The different historic and classic methods used by some of our breweries to filter/lauter are extraordinary. Here we will examine two very unique tactics implanted by two cider producers, both wonderful and both quite different. They both are using natural mechanisms to solve problems during the brewing/fermentation/production process that will not destroy any flavor/aroma compounds in the liquid. Big producers tend to use chemicals or chemical processes to solve such issue, with tremendous impact on the survival of many flavor/aroma compounds.
Sandford Orchard is using an historic straw pressing method to filter their pomace juice. Numerous layers of straw, including wheat reed and barley straw, are built up with layers of pomace in between. A hydraulic press is used to push down on the straw pile to extract as much liquid from the pomace as possible. The straw serves the same functionality that the malt husk does in lautering (beer) wort.
Domaine Dupont’s method of filtration came with the creation of the famous “Chapeau Brun” (also known as “Keeving”). After crushing the apples and allowing the pomace to oxidize for a few hours, which is important for color and flavor, a hydraulic press will press as much liquid from the pomace as possible. The resulting liquid will be collected in a concrete or stainless steel container. Natural enzymes called pectins (polysaccharides) take over and attract nutrients that are floating in the liquid. They work in a very similar fashion to finings in beer.
Whereas finings pull yeast particles to the bottom of the cask, the pectins (now converted to pectic acid) “pull up” the nutrients and with it all rough parts that are floating in the apple juice(i.e. apple skins, stems, cores and seeds). It is driven by CO2 bubbles as the natural yeast has started to ferment the apple juice. As a result a firm brownish “hat” will form on the surface of the apple juice called “Chapeau brun”. The pectins will also combine with juice proteins and tannins, which will drop to the bottom of the juice as sediment. In between the bottom and the top “Chapeau brun” a very clear apple juice liquid will develop! This clear liquid will be drawn off, extremely carefully, into an adjacent fermentation tank. The fermentation will then proceed at a very slow pace as the “crazy” nutrients” have been left behind!
While the above methods of lautering/filtering have been invented due to the “lack of a husk” the world of beer, at least the world of “barley malt, has it much easier. Lautering of the mash through spent grain via false bottom is the method of choice. Simply usong the husk of the grain as medium to help separate the sweet malt liquid “wort” from spent grain through the false bottom at the bottom of the mash tun.
On the process of Keeving or “Chapeau brun”:
Anyone trying the art of keeving or “chapeau brun” should realize they are experimentalists and are pushing the boundaries. It is not a recipe based operation (do this, do that and do the next thing and you will get a perfect result)! There are lots of uncontrolled variables and until you have built up some experience you won’t know what works best for you.
Keeving’ is a way of making the ultimate style of naturally sweet sparkling cider. This is traditional both in Western England and the northwest of France, but whereas it has virtually died out as a commercial proposition in the UK, it is still very much alive for the production of ‘cidre bouché’ in France. The underlying principle is to remove nutrients from the juice by complexation with pectin at an early stage, to ensure a long slow fermentation which finishes and can be bottled while still sweet and without any fear of excessive re-fermentation later.
Please read our previous articles on Sandford Orchards & Domaine Dupont.