Yes, there are natural preservatives that can help extend the shelf life of tigernut milk without refrigeration or pasteurization. Here are some options:
High-temperature processing: While not pasteurization in the traditional sense, you can heat the tigernut milk to a high temperature (not boiling) and then immediately fill it into sterilized, airtight containers. This process can help to kill most of the bacteria and enzymes that cause spoilage.
Acidification: Lowering the pH of tigernut milk by adding an acid can help inhibit the growth of bacteria. For example, you can add lemon juice or citric acid to the milk, which not only acts as a preservative but also adds a tangy flavor to the milk.
Use of natural preservatives: Some natural substances have antimicrobial properties that can help preserve tigernut milk. For instance, adding a small amount of cinnamon, clove, or other spices with antimicrobial properties may help extend shelf life.
Salt: Adding a pinch of salt to tigernut milk can help inhibit bacterial growth and spoilage.
Sugar or sweeteners: Sugars act as preservatives by reducing the water activity in the milk, making it less conducive to bacterial growth. You can add a small amount of sweetener like sugar, maple syrup, or honey to the milk.
It's essential to remember that even with natural preservatives, the shelf life of tigernut milk will be shorter compared to pasteurized and refrigerated milk. Additionally, the quality and safety of the milk can still be affected by factors like hygiene during preparation and the storage conditions.
If you intend to store tigernut milk for an extended period or if you're concerned about food safety, refrigeration or pasteurization remains the most reliable and recommended method to ensure its preservation and safety. Always use your judgment and follow proper food safety guidelines when preparing and storing homemade beverages.