Today, large bakeries follow the trends of the industrial world such as improved efficiency and ability to meet customers’ needs for quality and reliability. When a certain volume per baked product item is reached it is possible to obtain additional cost savings by on-site production, as an alternative to purchase and storage of key volume ingredients like margarine, shortening and cream fillings.
Improved economy by savings on the cost of ingredients, in-house control of quality and optimised logistics are some of the advantages achieved by producing margarine and shortenings on-site or in-house.
Filling cream is a unique product group since the cream often has to be produced near the filling stations in order to exhibit optimal consistency for the application. Historically, creams are produced batch-wise resulting in varying quality, thus the production and the performance of the cream can be improved considerably by continuous production methods.
Consumers, food technologists and bakers all have different conceptions of “creams”. Among the industrial bakeries the word cream commonly describes a mixture of fat, sugar and perhaps additional components like cocoa powder and milk powder – or sometimes even water. In practice, the bakeries often do not differentiate between relatively hard fat and sugar mixtures and softer mixtures containing water. However when the processing line is designed, large differences occur in respect to choice of e.g. pumps and scraped surface heat exchangers (SSHE) from one product to another.
Creams used in bakeries can be grouped and listed as heavy creams, light filling creams with water and light filling creams. The choice of processing equipment will depend on which category the cream belongs to:
- Heavy creams – typical products: sandwich cream, biscuit cream
- Light filling creams – typical products: wafer creams, chocolate bars or biscuit fillings, nougat paste, chocolate coverings, dough improver mixed with fat
- Light filling creams with water – typical products: fresh creams, fillings for chocolate bars or biscuits
The functionality and quality of the cream depend on the application and differ accordingly, but in general bakery creams are described in relation to the following properties:
- Texture
- Sweetness
- Adhesion (in sandwich- or rolled snack cake applications)
- Firmness (to suit different climatic distribution conditions)
Heavy creams: The sandwich cookie cream falls into the heavy cream group. The process challenge of this application is the high amount of sugar (50-70% fine sugar) to be dispersed into the high melting fat mixture. The ability of the cream to set or firm up shortly after the filling onto the cookie is required, as the cream applies mechanical stability by holding together the two cookies. The crystallisation of the fat mixture is controlled in such a way that part of the crystallisation takes place immediately after the filling process.
Liquid oils and solid fat in specific ratios are melted, mixed with sugar and then quickly cooled in the SSHE. The crystallisation process is among other things dependent on temperature and time and can be controlled in the processing line, in the SSHE and in the pin rotor machine.
It is recommended to use a high pressure SSHE such as a GS Perfector or a GS Kombinator plant for the production of a heavy cream. This line can handle high pressure and high motor shaft torque applied by the product which often is firm and an abrasive suspension with poor flow properties. The line is a compact skid-mounted unit with direct connection to the filling machine in order to minimise the potential setting of the cream in the line, which can result in production halts. Typical production capacities cover 500 kg/h -1,000kg/h per skid-mounted unit.
Light filling creams: The wafer application requires slightly softer cream with the ability of holding together multiple wafer layers. The manufacturing process is similar to the one of heavy creams, as the lines should be able to handle abrasive product but under moderate pressure. Depending on the composition of the cream and the desired capacity, either one of the GS Kombinator or Perfector can be used.
Light filling creams with water: These very soft creams are typically used for rolled or filled snack cakes. The manufacturing process includes emulsion preparation, pasteurisation and crystallisation of the relatively fluid cream. For this application SSHE Consistator MD is recommended.
All of the described creams can be aerated with nitrogen or air to meet various texture requirements, for calorie reduced application or for cost saving reasons.
Gerstenberg Schröder (GS) offer and recommend the performance of pilot plant tests for cream formulations as there are no real standard solutions for the cream application due to the fact that ingredients differ from product to product and from producer to producer. The amount and fineness (granular size) of sugar and other dry ingredients, as well as the type of fats used and crystallisation behaviour, contribute to the high viscosity of the cream and hereby affect the choice of materials and design of the plant.
Process control GS Logic
The GS Logic system is designed to control, record and document important parameters concerning the complete manufacturing process. The system helps to improve plant performance by creating a consistent processing environment.
Compared to batch processes, the continuous GS process offers not only cost savings in labour and logistics but also various process and product benefits. The mixing is done efficiently, the process control is easy and can be altered to meet a wide range of cream recipes and consistencies (texture properties), the quality is consistent and uniform and the hygiene is improved.
