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  • Optimization of sample preparation for determination of antioxidant parameters from one grape berry
    93-97.
    Views:
    370

    Berry quality is an important issue in wineprocessing, however evaluating characteristics in a single berry level is very complex. The Phenolic compound analysis is more challenging because of the limited amount of material and a mixture of skin, pulp and seed. No clear protocol exists for evaluating these compounds from single berries. The aim of our investigation was to develop such a protocol. Single whole grape berries samples were homogenized in 20 replicates by 5 different methods. The most effective method was when berry was placed in a mortar and was crushed with a pestle under liquid nitrogen until seeds were clearly visible. Seeds were then taken from the mortar and crushed between two stainless steel plates with a hammer, and returned to the mortar without residues. Homogenization continued until the sample had a powdery appearance. The homogenized samples were taken for further analysis such as total polyphenols, total anthocyanin contents and total antioxidant capacity. Our results demonstrate that single berries could be processed and that the homogenates were suitable for taking chemically uniform subsamples.

  • Climatic indicators regarding the rest period of sour cherry
    49-52.
    Views:
    528

    Sour cherry production in the world is increasing gradually. Profitable production, i.e. yield, depends largely on weather conditions. If Hungary wishes to keep up with the most successful countries, attention should be paid to the weather during the dormancy period, being definitely decisive from the points of view of quality as well as quantity. In order to predict the expected risk factors, characterisation of the most important weather parameters is necessary. For that purpose, the database of the Institute of Research and Extension Service for Fruit Growing at Újfehértó Ltd. has been utilised. Records of weather conditions were collected throughout the period 1984-2005, i.e. daily minimum, maximum and mean temperatures (°C), and phenological diary of sour cherry varieties ’Újfehértói fürtös’, ’Kántorjánosi’ and ’Debreceni bôtermô’. For the future expectations study we have used the RegCM3.1 regional climate model with 10 km resolution. Data of 4 indicators have been traced: Average temperatures, Number of days without frost, Maximum length of periods without frost, Maximum length of frosty period. On the one hand, we surveyed the changes; on the other hand, estimates have been attempted for the future changes expected during the following decades.

  • Yield and composition of supercritical fluid extracts of different Lamiaceae herbs
    79-82.
    Views:
    326

    In our work the effectiveness of supercritical carbon dioxide extraction was studied on volatile components of Lamiaceae herbs. The aim of our investigations was to determine the optimal extraction parameters yielding high amount of volatiles in a desirable composition. As plant materials, dried and powdered cude drugs of Thymus vulgaris, Thymus pannonicus, Satureja hortensis, Ocimum basilicum, Rosmarinus officnalis and Salvia officinalis were chosen. Pressure (8-30 MPa), temperature (35-60 °C) and time (5-60 min) of extraction were regulated. Results obtained by supercritical fluid extraction (SFE) were compared to that of the conventional extraction procedur, hydrodistillation (HD). In the case of Thymus vulgaris, Thymus pannonicus and Salvia officnalis, extract yield of SFE was comparable to the essential oil amount obtained by hydrodistillation from the same drug. Essential oil rich thyme extracts were analysed by GC-FID. We have found that yield and quality of SFE extracts highly depend on the conditions of extraction.

  • Evaluation of the vegetative and generative performance of new apple cultivars in the Nyírség region
    39-44.
    Views:
    397

    In this paper we examine apple varieties, which are planted expansively in the development apple orchards of the Western- European countries, but about its production characteristics we don’t have or just few practical experiences in Hungary. These varieties can be described with regular and high yields, aesthetic and alluring appearance in their origin places, what ensure profitable producing for the growers. Under the Hungarian climate which tends to be often extreme (hard cold winters, late spring frosts, summer drought, heat stress) these varieties may behave differently, so before the substantial planting it is expedient to carry out variety evaluations to avoid the later failures. The place of our experiments is located in the Nyírség representing adequately the ecological conditions of the surrounding areas, so the gained results can be adapted easily in the biggest apple production site of Hungary. Regarding the vegetative and the generative parameters of the 14 examined varieties (’Gala Venus Fengal’, ’Gala Decarli-Fendeca’, ’Galaval’, ’Jugala’, ’Gala Schnitzer (S) Schniga’, ’Red Cap Valtod (S)’, ’Early Red One’, ’Jeromine’, ’Crimson Crisp (Co-op 39)’, ’Red Topaz’, ’Wilton’s Red Jonaprince’, ’Red Idared’, ’Fuji September Wonder’, club cultivar) we found significant differences. The ratio of the thickness of trunk and the main branches showed that the trees have an optimal canopy structure in accordance with the Zahn principles, so they are in harmonious growing balance. The ‘Gala’ sport trained to slender spindle produced the highest yields, while the ‘Fuji’ and the ‘Red Delicious’ sport trained to super spindle can be described with the lowest values. All the cultivars reached the eating quality (65-70 mm), from which the ’Red Idared’, the ’Red Jonaprince’ and the ’Red Cap’ produced outstanding fruit size (81-85 mm).

  • Fruit Quality of Sweet Cherry Cultivars Grafted on Four Different Rootstocks
    59-62.
    Views:
    352

    A rootstock trial planted at the Szigetcsep experimental station in 1989 involved the study of two cultivars- `Germersdorfi FL 45' and 'Van' -grafted on four different rootstocks — 'Colt', `MxM 14 — Brokforest', `MxM 97 — Brokgrow' and 'Saint Lucie 64' as a control. The trees were trained to the "Modified Brunner-spindle" system and came into bearing in 1993. The yield per tree, fruit weight and fruit diameter have been measured each year since then. The refractivity, the acid content of the fruit juice, fruit cracking after four hours' dipping in water and stone weight ratio have also been measured since 1995. In 1997 and 1998 these parameters as well as fruit cracking after 24 hours' dipping were measured. Fruit firmness and fruit colour were also estimated. In almost every observed parameter significant differences were found between the scion cultivars. Yield efficiency was significantly higher on 'NUM 14' and 'Saint Lucie 64' than on the other two rootstocks. As regards fruit weight, in both cultivars and over an average of six years, it was found that trees on low yielding tree on 'Colt' rootstock had the highest fruit weight values and on heavy producing `MxM 14' the smallest. Soluble solids content was higher on 'Colt' and `MxM 97'. No significant differences between the rootstocks were found in acid content of the fruit juice. There were significant differences between the rootstocks in fruit cracking after 4 and 24 hours' dipping in water. Seemingly with respect to cultivars and rootstocks the year has a considerable effect on fruit cracking.

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