Crispness is one of the sensory attributes most appreciated by consumers. The intensity of this characteristic is used to measure the quality of many fried foods such as chicken nuggets, onion rings and breaded shrimp, for example.
To give crispness to these mentioned products, a coating system is used, which can be defined as any combination of ingredients, whether cereal based or not, which coats a protein substrate or one of other nature, giving the finished product attributes such as taste, texture and appearance.
In addition to the sensory aspect, the coating systems function as a barrier against gas migration and moisture loss or gain, as well as protecting foods from mechanical damage.
It is also a way to increase the variety of products and to add value to simpler foods. Breading is a popular coating system, ensuring all the features mentioned above.
Nowadays, actually, some breading systems may contain seasoning, further enhancing characteristics of taste, aroma and appearance.
Because of its industrial and economic importance, industries that work with breaded products or that are considering implementing this line in their portfolio need to have knowledge about the process and types of breading available.
One should also be aware of the particularities of the ingredients involved, especially with regards to breadcrumbs. These mentioned topics will be the subject of this blog post. Check it out!
Preparing breaded products
Legislation defines breaded products as any industrialized meat product obtained from meat of different species of butcher animals, with ingredients molded or not, and revised with appropriate coat that characterizes it.
The maximum percentages for total fats are not defined in the normatives.
When producing a breaded product, it should be taken into consideration substrate characteristics, such as water content, shape, size, temperature, texture, nutritional composition, surface type and adhesion potential.
Some operations should be conducted during the production of these foods, such as:
- Size reduction: decrease in hardness and increase in surface area.
- Mixture of ingredients: increase of the surface area and rupture of the muscle fiber, favoring the release of intracellular components.
- Molding: pressing the dough into a desired mold. It is performed at high pressures and with the product previously frozen to achieve the desired shape.
- Coating by the coating system: application of the breading system. It usually involves three steps - predust, batter and breading.
- Frying: product dip in oil, at high temperatures (180-200 °C) for a short period of time (20 to 35 seconds). During this process, the coating is fixed, there is development of color, reduction of moisture, inhibition of product dehydration by cold and oil absorption.
- Cooking: product can be cooked under steam or heat only. In some cases this step can be eliminated.
- Freezing: promoting rapid freezing is ideal for a uniform texture of the product, without ice crystals perceptible to the palate. It is usually performed at -18 °C.
Of the whole process of formulating a breaded product, certainly the central step is breading. This operation involves three fundamental steps:
This is the first component of a coating system and it has as an objective the bond between the substrate and the batter. In many cases it will also be a seasoning carrier. Due to the uneven surface of the foods, the coat and substrate may encounter problems of adhesion.
The predust will be the one responsible for eliminating this problem, with the formation of an absorbent layer, which will give greater uniformity and better texture.
Wheat flour is the predust most used by the industry, but there are also other alternatives of predust formulation, with starch and protein.
These alternatives can be used to eliminate some disadvantages presented by wheat flour, such as detachment of the coating and loss of crispness, due to the formation of a film between the coating and the meat, leaving the moisture trapped, which increases the pressure below the coating, resulting in its displacement.
Consisting of a powder mixture of various ingredients, the batter may contain seasonings or not. When hydrated, it forms a suspension of solids in liquid, which works as an outer coating layer for the food, and also makes the adhesion between the substrate and the breading, the outermost layer.
The most common ingredients of batter are wheat flour, cornmeal, starch, gums, darkening agents, proteins and flavorings.
Wheat flour provides viscosity, helps in the suspension of some solid ingredients and assists in obtaining a firm texture in the coating. They can be hard or soft, which will be defined by the content of protein produced.
Hard ones produce 11% or more of proteins with a good quality of gluten properties. While the soft ones contribute with a protein content of 7 to 9%, with low quality of gluten properties.
On the other hand, cornmeal does not have the capacity to develop gluten. In addition, it differs from wheat flour because it does not present the same capacity of water absorption and because it has a greater grain size.
Starches, however, promote greater adhesion and a better property of film-forming in relation to meals. The function of gums, when present in a batter formulation, is to ensure viscosity, stability and homogeneity.
Darkening agents, as the name implies, are used to develop coloration by applying heat. It may be used dextrose, sucrose and some dairy ingredients.
The proteins most used in batter are of soy, milk and eggs, as well as wheat gluten. They contribute to an improvement in properties of emulsion, film formation, darkening, adhesion and texture.
Flavorings may come in the form of spices and salt. This last one can even be used to prevent the formation of ice crystals when the batter is at low temperatures.
Depending on the degree of viscosity, batters can be classified as adhesion (low), cohesion (medium) and tempura (high). This last one is generally used for derivatives of fish, seafood, chicken and vegetables.
Breading or Crumb
Breading is the topping meal, which may be cereal based and contain seasonings or not. This term encompasses a variety of products, from wheat flour untempered and uncooked to breadcrumbs. It is the layer applied over the batter.
Breading can be thick (higher visual impact), medium (better water absorption) or thin (rapid water absorption).
There are four varieties of breading available:
Traditional: a dense meal with some crusts, which provides a hard bite;
Extruded: that presents crispness similar to breadcrumbs and can be produced on a large scale;
American: that provides a crispy bite with pieces of rounded crust;
Japanese: that has an elongated shape and is free of crust, in addition to being the most crunchy of all kinds.
Breading: visual appeal and crispness
By being the most outer layer and visually attractive, breading directly influences the acceptance of breaded products.
Therefore, it is important that this step is conducted very carefully and that the proper process and ingredients are chosen to compose it.
The extrusion process stands out for this purpose, by being economically viable and flexible. In addition to producing breadcrumbs, it is commonly used for cereal processing, modified starch, cheese analogues and infant formulas.
A study evaluated the production of breading by extrusion, consisting of wheat flour, cornmeal and soy meal for the breading of chicken nuggets.
The authors observed that the use of an extrusion process with high temperature (120 °C) and low humidity (27%) produced crumbs with good functionality and crispness, as well as greater acceptance by consumers when compared to other formulation types.
Another study, using breadcrumbs for breading also attested to the effectiveness of the extrusion process.
Crumbs produced by this method presented lower humidity, higher density, oil absorption and capacity of water absorption than crumbs produced in a conventional oven. In addition, the extruded crumbs also had greater sensory acceptance mainly for taste and odor aspects.
Breaded products are very popular among consumers because of aspects as texture, taste and unmistakable appearance, as well as practicality.
The breading process involves different steps that need to be conducted carefully and with the right choice of ingredients and processes to obtain high quality products.
The extrusion process has proved to be an interesting alternative for the production of breadcrumbs that present good functional characteristics and acceptance among consumers.