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What do you think the dish at the top of this photo consists of? Looks like chicken with rice to you? It does so to me as well! However, it is ‘chicken’, but, it’s vegetarian…
Most of us know: we should eat less meat. Whereas I don’t have any problems eating vegetarian regularly, not everyone in our or your household might think the same. So besides the regular vegetarian meals (paneer is a favorite!) in which we simply don’t eat meat (nor a meat replacer), we eat meat replacers once in a while.
This vegetarian ‘chicken’ with rice dish is just one example. Nowadays, there are so many vegetarian meats on the market, even burgers that cook, look and eat like beef burgers! These vegetarian meats aren’t really meats anymore, they’re not made of the muscle of an animal. But how do manufactures nowadays make these vegetarian chicken equivalents that do look surprisingly much like chicken? A food scientist will tell you that the structure and texture of meat is quite unique and not easy to replicate without an animal that grows this meat. So how can you do it?
De Vegetarische Slager
The vegetarian chicken you see on the photo above is made by ‘De Vegetarische Slager‘. This Dutch company was founded by a farmer who decided to go vegetarian but missed his meat too much. Instead of turning back to eating meat, he decided to develop a vegetarian version of meat. His challenge: creating that characteristic bite and taste of meat, without using any animals.
In my experience, it’s one of the best vegetarian chickens out there. The texture is really close to that of real chicken. The success of their brand (Which has been growing tremendously in the past year) is proof of that as well. But they are definitely not the only ones out there any more. There are a lot of different manufacturers, so how do they do it?
The challenges of making vegetarian chicken
Meat is pretty special. The muscles that we like to eat need to do work while the animal is alive. This impacts their texture and flavour (can be positive & negative). These muscles consist of nicely aligned and bundled muscle fibers. This structure is what gives meat its unique bite and texture. It can be juicy and tender, while still firm. Compare the texture of meat to that of vegetables and fruit and you’ll notice it is very different. This is also what makes meat so hard to replicate well.
The other challenge is to get that flavour of meat into your vegetarian chicken. Meat contains all sorts of flavour molecules and when you prepare the meat these flavours continue to develop. It isn’t just one flavour molecule that you can replace, instead, it’s a whole mixture of them.
Apart from getting those sensorial experiences right, you also want consumer to experience the cooking of the ‘chicken’ in the ‘right’ way. You want to be sure your consumers can prepare the product in a very similar way as they would do with meat. This sounds easy, however, most of the chemical conversions that take place when cooking meat occur in a very narrow time and temperature spectrum. Finding proteins, and other ingredients that convert in the same way as a raw chicken would isn’t easy.
Raw vs. Pre-cooked
There are two ways to try and get this vegetarian chicken right. One, you can just pre-cook the vegetarian chicken product and focus on getting that end product look like the ‘real’ thing. This eliminates the hassle of trying to make a product that behaves like a ‘raw’ chicken would.
The other option is to make something raw, that looks likechicken and also looks like cooked chicken once a consumer prepares it. This is definitely more challenging, since both the raw and the cooked product have to meet those consumers expectations!
This is why in the case of vegetarian chicken you will see a lot of pre-cooked products. You still need to heat them up, but the major transformations have already taken place. It is easier to make a product that matches a cooked chicken, than a product that matches both the raw & cooked version of chicken.
For vegetarian hamburgers you will find the opposite, producers are actually aiming to mimick the raw texture and look of a hamburger! As a result, these require even more science to make.
Some of these challenges are very similar to those that aise when trying to make plant-based fish products.
Main ingredients of vegetarian chicken
From here on we will focus on the pre-cooked chicken. Let’s first have a look at how you can mimic that texture of a piece of chicken. The muscle texture is formed mostly by proteins, with some interspersed fat and plenty of moisture. As a result, you will see most replacements finding alternative proteins to mimic this texture.
Soy base for vegetarian chicken
A majority of vegetarian chickens are made using soy proteins as a base. Soy is a common source of vegetable protein. Soy beans naturally contain a high amount of protein and manufacturers can isolate these proteins from the plants. No animals needed.
Soy beans grow on plants and are known for their high protein contents. That makes up for the protein content of the vegetarian chicken. However, since soy is a vegetable, and not meat, it has a completely different structure. If you’ve eaten soy beans you will know what I’m referring to. Therefore, to transform these soy proteins you will need to process the proteins further to align them just as nicely as a muscle fiber.
Another common ingredient to mimic chicken, is branded as Quorn. Quorn products are made with mycoprotein. Mycoprotein is a protein source that comes from fungi (so it’s related to mould and yeasts). Quorn has large fermentation vats in which they grow a specific type of fungi: fusarium venenatum. By feeding this fungi the right types of minerals, vitamins, etc. they will grow well and can be harvested to make the required mycoprotein.
They can transform the mycoprotein into vegetarian meats by steaming the mycoprotein for an extended amount of time. The heat and moisture will cause it to form a sturdy texture. It is then frozen which improves the binding even further and is ready for sale afterwards.
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Mimicking chicken’s texture: ‘Shaping’ the (soy) proteins into ‘muscles’
Even though soy proteins contain a lot of protein, that doesn’t mean they behave like meat. Instead, they have to be shaped into fibers to imitate that muscle structure. There currently exist two major technologies to align soy proteins into a meat-like structure (and probably more, which are kept more secret). both methods have in common that they try to unfold the proteins and susequently aling them. Normally, these soy proteins are folded up into complex 3D structures. By placing the protein in sufficient water (hydration) it will unfold slightly, heating and mixing the proteins will unfold the protein more completely. Enough heat can then ‘fix’ the protein in its new 3D conformation.
The first commonly mentioned process for doing this uses an extruder. An extruder is an industrial piece of equipment. It consists of one or two large screws within a pipe. These screws move the ingredients through the pipe, continuoulsy moving product towards the exit. While the ingredients are within the extruder that are mixed and kneaded intensely. By controlling the temperature of the extruder along the length of the extruder, manufacturers can decide how and if to cook the ingredients within. Once the material comes out of the extruder, it’s cooked and ready to pack.
2. Shear cell technology
Shear cell technology sounds pretty daunting but it’s simpler than it sounds. Again, the technology, which has been developed by researchers at Wageningen University, aims to align the fibers of the plant (soy) proteins to create that muscle structure. They found that by using shear in one continuous direction they could align the proteins to form that muscle-like structure. By heating the proteins this alignment is fixated, they won’t move into another position anymore, even when they leave the mixer.
Extruders are known to require a lot of energy for running. This technology claims to be a lot less energy intensive. Instead of pushing the material through the extruder, the proteins are placed in between to rotating walls. These two walls will start to rotate and do so for a set amount of time.
Whether the technology is being commercialized already isn’t clear, but who knows what products may already be made using this technology!
Mimicking the flavour of chicken
Soy protein doesn’t naturally taste like chicken, it tastes like soy. so once you’ve managed to create the right chicken texture with the right amount of bite and moisture, it’s time to add some flavour.
If you’ve ever looked at the label of a vegetarian chicken product you will have noticed that the list of ingredients is quite long and that a lot of it are flavours. A common ingredient you will find is yeast extract. Yeast extract is used to flavour broths and stocks and has a savoury flavour, making it a suitable ingredient for vegetarian chicken. you will also find onion, garlic, salt and pepper as common ingredients here, all designed to strengthen and add flavour. The sugar helps to sweeten the chicken, but also it helps it to brown when you’re searing it off (thanks to the Maillard reaction).
Replacing a whole chicken
You might have noticed that most vegetarian chicken products try to replicate meats made from the chicken breast. This is actually one of the more bland parts of the chicken. A lot of the flavour actually sits in the more fatty chicken parts as well as the bones. Finding a replacement for a whole chicken will be a whole different story. Your best option is to use vegetarian stock maybe with some of those vegetarian chicken fillets.
So, there I was, with my vegetarian chicken, probably made using some sort of extrusion process with a lot of soy. But that’s just part of the question. Most interesting, how did they taste? Well, surprisingly good! I heated some satay sauce (which I tend to eat with my chicken and rice) and dipped the veggie chicken in. It might have lacked a little flavour if baked just so, but with some spices or sauce (as you would normally prepare your chicken as well) it tasted good! I wouldn’t hesitate using it more often. But then, I could also make that same dish without any meat (replacer) and it would probably still taste good.
Also wondering what is really the most sustainable ‘chicken’? Unfortunately, these questions and thus the answers will always be complicated, we took a stab at it.
Heselmans, Marianne, Eindelijk: een vegetarische bieflap die goed is, 2-Nov-2015, link
VK Joshi, Kumar, S., Meat analogues: plant based alternatives to meat products: a review, Int. J. Food Ferment. Technology, 5(2): 107-119, Dec 2015, link
Quorn, How is mycoprotein made?, visited July-2019, link
Wageningen University, Biefstuk van plantaardige eiwitten, 21-Oct-2015, link