Food expiry dates or use-by dates are a key indicator to inform your customer of the safety and suitability to consume a particular food product. Setting the food expiry date of your products is a basic food safety requirement. The food expiry date is also known as shelf-life within the food industry. In this post, the basics of how to set and verify the food expiry date of your food products are covered.
Setting your food expiry date
Food expiry dates are generally set during your product development phase. It is very important to have an understanding of the microbiological, chemical, and quality hazards of the raw materials used, the production process, and also the finished product. A risk assessment is commonly used in this process. Potential hazards can be researched as a starting point.
When you have a good understanding of your potential hazards you can then have your finished food product tested for those hazards. This is usually completed in association with a food laboratory. Your product can be tested and assessed at various points in the shelf-life process. For example, if you believe the product will be safe to consume for up to 6 months, you would test at say Day 1, Day 30, Day 60, and so on. Your food laboratory is a good resource in helping with your initial testing frequency.
Packaging and process environment
When establishing the food expiry date, consideration needs to be given to your process environment as this may affect your ability to achieve your nominated shelf-life. Examples of processing methods that deliver an extended shelf life include flash pasteurisation and high-pressure processing.
The packaging that the product gets sold to the consumer needs to also be considered. Packing your food product in vacuum packaging or modified atmosphere packaging will generally allow you to achieve a longer shelf-life.
Using the food expiry dates of your competitors
Please do not use the food expiry dates set by your competitors. The raw materials, technology, and processes used by your competitors can and will most likely be very different from yours. This is especially the case in a smaller boutique food business compared to a major food manufacturing company.
What should I ask the lab to test for?
When deciding what ‘testing’ a laboratory should perform to determine the shelf-life of your product there is lots to consider. You need to have a clear understanding of:
- what the actual product is
- the raw materials used to make it
- what preservation methods you are using
- storage methods
- how you have manufactured the product
- the pathogens associated with your finished product and raw materials
When you know this information, the lab will have a better understanding of what you should be testing for. Common tests include:
- Standard Plate Count (SPC)
- Total Viable Aerobic Count
- Yeasts and Moulds
- Coliforms
- E.Coli.
- Listeria SP or Listeria monocytogenes
- Salmonella
- Clostridium Perfringens
- Bacillus cereus
- Rope Forming Bacillus
- Coagulase Positive Staphylococci
How do I find a food laboratory?
The easiest way is to just google “food laboratory near me”. You can also check out my article on How to Choose a Food testing Laboratory.
How much does it cost to get my food product tested?
This will be dependent on the food product being tested and also the type of test being performed. I am sure that your local food laboratory would be happy to give you a quote. You may also be able to download a price list from their website.
What pathogens are associated with my finished product or raw materials?
To find out what food pathogens are associated with the raw materials/ingredients go in to make up your finished product, have a look at the raw material specification sheets that are provided by the manufacturer of those raw materials (i.e. your suppliers).
For example, salmonella can be associated with chicken, so if your finished product contains chicken, you would have the lab test for salmonella. You can also check out the ‘FDA Bad Bug Book’. It is a great resource in seeing what food pathogens are associated with what foods.
Case Study
Thanks to Reyshell Maruqin for sharing how they calculated the expiry date of their product.
“At first, I let my product seat for a month and have it tested in the laboratory. When it passed the examination. I’ve set 1 month form the manufacturing date as its BEST UNTIL period. So, I was then able to sell my products in the market. And then, I let it seat for 2, 3, 4 months and so on, and have it again tested in the laboratory, then gradually I changed the date where it is safe for consumption (BEST UNTIL)”.
What is accelerated shelf-life testing?
You might be thinking, “I don’t have months and months to go through this process”. This is where accelerated shelf-life testing comes into play. Accelerated shelf-life testing is a process in which the product is stored at higher temperatures and/or humidity levels for a specified period of time, then tested for safety and quality.
You can talk to your local food laboratory to find out if they offer this type of testing service.
How can I extend the shelf life of my product?
The most common method used to extend the shelf life of a product is to add a preservative. Preservative food additives reduce the risk of foodborne infections, decrease microbial spoilage, and preserve fresh attributes and nutritional quality.
If you don’t want to add a chemical preservative, you can try, if your product allows, physical techniques like dehydration, UV-C radiation, or freeze-drying.
If you are going to use a chemical preservative, please make sure you comply with the usage laws in your country of manufacture and country of sale. E.g. FDA
Developing a shelf-life verification program
Once you have established the initial shelf life, you still need to routinely check that the food product is maintaining that food expiry date or determined shelf-life. If you are required to comply with any of the major GFSI recognised standards, this will be a mandatory requirement. This is considered to be a verification activity where the question of “Is this food product still safe at the set food expiry date?” needs to be answered. When setting up your food expiry date verification program make sure that it includes:
- Testing of retention samples at different points in the product shelf life eg. day 2, day 45, day 100 for all parameters.
- Testing the product beyond the stated shelf life eg. test at 13 months if the product has a 12-month shelf life indicated on the label.
- Challenge testing of the product to support your storage instructions eg. to account for the cold chain process post-dispatch.
- Challenge test as if packaging may be compromised. For example, if air remains in a cryovac product or the gas mix was incorrect when using MAP packaging.
How often should you complete shelf-life verification?
There are key times when the food expiry date or shelf life of your product needs to be verified. This includes:
- Whenever you change the recipe or formulation of your food product. This can include changing the ongoing weights.
- Whenever you introduce a new raw material or change a raw material used in your food product. This includes packaging materials.
- Whenever you change the process used to make a product.
- Whenever you introduce a new piece of manufacturing equipment to produce the food product.
- Whenever you change the pack size of the finished product.
Best before date or use by date?
The determination to show your food expiry date as a “best-before” or a “use-by” date is generally governed by food safety legislation. As a rule of thumb, a “best-before” date will relate to the deterioration of quality attributes like colour, taste or freshness. A “use-by” date will generally relate to the food safety of the product. This indicates that for health and safety reasons, the product should not be eaten by the consumer. Check your local food labelling legislation to see if both use-by date and best-before date have been clearly defined.
Share your thoughts
How have you established and verified food product expiry dates in your business? Share your methods with the HACCP Mentor community by leaving a comment below this post.
