In the Middle Ages, animal milk was, of course, not refrigerated, and fresh milk did not stay fresh for long.
Street Sellers of milk at the time often sold milk which had been diluted with water, or that was already spoiled.

Any milk sold or brought at the stalls was typically that of from Goats as it lasted longer then Cow's milk and could be drunk even after it had spoiled with little difference in taste.

Many medieval recipes of the era did not rely on milk and with the cost of trying to get a fresh supply it was usually only the rich who could afford such a luxury.

Although many farmers would as well if they kept a bucket for themselves when milking their animals.

A substitute that could be made on an when needed basis in any quantity, although very high in natural fat was Almond Milk.

This substitute could be found in a number of kitchens even in the poorer homes as a festive luxury as it cost hardly anything, although for some buying the almonds would have been a weeks worth of work.

Typically, Milk from Cows and Goats, when spoiled would be churned to make Butter as another luxury for those who could afford it - However Almond milk, because of it's high fat content could also be churned and many merchants used this as a method to reduce their costs for a higher profit.

Modern Almond Milk Recipe:
Yields approximately two Cups.

• 1 cup ground almonds
• 2 cups boiling water

- Combine almonds and water.
- Steep for 5 minutes, stirring occasionally.
- Sieve the mixture to remove coarse grains OR (preferably) blend mixture in electric blender until grains are absorbed.

In olden days use of a Sieve wasn't always available so those who drank the milk would often find themselves also drinking the grains.

• 1 medium sized cabbage
• 2 onions
• 3 leeks
• 8 to 10 saffron stems
• A knob of butter
• A good pinch of ground cinnamon
• ½ teaspoon of sugar
• 2 pints of good strong chicken stock
• Chopped parsley as a garnish
• Ground black pepper and salt to taste

Preparation:

Remove any damaged outer leaves from the cabbage and then cut the heart of the vegetable into eight pieces.

Discard any large chunks of hard stem to use only the leafy part of the vegetable.

Peel, halve and slice the onions to produce half onion rings.

Trim the leeks to remove the green leafy part leaving the firm white stem.

Thinly slice the white stems to make narrow ‘leek rings’.

Cooking:

Place the onions and the leeks in a big pot with a very small amount of butter. Heat very gently for about five minutes or until the vegetables soften and add black pepper to taste.

Grind the saffron stems in a pestle and mortar and add a little stock to dissolve the resulting saffron paste.

If you don’t have any stock to hand you can crumble two stock cubes into two pints of boiling water. Saffron will colour your stock a beautiful and very medieval yellow.

Stir the salt and the spices into the remaining stock and pour over the onions and leeks.

Add the saffron stock and stir thoroughly to make sure the saffron colours the soup evenly.

Add the cabbage and cover with a lid. Bring to a boil and then simmer gently until the cabbage is cooked and skim any residual fat from the top of the soup using a ladle.

Serve piping hot with a sprinkle of chopped parsley.

Source: History.com - Medieval Food