Importing malt for a small brewery: lead times, storage and moisture

Lead time is part of the recipe

Imported malt arrives weeks or months after you decide to buy it. Add production and booking time, sea freight, port clearance and delivery to your site. Order from the date you need it, not from the date you run out. A reliable method is to set a minimum stock level in weeks of brewing and place a new order when you fall to it, with a margin for delay.

A simple example: a brewery that mashes 400 kg of malt a week and sees a 12 week gap between order and delivery has 4,800 kg either on the water or in the store at all times. Add a safety stock of three or four weeks for late ships and customs holds. The reorder point is higher still. The number looks large until you count the cost of a brewery standing idle.

Look at shipping minimums. Many maltsters sell by the pallet or by the full container. A small brewery may want a few pallets at a time, which means working with a distributor or sharing a container with other breweries. Compare cost per kilogram landed at your door, not the price at the maltster's gate. Landed cost includes freight, insurance, import duty and local handling. Currency movements can change it between order and payment.

Paperwork and the certificate of analysis

Import rules vary by country, so ask your customs broker which documents are needed for grain. A plant-health (phytosanitary) certificate is commonly required for agricultural products. Ask the supplier for a certificate of analysis for each lot: moisture, extract, colour, protein, soluble nitrogen ratio, diastatic power and friability. Compare the numbers with what you ordered and keep them with the lot code. These numbers also help you adjust your mash if a lot differs from the last one.

Moisture is the enemy

Malt leaves the kiln at around 4 to 5 per cent moisture. It picks up moisture from humid air, faster in the tropics. Malt that climbs above about 6 per cent becomes soft and loses crush quality. The mill may smear it into flour instead of cracking the husk. Lautering suffers. Fully wet malt can mould or sprout.

Check moisture on arrival if you can. A cheap moisture meter for grain gives a rough figure. Better to send a sample to a lab at intervals. Keep a note of the first reading and compare it each month.

Container rain and receiving

Containers moved from cold to hot conditions can form condensation on the roof and walls, sometimes called container rain, which drips onto the bags. Ask for desiccant bags or ventilated containers if the route is long. Open the container as soon as it arrives. Inspect the bags for wet spots, torn corners and insects. Photograph any damage and tell the supplier and the insurer immediately, before you unload and mix lots. Pallets should come off the floor and away from walls to allow airflow.

Storage that works in heat

Store malt in a cool, dry, clean room, off the floor and away from walls. Keep the humidity below about 60 per cent if possible. A dehumidifier or air conditioner earns its running cost here. Seal opened bags with clips or move the malt into airtight bins and label each bin with the lot code and date. Keep specialty malts sealed, because crystal and roasted malts take up moisture too. Roasted malts that go slack lose their sharp edge.

Whole malt keeps for many months in good conditions. Milled malt does not. Crush only what you will mash that day, because milled grain absorbs moisture fast and stales. Pests such as weevils and grain moths love warm stores, so use sealed containers, clean spills at once and inspect regularly. Talk to a pest-control adviser about food-safe methods.

Use stock in the right order

First in, first out is a basic rule that fails if no one labels the stock. Mark delivery dates on every pallet and check them on brew day. Plan recipes to make use of older lots first and spread any differences in colour or extract across your brews rather than switching lots overnight. Sample each lot in a small test mash if you can.

If supply is uncertain, think about local alternatives such as sorghum and cassava in commercial brewing. For other ingredients, read hop freshness across long supply chains and yeast for a warm room.

Common questions

How long does malt last?

Whole malt kept cool and dry keeps for many months. Milled malt only lasts days, so crush on the day of the brew.

What moisture level is a problem?

Above about 6 per cent malt gets soft and crushes badly. Fresh malt is usually 4 to 5 per cent.

Do I need a certificate of analysis?

Yes. Ask the supplier for one for each lot and keep it with the lot code so you can adjust your mash when lots differ.

Can I share a container with other breweries?

Often yes, through a distributor or a group order. Compare the landed cost per kilogram with buying a few pallets locally.