Concentrated milk is made by removing a portion of the water from fresh milk, resulting in a thicker, more concentrated liquid. This process is done to extend shelf life, reduce storage space, and sometimes to add sweetness.
Here's a breakdown of the process:
Types of Concentrated Milk
There are two main types of concentrated milk:
- Evaporated Milk: This is milk that has had approximately 60% of its water removed. It's then heat-sterilized and canned.
- Sweetened Condensed Milk: This is also milk that has had about 60% of its water removed, but it has a significant amount of sugar added (typically around 40-45% by weight). The high sugar content acts as a preservative.
The Manufacturing Process
The general steps involved in making concentrated milk are as follows:
- Preheating: The fresh milk is preheated to destroy harmful bacteria and enzymes.
- Evaporation: The preheated milk is then subjected to a vacuum evaporation process. This allows the water to evaporate at a lower temperature, preserving the milk's flavor and nutritional value. Multiple-effect evaporators are often used for increased energy efficiency.
- Homogenization (Optional): For some types of concentrated milk (especially evaporated milk), homogenization may be performed to prevent fat separation during storage.
- Sweetening (For Sweetened Condensed Milk Only): For sweetened condensed milk, sugar is added during the evaporation process. The sugar concentration must be high enough to prevent spoilage.
- Cooling: The concentrated milk is then cooled.
- Standardization: Adjustments are made to meet legal and company specifications.
- Packaging: The milk is then packaged into cans or other suitable containers. Evaporated milk typically undergoes sterilization after canning to kill any remaining microorganisms.
Key Considerations
- Vacuum Evaporation: Crucial for preventing scorching and preserving flavor.
- Sugar Content (Sweetened Condensed Milk): A critical factor in preserving the product.
- Sterilization (Evaporated Milk): Ensures a long shelf life.
Concentrated milk offers a convenient and shelf-stable alternative to fresh milk, commonly used in cooking, baking, and as a coffee creamer.
