Transformation through Fermentation
At Merridale Cider, we ferment the juice only once a year, at harvest time, so we must plan carefully. In commercial cideries, where they use concentrates, they can simply make more cider whenever they need it. Merridale makes all of its cider for the coming year when the fruit ripens. Therefore, from time to time, loyal drinkers have to wait until the next vintage is ready.
Only pure, first-pressed juices are used to make cider at Merridale, where the 22,000 and 26,000 litre (4,900 and 5,720 gallon) stainless-steel tanks are filled with raw juice and various yeasts. The primary fermentation tanks have the optimum shape for fermenting cider. In this anaerobic (without air) environment, the cider is allowed to ferment naturally and slowly to bring the flavours of the fruit out delicately. Rick has studied fermentation science related to cider, and he trusts that Mother Nature does the job the best. Other cidermakers, however, heat their juices or add chemicals to hasten or hinder the process.
Various yeasts and yeast nutrients are added to the raw juice, according to the recipe for the end product. Rick does careful testing to match the acidity and sugar levels of the juice, so that the finished products have guaranteed, consistent quality and characteristics.
It is time to move the cider after 6 to 12 weeks in the primary fermentation tanks, as the fermentation slows because the yeasts consume all the available sugar. The amount of time the cider is left to “rest on its lees” impacts the flavour of the final product. The “lees” are made up of dead yeast cells and apple solids, and the lees that are left behind at this stage are re-used in the brandy making or are composted on site.
When the time is right, the cider is siphoned out and redistributed into tanks ranging from 500 to 5000 gallons (2273 to 22,730 litres). These tanks are filled to the brim to assure that an oxygen-free environment is maintained, as cider will oxidize or turn to vinegar if the fermentation process is contaminated. The cider is left to rest as it continues to settle and mature slowly, which gently brings out its full body and flavour. This resting period can range from a few months for a Draft cider, or up to two full years for the Scrumpy or Cyser, depending on the temperature and other conditions.
Once the cider has matured, it must be cleared of the yeastly “must” that can cloud it. If the cider has not “fallen” sufficiency, then clarity can be achieved in several ways. Some cidermakers use chemicals or fining agents to clear their ciders, but true craft cidermakers do not. The cider products at Merridale Ciderworks are cleared using a fine filtering system.
Wines are usually filtered at ½ microns or less to ensure that no yeast cells remain, which means the wine will not continue to ferment in the bottle. Fermented apple juice has larger suspended solids that add color and flavour to the products, so Rick filters to only 1 micron; however, this leaves some yeast cells behind. Thus, Merridale Cider is still “living” when you take it home and open up the bottle.