Apple

Apples represent an important produce available year around for European markets. This is possible owing to the different ripening periods in the northern and southern hemispheres as well as to excellent apple storability and sophisticated storage conditions. Only a small percentage of apple fruit production is marketed fresh; most of the produce is kept in cold storage in order to keep fruit commercially available for an extended period. Storage conditions appear to be an important factor that affects apple fruit quality. Interestingly, apples stored under cold storage showed higher levels of consumer acceptability than fruit stored under controlled atmospheres after short term cold storage. The attractiveness of fruit to consumers is determined by visual attributes that includes appearance, size, uniformity, color, and freshness, as well as non-visual attributes such as taste, aroma, flavour, firmness (texture) nutritional and health valueTaking this into consideration, the fruit industry set quality standards based in the instrumental texture measurements and on other physicochemical parameters such as total soluble solids and/or titratable acidity. Apples are an excellent reservoir of various nutrients, including vitamin C and soluble fiber, and they also contain a number of polyphenols. The most representative polyphenols present in apples are hydroxycinnamic acids, flavonols, procyanidins, flavonols and dihydrochalcones, while anthocyanins are present mainly in the apple peel. Apple polyphenols have been correlated with health-promoting properties, resulting in the old saying ‘An apple a day keeps the doctor away’. The polyphenolic content and composition varies greatly and are affected by genotype, geographic origin, other environmental factors, farming practices, maturity stage and postharvest treatments. To date, some preliminary experiments with native Cypriot cultivars have been carried out in our laboratory (Plant Sciences, Department of Agricultural Sciences, Biotechnology and Food Science). The aim of this project is to build a database for qualitative attributes and phytochemical profile of indigenous apple cultivars with the employment of state-of-the art techniques. The effect of cold storage regimes in apple postharvest performance will be also determined.

The project entitled “Postharvest performance, phytochemical profile and antioxidant potency of indigenous (Malus domestica) apple cultivars” was funded by the Research Promotion Foundation under the Call: Cyprus-Slovenia bilateral cooperation. ‘Kathista’ and ‘Lortiko’ are regarded as traditional and highly appreciated apple cultivars in Cyprus, yet their postharvest performance and phytochemical content are largely unknown. Such fruit were examined for their qualitative traits, phenolic composition and antioxidant capacity after harvest or short, intermediate or extended cold storage and additional ripening at room temperature (RT), using ‘Gala’ as reference cultivar. Total phenolic content was dependent on cultivar and length of cold storage, while hydroxycinnamic acids were always at higher levels compared to total flavonols for all the examined cultivars. No clear trends regarding the influence of cold storage or RT maintenance on fruit antioxidant properties were evident. Overall, quality attributes and polyphenolic content of the traditional apple cultivars were comparable with ‘Gala’ at harvest; thus they can be considered a good source of nutraceuticals as summer apple cultivars. However, extended cold storage deteriorates fruit performance and antioxidant capacity, particularly in ‘Lortiko’ fruit.