Milk can be safe for several days after the expiration date. The best before dates of food and drink products are linked to their quality rather than their safety. Drinking spoiled milk can make people sick, but it’s usually easy to tell when the milk is bad.
There are many types of best before dates on food and drink products, which can be confusing. Milk producers typically pasteurize it to kill bacteria before selling it. However, the milk can still spoil and become unfit for consumption.
In this article, we discuss how long milk can stay safe after the expiration date, and what the different dates mean on food and drink labels.
There is no universal length of time for how long it is safe to drink milk after the expiration date. Different types of milk can stay fresh for varying lengths of time.
Most of the milk that people buy in the United States has suffered
There are different methods pasteurization which can further extend the shelf life of milk. For example, ultra-pasteurized milk can last around 30 to 90 days. This longer shelf life is due to a higher heating temperature during processing.
Manufacturers make aseptic or ultra-high temperature (UHT) milk by heating the milk with sterile equipment and filling it under aseptic conditions into specially designed containers that can extend the shelf life to more than 6 months. The product itself can also be stable in storage, which means it does not require refrigeration until someone opens it.
It is advisable to avoid drinking believed, or unpasteurized, as it may contain harmful pathogens that can pose serious health risks.
In the United States, food and beverage packaging typically contains at least one date, which can have different meanings. These dates and their definitions may vary by label and are not subject to uniform government regulations. According to Food Safety and Inspection Service (FSIS), common dates on food and beverage labels include:
- Use by: This is the last date on which the manufacturer recommends that a consumer use the product for optimum quality.
- Best if used by: This date refers to the best flavor or quality of a product.
- Sell by: This date is a recommendation for how long a store should display the product.
- Freeze by: This is the best date to freeze a product to ensure the best quality.
These labels do not concern the quality of food or drink. With proper handling, all products should remain safe after any of these dates.
FSIS does not require product dating, but the voluntary use of dates must be truthful and comply with regulations, such as posting a day and a month. Infant formulas are an exception regulated by FSIS because they can be unsafe after the expiration date.
The FDA is now working with other federal agencies to standardize the use of “best if used by” to indicate the optimum quality date – except in the case of infant formula. The goal is to reduce the number of people throwing away products that have passed their expiration date and are still edible.
Milk naturally contains bacteria which can spoil itself and cause illnesses, such as Escherichia coli and Salmonella. Deterioration of milk is the result of an overgrowth of bacteria that compromises the texture, flavor and overall quality of the milk. Often, psychrotrophic bacteria, which can grow in cold conditions, are responsible for spoilage of milk.
There are several steps in milk production that aim to kill these bacteria to extend shelf life. Milk production follows the guidelines of the United States Department of Agriculture. Manufacturers will raise and milk dairy cows before storing milk at 40 ° F or below and transporting it for testing and processing. Milk processing involves:
- Pasteurization: Manufacturers heat milk to kill bacteria before cooling it again.
- Homogenization: An atomizer disperses the fat evenly in the milk and prevents it from floating upwards.
- Separation: A centrifuge spins the milk to separate the cream before recombining it with varying amounts of fat for different types of milk.
Several other steps may also be necessary, including additional filtration or ultra high temperature treatment.
Pasteurization kills most, but not all, bacteria in milk that can continue to grow after processing. After opening the milk at home, new bacteria can enter and grow, eventually causing the milk to spoil.
Best before dates are bad indicators of whether milk is safe to drink. The smell and appearance of milk are clearer signs of the safety of milk for consumption.
Spoiled milk will produce a sour smell because bacteria produce lactic acid. The smell will intensify once the milk becomes unfit for consumption. A yellowish color, scabs on the edges and lumps in the milk also indicate that it is extinct.
Processing milk has a significant effect on how long it stays fresh and safe for consumption. However, people can take steps at home to extend this period. Those understand:
- put the milk in the fridge as soon as possible
- put the lid back on the milk correctly after use
- keeping hot food away from milk in the refrigerator
- avoiding leaving milk out of the refrigerator for long periods of time
- keep the refrigerator temperature below 40 ° F
Drink small amounts of spoiled milk may cause no symptoms or a few minor symptoms, which usually go away on their own. For example, it can cause stomach pain, nausea, diarrhea, or vomiting. Bad milk is unlikely to cause long term problems.
- E. coli
The expiry dates are linked to the quality of the milk and not to the safety. Milk is generally safe to drink after the expiration date for at least a few days. People will generally be able to tell when the milk is bad because the smell and appearance indicate spoilage.
The type of processing the milk undergoes can affect the duration of its freshness. However, it is always advisable to store milk properly and safely, for example by keeping it in the refrigerator. Drinking spoiled milk can cause mild symptoms, but it’s usually not harmful in the long run.