DIY herbal medicine & expiration dates.
Chloe wrote to us with questions about herb expiration dates: "I have packets of herbs I ordered online that I want to make tinctures out of. Dried lavender expires on March 2020, valerian root expires May 2020. What do these expiry dates mean when I make tinctures and how do they affect my shelf life of tinctures? Does it mean the tincture will spoil in Mar/May 2020? Would they be deemed inedible? After they expire, am I still able to make tinctures out of them? Or would it be not recommended?
Great questions, Chloe! Herbal quality is such an important topic. After all, your finished product is only as good as your starting ingredients.
HERE'S THE DEAL:
Manufacturers and bulk herb suppliers are required to include an expiration date on their products. The dates they choose are sometimes based on quality testing or, more often, an arbitrary amount of time that the supplier deems acceptable. Two years is a common time frame.
There are two main concerns in herbal quality that are relevant to your question: Contamination and degradation.
Herbs that have been properly dried and stored (away from dampness, heat and light) should be free of bacterial or fungal growth or other contaminants and thus would be safe to use for a long time in regards to contamination.
However, herbs degrade or decline in potency at different rates depending on the herb. For example, licorice root is extremely stable. Testing data shows that many of the important constituents in licorice remain stable for decades! It's an herb that I would feel comfortable using for many many years regardless of the expiration date. Aromatic plants, on the other hand, such as chamomile and lavender lose their potency rather quickly. Valerian is somewhere in the middle.
The good news is that you do not need a lab to determine the quality of your herbs! One of the best ways to assess the quality of dried herbal material is via a process called 'organoleptics' which simply means using your senses. Does the plant material look, smell and taste like it should? If so, then you can move forward and tincture it, regardless of the expiration date. The fresher and more vital the plant material, the more potent your tincture will be. So, tincturing freshly dried plant material is an excellent option.
Remember: tincturing is a method of extracting AND preserving herbs. A tincture that contains at least 25% alcohol is very stable in the sense that microbial contaminants such as bacteria and fungi will not grow there. So, they never "spoil." However, tinctures such as valerian root and cannabis, for example, do change over time as their constituents naturally break down or evolve into different chemical compounds. This is not dangerous and the only way to know if they still offer the same therapeutic benefit is to ingest them and observe the effectiveness for yourself.
For more information about diy tincturing, and some excellent resources on that process, check out this blog post I wrote in April of this year. Good luck!