Food preservation was extremely important in ancient and medieval times. They didn’t have refrigerators or artificial preservatives; any excess produce was preserved both to prevent waste and try and ensure a continuous food supply.
When you’re preserving, you’re attempting to prevent food spoilage from starting – once food has started to spoil, pretty much all you can do is throw it out. Food spoilage is caused by harmful bacteria. Like most organisms, bacteria require certain essentials to grow – a food supply, and a comfortable environment; most also prefer a moist environment. Some harmful bacteria also require oxygen, but one of the most dangerous organisms, botulism, prefers an anaerobic, or oxygen-poor, environment. Essentially, when you’re preserving, you are creating an environment that’s hostile to bacteria.
Salting is one of the oldest food preservation methods, and is still used today in the production of gourmet meats such as prosciutto (ham) and gravlax (salmon). It works by drawing out the moisture from food, which sees off most bacteria, and prevents the growth of botulism, which doesn’t like a highly saline environment. When used with meat, salt also reacts with enzymes in the meat to change its chemical structure, breaking down the fibres and tenderising the meat. (McGee, 2004, 174).
In medieval times, food spoilage was considered to be caused by an excess of cold, wet humours. So to preserve food, you had to drastically increase the hot, dry humours. According to Platina, “the virtue of salt is fiery so that it contracts, dries and binds whatever bodies it touches. If dead flesh is salted in time, it is very well preserved.” (Scully, 1995, 55).
So now we’ve got all the boring science out of the way, let’s get down to the meat of the matter.
Method of curing hams and Puteolan ofella
You should salt hams in the following manner, in a jar or large pot: When you have bought the hams cut off the hocks. Allow a half-modius of ground Roman salt to each ham. Spread salt on the bottom of the jar or pot; then lay a ham, with the skin facing downwards, and cover the whole with salt. Place another ham over it and cover in the same way, taking care that meat does not touch meat. Continue in the same way until all are covered. When you have arranged them all, spread salt above so that the meat shall not show, and level the whole. When they have remained five days in the salt remove them all with their own salt. Place at the bottom those which had been on top before, covering and arranging them as before. Twelve days later take them out finally, brush off all the salt, and hang them for two days in a draught. On the third day clean them thoroughly with a sponge and rub with oil. Hang them in smoke for two days, and the third day take them down, rub with a mixture of oil and vinegar, and hang in the meat-house. No moths or worms will touch them.
Cato, De Agri Cultura (On Farming), 127.
The above recipe comes from a work on farming written by Marcus Porcius Cato (Cato the Censor) in C2 BC. At a time when Rome was expanding and coming into contact with other cultures, Cato was very eager to preserve what he saw as traditional Roman values, which is probably why he wrote a book about how to run a farm. It was a highly influential work and was used as a blueprint for farm management for decades after.
Even though this recipe is over 2,000 years old, the process hasn’t really changed. The following process is adapted from Australian chef Adrian Richardson’s Meat – “Dry Cure Mix for the Enthusiast,” p 244. All I have done is change the spices to be spices available in the medieval period. I prepared this for Spring War 2013, where I wanted enough that 200 or so people would be able to have a taste.
|4 kg pork belly, boned||100 g ground pepper|
|2kg Preserving salt (see Notes)||100g ground fennel seeds|
The starting point. At this stage, the pork belly is pink and moist, and very soft.
- Slice the pork belly into roughly equal pieces.
- Mix the salt and the spices together. Have your main preserving mix in one container, and then put some into a separate bowl before beginning the next step.
- Work a generous handful of the mix into each piece of pork, then stack them on top of each other in a non-reactive bowl (glass, plastic or ceramic – not metal), putting skin to skin and flesh to flesh. The first piece should be skin side down. Cover the container and put in a cool place – the fridge is ideal, and won’t interfere with the salt’s action.
Pork belly stacked after first salting. You can see moisture already starting to pool on the meat.
The pork belly after 24 hours. As you can see, the salt has largely dissolved into the flesh, and there is a lot of liquid in the bottom of the container.
- After 24 hours, drain off the liquid, then rinse and dry the bowl. Rub a fresh handful of curing mix into each piece of pork, then stack back into the container in the opposite order (so the one on the bottom is now on top).
- Repeat this process every 24 hours for 5-8 days. You will know the process is complete when there’s very little liquid in the bottom of the container. You can expect to lose as much as 10% of liquid from your pork belly. The liquid will be extremely salty – it makes an excellent weed killer.
- Rinse and dry the pieces well, and store in a cool place – again, the fridge is good. It will keep for around 6 months.
The finished product. There is some staining from the pepper, but the meat has darkened considerably and has become very leathery in texture.
- The meat will now be really salty – too salty to eat. Before eating, slice the meat into strips, and then soak for at least 12 hours, preferably changing the water once. Drain and dry well, and fry as you would normal bacon.
- Finding the right salt for preserving can be tricky. Modern table salt has anti-caking agents added to stop it from clumping; you also find salt sometimes has extra iodine added. Both will interfere with the preserving. Iodine actually destroys the enzymes in the meat that help to break down the fibres. If you can’t find salt that doesn’t have additives, get some rock salt and crush it.
- These are just the spices I used. You could also use mustard, cinnamon or cloves, or add dried herbs such as rosemary or thyme.
- The spices have very little to do with the preservation process – they simply add flavour. However, oily spices such as cloves and cinnamon do have antiseptic properties which help can stop the growth of bacteria.
McGee, Harold. On Food and Cooking. New York: Scribner, 2004.
Scully, Terence. The Art of Cookery in the Middle Ages. Woodbridge: Boydell Press, 1995.