, in winemaking practice, wines can remain on bentonite fining sediment for up to 1-4 months. One reason for this is that racking wines off the sediment has a negative impact on wine quality. Thus, it is a question of how much the later or earlier racking time can alter the elemental content of the wine. Our study aimed to examine the elemental content of wines treated with three different bentonite products sampled from over the bentonite fining sediment at various time points. Our investigation was conducted with the 2019 vintage white wine of the University of Debrecen. Fining was performed with three bentonite products: Nucleobent, BW200, and Granubent Poretec. The sampling schedule following fining was: 0 days - unfined control, 7th, 14th, 27th, 56th, and 85th days. The macro-, meso-, and microelement contents (P, K, Ca, Mg, S, Al, Na, B, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd, Ba, and Pb) of the wines were determined using ICP OES and ICP MS devices. Our results showed significant changes in the Al, Na, Cr, Fe, Co, Ni, Sr, Ba, Cu, and Pb contents of the wines depending on the sampling time. It is noteworthy that all three bentonite products increased the Al and Pb contents of the wines. For Fe, dynamic increases were observed over time with the BW200 product, reaching the threshold value of susceptibility to brakeage. However, from a winemaking technology perspective, it was favorable for the Cu content of the wines to decrease with both earlier and later racking times, for all bentonite products examined. Based on the elemental analyzes of the white wines studied, it can be concluded that racking of wines should be timed according to the recommendations of suppliers.
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Historical background and constraints of a grapevine germplasm foundation in Hajdú-Bihar county, Eastern Hungary
11-17.Views:423The historical background of Debrecen linked to viticulture and wine-making stands mainly on the lack of drinkable water, the necessity of drinkable liquid during wartime and epidemics. The special character of the city evolved together with the changing lives of citizens and the increasing trade importance of the city. Period of Turkish occupation gave impetus to the formation of the 11 vine gardens of the settlement. After the devastation of rootmite and peronospora ‘Kadarica’ and ‘Nagy burgundy’ (‘Blaufrankish’), in smaller proportion - on lower sites – ‘Cabernet’ were planted. As white varieties ‘Ezerjó’, ‘Olasz Rizling’, ‘Kövidinka’, ‘white Mustos’, in smaller proportion ‘Szlankamenka’, ‘Erdei’, ‘Szilvaner’, ‘Mézesfehér’, ‘Bakar’, ‘Veltelini’ (red), ‘Fehér burgundi’ (? white burdunder), ‘Rajnai rizling’, ‘Red Tramini’, ‘Furmint’, ‘Muscat Lunel’, ‘Járdovány’ and ‘Juh-fark’ were planted. After the Trianon treaty in 1920, 2/3rd of Hungary was cut away. Érmellék wine region was also cut in two, thus Debrecen broke away from its wine region. Legal regulations after the World War II. (1959) referred back to variety application advised in 1924 for “place suitable for good wine production, not included in any wine region”, like Debrecen listing ’Ezerjó’, ’Mézesfehér’, ’Olaszrizling’, ’Bánáti rizling’, ’Furmint’, ’Hárslevelű’, ’Kövidinka’, Kecskemét virága’, ’Piros szlankamenka’,’Pozsonyi fehér’; ’Kadarka’, ’Oportó’ and ’Kékfrankos’ (Blaufrankish). The political changes of 1990 and Hungary’s admission to the Eurepoean Union almost annihilated the wine production of Debrecen. However little gardens conserved historic varieties which could date back even to many centuries. Through a local magazine a collecting work was announced pointing to gather ancient local (Vitis vinifera conv. pontica) varieties forming a genebank, established on the experimental station of the University of Debrecen. In 2014, about 112 items were collected (accessions). As a 2nd round of the work, with a more detailed and precise work, further 81 items were put into the reservatum. The latter represent single stuck collection, whereas the first ones are to be studied az mixed items. Most notable accession names (ACENAME) of the work are: ‘Fehér gohér’, ‘Veres gohér’, ‘Fekete gohér’, ‘Kék gohér’, ‘Erdei’, ‘Ezerjó’, ‘Kűbeli’, ‘Rizling’, ‘Mézes fehér’, ‘Dinka’, ‘Madling’, ‘Bakator’ and ‘Kadarka’. Simulteneously with the strenghening and morphological description of conserved stucks genetic identification of the items is being elaborated. Database comprising FAO/IPGRI multi-crop passport descriptors and OIV Primary descriptor priority list are to be published on-line in between the development of the platform.
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Water consumption of the wine grape varieties Kövidinka K.8 and White Riesling B.7
25-30.Views:231In the Carpathian Basin Kövidinka and White Riesling are promising wine grape varieties. As in the region continental climate dominates and dry years are not uncommon it was natural to study the water requirement and consumption of the two varieties. Morphological characters affecting transpiration were observed including leaf area, hairiness, number and type of stomata. The amount of water transpired per unit leaf area and time and rate of water consumption were measured in a model trial in cuttings with known water supply.
The water consumption of vine cuttings depends on varieties and is determined by the genotype but it is also affected by environment. Kövidinka requires little water and uses it to its advantage White Riesling requires more water and uses it rather lavishly. The results of our model trial could be introduced directly into viticulture practice.
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Maceration affects mineral composition and pH of wines
25-29.Views:456Mineral composition of wines is affected by many ecological and technological factors. These variables are mostly discussed focusing on certification of origin and human health. This paper gives data on possible changes in mineral composition and pH of wines due to 4 hours skin maceration (1st trial) and fermentation sur marc (2nd trial). Experimental site is situated on acidic sandy soil in middle east Hungary. The variety collection was established in 2003 with own rooted planting material in 3x1 m spacing, trained for single curtain training
system. Mineral composition of wines was determined with ThermoFischer Scientific iCAP 6300 ICP-OES, pH was measured with pH10pen (VWR International) in field, and with SevenEasyTM pH meter (Mettler Toledo) in laboratory. 1st trial with 9 PIWI white wine grape varieties pointed to demonstrate effects of skin maceration, which is abundantly used to elevate aroma content. 2nd trial with the use of ‘Medina’ red PIWI grape variety aimed to demonstrate effects of double pasta skin maceration in rose and red wine technology. Data of 1st trial show, that K, Cu, Mn and P respective increase with skin maceration, despite Fe show considerable decrease. Data of 2nd trial show, that K, Mg, Mn, P, Sr and B increase with longer skin contact and higher fermentation temperature, despite Fe and Ba decrease with this technology. In regard to pH, data show, that skin maceration and fermentation sur marc increase K content with about 30-70% respectively, withstanding that pH also increase with a considerable 0,4-0,5 value. K content can be higher in the end product, despite to earlier higher level of tartrate formation. An attention should be driven to lower level of tartaric acid and consequently higher pH characteristic for wines produced with the application of skin maceration or fermentation sur marc. -
Polyphenol- and anthocyanin content changes effected by different fermentation- pressing and aging technologies
65-67.Views:328Different grape processing, fermentation and aging technologies were compared in our study on the white wine-grape variety Grüner Veltliner between 2012 and 2014 in Hungary,Cserszegtomaj. The vines are grown on brown forest soil on dolomite bedrock, stocks were planted 3x1 m row and vine space, respectively in our experimental area. The soil has slightly alkaline pH, the orientation of the vine rows are East-West. The training system is modified Guyot cordon, with 1 m trunk height and cane pruning method. After the harvest half of the yield has been put into the de-stemmer crusher before pressing while the other half has been pressed immediately (whole bunches). From the filtered and bottled wine anthocyanin, and polyphenol content was measured in 2013 and 2014. Another enological technology testing experiment has been set on aging of Grüner Veltliner in 2013. The wine was fermented with addition of fine lees from juice sedimentation. Traditional (racking only), battonage and fast ready-made aging technologies have been set together, each treatment in three replicates were observed.
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Examinations of potential environmental friendly materials against tomato and pepper patogens
49-54.Views:347In organic farming systems the focus is on prevention with regards to plant protection. To follow the rules of Good Agricultural Practice one is able to avoid serious yield losses; if it is not possible the use of allowed materials are permitted. Organic farmers have less material to protect their plants so it is necessary to find effective potential materials. Bacterial and fungal diseases of tomato and pepper can cause serious losses in yield. Different materials were tested against some plant pathogen bacterial (Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas campestris pv. vesicatoria and fungal (Phytoptora infestans, Rhizoctonia solani, Sclerotinia sclerotium) strains in order to find potential materials in the field of organic seed treatment. In vitro trials have shown that vinegar, cider vinegar, red wine vinegar, white wine vinegar, cinnamon and thyme oil have inhibiting effect against the causative agent of bacteria and fungi. Germination test has shown that examined vinegar types do not decrease germination ability if the concentration is low, but in higher (more than 5%) concentration it ruins the germination ability. Even in 0,5% concentration of red — and white vine vinegar have good effect on germination capacity.
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Effect of different treatments to bacterial canker (Clavibacter michiganensis subsp. michiganensis), bacterial speck (Pseudomonas syringae pv. tomato) in tomato, and bacterial spot (Xanthomonas campestris pv. vesicatoria) in pepper
49-53.Views:630In ecological farming systems farmers can't use chemicals against pests. In ecological plant protection the aim is to prevent diseases; if it is not possible the use of allowed materials are permitted. Until now there haven't been enough effective and environmental friendly materials for seed treatment in organic farming. Seed borne diseases of tomato and pepper can cause serious losses in yield, so finding appropriate inhibitors has a great importance. Different materials were tested against these bacterial strains for seed treatment in this study. In vitro trials have shown that vinegar, cider vinegar, red wine vinegar and white wine vinegar have inhibiting effect against the causative agent of bacterial canker (Clavibacter michiganensis subsp. michiganensis), bacterial speck (Pseudomonas syringae pv. tomato) of tomato. These materials also have inhibiting impact on the causative agent of bacterial spot of pepper (Xanthomonas campestris pv. vesicatoria). Seed treatment with (natural alkaline material) sodium hydrogen carbonate (NaHCO3) had no effect on the examined bacterial strains. Among examined essential oils cinnamon oil seemed to be the most effective, but all oils decreased the germination ability. Thyme and savory teas were effective against Pseudomonas syringae pv. tomato. Other examined materials had insufficient bactericide impact (sucrose, NaCI, ethanol, valerian extract, peppermint tea). The germination test has shown that examined vinegar types don't decrease germination ability.
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Investigation of the Antioxidant Effect of Hungarian White Wines and Tokaj Wine Specialities
22-26.Views:484Authors investigated the antioxidant effect of wine-phenolics, expressed as total antioxidant status (TAS-value). This property may play an important role in elimination of the harmful effects of free radicals in human body.
Independently of their polyphenol composition, special quality Tokaj wines did not show extremely high TAS-values. In Tokaj Aszu wines the total antioxidant status was independent of the "puttony" number but was influenced by the length of aging time.
