How Often Should Shelf-Life Testing Be Performed?

Hello,

How often are you doing shelf-life testing? When are you testing? I'm in a chocolate manufacturing plant and am trying to get a shelf-life testing schedule down but wanted to see what systems others are using. 

Thanks!

APC, Yeast & Mold is what we test for on an annual basis.  This is part of general testing on our finished products as the majority of testing outside of SL is done on the material inputs.  We are also a seasonal operation focusing on fall and holiday confections.  We test the prior years retain samples as a composite taking multiple samples from various production runs at the end of the best by dates.  

Many many years ago I used to work in confectionery and we'd do an accelerated protocol for new products but also retain samples for ongoing verification of the shelf life on existing products.  

I was always taught that you don't use your retains for shelf-life because the packaging matters.  Sometimes the size of the packaging also matters like if it's a large package that results in compression of the bottom product over time.  For my company's meat products, I've been having production package the right size for the micro tests to make it easier to send because the package size should NOT impact the shelf-life.  Then keep the storage the same or as close to the same as possible.  So you should have enough sets of product to test same day, and at minimum somewhere around 75%, 100%, 125% of the current shelf-life.  Run the tests that are listed in the product specification which could be sensory or lab tests.  Run some amount of micro tests for spoilage organisms like APC, Yeast & Mold, Lactobacillus or Pseudomonas.  You can keep duplicate sets so that there's an unopened, untouched sample for the micro lab.  

Back to size of packaging.  I used to test food chemicals.  We would save a pallet (1-2k lbs) of product.  I would cut open 50lb bags for samples and leave them on top of the other bags so that we could see the impact of the weight of the top bags.  For 400lb drums, I would re-use a drum, but it has to be resealed each time.  For 2000lb supersacks, I would reuse the same supersack and reseal it every time.  

In my previous job, they would have the line leader make short logs of meat so that the packaging was same but the size was less wasteful.  In my current role, I have production use the same type of packaging but simply adjust the weight of the individual pack.  

You always want at least 1 extra package incase something tests OOS so we can check again.  

Or as GMO stated, you can pay a food laboratory like EMSL to conduct an accelerated shelf-life study.  They usually hold the product at a warmer temperature to speed up the total duration.  

For food chemicals, we had 3-4 types of products on each line.  I would pick 1 product for each production line, and slowly rotate through the different products. For food, you would want to pick a product per HACCP plan or by similar ingredients or similar current shelf lives.  

I was always taught that you don't use your retains for shelf-life because the packaging matters.  

It was only used for verification, i.e. to look for gross defects indicative that the set point for life was incorrect when it was set at the start.

We had validated our own internal study and equipment for accelerating shelf life.  But good to know of a US lab that does it.