scholarly journals Study on the yeast and mould biota of the botrytized grapes in Tokaj region in two years

Author(s):  
Zs. Bene ◽  
I. Magyar

The famous wine Tokaji Aszú is produced from "noble rotted" grapes infected and modified by Botrytis cinerea under special condition. The objective of this study was quantitative and qualitative characterisation of saprophytic fungi present on the surface of aszú­berries, with special regard to yeasts. There were considerable differences in these populations depending on the origin of noble rotted berries, notably between berries taken from the vine or the ones taken from the winery. Beside Botrytis, other mould species like Penicillium, Aspergillus were commonly found, in widely varying population. Yeast counts were detected between 104 and 107 cfu/g berry. In the samples taken from the vineyard Candida pulcherrima predominated followed by some aerobic basidiomycetous species, but Hanseniaspora species were also present in relatively high population. After transport and storage of the grape in the wineries, population of aerobic yeasts and C. pulcherrima quickly declined and Candida stellata followed by other sugar tolerant species became dominant. This autoselection process directs attention to the importance of storage conditions.

1998 ◽  
Vol 61 (10) ◽  
pp. 1352-1357 ◽  
Author(s):  
G. NTIRAMPEMBA ◽  
B. E. LANGLOIS ◽  
D. D. ARCHBOLD ◽  
T. R. HAMILTON-KEMP ◽  
M. M. BARTH

Aerobic, microaerophilic, coliform, and mold populations of Botrytis cinerea -inoculated strawberry fruit not exposed (control) or exposed to low and high quantities of four volatile compounds during storage at 2°C were determined after storage for 7 days and after removal of the volatile and transfer to 22°C for 3 days. Fruit harvested at the ripe stage were inoculated with 106 conidia B. cinerea per ml and were placed in plastic containers containing no volatile compound (control) or two quantities of (E)-2-hexenal (10 or 100 μl), (E)-2-hexenal diethyl acetal (30 or 300 μl), benzaldehyde (30 or 300 μl), or methyl benzoate (12 or 60 μl). The fruit containers were overwrapped with a low-density polyethylene film, sealed, stored at 2°C for 7 days, and then transferred to 22°C for 3 days. Aerobic, microaerophilic, and coliform populations of fruit exposed to volatile compounds tended to be lower than the Controls after storage at 2°C for 7 days and, depending on the volatile compound, similar, lower, or higher than the Controls after transfer and storage at 22°C. However, due to variability in initial aerobic, microaerophilic, and coliform populations of the fruit used in the different trials (P < 0.05), none of the differences between control and treatment and between treatments within a sample time were significant (P > 0.05). Strawberry fruit exposed to 100 μl of (E)-2-hexenal was the only treatment that did not show a significant increase in mold populations after transfer and storage at 22°C for 3 days. Additional studies are needed to determine if (E)-2-hexenal can be used in combination with other postharvest storage conditions, such as low temperature and controlled/modified atmosphere, to delay mold spoilage and extend the shelf life of the strawberry.


Author(s):  
O. A. Zadorozhna ◽  
T. P. Shyianova ◽  
M.Yu. Skorokhodov

Seed longevity of 76 spring barley gene pool samples (Hordeum vulgare L. subsp. distichon, convar. distichon: 56 nutans Schubl., two deficience (Steud.) Koern., two erectum Rode ex Shuebl., two medicum Koern.; convar. nudum (L.) A.Trof.: one nudum L. та subsp. vulgare: convar. vulgare: nine pallidum Ser., three rikotense Regel.; convar. coeleste (L.) A.Trof.: one coeleste (L.) A.Trof.) from 26 countries, 11 years and four places of reproduction was analyzed. Seeds with 5–8% moisture content were stored in chamber with unregulated and 4oC temperature. The possibility of seed storage under these conditions for at least 10 years without significant changes in germination has been established. The importance of meteorological conditions in the formation and ripening of seeds for their longevity is confirmed. The relationship between the decrease of barley seeds longevity and storage conditions, amount of rainfall, temperature regime during the growing season of plants is discussed.


2000 ◽  
Vol 65 (7) ◽  
pp. 1073-1081 ◽  
Author(s):  
Valerie Holubová ◽  
Iva Chvílíčková ◽  
Vlastimil Kubáň

Extraction procedures (steam distillation, supercritical fluid extraction and solvent extraction) for isolation of monoterpene hydrocarbons from fresh needles of Picea abies and Picea omorica were optimised. The procedures were compared with the aim of minimizing consumption of needles and improving the extraction efficiency and repeatability. An influence of homogenisation procedures and storage conditions (liquid nitrogen, -18 and 4 °C) on the total content and composition of essential oils was studied. Cryogenic grinding (liquid nitrogen) combined with the extraction with cold hexane (extraction time 2 h) and subsequent GC-MS determination in freshly homogenised needles gives the best results (1.5-4 times better extraction efficiency, RSD < 10% for P. abies and < 25% for P. omorica). Limits of detections (3 S/N) for individual monoterpene hydrocarbons from units to tens of ng/g and recoveries 97.2-101.4% were found in fresh needles (calculated to fresh weight). While cooling to 4 °C is unacceptable, freezing at -18 °C for the period of 18 days in the dark gives also good results.


Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 374
Author(s):  
Teresa Szczęsna ◽  
Ewa Waś ◽  
Piotr Semkiw ◽  
Piotr Skubida ◽  
Katarzyna Jaśkiewicz ◽  
...  

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.


Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 83
Author(s):  
Supapohn Yamuangmorn ◽  
Suchada Jumrus ◽  
Sansanee Jamjod ◽  
Narit Yimyam ◽  
Chanakan Prom-u-Thai

Purple rice has become an interesting source of nutritional value among healthy cereal grains. The appropriate cultivation together with post-harvest management would directly benefit farmers and consumers. This study aimed (i) to determine the yield, grain nutritional quality, and antioxidant capacity of purple rice varieties grown at lowland and highland elevations, and (ii) to evaluate the effects of storage conditions on the stability of the rice nutritional value during six months of storage. The high anthocyanin PES variety grown in the lowlands had a higher grain yield than the plants grown in the highlands, but grain anthocyanin concentration had the opposite pattern. In the high antioxidant capacity KAK variety, grain yield and DPPH activity were not significantly different between plants grown at the two elevations. The storage of brown rice and vacuum-sealed packages were both found to preserve greater anthocyanin concentrations in PES, but there was no effect on the DPPH activity of KAK. The grain properties were not significantly different between storage at 4 °C and room temperature. This study suggests that the optimal cultivation practices and storage conditions would result in the higher yield and grain quality of purple rice varieties.


2021 ◽  
Vol 259 ◽  
pp. 117738
Author(s):  
Cathrina H. Edwards ◽  
Amalia S. Veerabahu ◽  
A. James Mason ◽  
Peter J. Butterworth ◽  
Peter R. Ellis

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