Processing fermented milk namely Mala from cow or goat milk

• Terminologies used in fermented milk processing (mala)  up to product evaluation

  • Pasteurization -

    This is temperature time combination meaning milk is heated to a given temperature set and held in the same temperature for the given time

  • Cooling -This is lowering the milk temperatures

  • -Inoculation -Adding  a viable culture

  • -Incubation - Giving the inoculated milk time for fermentation process  to complete

  • -Stir - Breaking of the curd  -This is done until there are no lumps observed

  • -Put or add color, flavor -  is just  the addition of color or flavor in the product

  • -Refrigerator  -Lowering the temperatures to a given temperature -Not must in mala though necessary

  • Evaluation - Making judgement of the value of the product

    
    

    SOME  CHARACTERISTICS OF MALA

Bacterial activity of fermentation in mala  does not continue even if Iin ambient temperatures

Acidity production stops when it reaches a certain PH,

Refrigerated mala`s aroma and flavor is more profound if its cooled.

Mala processing is a simple way of fermenting well pasteurized milk .The pasteurized milk is cultured with  the mala fermenting micro-organisms and incubated for the given period.

NB  - This course needs a person who can understand and willing to follow instructions on how to employ the technology. A basic knowledge of how to read and write is an added advantage.

Mala is a nutritious  milk product profitable to people of all ages. Its a complete food  rich in carbohydrates, proteins, fats, vitamins, minerals, fiber and water. It is important that everyone consumes these seven nutrients on a daily basis to help them build their bodies and maintain their health.

We have the responsibility of ensuring  safety of the public and  meeting the customers expectations; ensuring our product to be to the standards set by the governments.

Quality product is key for  growing /maintaining market space. Mala demand is high therefore  quality is key as we engage in the processing.

Things to note in processing

1. Processing can be done with or without machines. Its okay once the technology required is rightly captured and followed. Processing is easy and can be done in a home set-up.

2. Its required that the personnel handling milk should be medically certified.

3. The environment should be clean with fresh air and without any foul smells.

4. The animal being milked should be healthy/milk from a healthy animal .

5. The equipment should be of the recommended container for milk handling.

6. The detergents  used should be of light lather and mild smell so as not to introduce any form of contamination.

7. Milk should not have any traces of veterinary drugs or off flavor e.g. from feeds, and taints

8. Follow carefully the procedures for milk pasteurization, cooling , inoculation , incubation and finally evaluation of the final product

9. Milk  handling for the purpose of processing should be done hygienically to avoid contamination and that includes;- the time of production, transportation, storage and processing.

10. Adulteration by water addition in  milk is a prohibited culture (though this is done by unfaithful traders for a the purpose of gaining  much from their investment).

11. Once poor quality raw material  is processed the final product will also be poor.( Garbage IN garbage OUT.)

Note:

To maintain standard of the product; - Sample testing of the output against specifications is paramount in maintaining  the quality required .

How to segregate good quality milk from poor quality

Separation of milk depending on its quality is done by testing the milk before reception

These tests  are simple, quick  to perform and give quick results

a. Organoleptic test

b. Alcohol test

c. Phosphatase test

d. Lactometer test

e. Sediment test

f. Clot on boiling test

Organoleptic

In this test, a tester uses the five senses to do a judgement on the milk sample  to check if the milk is fit for the intended use.

Check for normal  smell, color, and consistency .

If it does not comply its either rejected, or segregated / separated for further tests.

Alcohol test

This test is for checking for acidity level.

Though milk has a natural acidity there is a limit required and the excess of it renders the milk not fit for any further processing i.e. heat treatment

Acidity increases due to;

Presence of mastitis bacteria,

Developed acidity

Colostrum  milk ( colostrum milk has high amounts of proteins which are unstable when  heated)

Procedure for alcohol test

Take small same amounts e.g. 2ml of milk and ethanol; Ratio 1:1 (Diluted alcohol of about 70 percent concentration) then mix

If the milk acidity is higher than expected; a precipitation or clots is noted .

If the acidity is normal no changes will be noted in the mixture.

Phosphatase test

Alkaline Phosphatase is an enzyme which is naturally present in milk, but is destroyed at the pasteurization temperature. Alkaline Phosphatase test is used to check if whether milk has been adequately pasteurized or whether it has been contaminated with raw milk after pasteurization.

Procedure

In the sample picked for testing deep the testing strip.

A color change is immediately realized if the milk is unpasteurized or re-contaminated with raw milk from blue to green.

No changes occurs  or is realized when the milk is adequately pasteurized and no recontamination

LACTOMETER TEST

How to check water by use of a Lactometer

Milk adulteration and the knowledge of the tests is necessary. The nutritional value of milk to human health needs no introduction at the same time; it is alarming that many vendors are adulterating it with water, detergents, caustic soda, starch, formalin, urea, ammonium sulphate, sodium carbonate which have harmful effect on the human health.

The greed for money has pushed them to the extent of producing synthetic milk which has no nutritional content. “Adulteration” is a legal term meaning that a milk product fails to meet federal or state standards.

Adulteration is an addition of another substance to milk in order to increase the quantity of the milk in raw form or prepared form, results in the loss of actual quality of milk. Milk adulterated is mainly done for financial gain but it can also be adulterated due to unhygienic conditions in processing, packaging, transportation, distribution etc.

Water is the most common adulterant used which decreases nutritional value of milk and lowers the quality too.

Lactometer checks for any added water in the milk. It works on the principle of specific gravity of milk. It consists of a Test-Tube and a Meter Bulb.

Using this instrument

Using this instrument is very simple;

Procedure

1. Put some milk in the test-tube.

2. Dip the meter bulb in it, the bulb going in first. You will notice that the meter bulb floats. The reading on the meter indicates how pure/impure your milk is.

3. The deeper the bulb sinks, the more dilute/impure the milk.

4. If the reading is at the red mark, it shows that the milk is rich and pure and visa versa.

Milk is one of the most important ingredients for children’s overall development, it is essential for adult health as well.

Milk is also widely used in food item like desserts, baking, tea and coffee etc.

The most common reason for milk adulteration is;

1. In order to meet the demand, the suppliers usually adulterate the milk and increase the quantity.

2. The adulterants like  glucose add to the thickness and viscosity of the milk while starch prevents curdling of milk.

3.   Due to lack of hygiene in milk handling and packaging, detergents (used during cleaning operations) are not washed properly and find their way into the milk. 

4. Other contaminants like starch, glucose, these adulterants are used to increase the thickness and viscosity of the milk --Formalin are used as adulterants as well  to preserve milk for a longer period.

5. Water turned out to be the most common adulterant in milk to increase the volumes . It reduces the nutritional value of milk. Water  contaminated (with pesticides, heavy metals),  poses a health risk to consumers

Sediment test

This is a test to check the amount of physical dirt in milk (sediments)

A clothing or sieve with fine openings  is used to pass the milk through .The amount of dirt that will remain on top will determine the level of dirt that was in the milk hence its acceptability.

Clot on boiling test

This test also tests for increased acidity in milk

Procedure

Heat the sample and if the acidity is low the milk sample will boil. If the acidity is high there will be noted a precipitation or clots.

When we say that milk is bad it means its quality is gone low as per the standard set in terms of colour ,flavour, smell, texture and density.

In this case we want to learn how to separate poor milk from bad milk using our natural God given senses before going further to use other ways of confirming the same if need be.

This means we are using sight, smell, touch/ feel, hear and taste

Note- taste is not recommended for raw milk

Another word for these tests is organoleptic whereby these takes a very short time to record the results. These tests are mainly used among the platform tests i.e. done before the milk reception and includes;

1.Sight

In this we use eyes to do the judgement whether the milk is good or bad. We check for its normal color, any physical dirt, particles, clots ,the container carrying or storing the milk, hygiene level of the environment  where the milk is stored, personnel handling the milk hygiene.

• The color of the milk should be creamy white and any deviation from this  will give room for this milk to be segregated for rejection or for further tests like laboratory tests whose results will take longer.

• Milk should not have any physical dirt like dust or particles like grass, hair or even insects like flies, ants as these poses a certain degree of compromise on quality either in production, transportation or storage  level.

• Accepting the same at the reception where grading is done may compromise the quality of the raw material we want for our final product.

• Further tests should be engaged if such milk should be received especially tests on the microbial load on the milk for an assurance that the milk can withstand the heat treatment to be subjected to during pasteurization.

• Once clots are evident on milk it means the milk is already sour therefore it cannot withstand  the heat treatment and  should be rejected.

• The type of containers recommended for quality milk is either stainless steell material ,aluminum material or glass. The other materials compromises the milk quality.

• The lid should be clean from inside when uncorked/opened from the container.

• The environment where the milk is being handled should be clean and free from unpleasant  smells. This is because milk is hygroscopic and  absorbs  the smell of its surrounding compromising the its quality.

• The personnel handling milk should be clean both body and clothing

• The personnel handling milk should be medically certified to avoid any transfer of communicable diseases and avoid compromising on milk quality

  
  

2.Smell

Milk which has been freshly milk should give cowish smell immediately the lid is opened. If the smell is sour it indicates the milk is sour and cannot withstand heat treatment.

Sometimes the milk can also have feeds smell which will  not be the best quality as a raw material ;meaning the same milk will affect the final product. Such milk should be rejected.

3.Touch or feel

In this case you can touch or feel the temperatures of the container to check if the milk inside the container is chilled ,warm or hot. From the informed information; depending on what you will require as from its temperatures ,you can make a decision either to receive or reject.

4.Hear

You can hear a hissing sound when there is a fermentation process going on.

In such a case the milk cannot be subjected to any further heat treatment therefore it`s to be rejected.

5.Taste

Tasting is not recommended for raw milk because milk can be from a sick animal which had a communicable disease

NB

Milk meant for production of ANY milk products(  IN OUR CASE MALA) must undergo heat treatment i.e. pasteurization

That is why any  test confirming the milk has higher acidity means it cannot withstand heat treatment and

such milk should not be received but rejected as a raw material.

Process adherence is when a person or team clearly understands an assigned process's goals, purpose and scope, how to follow the process and obtain expected results.

This also can mean executing a process using the defined standards even when you can do it through alternative approaches to achieve the same result.

Fermented milk (mala )is a very perishable product and needs a cold chain to maintain its quality.

This is a very nutritious product and a complete food.

Production of quality mala - needs;

1. Selection of good quality raw milk

2. Pasteurization of the raw milk

3. Cooling of the pasteurized milk to the inoculation temperatures conducive to the bacteria for fermentation (stature culture)

4. Inoculation - Putting or adding the culture

5. Incubation -This is the period set for the fermentation process to  complete

6. Stirring -This is the breaking of  the curd to a thick liquid mixture

7. Refrigeration -It is lowering the temperatures to  FRIDGE CONDITION

8. Procedure

   • Select the good quality milk

     Milk which has passed the platform tests and any other i.e. it had no adulteration, no foul smell, has low acidity level, has its right color ,no residues of veterinary drugs etc.

• Pasteurize the raw milk

  Milk is heated to destroy the pathogenic bacteria  and being careful  not to destroy the heat sensitive vitamins which require slow heat inducement

• .Heat the milk up to 90-95 degrees centigrade and hold it for 10-15 minutes.

• It is usually recommended if mala has to be added sugar it should be done during the milk pasteurization so that sugar is added to the milk at the rate of 4-5 percent of the milk volume to be used. This is optional as most customers prefer sugarless mala

• If there are any impurities in sugar the pasteurization will address the this and will avoid contamination of the product as compared  to when the sugar is added after the product is ready (during consumption)

Note:

In a situation where there is no Pasteurizer make sure milk  is not heated directly meaning; container containing milk to be  pasteurized should be heated through water media( meaning heat water then the heat from the water heats the milk container)

• Cooling

  Cooling is lowering the milk temperature to the temperatures required for inoculation  favorable for the lactic bacteria. For the case of Mala we cool the pasteurized milk up to 20 - 25 degrees centigrade  which is favorable for the fermenting bacteria for mala

• Inoculation

  This is putting or introduction  of the starture culture bacteria  into the pasteurized milk selected for mala production .After the introduction the milk is stirred for about 5 minutes for the even distribution of the bacteria in the the whole batch ready for the next stage of process.

• Incubation

    This is the period set for the fermentation process to  complete. It take 16 - 18 hours  at room temperatures .At the end of these said hours  there is a curd ( thick uniform body)formation.

• Stirring

  This is the breaking of  the curd to a thick liquid mixture.

• Refrigeration

  It is lowering the temperatures to  FRIDGE CONDITION. This is not a must for mala as the PRODUCTION OF ACIDITY IN THIS CULTURE IS MAXIMUMLY attained at a certain  level of PH where its process stops.

• Packaging

  Packaging is optional as this depends on the final destiny of the product