Yoghurt or Yogurt
From Wikipedia, the free encyclopedia
Yoghurt or
yogurt, or less commonly
yoghourt,
joghurt
(in German) or
yogourt, is a dairy
product produced by bacterial fermentation of milk. Any sort of milk may
be used to make yoghurt, but modern production is dominated by cow's milk.
It is the fermentation of milk sugar (lactose) into lactic acid that gives
yoghurt its gel-like texture and characteristic tang. It is often sold
in a fruit, vanilla, or chocolate
flavour, but
can also be
unflavoured.
History
There is evidence of cultured milk products being produced as food for
at least 4,500 years, since the 3rd millennium BC. The
Bulgars
(also
Hunno-Bulgars), a Turkic-speaking
people from
Aryian-Pamirian origin, migrated
into Europe starting from the 2nd century AD, eventually settling on the
Balkans by the end of the 7th century AD. The earliest yoghurts were probably
spontaneously fermented, perhaps by wild bacteria residing inside goat
skin bags used for transportation.
Yoghurt remained primarily a food of India, Central Asia, Western Asia,
South Eastern Europe and Central Europe until the 1900s, when a Russian
biologist named IlyaIlyichMechnikov
theorized that heavy consumption of yoghurt was responsible for the unusually
long lifespans of Bulgarian peasants. Believing
Lactobacillus
to be essential for good health, Mechnikov
worked to popularize yoghurt as a foodstuff throughout Europe.
It fell to a Spanish entrepreneur named IsaacCarasso
to industrialise the production of yoghurt.
In 1919 he started a commercial yoghurt plant in Barcelona, naming the
business Danone after his son — better known
in the United States
as 'Dannon'.
Yoghurt with added fruit marmalade was invented (and patented) in 1933
in dairy RadlickáMlékárna
in Prague. The original intention of this combination was to protect yoghurt
better against decay.
Yoghurt was first commercially produced and sold in the United
States in 1929 by Armenian immigrants,
Rose and SarkisColombosian,
whose family business later became Colombo Yogurt.
Etymology of 'yoghurt'
The word derives from the Turkish
yo?urt
(pronounced
[j??urt])
deriving from the adjective '
yo?un', which means
"dense" and "thick", or from the verb
yo?urmak,
which means "to knead" (possibly "
yo?urmak" the
verb originally meant "to make dense"), a reference to how yoghurt is made.
The letter ? is silent between back vowels in Modern Turkish, but was formerly
pronounced as a voiced velar fricative
[?]. English
pronunciation varies in different regions according to the local accent
but common pronunciations include
/?j?g?t/
and
/?jo?g?t/.
Contents
Yoghurt making involves the introduction of specific "friendly" bacteria
into milk under controlled (very carefully in industrial settings) temperature
and environmental conditions. The bacteria ingest the natural milk sugars
and release lactic acid as a waste product; the increased acidity, in turn,
causes the milk proteins to tangle into a solid mass, (curd, denature).
The increased acidity (pH=4–5) also prevents the proliferation of other
potentially pathogenic bacteria. To be named yoghurt, the product should
at least contain the bacteria
Streptococcus salivariussspthermophilus
and
Lactobacillus bulgaricus (official
name
Lactobacillus delbrueckiissp.
bulgaricus).
Often these are co-cultured with other lactic acid bacteria for either
taste or health effects (
probiotics). These include
L.
acidophilus,
Lactobacillus casei
andBifidobacterium
species.
In most countries a product may only be called yoghurt if there are
live bacteria present in the final product. Pasteurized products (which
have no living bacteria) are named fermented milk (drink).
In the US non-pasteurized yoghurt is sold as containing "live active
culture" (or just as "live" ), which some believe to be nutritionally superior.
In Spain, the yoghurt producers were divided among those who wanted to
reserve the name yogurt for live yoghurt and those who wanted to
include pasteurised yoghurt under that label
(mostly the PascualHermanos
group). Pasteurized yoghurt has a shelf life of months and does
not require refrigeration. Both sides submitted scientific studies claiming
differences or lack thereof between both varieties. Eventually the Spanish
government allowed the label yogurpasteurizado
instead of the former postrelácteo
("dairy dessert").
Because live yoghurt culture contains enzymes that break down lactose,
some individuals who are otherwise lactose intolerant find that they can
enjoy yoghurt without ill effects. Nutritionally, yoghurt is rich in protein
as well as several B vitamins and essential minerals, and it is as low
or high in fat as the milk it is made from.
Non-sweetened drinkable yoghurt is typically sold in the West under
the name "(cultured) buttermilk." This term is a misnomer, as the drink
has little in common with "true" buttermilk and is, in fact, most similar
to kefir.
Presentation
Yoghurt is often sold sweetened and
flavoured,
or with added fruit on the bottom (sometimes referred to as fruit bottom),
to offset its natural sourness. If the fruit is already stirred into the
yoghurt, it is sometimes referred to as Swiss-style. Most yoghurt in the
United
States has pectin or gelatin added. Some
specialty yoghurts have a layer of fermented fat at the top similar to
cream cheese (e.g. brands like Brown Cow Yoghurt). Fruit jam is used instead
of raw fruit pieces in the case of fruit yoghurts so that they can be stored
for weeks.
Yoghurt types
Dahi yoghurt
Dahi yoghurt of the Indian subcontinent is known
for its characteristic taste and consistency. The English term for yoghurt
in
India
is curd.
Labneh or Labaneh
Labneh yoghurt of Lebanon is a thickened yogurt
that is used to make sandwiches by itself, or with olive oil, cucumber
slices, olives, and various green herbs. It is also thickened further and
rolled into balls that are preserved in olive oil, and fermented further
for a few weeks before it is eaten. It is sometimes used with onions, meat,
and nuts as a stuffing for a variety of Lebanese pies or
Kebbeh???
balls.
Bulgarian yoghurt
Bulgarian yoghurt is popular for its specific taste, aroma, and quality
and is commonly consumed plain. The qualities are specific to the particular
culture strains used in
Bulgaria,
Lactobacillus bulgaricus
and
Streptococcus thermophilus bacteria.
This type of yogurt is often
labelled and
sold as Greek yoghurt, especially in British and American markets. Bulgarian
yoghurt producers are taking steps to legally protect the trademark of
Bulgarian yoghurt on the European market and distinguish it from other
product types that do not contain live bacteria.
Bulgarian yoghurt is often strained by hanging in a cloth for a few
hours to reduce water content. The resulting yoghurt is creamier, richer
and milder in taste because of increased fat content. Hanging overnight
is sometimes employed to make a concentrated
yoghurt similar to cream cheese. Yoghurt is also used for preparation of
Bulgarian milk salad. (Commercial versions of strained yoghurt are also
made.)
A cold soup (called tarator in Bulgaria
and cac?k in Turkey) made of yoghurt is
popular in Turkey
and Bulgaria
in the summertime. It is made from Ayran,
cucumbers, garlic and ground walnuts.
Yoghurt Drinks
Lassi is a yoghurt-based beverage, originally
from India where two basic varieties are known: salty and sweet. Salty
lassi
is usually
flavoured with ground-roasted
cumin and
chile peppers; the sweet variety
with rosewater and/or lemon, mango, or other fruit juice. Another yoghurt-based
beverage, a salty drink called
Ayran is
quite popular in Turkey, Bulgaria and Greece. It is made by mixing yoghurt
with water and adding salt. The same drink is known as
tan in Armenia.
A similar drink,
Doogh, is popular in the
Middle East between Lebanon and Iran; it differs from
ayran
by the addition of herbs (usually mint) and being carbonated (usually with
seltzer water). In the
United States,
yoghurt-based beverages are often marketed under names like "Yogurt Smoothie"
or "Drinkable Yogurt".
Kefir
Kefir is a fermented milk drink originating in the Caucasus. A related
Central Asian-Mongolian drink made from mare's milk is called kumis or,
in Mongolia,
airag. Some American dairies have
offered a drink called "kefir" for many years (though lacking the carbonation
and alcohol, and coming in fruit
flavours),
but began appearing (as of 2002) with names like "drinkable yoghurt" and
"yoghurt smoothie".
Home-made yoghurt
Home-made yoghurt is consumed by many people throughout the world, and
is the norm in countries where yoghurt has an important place in traditional
cuisine, such as Bulgaria, Turkey, Greece[1] and India. Yoghurt can be
made at home using a small amount of store-bought plain live active culture
yoghurt as the starter culture. One very simple recipe starts with a
litre
of low-fat milk, but requires some means to incubate the fermenting yoghurt
at a constant 43°C (109°F) for several hours. Yoghurt-making machines
are available for this purpose. A run of the mill heating pad found in
a pharmacy for muscle aches (set at medium), with a pot of tepid water
on top to place the milk in, works fine.
As with
all fermentation processes, cleanliness is very important.
-
Bring the milk to 85°C (185°F) over a stove and keep it there for
two minutes, to kill any undesirable microbes.
-
Pour the re-pasteurised milk into a tall,
sterile container and allow to cool to 43°C (110°F)
-
Mix in 120 ml of the warmed yoghurt and cover tightly.
-
After about six hours of incubation at precisely 43°C (110°F);
the entire mixture will have become a very
plain but edible yoghurt with a loose consistency.
-
The further below 43°C (110°F) the temperature, the longer it will
take for the yoghurt to solidify. If a precise means of temperature control
is not available, put the culture in a warm place such as on top of a water
heater or in a gas oven with just the pilot flame burning, or wrap a small
towel around the container. An electric oven with the light on may work
nicely, depending on the bulb size. You can tell it is done when it no
longer moves if you tilt the jar.
In
Japan,
Caspian
Sea Yoghurt is
a very popular home-made
yoghurt. It is believed to have been introduced into the country by researchers
in the form of a sample brought back from
Georgia
in the Caucasus region in 1986. [2] This Georgian yogurt, called
Matsoni
which is mostly made up of
Lactococcuslactissubsp.
cremoris
and
Acetobacterorientalis[3]
has a unique viscous, honey-like texture and is milder in taste than many
other yoghurts.
Caspian Sea yoghurt is particularly well suited
for making at home because it does not require any special equipment and
cultures at room temperature (20–30°C) in about 10 to 15 hours, depending
on the temperature. [4] InJapan
it is possible to buy a freeze-dried starter culture at big department
stores or online, but many people obtain a quantity of the yoghurt from
a friend and start making their own yoghurt from that.
-
General instructions: sterilise all utensils,
containers and lids in boiling water prior to use.
-
From freeze-dried starter: in a container stir starter into about 250 ml
of milk and cover with a lid. Incubation time is approximately 12-36 hours
from starter. Make the next batch as below (from the actual yoghurt as
the starter).
-
From yoghurt: In winter, use about one part yoghurt to four parts milk.
In summer use about one part yoghurt to nine parts milk.
-
Place the lid gently on top of the container so as to allow some air in,
but prevent contamination. Leave in a clean dry place for 10-15 hours or
until thick. In summer, this may be less than 10 hours and in winter, longer
than 15 hours.
-
Some thickening of the yoghurt will also occur in the refrigerator.
-
The yoghurt can be stored in the refrigerator for about 1 week or longer.
-
To reduce contamination, always make the next batch of yoghurt before using
the current batch, and use containers solely for making yoghurt and nothing
else.
Another Recipe
INGREDIENTS:
SERVES 6-8
1/2 gal. homogenized milk
1/2 cup yogurt (starter)** You can use up to one cup.
(make sure plain yogurt container states "live
culture")
1/2 pint heavy cream (Optional for more richness)
METHOD:
Pour the milk into a saucepan and bring to a boil, stirring constantly.
When it comes to a boil, add 1/2
pint of heavy cream, and pour into an earthen bowl or Pyrex dish.
When it is lukewarm (105 -110
degrees), stir the mahdzoon starter with a
spoon until it is smooth and dilute it with some of the warm
milk. Pour this mixture into warm milk and stir.
Wrap the warm milk (with yogurt starter), and leave it in a warm place,
undisturbed, for at least 8 to
10 hours. Yogurt should be set by then. Place pot in refrigerator until
cold, and ready to serve.
