cultered milk

CULTURED
MILK HOW IT PRESERVE?

CONTENTS:

02 DEFINITION, TYPES
OF CLASSIFICATION

03 THE PROCESS &
FOOD FLOW

05 MECHANISME
INVOLVED

09 GUIDELINE TO
PRESERVE CULTURED
MILK DRINK

10 ISSUES THAT ARE
RELATED TO
PRESERVATION OF
CULTURED MILK

11 EXAMPLES OF FOODS

12 ADVANTAGES &
DISADVANTAGES,
CONCUSION

WRITTEN BY:
MUHAMMAD IRFAN BIN MOHD ZAINUDDIN (THM1122DA)
HARITH HAIKAL BIN MAZLAN (THM1122DA)
NOR AINI BINTI GHAZALI (THM1122DA)
NOR AINNISHA BINTI SALEHUDIN (THM1122DA)
NURUL SYAHIRAH BINTI ADRI AZREEN
(THM1122DA)

PREPARED FOR:
SIR IZHAR HAFIFI BIN ZAINAL ABIDIN

definition types of
classification
ultured milk is the
01 Famous
C product resulting from Cultured Milk
Cultured buttermilk
the souring of Sour cream
skimmed or partially Yoghurt
skimmed milk by the
addition of a culture of 02 Lesser-known
lactic acid bacteria. Products
There are two broad
categories which are Kefir
by use of lactic acid Koumiss
bacteria which grow Acidophilus milk
well at ambient Yogurts containing
temperature (25-30°C), Bifidobacteria
known as Mesophilic
starter cultures and 03 Cultured Dairy
the other type is the Foods
one made by use of
lactic acid bacteria Excellent sources of
which grow well under calcium and protein
warm conditions (38 - Help to establish and
45(C), known as maintain beneficial
Thermophilic starter intestinal bacterial flora
cultures. Reduce lactose
intolerance

02

THE PROCESS AND
FOOD FLOW

03

04

MECHANISME INVOLVED

Functions of Starters in Food Fermentations.

Dairy starter cultures are particularly well characterized and
can be used to illustrate some of the functional properties of
starters in food fermentations.

Functions Result/Mechanisme
Acid production
Gel formation
Flvour compound Whey expulsion (syneresis)
production Preservation
Preservation Flavour development

Gas formation Formation of diacetyl and
acetaldehyde

Lowering of pH and redox
potential
Production of bacteriocins such
as nisin
Production of hydrogen
peroxide
Formation of d-leucine
Production of lactate/lactic acid
Acetate formation

Eyehole formation
Production of openness to
facilitate ‘blue veining’

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Stabilizer Body and viscosity
formation improvement
Increase cheese yield?
Lactose Reduced use of milk powder
utilization in yogurt making

Lowering of Reduce potential for gas and
redox potential off-flavor development
Make products more
acceptable to the lactose
intolerant

Preservation
Aids flavour development

06

Preservation and Sterile liquid milk freshly inoculated
production of starter with an active starter culture is deep
cultures: frozen at −30 to −40 °C to preserve
the mother or feeder culture. Such
Frozen starters frozen cultures can retain their
Yoghurt starter activity for several months when
cultures can be also stored at −40 °C and this method of
be preserved in the culture preservation became popular
frozen form and such in the dairy industry because deep-
cultures are produced frozen cultures produced in
by two different centralised laboratories could be
routes: dispatched to a dairy in dry ice
Deep or sub-zero whenever required. These cultures
freezing (–30 to −80 are mainly packed in plastic
°C). containers and a typical example is
Ultra-low temperature the Astell-type plastic bottle. The
freezing (–196°C) in reactivation procedure for these
liquid nitrogen. deep-frozen cultures is as follows:

Remove starter from freezer, that
is at −40 °C.
Thaw the starter very quickly in
water bath at 20 °C.
Incubate at 42 °C until the desired
acidity is reached.
Cool and store overnight in the
refrigerator.
Subculture for the propagation of
feeder for bulk starter

07

Milk protein gels

Production of Exopolysaccharides:
Some yogurt starter cultures produce exopolysaccharides (EPS)
during the fermentation process. They can be viewed as a naturally
produced thickener. This EPS can be produced as a capsular layer
around the bacterial cell or excreted into the medium to produce an
effect sometimes called ‘ropy’ or ‘stringy’. Popular examples of ropy
yogurt are Villi and Langfil from Scandinavia.
Capsular EPS has little impact on yogurt gelation or texture. Ropy EPS
can be either charged or uncharged. It is possible that charged EPS
may associate electrostatically with the caseins, depending on the pH
of the milk, whereas uncharged EPS may influence gelation via a
depletion flocculation-type mechanism (Girard & Schaffer-Lequart,
2007).

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GUIDELINE TO Cultured milk will last longer and be safe to
PRESERVE drink if we keep it in the chiller. It is advisable
CULTURED to store cultured milk in a chiller between 5-
MILK DRINK 10°C. Even though it will not spoil within a few
hours at room temperature, always remember
to keep them in the chiller as soon as we can.
For products like cultured buttermilk, put it in
the chiller immediately in the original
container and keep the container closed. The
product will last within 2 weeks.

09

ISSUES THAT ARE
RELATED TO
PRESERVATION OF
CULTURED MILK

WHAT CAUSES CULTURED IS CULTURED MILK BAD FOR
DAIRY PRODUCTS TO YOU?
COAGULATE?
Several studies have found that consuming
This is due to the action of natural lactic acid milk products cultured with probiotic bacteria
bacteria on milk sugar, which converts it to on a regular basis can help keep the skin
lactic acid, causing the milk protein to hydrated, robust, and healthy-looking.
coagulate. Selected lactic starter cultures are Crosstalk between the gastrointestinal and
employed to ferment milk during the immune systems is thought to be involved in
manufacturing of a variety of cultured dairy the effects of cultured milk products on skin
products in the modern dairy processing health.
industry.

WHY IS THE CULTURED MILK WHAT ARE SOME NEGATIVE
REFRIGERATED AT THE END OF ASPECTS TO THE
THE PROCESS? FERMENTATION PRODUCTS IN
HUMAN HEALTH?
Acidophilus milk is typically low fat or nonfat
milk with active Lactobacillus acidophilus Some people, however, may experience severe
cultures added. The milk can be refrigerated to side effects after consuming fermented foods.
prevent the harmless bacteria that produce
sweet acidophilus milk from growing further. Bloating. The most common reaction to
It can also be incubated at 38°C until it forms a fermented foods is an increase in gas and
curd. bloating for a short period of time.
Migraines and headaches.
Intolerance to histamine.
Food-borne illness.
Infection caused by probiotics.
Resistance to antibiotics.

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EXAMPLES
OF FOODS

11

ADVANTAGES &
DISADVANTAGES

ADVANTAGES DISADVANTAGES

01 It helps restore proper 01 It is linked with the
bacteria balance in development of gastric
the intestines. cancer.

02 It improves heart 02 Store-bought items
health. lose beneficial
bacteria.
03 It improves the immune
system.

In conclusion, there are a lot of benefits that
we can gain from drinking cultured milk
such as the bacteria in the milk helps boost
the immune system. It is good to drink after
meals when the acidity in the stomach is
lower as the bacteria will reach the
intestines alive.

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