Agriculture Reference
In-Depth Information
the nature of physical and chemical changes during ripen-
ing, which are infl uenced by the cultures, chemicals, or
fl avor ingredients added to the curd during manufacturing
(Kosikowski, 1977 ).
In contrast to the production of many semihard and
hard types of cow milk cheeses, the manufacture of goat
cheese is referred to as a “ cottage industry. ” The vast
majority of goat cheeses in the U.S. are of the soft-body
type with one-third of them spice-added. Nutrient compo-
sitions of different varieties of goat cheeses produced in
the U.S. are shown in Table 14.8. Almost all French goat
cheeses are of the natural drainage type associated with
slow coagulation. France is known to produce many exotic
types of goat cheeses, including Crottin du Chavignol, Les
Pyramides, Sainte Maure, Chabis, and Chabicou
(Kosikowski, 1986). Other specifi c varieties of cheeses
made from goat milk or a legal mixture of goat and ewe
milk from other countries are Laruns, Peroil, Cabroles,
Lightvan, Bryndza, Bulgarian White, Akavi, Cachcaval,
Canestrano, Canniotta, Gjetost, and Feta (Kosikowski,
1977 ; Park and Guo, 2006 ).
The Agricultural Handbook No. 54 of the USDA
(Sanders, 1969) describes over 400 varieties of goat
cheeses and lists over 800 names of cheeses, made from
goat milk or combinations of goat with other species milk
such as cow, ewe, or buffalo. Most goat cheese varieties,
which are consumed fresh, are set by an acid (hydrochlo-
ric, lactic, vinegar, lemon, lime, whey) coagulation process,
whereas cheese varieties consumed after ripening are
generally made by the enzyme (rennet, chymosin, certain
herbs) setting process.
Various techniques have been employed to improve the
texture of yogurt for many centuries, including increasing
solids contents and enzymatic cross-linking using different
sources of proteins. The most common methods are to
increase the amount of total solids in the milk by supple-
mentation with milk powder, by condensation to reduce
water content, or by adding sheep milk with its high solids
content. The higher the level of solids in milk, the greater
and better the viscosity and consistency of the yogurt.
Powdered and Condensed Goat Milk Products
Signifi cant quantities of goat milk powder are commer-
cially produced especially in the U.S. and New Zealand.
Powdered products, including whole milk, skim milk,
whey, cream, ice cream mix, protein concentrates, and
infant foods, are produced by several methods of drying
the liquid such as spray drying, drum drying, and freeze
drying.
Evaporation processing of goat milk is usually per-
formed under reduced pressure, primarily to allow boiling
at a lower temperature and thus prevent fl avor damage due
to heating. Evaporated goat milk is processed with similar
evaporation facilities as performed for evaporated cow
milk products. General composition of evaporated goat or
cow milk has 7.5-9.0% fat, 17.5-22% milk solids-nonfat,
and 25-31% total solids, while those of powdered goat
milk contains average 28.2% fat, 65.9% solid-nonfat, and
94.1% total solids, respectively (Park and Guo, 2006).
Other Goat Milk Products
Goat milk butter is commercially manufactured in
several countries including the U.S. and Great Britain.
Buttermilk is usually made from skim milk using this by-
product after churning butter out of sour cream or directly
with bacteria inoculation from goat skim milk (Park and
Guo, 2006 ).
Acidophilus milk can be made from goat milk by adding
Lactobacillus acidophilus
, which can convert a high
amount of the lactose to lactic acid (2%). Pasteurized
milk is inoculated with
Lactobacillus acidophilus
, which
destroys other competing bacteria antagonistic to man in
the lower intestine (Kosikowski, 1977).
Kefi r is made from pasteurized, fat-standardized, or de-
creamed goat milk and is an acidic, slightly foamy product.
Kefi r is produced by a combined acidic and alcoholic fer-
mentation of symbiotic lactic acid bacteria and yeast “kefi r
grains. ” Kefi r usually contains 0.6-0.8% lactic acid, 0.5-
1.0% alcohol, and carbon dioxide.
Ghee is an Indian (and Middle East) clarifi ed butterfat
product, which is manufactured by fermenting whole goat
Goat Yogurt
Goat milk yogurt is produced and consumed in the
Mediterranean and many other countries. In the U.S., a few
domestic commercial goat yogurts and some imported
products have been available. Goat milk yogurt can be
made in a similar manner to cow milk yogurt. One of the
main problems in manufacturing goat milk yogurt is the
weak curd and lack of consistency in curd tension and
viscosity upon coagulation compared with cow milk
yogurt. This is due to the difference in casein composition
between the two milks (Park and Guo, 2006).
Yogurt is usually made with the symbiotic growth of
two bacteria:
Streptococcus thermophilus
and
Lactobacillus
delbrueckii
ssp.
bulgaricus
. These bacteria can not survive
gastric passage nor colonize the intestines, while
Lactobacillus acidophilus
and
Bifi dobacteria
do survive.
Therefore, yogurt with these bacteria are popular due to
their potential therapeutic benefi ts (Park and Guo, 2006).
