Is all food we eat processed?
The answer to this question might turn upside down what many people thought about the processed food, its role in a healthy diet and impact on our well being. If we study how many products of our day-to-day diet are made, we will discover that almost every and each piece of food we put in a trolley while shopping is processed this way or another. In fact, a deeper and more inquisitive research will show in end that the myth of always harmful and unhealthy processed food that should be avoided is just as much – a myth. The truth lies in between good and bad, as this way of introducing food into the market has its good and bad sides. Not always is the processing bad – sometimes it does improve the quality of the product or removes the threat such as bacterias naturally coming with the products the customers are about to eat.
In most cases, however, it comes down to the efficiency and increasing the production done in the shortest time possible. Processing serves as a mean to provide the customers with the demanded amount of products they seek, without losing on time or quality differing from one piece to another. When everything is done by a machine, every single piece looks, smells and tastes the same – ensuring that none is better or worse than the other.
Old process of processing
In spite of the fact that processing itself sounds like a recent invention, is it older than expected. It is true that the first attempts of using the processing in massive production date back to late nineteenth century, when it was first used while making sausages. That was the time when the first food extruder was invented and put to use. The more advanced versions had been appearing throughout decades up to the present day, and so far the food extruder is one of the most basic machines that speed the process of production. Thanks to this kind of a device, a consumer receives products such as pasta, cereals, bread or rolls, snacks, baby food or pet food and many, many others. It is not uncommon to observe a food extruder when the machine is working, for example in a TV program, yet little of such materials do explain the exact way of how an extruder works. This article is meant to reveal how the extrusion process is usually happening.
Extrusion process in a nutshell
Most often, if a person witnesses an extruder at work, they observe a vague, half-liquid dough forced through a tube-like machine, from which a raw yet already shaped product falls out towards a conveyor belt or a container. This machine is what is called an extruder and it works thanks to the power of a rotating forces within the part known as a barrel. The extruder ends with a die or a perforated piece shaping the mixed ingredients. The process itself, however, is more complex than visually simple structure of the machine. It can still be described in a relatively simple way, as it can be seen below.
Step 1 – Preparation of the ingredients
In the very beginning, the most basic ingredients are prepared to go through an extruder; they are usually brought into a form of a powder or flour; within a part called a pre-conditioner, the basic ingredients are mixed with sugar, fat, water or other, specific for a product. This could be a food dye, salt or meat – depending on the final form of the product and what is it usually made of. Nor rarely do the ingredients affect the later form of the product – for example, the salt is known to serve as a helper in even spreading food dyes and to affect the food coloring.
Step 2 – Cooking
After the initial mixing of the ingredients, the cooking process begins yet back in the pre-conditioner. It is done in order to produce what is called an extrudate, which means – a mix of ingredients meant to pass through the extruder and eventually form pieces of food in the desired form, shape and size. It is usually done by injecting steam that helps to achieve smooth and partially cooked, dough-like product from which the final portions of food are to be produced.
Step 3 – Extrusion
The extrusion process is strictly connected to the machine that an extruder is; to simplify, it consists of three main pieces: a barrel, a screw, and a steamlock, and each of the pieces play an important part in the process of producing be it pasta, cereals, or other food.
In this stage, the mix of ingredients – extrudate – is pressed into a barrel within which a rotating, well-fitted screw is placed; it is this part that shapes the extrudate and pushes it down the stationary barrel, only so it is cut into portions by the blades at the end of this tube-like part.
In the same time, the rest of the cooking process is happening; because of the high pressure within the barrel, the extrudate filling it starts producing its own friction and heat, and by doing so, in the end it leaves the extruder as a product ready to be cooled or dried. It is not uncommon that during the extrusion process the extrudate changes its properties by emitting moisture and heat, and in the end, increasing in size – these changes are known as expansion ratio.
Effects
With the process of extrusion being explained, it is also important to list what else, aside of basic and visual changes, happens with the ingredients processed within the extruder. It turns out that scientists could list at least a few effects occurring in the process, such as removing natural toxins and microorganisms in the food, an increase of glycemic index, dissolving of vitamin A or proteins. Those results definitely serve as reasoning behind why food processing is considered harmful, yet in today’s world it certainly seems impossible to give up on means of massive food production.
