Screening is a mechanical process , often used in bakery and patisserie. In the food industry, screening is an indispensable process in the preparation of products, especially for those that are expected to be marketed, as it guarantees their quality.
What is screening?
Screening is a procedure that consists on filtering dry ingredients through a screen, also called a sieve or screening machine. Flours are the main ingredient that is usually screened, but it also applies to other dry ingredients, such as cinnamon, sugar or cocoa. Our screening machine for the food or pharmaceutical industry is the new Dynamic Screener.
Why is it important to screen ingredients before mixing them?
Screening is a necessary procedure to ensure that preparations are well prepared. Not doing it can cause the food to have a different texture or even impurities that make it less enjoyable.
In practical terms, there are three reasons why you should screen all ingredients before mixing them:
Avoid clumps and impurities.
Due to humidity, flours and other dry ingredients can clump together. When this happens and the ingredients are added without screening, the clumps persist in the mixture and are very difficult to remove by pressing hard.
In addition, this also filters out any impurities that the ingredients may have (by accident). For example, wheat husks, grains or corn straw in the flour, grains in the coffee mixture, among others.
Incorporates air molecules
When the small grains of dry ingredients separate, they leave spaces between them that are “filled” by small air molecules. These molecules bring oxygen to the mixture and increase the sponginess of the final product.
Makes integration between ingredients easier
Finally, just as the separation of the grains allows the small empty spaces to be occupied by air, they also allow better integration between ingredients.
This happens because, being separated, the dry ingredients are much better integrated with each other.
In addition, manufacturers must apply this method to produce the right amount of product and maintain adequate quality control of the result.
Screening can be accomplished by various methods. At the industrial level, different machines have been developed for this purpose. The most common ones can be by shaking, washing or back-and-forth screening.
However, the most commonly used in the kitchen are strainers. Some of these methods are mentioned below:
Sonic method: a vibration is generated with low vibration acoustic waves to make the particles pass through the screen without being trapped.
Mechanical method: several types of screening machines can be used in this method.
• Electromagnetic: these are machines with coils or electromagnets, which produce a three-dimensional vibration, in other words, the movements range from vertical to rotary in order to prevent the particles from being retained in the screen. Look Our Ranger Separator
• Tapping: these are machines that apply a vertical and lateral tapping. It is very similar to the manual method. This method is very noisy, so a special space is usually reserved for the machines that carry out this process.
• Orbital: applies both vertical and horizontal movement but without vibration, usually applied to round particle products.
Manual method: in this method, the person handling the strainer must ensure that it makes a back-and-forth movement with occasional tapping to prevent particles from being retained in the mesh. An example of the latter is applied in the home kitchen with common strainers, using the hands to execute the previously mentioned movements.