What are reconstituted milk and recombined milk? Describe the preparation of Srikhand, Lassi and Yogurt.

Reconstituted Milk vs. Recombined Milk

While both involve processing, reconstituted and recombined milk differ significantly in their composition and production:

Reconstituted Milk

Reconstituted milk is produced by mixing dried milk solids (milk powder) with water. The ratio of milk powder to water is carefully controlled to mimic the composition of fresh milk, typically around 9% fat. This process is commonly used when fresh milk is scarce or unavailable, such as during the lean season.

• Process: Drying fresh milk to produce milk powder, then dissolving the powder in water.
• Composition: Essentially identical to fresh milk, as it's derived directly from fresh milk.
• Advantages: Consistent quality, extended shelf life of the powder.
• Disadvantages: Requires milk powder, which can be expensive.

Recombined Milk

Recombined milk is a blend of fresh milk and milk powder. It’s created to achieve a specific fat content or to standardize the milk's composition. The proportion of milk powder and fresh milk varies depending on the desired characteristics. It aims to provide a product with characteristics similar to fresh milk but with controlled composition.

• Process: Mixing fresh milk with milk powder in a defined ratio.
• Composition: Contains both fresh milk components and dried milk solids.
• Advantages: Flexibility in adjusting fat content and other components.
• Disadvantages: Can be more complex to produce than reconstituted milk.

Feature	Reconstituted Milk	Recombined Milk
Source of Solids	Milk Powder (100%)	Fresh Milk + Milk Powder
Composition	Identical to fresh milk	Blend of fresh and dried milk components
Complexity	Simpler	More complex

Preparation of Dairy Products

Srikhand

Srikhand is a traditional Indian fermented dessert made from strained yogurt. It originates from Maharashtra and Gujarat.

1. Fermentation: Milk is converted into yogurt through lactic acid fermentation by bacteria (primarily Streptococcus thermophilus and Lactobacillus bulgaricus).
2. Draining: The yogurt is then strained through muslin cloth for several hours to remove the whey, resulting in a thick, creamy mass.
3. Sweetening & Flavoring: Sugar and flavorings like cardamom, saffron, or fruit purees are added to the strained yogurt.
4. Chilling: The mixture is chilled for several hours to allow the flavors to meld.

Lassi

Lassi is a traditional Indian yogurt-based drink. It can be sweet or savory.

1. Yogurt Preparation: Similar to Srikhand, yogurt is prepared through lactic acid fermentation.
2. Blending: The yogurt is blended with water and sugar (for sweet lassi) or spices like cumin, coriander, and black salt (for savory lassi).
3. Chilling: The mixture is chilled before serving. Fruit purees can be added for flavored lassi.

Yogurt

Yogurt is a fermented milk product produced by bacterial fermentation of milk.

1. Milk Heating: Milk is heated to 85-90°C to denature whey proteins and improve texture.
2. Cooling: The milk is then cooled to around 43-45°C, the optimal temperature for bacterial growth.
3. Inoculation: A starter culture containing Streptococcus thermophilus and Lactobacillus bulgaricus is added.
4. Incubation: The inoculated milk is incubated at a constant temperature (typically 43-45°C) for several hours until the desired acidity and consistency are achieved.

The fermentation process converts lactose (milk sugar) into lactic acid, which lowers the pH and creates the characteristic tangy flavor and thickened texture of yogurt.