Bread is already a baked (cooked) milled grain i.e flour, and
seems like an great waste product to ferment. At least 50% starch
apparently.
I collected over a period 7kg of left-over bread. Dried it to make
sure it did not go mouldy, and just treated it like a milled and
cooked grain. You have the option of adding 10% malt to convert the
starch to sugars or using amylase enzymes. Yield is apparently about
60% sugar from the starch in the bread.
I used 1 kg bread/5 litres of water. (1 lb - 2 lb/gal seems the norm)
Method:
- Crush bread (gelatines easier)
- Raise temperature of water to 75C ( I used a 60 litre HDPE open-top
plastic drum with 2/1500W jug elements screwed in)
- Add crushed bread
- Wait for temperature to drop to 65C
- Add malt or amylase enzymes (I used enzymes)
- Hold at 65C for at least 1 hour.
- Cool to 24C (overnight)
- Add yeast (You could first strain off the sugar rich liquid for a
clean wash)
Left over bread can also be used as a supplement with a sugar wash to
provide nutrients for the yeast.
'Bouza' which has been known in
Egypt since the days of the Pharaohs. See http://www.fao.org/docrep/x2184e/x2184e07.htm
Here is a redacted version.
Bouza (Egyptian beer):
To get a 5% abv beer you would use
- 4 kg coarsely ground wheat
- 1 kg wheat grain
- 30 litres water
Knead 4 kg coarse flour with a quantiity of water into a dough.
Cut dough into thick loaves and bake lightly.
Moisten with water the 1 kg of wheat grain and allow to germinate (3-5 days).
Sun dry grains, crush and mix with the bread loaves which are soaked in water in a fermenter.
Add active slurry from previous mash. Ferment.
Bread is also still fermented to make a 'bread kvas' by the Eastern
Slavs (Ukrainians, Belarusians, Russians) and the word 'kvas' is
mentioned in 10th century Kievan chronicles. 'Kvas' is a generic word
covering weakly fermented drinks from malted grain, bread, fruits and
tree saps (maple & birch). Red beets were also fermented to make a
sour 'beet kvas' for borshch before the introduction of tomatoes
which provided sourness. 'Bread kvas' which is allowed to go sour, is
also used as a natural vinegar for borshch. Sometimes one comes
across the word 'kvas' and for comparison purposes here are several
redacted recipes.
Green malt and rye bread kvas:
- 1 kg green rye malt (barley & oats were also malted)
- 1 kg sliced dried dark rye bread
- 20 litres water
For a reddish color, roast a small quantity of the malted grain)
Crush malt lightly. Add green malt and bread to water (65C). Allow to
stand for several hours. Add sour dough starter (or 30 g yeast) and
allow to ferment for several days. Strain. Keep in cool place. Drink
when still effervescent or bottle as for beer.
Rye bread kvas:
- 1 kg sliced dried rye bread (lightly toasted in oven)
- 1 kg honey, molasses (or sugar)
- 20 litres water
Pour boiling water over bread, honey/molasses. Allow to cool (24C).
Add sour dough starter (or 30 g yeast) and allow to ferment for
several days. Strain. Keep in cool place. Drink when still
effervescent or bottle as for beer.
Crabapple and wild pear kvas:
- 7.5 kg apples (cores removed)
- 7.5 kg pears (cores removed)
- 20 litres water
Pour water over apples and pears. Cover and allow to ferment
(traditionally by wild yeasts). Strain. Keep in cool place. Drink
when still effervescent or bottle as for beer.
Kvas is a folk beverage, and there are many variations depending on
available material and personal taste. I have seen recipes using mint
or horseradish root for flavoring.