The short answer to this question is – yes, and no. For dry brewing yeast, then yes – it can safely be shipped without any sort of cooling required. For liquid yeast, it depends on the shipping method used and the climate it is shipped in.
Shipping Dry Brewing Yeast
Shipping dry brewing yeast even in warmer temperatures will not affect its viability as long as it doesn’t spend more than a few weeks out of the fridge.
Lallemand themselves say dry yeast is very stable and some exposure to moderate heat will not significantly impact performance. Don’t be surprised if your yeast is delivered without an ice pack, this is normal. After all, the viable cells in the package have already survived some heat exposure during the drying process.” You can see this info in one of their info documents here.
Fermentis also mention that the product must be stored below 24°C. For more than 6 months: the product must be stored below 15°C. For short periods not exceeding 7 days there is an exception to these rules. Although, I would say that they are being very conservative here.
Almost all the online stores you buy yeast from will ship it without any sort of ice packs or cooling. This is totally normal and your yeast will be fine. Just throw it in the fridge when it arrives.
If you want to be sure that your yeast spends the least possible time out of the fridge, then choose an express shipping option when you order from us.
Shipping Liquid Yeast
Shipping liquid homebrew yeast in warmer temperatures can be a bit tricky, but it’s definitely doable. Most liquid yeast will ship fine even without ice packs assuming its back in the fridge within a few days.
If a longer transit is required, or the climate is quite warm then you can do the following:
- Use insulated packaging: Use insulated packaging such as Styrofoam or a vacuum insulated container to keep the yeast cool during transit.
- Add ice packs: Adding ice packs to the package can also help keep the yeast cool. Make sure to wrap the ice packs in plastic to prevent any leakage.
- Ship overnight: If possible, ship the yeast overnight to minimize the amount of time it spends in transit.
- Choose the right shipping method: Choose a shipping method that guarantees delivery within one or two days, such as express post or shipping.
- Label the package as containing live yeast: Keep a good communication with the carrier and make sure they are aware of the package being shipped as yeast.
Remember, yeast is a living organism and it can be affected by high temperatures, so it’s important to take extra care to keep it cool during transit.
To learn more about the differences between dry yeast and liquid yeast, see this article.