Murat AKSOY Specialist Sales Engineer ABP Gıda San. Ltd. Şti.

“No matter what type of a production method the grain-based biscuit has, the primary component of biscuit is flour, in other words the wheat. For this reason, the biscuit producers must be sensitive towards the quality of the flour which is the raw material of biscuits. The physical structure, odor and color properties of tens of biscuit types are significant for the product popularity and thus, the main target of the producers is that when such components as nuts, chocolate and oil used to increase the product assortment are added into the product, the popularity of the products is not compromised.”

Biscuit is a food item which has been consumed since the 16th century and that is today produced on the fully-automated production lines. The grain-based biscuits are produced in different methods in different parts of the world. No matter what type of a production method it has, the primary component of the biscuit is flour, in other words the wheat. The physical structure, odor and color properties of tens of biscuit types are significant for the product popularity and thus, the main target of the producers is that when such components as nuts, chocolate and oil used to increase the product assortment are added into the product, the popularity of the products is not compromised. All in all, the biscuit producers must ensure that the foundation of the product is robust.

The wheat widely used in the production of flour for biscuits is Triticum Compactum which is one of the 3 wheat types that have an economic value in the world. Additionally, the wheat produced from Triticum Aestivum types which are suitable for the production of biscuits but primarily used at the bakery is also used in the production of flour. As the plantation of Triticum Compactum wheat is low in our country, the biscuit producers prefer the bread flours that are also suitable for the production of biscuits. This entails more attention for the quality of wheat and the producers require the suppliers to continually provide standardized flour.

Generally speaking, the sought-after characteristics of the flour for biscuits can be cited as follows: • Obtaining a homogeneous and uniform paste during the kneading, • Easy machinability and shapeability, • Prevention of unwanted cracks and fractures on the biscuits during baking and cooling, • Quick baking,

Ensuring all of these characteristics depends on the fact that the flour producers must choose the right raw material, that’s to say, the wheat and carry out the right method of production. What matters in the production process is the physical and chemical content of wheat and the resulting flour and the rheological properties during the production process.

The most important factor affecting the physical and processability quality of the biscuits are its chemical components and the interaction of these components to each other. The most important of these components are starch, protein and pentosans.

STARCH The effects of the starch that is the basic component of the flour vary according to the amount of damaged starch. Normally, 70-75% of the flour is starch. This rate may differ according to the varieties and environment. While kneading the dough, the starch mutually interacts with the water, protein, fat and other molecules in the flour and in particular, it plays a significant role in the structure of dough as filling material in gluten bonding. Starch damage depends on grinding properties and grain hardness. In hard wheat, starch is more susceptible to damage and therefore, the expected amount of damaged starch will be more. The damaged starch grain absorbs 4 times more water than undamaged starch. An excessive amount of damaged starch reduces the spread of biscuits. For this reason, it is very important for the biscuit producers to know the amount of damaged starch. Seasonal diversity or change of the wheat variety and the change in the amount of damaged starch resulting from the possible changes in the grinding diagram leave the producers in the lurch. The amount of damaged starch which can be measured colorimetrically and enzymatically can be measured in an amperometric manner within 10 minutes through advanced technological methods.

PROTEIN Protein is the source of gluten and it forms a three-dimensional gluten net by absorbing much water (more than 2 times its weight) during the kneading of the dough. This gluten bread net has a significant role on the viscoelastic properties of bread dough and hard biscuit dough. In this respect, gluten is wanted for the cream crackers and hard, sweet pastry products.

But protein dehydration in short biscuit dough is not sufficient for the formation of gluten nets. Gluten formation is also not desirable in such products. Although the amount of protein and gluten properties influence the texture of the product, it is not possible to give exact values about the quantities.

The general opinion is that the flour to be used in the production of biscuit has a low gluten quantity but contrary to this opinion, it is desirable that the gluten bonds show strength during the baking process. While the gluten content and weak / strong gluten ratio (index) that can be measured through the classic methods can meet the first specified request, measuring the bond quality against the heat is only possible through the rheological tests. It is possible to find at the market devices that are specifically designed for this purpose and can measure this through a sole test and at the same time, provide assistance within the scope of the quality control and R & D by making it a standard profile.

PENTOSANS The wheat endosperm contains a large number of cells consisting of starch granules in the protein matrix. Each cell is surrounded by a thin cell wall, known as the pentose, consisting of polysaccharides that include the anhydrous pentose units. Even though these substances, also called hemicelluloses and wheat flour scales consist of 2-3% of the flour, they can absorb as 10-11 times much water as their weight. According to some researchers, pentosans reduce the spreading factor of the biscuit. The pentosan quantity and functionality that remain untouched until today and are backed by quality criteria can be actually determined through a long standing method. This functionality can be measured with long solvent holding capacity of the flour. Automated systems have been devised for the measurement of the Solvent Retention Capacity, referred to as SRC and thus, this value can easily be measured in a short time.

As in the world today, there are many biscuit producers in our country and all manufacturers are working on innovations to make their products preferred by the consumer. The most important issue considered in the R & D activities are the suitability of flour for the biscuit production and how it reacts to other components and the popularity of the end product. As well as requiring the suppliers to establish the quality of the resulting flour, the biscuit producers want to test the new products before the pilot production at the laboratories. This encourages biscuit producers to deal with qualitative analytics and economically appeals the customers.