what is shelf life

What is Shelf Life? And Expiry Date?

What is shelf life?

Shelf life is defined as the amount of time a commodity can be stored before it becomes unfit for use, human consumption, or sale is known as its shelf life. In other words, it might apply to whether a product should be removed from a pantry shelf or simply removed from a store shelf.

The average lifespan of humans is about 73 years globally. However, some people live up to about 100 years while other die before their 73rd birthday.

The period between when a person is born and when they die is their lifespan.

For shelf life, you can consider it the ‘lifespan’ of manufactured products. It is the time when a product is made and packaged to when it becomes unfit for use.

Some products have shorter shelf lives. For instance, fresh milk has a shorter shelf life of a few hours while long life milk can last for up 90 days.

Other times have much long shelf lives last a couple of years before going bad.

expiry date

Expiry date refers to when a product goes bad and is no longer safe to use or consume. Expiration usually requires an item to be thrown away.

Best before date is the indicative period when a product or food is no longer in its original perfect condition after manufacture but it can still be used. After ‘best before’ date has passed, a product may lose taste, some nutrients, or freshness but it can still be used.

Shelf life applies to the following items:

  • Cosmetics
  • Food
  • Beverages
  • Medical devices
  • Medicines
  • Explosives
  • Pharmaceutical drugs
  • Chemicals
  • Batteries
  • Chemicals
  • Detergents
  • Other perishable items

In some countries, packaged perishable items must have a ‘best before’ date or freshness date. In some jurisdictions, the concept of an expiration date is comparable but legally separate.

What Does The Term Shelf Life Mean?

Although your product may undergo some changes from the time it is manufactured to the time it loses its usability, this end of a product’s shelf life is defined as the time at which the product is no longer acceptable to consumers.

Sensory features, a loss of chemical stability, changes in the physical quality, microbial development, vitamin breakdown, and other undesirable alterations are all possible consequences of something reaching the last stage of shelf life.

What Causes the End of Shelf Life?

The very first step in the determination of shelf life is to figure out what causes your product’s shelf life to expire in the first place. The shelf life of a product is influenced by three major factors:

  • Microbial properties – Mold or possibly disease-causing microorganisms that develop to dangerous quantities in your product.
    • Some products are prone to microbial activities, which cause chemical reactions. For example, milk begins to ferment and then goes bad as bacterial growth exceeds a certain limit.
  • Chemical changes – Chemical transformations in products include browning, lipid oxidation, enzymatic reactions, and other processes.
  • Physical changes – Physical deterioration includes changes in texture, caking and clumping, moisture migration, and other phenomena, among other things.
    • These three elements can be inherent within the product itself, depending on how it is produced.
    • Alternatively, they can be extrinsic, meaning that they are related to storage circumstances, including storage humidity and temperature, as well as the type of packing.

All these factors influencing shelf life are interconnected with, and can be regulated by, water activity in one way or another.

To learn more about how water activity is utilized to forecast, prevent, and control the conditions that cause shelf life to expire, please check regulations in the link here.

Factors that determine shelf life of food

  • Raw materials
  • Water activity
  • Composition and formulation of the product (additives used)
  • Available oxygen
  • Total acidity and pH value
  • Potential Redox

Methods for determining shelf life of food

  1. Direct method – These refer to real-time studies in which the product is stored under conditions comparable to those it will face in the field and its evolution is tracked at regular intervals. 
  2. Challenge test – This method entails introducing microbes into food experimentally during the manufacturing process, exposing the product to the conditions it will face in the real world. 
  3. Predictive microbiology – This approach is based on mathematical and statistical models and investigates the various microbial reactions of foods to diverse environmental conditions in order to anticipate the behavior of the microorganisms in the product. This form of analysis is widely practiced when designing a new product.
  4. Accelerated shelf life tests – With these tests, temperature, oxygen pressure, and moisture content are all altered in these experiments to speed up the spoiling responses of a product. These testing methods allow one to forecast how foods will behave under various settings and anticipate how they will change over time.
  5. Survival method – It is a sort of investigation that is based on a consumer’s perception of a product’s physical qualities. It entails determining people’s attitudes toward the same product manufactured at different times in order to decide whether or not they would go ahead and eat it.