Due to the increasing consumption and pursuance of convenient products, snack food has growing influence in the market. Biscuits are one of the most popular product of snacks and there are new varieties of biscuits keep coming out every now and then.

In the recent market, we have collected a number of popular biscuit products to give a categorization and brief introduction of their production technology. It will help the customers who are new to the biscuit industry to immediately recognize the equipment that they need for specific product.

To categorize the biscuits, first need to understand the main categories of it. For biscuits, there are 4 main types: crackers, hard biscuits, soft biscuit and cookies. For these four types of biscuits, there will be a brief introduction below for their features on the shapes, surface appearance and texture. Their production technologies are also different.

Characterization

Cracker

Featured products:

Open and crispy texture, light and multiple layers structure, even pinholes and blisters on the surface, contrast color between dark blisters and pale background colour. Usually with salty flavor, low moisture content, oil spray and seasoning topping. The soda cracker is baked in complete sheet or stripes. Need fermentation

Hard biscuit

Featured products:

Even colour and clear smooth surface, hard and crispy texture. Low moisture content. The dough has low sugar and fat, with strong gluten and elasticity.

Soft biscuit

Featured products:

Higher fat and sugar content than cracker and hard biscuit, soft and crunchy texture. The dough of soft biscuit is usually in loose status, no need to be pressed to sheet, directly moulded by the printing roll. The surface usually with protruding characters or pattern, but for few specific product like digestive biscuit, it has even pinholes and the pattern is sunken on the surface.

Cookie

Featured products:

High fat and sugar content, with inclusions of chocolate chips or with center filling of jams. The dough of cookie is soft and loose dough, or even semi-liquid. They are formed by depositing and extrusion.

Technology

For the main four categories of biscuit, they apply different technology and hence different equipment. The use of their ingredient also decide the way of its mixing.

Cracker

The dough of cracker is usually flour with strong gluten to ensure the open cracker texture. It is leavened and fermented with ingredients such as yeast, ammonia and sodium bicarbonate. It requires two stages mixing and repeated fermentation after eveytime’s mixing. It is usually better to be mixed by vertical mixer with two or three vertical spiral arms. The vertical mixer will automatically lift up the dough tub with a fork and knead the dough evenly from the top to the bottom. It does not require the dough to be poured out for mixing, which is easy for the second fermentation.

The cracker product requires expansion at the beginning of the baking to form its structure and in the latter stages to extract moisture from the dough pieces. It is usually baked with direct fired oven.

Hard biscuit

The cracker and hard biscuit share very similar production process, both require cutter to cut the big mass into smaller pieces, then go through several stages of pressing by the gauge rolls to become a thin layer of sheet. The major difference is the cracker requires laminator to form the multiple thin layers inside the final product. The hard biscuit dough is less strong than the cracker dough, it can be mixed and kneaded by the horizontal dough mixer.

Soft biscuit

Soft biscuit and cookies share completely different mixing and forming process with hard biscuit and cracker. Both require only one forming machine. Soft biscuit is made of weak gluten flour, it is in loose status after mixed by the horizontal mixer. It does not require multiple stages of pressing like hard dough, the loose dough will be kibbled into more small particles by the kibbler and formed by the embossing roller inside the rotary moulder. Its shape is decided by the selection of the mould. After moulding, the individual piece of biscuit can be directly sent to the baking oven for baking. Unlike hard biscuit and cracker, the soft biscuit has lower requirement for the baking as it does not require the changes of the heating at the former stage and latter stage of baking.

Cookies

To produce cookies, there are three forming machine for different types of cookies. Cookies have three main categories: wire-cutting, depositing and encrusting. These three categories require different dough and so result in different method of forming. Below table will brief introduce the difference between the cookies and their technologies.

Like soft biscuit, the baking of cookies requires more mild temperature and cannot be directly heated with the fire. Unlike crackers, it does not require expansion and areas with darker color. It requires even color on the surface. Therefore, in the production line of cookies, it usually configured with Direct forced convection or Indirect forced convection oven which bake the biscuit with forced air that is heated inside the burning chamber. The burning chamber is separated from the baking chamber and the flames will have no contact with the products.

This article is for understanding the difference between different types of biscuits and the basic requirement of their production. Potato chips does not belong to the categories of biscuits, but it can share the same technology and equipment of the biscuits. It will be elaborately explained in the next article.