The Mystery of what Goes into Sausages

The maxim "we'll never know unless we try" seems to have been enthusiastically accepted by the people who make our food. It's behind everything from cheese in a spray can to mineral water that's black as ink (really).

But sausages of all kinds are a particular playground – within that smooth casing, all manner of interesting substances can be squeezed. And not just unsavoury odds and ends of the animal like gristle and offal, although those are certainly present. Traditionally, sausages have sported extras like rice, cabbage, orange zest, animal blood, cassava, potatoes, and bananas, as well as a rainbow of spices, such as paprika, which gives chorizo its kick, or fennel, which seasons Italian finocchiona.

It’s not always about flavour either: wheat flour, bread crumbs, a crowd of soybean products, and carrageenan, a seaweed gum for binding that's also used in ice cream, all make appearances in modern primers on sausage-making. These additions make the meat go farther or help achieve a certain texture.

Finally, to adjust the nutritional profile, researchers have subbed in everything from walnuts to crushed tomatoes to freeze-dried kimchi in the meat batter.

Into this gallery of sausage additives now steps glasswort, a plant you may never heard of that has nevertheless been seriously studied as something to add to hot dogs. Glassworts as a group have had a long and interesting career outside of food additives. The name refers to several different groups of tidal plants that look a bit like tiny pickles stacked end-to-end. One type of glasswort played a prominent role in the glass industry in England as a source for sodium oxide, or soda. Just on their own, many glassworts are edible, and you might see them on the menu as sea beans or samphire.

A question of texture

But in a paper published in the journal Meat Science, a team of Korean scientists looked into a different kind of glasswort eating: as a way to reduce the amount of added salt in hot dogs. Taking salt out of sausages isn't simple – it turns out to be key to their structural integrity. But glasswort plants are naturally very salty, absorbing it from the salt water they live near, and they might bring other nutritional perks, including a bit of fibre. The team manufactured several different combinations, including control hot dogs with 1.5% salt, 0.75% salt, and hybrid dogs with 0.75% salt plus various fractions of powdered glasswort.

Now, a hot-dog style sausage is a technically very impressive thing. That even-textured interior consists of a mesh of protein strands with globules of fat caught between them. The more proteins removed from the mixture of minced lean meat and fat that goes into hot dogs, the more consistent the texture will be.

Some of those proteins are soluble in water, which is why, in addition to meat, these sausages always have crushed ice as an ingredient (and it's ice, not water, because if the mixture gets too warm, the fat droplets find their way to each other and make big, unattractive islands of fat in the sausage). Some of the proteins are only soluble in the presence of salt, however. That means that salt is not just a flavouring – it's a key part of ensuring that the hot dog holds together.

Texture, as you can see, is a very delicate proposition in these kinds of sausages, and salt is part of it. Other researchers who've added walnuts to sausages and then tried to cut salt have found themselves experimenting with enzymes and other additives to try to get the texture back to normal. Researchers trying to sub in a vegetable gel for fat, and a seaweed called sea spaghetti for salt – each of which has had some success individually – found to their surprise that sausages that had both were sub-par, leaking far too much water in cooking. Replacing salt, it turns out, is a lot more complicated than it might first appear.

Taste test?

So after the Korean researchers had made their hot dogs, they put their creations through a battery of chemical and physical tests to see how well they gelled when glasswort, rather than added salt, was in the mix. A truly astonishing number of lab gadgets were unleashed on the hapless dogs, and they were tested on hardness, springiness, cohesiveness, gumminess, and chewiness, all important and traditional measures of sausage texture.

The verdict? Glasswort does manage to pull down some of those salt-soluble proteins, and the more glasswort was in the sausage, the more salt-soluble proteins were in play. But it did not quite measure up to the power of added salt.

The researchers say that this is not necessarily a deal-breaker, and more experiments should be run to see how glasswort handles itself in hot dogs. But a key omission from this study, from the perspective of a potential glasswort hot dog eater, is what they taste like. It's not a foregone conclusion that they would taste strange. After all, some very delicious sausages are traditionally made with large helpings of vegetables in them – a particularly delicious way of getting some of your five a day, some might think…