Processing and Preservation of Milk Products.

Raw Milk processing into Yoghurt product.

Welcome to my new topic  of Post harvesting technology.

Many peoples fall hardeness on how to manufacture Yoghurt and earn money from their cows raw milk yield. Some times they found themselves that, the harvested milk yield got lossed due to lack of knowledge on how to preserve, and process them into next level and get money cash to boost their living.

Today I'm going to share the principle tips on how to manufacture milk Yoghurt product. 

Materials and tools to prepare;

Raw Milk, Starter Culture ( It can be commercial or natural Starter culture), Heating Vessel, Thermometer for temperature measurement, Cooling Vat/Vessel, Filter funnels, Incubation Chamber/ Vessel, and also refrigerator.

1. Receipt of Milk from the farm production. Make sure raw milk has good quality as produced  from the farm source. It can be tested by using Lactometer test  if it was diluted with water, also milk should be tested before to check if if has undergone spoiled.

2. Filtration of milk

It should be filtered to remove any foreign matters that enterd within the milk during lactating, or transportation from the farm source.

3. Chilling 

The raw milk after milked from the cow, is supposed to be chilled at a refrigeration temperature of (4-6°C) to avoid any deterioration during Yoghurt manufacturing.

4. Heat treatment ( milk pasteurization) at 90°C of the thermometer  within 5 minutes for complete killing  micro organisms.

The high temperature short time heat treatment is applied usually by using  the heat exchanger machines that done in  the industry. But Locally method peoples can heat milk within 25-30 minutes depending to it's volume.

5. Cream Separation 

The cream formed at top layer of heated milk should be removed gently, and leave skim milk alone.

6. Cooling 

The skimmed milk is cooled at the cooling Vat until the thermometer  temperature falls to 42-43°C so as to bring the Yoghurt to the ideal growth temperature for the starter culture.

7. Inocculation of milk with starter culture. The 2-3% of yoghurt starter culture) commercial or natural cultures are mixed into cooled milk.

8.Incubation at 42-43°C for 4-6 hours.

The milk is held at that temperature untill a PH of 4.5 to allow fermentation to progress and form a soft gel and the characteristic flavor of yoghurt.

 

9. Cooling at refrigeration with 5-7°C.

The process is done so as to stop further Fermentation.

10. Addition of Flavor.

 Flavors from Strawbererry, Vannilla, banana can be added before filling and packaging to increase taste to consumers.

11. Filling and sealing at the packaging materials.

The packaged yoghurt.

12. Cold storage of the packaged yoghurt (5-8°C) for consumption.