Science of smoking a sausage on the barbecue

Ever compared how a sausage comes out after grilling, frying in a frying pan or ‘steaming’ in a little bit of water? They probably all turned out very differently! The steamed version will have probably resulted in a very moist and tender sausage whereas the grilled version is somewhat drier, but has a lot more caramelization on the outside.

Every method turns out differently and if you’ve ever smoked your sausages you will know it will again turn out different. The skin of a smoked sausage might be somewhat crispier, the colour of the inside might be slightly more pink (even when it’s cooked through) and the overall taste is just different.

Since smoking changes the product so much, it deserves a more extensive evaluation.

What is smoking of food?

Smoking really doesn’t consist of more than leaving your product (in this case a sausage) in an area filled with smoke for a while. In most cases that smoke is created by burning wood.

Smoking can be done both warm and cold. In the case of warm smoking (as we’ll do for the sausage in this post) the product lies above or in the same chamber as where the smoke is made. If smoking a product cold the smoke is created in a different chamber and is then led to the product. A product that’s been smoked cold is not cooked whereas a warm smoked product can be cooked through simultaneously.

Why smoke food?

Reasons for smoking can be diverse. Smoking has been used for centuries to conserve products. One way smoke preserves food is through its low pH value. Smoke is quite acidic and the components that cause this acidity will sit on the food. Since micro organisms don’t tend to grow well at a low pH, this reduces spoilage. Another advantage is that smoke slows down rancidity in foods.

Besides conservation though, smoke can also be used to obtain a certain flavour or texture, which is why we’re smoking the sausage in this post. Smoke contains a lot of flavour components and by entering your food the food will also get these flavours. It will also change the texture, for example by drying out the surface slightly.

Hot smoking sausage – time vs. quality

When hot smoking a raw pork sausage, for immediate consumption. There are two things you’d want to happen:

• The sausage should be cooked through; especially when using pork or chicken the meat should be fully cooked
• The sausage should be smoked to develop that flavour and texture.

Since you want both outcomes to be successful there’s always an interplay between them. On the one hand you want to make sure the meat is cooked and for that the temperature should be sufficiently high to do so. Pork tends to be cooked at temperatures over 70C so if you want to smoke and cook at the same time you should at least reach that temperature.

But raising the temperature very high will cook the pork very fast. As a result, it will only be in the smoke for a short amount of time, whereas you’d prefer a slightly longer time to give smoke the chance to properly enter the meat. At these high temperatures you wouldn’t want the pork to stay too long since it will dry out the sausage and decrease quality.

A crispy skin

By cooking the sausage slowly you will give water ample time to leave the meat. Especially moisture at the sides will get to evaporate. This is what helps in getting that crispy skin, a characteristic for smoked sausages.

A pink ring in meat after smoking

An interesting thing about smoking meat is that the meat might not look cooked when it comes out. Instead of being a light brown, the meat will have a pinkish ring on the outside.

The colour of uncooked red meats can be purple, red or even brownish. Once the meat is cooked it tends to colour brown. Colour is often used as an indicator as to whether meat has been properly cooked and is ready to heat. However, in this case that doesn’t work.

For uncured meats (like the fresh sausage earlier in this post) this is due to a reaction of the myoglobin (the colour molecule in meat) with nitrogen dioxide gas (NO₂). This gas can be formed during smoking, but also from charcoal or gas. The nitrogen dioxide gas will dissolve in the meat and react, ultimately forming nitric oxide (NO). This nitric oxide can react with myoglobin, forming a stable pink colour molecule.

Checking the casing before smoking

Sausages will always have some sort of casing around the filling to keep everything together. These casing can be natural, in that case they’re often sheep or pork intestines, but they can also be artificial. Whereas most natural casings are suited for smoking, not all artificial casing are. When smoking a product it is important that the smoke can actually penetrate through the casing into the meat. Else the smoke won’t be able to interact with the meat itself.

Slow(er) smoking of a sausage on the barbecue

So let’s have a look at smoking a sausage on the barbecue. First of all you need a way to make smoke, this can be done by adding some wood to the charcoal. This doesn’t have to be a lot of wood and there are a lot of different types of wood which will each give a slightly different flavour profile. Woodcraft digs deeper into deciding which wood type to pick for your smoking challenge.

Second you will need an enclosed chamber to make sure the smoke doesn’t float away. Then of course you’ll need your sausage. Since we don’t want it to cook too fast it’s best not to place it straight above the heat. Instead, place it on the other side of the chamber where the heat is somewhat reduced.

Sources

For Dutch speaking readers, a pretty complete guide on smoking.