Does evaporated milk expire?

In this brief study, we will address the query “Does evaporate milk expire?” We are also going to discuss the storage and shelf life of evaporated milk.

Does evaporated milk expire?

Evaporated milk is labeled with a best-before date instead of an expiration date, which means that its quality diminishes after the printed date, such as potential loss of nutrients, but it remains safe for consumption [1]. 

Of course, provided that it is unopened and properly stored. After opening, it is recommended to be consumed within 5 days maximum.

What Is the Shelf Life of Evaporated Milk?

Evaporated milk is commonly sold as a shelf-stable product, either in a can or a carton box, with a shelf life of 6 months to 1 year. 

Shelf-stable refers to products that while unopened can be stored at room temperature for a certain period of time. This is possible because the product undergoes sterilization to make the product commercially sterile.

For instance, canned evaporated milk undergoes sterilization, a preservation technique in which food is placed in airtight, vacuum-sealed containers and heat processed at 121 °C for a few minutes [2].

As the food cools, a vacuum seal is formed that prevents any new bacteria from getting in. Thus, as long as the canned good stays sealed in the package and is properly handled, sterility is maintained, and no microorganisms develop [2].

Evaporated milk sold in carton boxes also experiences sterilization as well as aseptic packaging, which helps protect it from light, oxygen, and the risk of recontamination.

However, once opened, evaporated milk should be refrigerated and consumed within 2 to 5 days.

Unopened, evaporated milk is maintained in a sterile environment, but as soon as it enters into contact with ambient conditions, microorganisms will find a very favorable situation to develop: nutrients, water, and adequate pH (6-7).

How to Tell Your Evaporated Milk has gone Bad?

You can tell your evaporated milk has gone bad if it shows a sour, acidic taste. This can be the result of bacteria multiplication, which consumes lactose, the sugar in milk, and produce lactic acid [3].

Acidity due to lactic acid can also cause your evaporated milk to form clumps, as a result of protein aggregation [3].

Other signs of spoilage are bitter flavor, caused by bacteria breaking down the protein in the product, and rancid flavor, attributed to milk fat degradation [3].

If you feel your evaporated milk is a bit alcoholic, it indicates that yeasts have grown in the product [3]. 

In all those cases, discard the product.  

How to Store Evaporated Milk?

Unopened, shelf-stable evaporated milk can be stored at room temperature, but in a cool, dry, and clean place, such as in the pantry or kitchen cabinet. Avoid proximity to a stove or any hot places. Temperatures below 30 °C are best [2]. 

According to the USDA [2], unusually high-temperature storage (above 50 °C) may result in harmless thermophilic bacteria multiplying and swelling or souring the product. If this happens, the evaporated milk should not be consumed.

Once you have opened the can or carton box, store leftovers in the refrigerator. Preferentially, move the evaporated milk from the original pack into an airtight container.  

Storing evaporated milk in cans or carton boxes may favor exposure to air, which can bring recontamination and promote oxidation reactions [2].

Is it possible to freeze evaporated milk?

Yes, it is possible to freeze evaporated milk but it is not recommended. When a product is frozen, after thawing, it changes its physical properties (color, flavor, texture), losing quality.

Is it possible to freeze unopened evaporated milk?

You can freeze unopened evaporated milk, but it is not recommended. If unopened, it does not make much sense to freeze evaporated milk. 

The main goal of freezing foods is to delay chemical reactions and microbial growth to prolong their shelf life. 

As shelf-stable evaporated milk is commercially sterile, freezing will not add any days to your product or contribute to extending the shelf life. 

Freezing evaporated milk could also compromise the seam integrity of the can which in turn would spoil the milk. 

Therefore, storing unopened evaporated milk properly at room temperature should be enough to keep its quality for a long period.

Is evaporated milk safe to eat after the expiration date has passed?

It is safe to eat evaporated milk (canned or boxed) after a few weeks of its expiring date, as long as the product has been well stored and upon opening the package, it does not present any sign of spoilage.

In the case of canned evaporated milk, the can must not present crushing, rust, dents, or swelling [2].

If all these criteria are met, the evaporated milk is supposed to be still sterile, and the product to be safe [2].

However, past its best-before date, the sensory features and nutritional values of the product are no longer guaranteed. 

In other words that means that passed the best-before date, the product is still safe, but it is possible that chemical reactions have taken place during the storage time, so upon opening, the milk is not at its finest. 

Conclusion

In this brief article, we answered the question “Does evaporated milk expire?” We also discussed the storage and shelf life of evaporated milk.

Citations

1.https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/food-product-dating.

 2.https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/shelf-stable-food

3. (2016). Spoilage of Milk and Milk Products. In Food Microbiology: Principles into Practice (eds O. Erkmen and T.F. Bozoglu)