Ingunn Øvsthus

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(+47) 482 07 250
ingunn.ovsthus@nibio.no

Sted
Ullensvang

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Ullensvangvegen 1005, 5781 Lofthus

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Sammendrag

Norwegian apple ciders have recently gained attention at the levels of international competitiveness. Accordingly, a comparative study on the chemical composition of selected Norwegian and French apple ciders was conducted to gain knowledge on what ubiquitous chemical parameters make the Norwegian ciders different from ciders from well-established producing regions. A total of 43 ciders, 24 Norwegian and 19 French, in the category of acidic dominant ciders, were included in the study. Ethanol, individual sugars and organic acids, pH, total phenols, aroma compounds including esters, C6-alcohols, volatile phenols and terpenoids, were analysed. Norwegian ciders showed higher contents in ethanol, malic and citric acids, whereas total phenols, pH, glucose, and fructose were higher in French counterparts. Regarding the aromatic profile, no significant differences were observed for C6-alcohols. In contrast, differences were more expressed in the case of esters and volatile phenols. Norwegian ciders were characterised by higher average concentration for all the groups of esters, with the most important differences measured for higher alcohol acetates. Norwegian ciders also displayed higher contents of 4-vinylphenol and 4-vinylguaiacol while French ciders contained substantially higher levels of 4-ethylphenol and 4-ethylguaiacol. These results are in mutual correlation with the empirical observation reporting Norwegian apple ciders as more acidic, alcoholic and with lighter body but fruitier profile. Whereas French ciders are often perceived with more structure and animalistic profile.

Sammendrag

https://ehc.usamv.ro/wp-content/uploads/2024/05/S10-Book-of-Abstracts.pdf The mid-early ripening cultivar, 'Summerred‘, is popular among consumers and widely grown in Norway. However, 'Summerred‘ fruit is prone to rapid softening and development of senescence-related disorders, especially senescent breakdown. Calcium can have a significant role in maintaining firmness and delaying senescence of fruits. In a two-year study, foliar application of calcium chloride (CaCl2) was conducted six times, with varying weather conditions between the growing seasons. Fruit was harvested at optimal commercial maturity and stored at 4 °C for either six or nine weeks, followed by simulated shelf-life conditions at 20 °C. Ethylene levels were monitored during storage to detect ripening discrepancies. At harvest, CaCl2-treated fruit exhibited significantly lower ethylene production compared to untreated fruit, although no differences were observed during the end of the storage period. Senescent breakdown showed significant variability between the two seasons, with an incidence of up to 15 % in the first season and nearly no incidence in the second season. Senescent breakdown increased with storage length but was not affected by foliar CaCl2 application. Real-time PCR analysis of fruit flesh samples revealed increased expression of polygalacturonase and β-galactosidases genes after storage, indicating their involvement in apple softening. Notably, there were no differences in gene expression between CaCl2-treated and untreated fruit after storage. Expression patterns of genes involved in ethylene biosynthesis at harvest were different between the two seasons. Higher expression was observed in the year when more disorder development occurred, indicating advanced maturity at harvest. There were no significant differences in Streif index between the two years.