Like cooking, brewing great beer is only possible with the best ingredients. Ingredients are often cheaper if purchased in bulk. Small frequent ordering is not only more expensive but impractical especially if purchasing online. Recipes will inevitably also lead to left overs ingredients. But don’t fear, stored correctly, most will keep for many months.
The main enemies of brewing ingredients are light, heat, moisture and oxygen. In order to maximise the shelf life of left overs, exposure to these elements need addressing.
Hops contain essential oils and acids contributing both flavour and aroma. Essential oils fade very quickly, especially when exposed to sunlight and oxygen. Therefore exposure needs to be minimised. Alpha and beta acids, when isomerised, provide bitterness. They are fairly stable but they also will deteriorate over time. Although this deterioration is inevitable it can be slowed.
Hops should always be supplied vacuum sealed in light barrier bags. If not, reject them. Once opened, they should be repacked and stored cold, even frozen. If you don’t have access to a vacuum packer fold the bag back down and seal with some tape. The aim is to minimise the oxygen in the bag. Some varieties will keep better than others but most can be stored for around a year or more if exposure to oxygen is minimal. You may need to adjust your recipe as the acids could be reduced and therefore less bitterness may be extracted.
Uncrushed malts are pretty stable. As long as they are kept away from high temps, moisture and insects they should keep for a few years without any special treatment.
Once malt has been crushed it’s more susceptible to air as the hull of the grain is no longer providing protection. Crushed malts should be stored in an airtight container, away from direct light and in a fairly cool environment. They should keep for at least 3 months although probably much longer. Roasted and crystal malts will be even easier to store as they have been dried further so should keep for even longer. If the malt smells stale or there are any signs of mould then bin it and purchase some fresh.
Dried malt extract will store well if kept away from oxygen and light. Once opened the pack needs to be resealed and stored somewhere dark as it will pick up moisture in the air very quickly.
Light and air will darker the malt and the extracts will start to break down over time. The extract will also become very sticky and almost molten if exposed to air for quite a short period. Refrigeration will help although it’s not necessary and the extract should keep for many months without it.
Liquid Malt extract has similar issues to dried. It can be difficult to repackage as it’s often supplied in tins so if you do have some left over, we recommend putting in a sterilised glass jar and keeping in the fridge. It will probably be okay for a few weeks but it will be best to use as soon as possible.
Dry yeast has a very long shelf life and is easy to store. Due to the drying process, the yeast is very stable and therefore just ambient storage temperature will be fine. You can refrigerate but do not freeze.
Liquid yeasts are a different matter. They will deteriorate fairly quickly, especially if not stored in the fridge. As the number of healthy, viable cells drops, it will be necessary to revitalise by preparing a yeast starter a few days in advance of brewing. It is also a good idea to always have a packet or two of dried yeast available as a backup in case of a liquid yeast not starting.
More information on using yeast can be found in an earlier blog post.
In summary if you handle your ingredients correctly there should be no reason not to be able to store and reuse in subsequent brews.