Biomedical Engineering Reference
In-Depth Information
able to utilise lactate as a sole carbon source, which demonstrates a good adaptation
to sour conditions [
27
] .
11.7
Chicha
Chicha is a fermented corn-based beverage consumed mainly in Southern Africa.
The manufacturing technique is quite unique, because human saliva is used as a
source of amylase enzyme, which converts the starch of corn into fermentable sug-
ars. The primary microorganisms are yeasts, especially
S. cerevisiae
, bacteria from
the species of
Lactobacillus
,
Leuconostoc
and
Acetobacter
, as well as moulds, such
as
Aspergillus
[
21
] .
11.8
Kishk
Kishk is a traditional fermented product, which is still consumed in Egypt, Syria
and in many Arabic countries. It is made of dough, which contains salt and fer-
mented skim milk. In addition, oat groats, oat flour, pre-cooked wheat groats (also
called
burghol
) or wheat flour can be used as an ingredient of kishk. Most usually,
the dough consists of a mixture of fermented milk and burghol. The dough is
kneaded once a day for 6 days at 35 °C to hydrate and gelatinise the starch.
The fermentation of kishk is spontaneous and takes place during this period
mainly by
L. plantarum
,
L. brevis
,
L. casei
,
Bacillus subtilis
and certain yeasts
[
21,
30
] .
After 6 days, the dough is moulded into small pellets, which are set into trays to
dry in the sunshine for a week. The dried pellets are ground either traditionally by
hand or in grain stores in industrial scale production. The beverage is produced by
dissolving the ground pellets into hot water. Fermented kishk products have ele-
vated levels of minerals and they are good sources of b-glucan and dietary fibre.
Fermentation and drying also affects the shelf life of the product positively [
30
] .
11.9
Kvass
Kvass is a fermented cereal beverage consumed in Eastern Europe. It is produced
from rye malt, rye flour, stale rye bread and sucrose. In addition, barley malt or
flour, as well as other cereals can be used as ingredients. A special type of kvass malt
(fermented rye malt) is often used for the typical aroma characteristics of kvass.
Kvass resembles Turkish boza with respect to the composition of the final product
as well as the microflora [
31,
32
] .
