Researchers are investigating which characteristics of apples are key to creating the desired flavour of cider from Hardanger. Yeast, sugar and acid – they all work together.
In 2009, “Cider from Hardanger” became a protected geographic designation, like sparkling wine from Champagne. Since then, the cider industry has virtually exploded. Researchers now aim to professionalize the cider industry.
The apples we eat should be crunchy and fresh-tasting, suitably sweet and tart. Some of the same qualities are important for cider production, wherein sugar and acid are the key common denominators.
NIBIO has identified factors that affect the flavour of pressed apples, in both unfermented apple juice and fermented cider. Ripeness is highly important because sugar content plays a large role. The sugar is converted into alcohol in the fermentation process.
Apples that contain a lot of sugar produce the best flavour and result in a rich cider. As the fruit ripens, starch is broken down into sugar. The time of harvesting is therefore crucial to the end product.
During ripening, the sugar content increases while the acid content decreases. There must be a balance between sugar and acid. The combination of sugar and acid in Norwegian apples produces the special flavour that characterizes Cider from Hardanger and other Norwegian ciders.
Phenols, too, have a substantial influence on colour and flavour qualities. Too few phenols produce a bland flavor, while excessive phenols result in too much astringency and bitterness. Phenol content will vary from year to year based on weather, harvest time, ripeness and various forms of stress. In addition, the apple variety and methods of cultivation, storage and pressing will affect the flavour.
Together, these are ingredients that contribute to good cider, but more knowledge is needed about how they work together in order to ensure controlled production and a high-quality end product.