Stability and Shelf Life of Ambroxan (Neat Form vs. 10% Dilution in DPG)

Regarding your questions about the shelf life and stability of Ambroxan, here is the detailed information:

1. Does the expiration date mean true degradation?

In the fragrance industry, the expiration date (in your case, 2026-07-17) is typically a "Re-test Date" rather than a hard expiration. It does not mean the material will suddenly degrade or become unusable on that day.

• Ambroxan is a highly stable cyclic ether. Unlike aldehydes or citrus oils, it is not highly prone to rapid oxidation or polymerization.
• If stored correctly (cool, dark, airtight), Ambroxan can often remain stable and maintain its olfactory profile for several years beyond the official shelf life. After the date passes, the material should be evaluated by smell and appearance (checking for off-odors or significant discoloration).

2. Shelf Life: Neat Form (Crystals)

The official shelf life for Ambroxan is 24 months from the date of manufacture.

• Expected Longevity: In its neat (pure crystal) form, if kept in a sealed container away from heat and light, it is one of the most "hardy" aroma chemicals. It is common for professional perfumers to use high-quality Ambroxan for 3–5 years if the storage conditions are optimal.

3. Shelf Life: 10% Dilution in Dipropylene Glycol (DPG)

When you dilute Ambroxan in Dipropylene glycol, the shelf life generally follows the original expiration of the raw material, but there are a few factors to consider:

• Solvent Stability: Dipropylene glycol is a very stable solvent and does not oxidize easily. It acts as a good carrier that helps preserve the molecule.
• Exposure: The process of diluting involves exposing the material to air and potentially light. Once diluted, the "clock" for the mixture usually aligns with the remaining shelf life of the Ambroxan used.
• Expected Longevity: A 10% dilution in DPG should easily last until the 2026 date and likely 1–2 years beyond, provided it is stored in a glass bottle (preferably amber) with minimal headspace (the air gap at the top of the bottle).

Summary of Storage Recommendations

To maximize the life of both your neat and diluted Ambroxan:

• Temperature: Store in a cool place (15-25°C). Avoid frequent temperature fluctuations.
• Light: Keep in total darkness or in amber/cobalt glass bottles. UV light is the primary enemy of aroma chemicals.
• Air: Keep bottles tightly sealed. For dilutions, if you have a large bottle that is only half full, consider transferring it to a smaller bottle to reduce the amount of oxygen in contact with the liquid.