In Poland export of fresh and frozen strawberries to UE countries plays an important role in the state economy. To increase competiveness of Polish strawberries vs Moroccan, Chineese and Spanish ones, there is a need of introducing new table cultivars to cultivation. The aim of the study was to determine chosen chemical parametres of fresh and frozen fruit of ‘Pandora’, ‘Elsanta’, ‘Senga Sengana’, ‘Tarda Vicoda’ , ‘Marmolada’ (‘Onebor’) and ‘Kent’ cultivars. The strawberries were grown on plantation situated near to Szczecin in the 1999 and 2000 seasons. The two-year observation showed no statistically significant differences between cultivars as far as mean soluble solids and dry weight content of fruits was concerned. During lowtemperature storage statistically significant decrease of vitamin C and saccharose was found. Fresh strawberry fruit had significantly higher content of these constituents than frozen ones after 4 and 8 months of cold storage.
Blueberries are tasteful fruits and are widely believed to be the source of health beneficial compounds, especially phenolics. Freezing is one of the methods of prolonging their supply beyond vegetative season. The aim of the study was to estimate fruit chemical composition of four blueberry cultivars (‘Spartan’, ‘Bluecrop’, ‘Jersey’ and ‘Blueray’). Dry weight, total sugar, total acidity, vitamin C and total polyphenol content were determined in fresh berries and after 6 and 12 months of freeze-storage at –25℃ . In generally, ‘Bluecrop’ berries showed the most stabile chemical composition (dry weight, total sugar, total acid content) whereas ‘Spartan’ ones the least. Considering the all storage period the least pronounced changes occurred in total acid content (increase by 0.1 g citric acid · 100g⁻¹) while the most substantial in vitamin C content, decrease by 57% (‘Bluecrop’) – 72% (‘Jersey’).
Przedmiotem badań było określenie zmian jakościowych w świeżych, zamrożonych i przechowywanych przez 6 i 12 miesięcy przecierach z truskawek odmiany ‘Elsanta’. Sporządzono 3 warianty homogenatów: bez cukru oraz z dodatkiem 5 i 10% cukru. Oznaczano w nich zawartość suchej masy, witaminy C i polifenoli ogółem oraz kwasowość ogólną. Ponadto w homogenatach świeżych i zamrożonych przez 2 dni, 6 i 12 miesięcy określono ogólną liczbę bakterii, drożdży i pleśni oraz miano coli i enterokoków. W czasie przechowywania zamrożonych homogenatów najmniejsze zmiany ilościowe zaobserwowano w zawartości suchej masy i kwasowości ogólnej a największe w zawartości witaminy C i polifenoli ogółem W procesie zamrażania cukier działał ochronnie na mikroorganizmy, dlatego w homogenatach z dodatkiem 5 i 10% cukru występowała większa liczba bakterii, drożdży i pleśni niż w przecierze niesłodzonym. Świeżo zamrożone homogenaty odznaczały się nadmierną w stosunku do wymagań, ilością pleśni i drożdży (tj. > 5,0x 102 jtk-g-1). Natomiast po 6 miesiącach przechowywania we wszystkich homogenatach nie stwierdzono obecności drożdży, pleśnie występowały nielicznie, a większa liczba bakterii (103 jtk-g-1) utrzymywała się jedynie w homogenatach z dodatkiem 10% cukru. Po 12 miesiącach składowania stan mikrobiologiczny wszystkich zamrożonych przecierów był do siebie zbliżony.
The spraying with titanium is one of the agronomic practices used to stimulate the flowering, bearing of fruit and production of strawberry plants. The aim of the study was to assess the influence of titanium treatment (Ti4+-ascorbate) on L-ascorbic acid, total polyphenol, antioxidant activity, and phenolics profile of six strawberry fruit cultivars. The experiment was carried out on a commercial plantation where basic fertilization and protection of plants followed the recommendations for the species. The chemical composition of strawberries, as a response to titanium treatment, was differential and cultivardependent. A significant increase of total polyphenol content was noted only in ‘Elkat’ berries. The treatment resulted in the increase of L-ascorbic acid in all the cultivars, except for ‘Kent’. However, the influence of Ti on the antioxidant activity of strawberries against ABTS (2,2’-azinobis-(3-ethylbenzothiazoline-6sulfonic acid) and DPPH (2-diphenyl- 1-picrylhydrazyl) radical was differential. Only in treated ‘Elsanta’ fruit a significant enhancement of scavenging both radicals was observed. Moreover, the treatment caused a significant increase of total anthocyanin content in ‘Kent’, ‘Selva’ and ‘Senga’ fruit, and a significant decrease of these compounds in ‘Dukat’ berries. Regarding total proanthocyanidins, the only significant change was a decline observed in treated ‘Elsanta’ berries. The applied treatment exerted no considerable effect on ellagic acid and p-coumaric acid content in any of cultivars tested
The influence of Na F (2, 33, 66, 330 ppm F) added with nutrient solution to the bedding(quartz sand)on magnesium and calcium content in pea, bean and maize shoots was examined At suitably high F concentration in the bedding the decrease of these two elements concentration (Ca in much greater degree then Mg) in tested plant tissues