Keeving Cider to retain natural sweetness
Keeving is The Production of a naturally sweet cider by controlling the fermentation
The Process of Keeving
When left to their own devices most ciders tended to ferment out to almost complete dryness. One method to develop a sweetness that is obviously not the result of adding saccharin or any other artificial sweetener is through the adaptation of a technique known as 'keeving', a method which is very popular among French cider-makers, especially in Normandy
- The minced pulp should be held for 24 hours before pressing to allow enzymatic changes to take place which should then cause the juice to separate out into layers within the fermentation vessel; a floating layer of pectate gel at the top, clear juice in the middle, and sediment at the bottom
- The traditional way of triggering a keeve is to add a mixture of chalk (CaCO3) and salt (NaCl) prior to Fermentation. However, commercial producers now tend to add calcium chloride (CaCl2). As the juice stands, natural pectin methyl esterase (PME) slowly converts the soluble juice pectin to pectic acid. This combines with the added calcium to form a calcium pectate gel which is insoluble. This is is buoyed up by gas from the incipient fermentation and so floats to the top forming the 'chapeau brun'.
- Although the PME is naturally present in the apple in small amounts, it can now be added from commercial sources to make the keeving much more reliable.
- As the pectate gel traps much of the nitrogenous vitamins and amino acids present in the juice, the middle layer of clear juice, which should be siphoned off, has now become low in the nutrients the yeast favours and thus inhibits its ability to work
- Slow fermentation of the natural yeast at low temperatures during the winter, allied with racking at a gravity of about 1025 degrees to arrest fermentation, produces a Cider with a high proportion of residual sweetness although a lower Alcohol Content
The details above were extracted from a report by Roy Bailey
Keeving in Pictures
Are there any good English suppliers of calcium chloride and pectalitic enzyme. I have been to France two years following to buy the "klercidre" kit from Standa Industries which works very well, and last year I used "Claraval" but I dont think I will be going this year. The quantity recommended with these kits was 330g of cal/chlor and 21ml of enzyme for 600lt Any info would be appreciated. Nick Poole