When we enjoy a pizza at our favorite restaurant, we don’t wonder if the bread’s consistency is as good as it could be. But the bread’s quality is a huge concern for large industrial bakeries that produce the dough for that pizza crust. Those bakeries look to their equipment makers to help them provide the best-quality dough at the lowest cost.
One of those equipment makers is SoBaTech Bakery Technology, a Netherlands-based machine manufacturer. To help customers produce higher-quality dough products, the company was looking for a dough-making solution that would allow its customers to move from batch processing to continuous. This would reduce the inconsistencies users were experiencing between the first and last product off the line.
Why use continuous instead of batch processing? Conventional machines work in much the same way people bake at home. Operators take a quantity of flour and make a well in it, add yeast, sugar, salt and water, then start mixing. The mixture then is kneaded into dough.
Traditionally, huge mixing vessels perform the kneading. The operator moves constantly from one mixer to another to add ingredients, depending on the quality of the mixture.
As a result, batch production of dough has some disadvantages. The number of mixers one person can operate is limited, which means production capacity quickly reaches its upper limit. Mixers arranged in a carousel do perhaps have greater capacity, but the quality of the dough is less consistent.
Also, differences in quality between batches are unavoidable. This phenomenon occurs because the first dough in a batch is younger than the average, while the last dough is older.
Reinventing the Process
To address these issues, SoBaTech developed the ContinoMiXX machine that produces the continuous flow of evenly kneaded dough that industrial bakeries need for making bread, pizzas and tortillas. The new machine distinguishes itself from conventional dough machines because it makes dough in one continuous process rather than multiple batches. The machine can help bakeries increase dough consistency and save up to 30% in energy usage.
When SoBaTech started developing the machine, it had to make sure that every ingredient in the mixture will be added at the right time and in the correct volumes to minimize costs and keep quality consistent. The machine’s process regulation and control allows for accurate kneading and mixing, and raw material dosing, and the company selected Rockwell Automation because of its open architecture.
Making the dough requires adding ingredients in the correct ratio by controlling the material feed rate, by weight. To achieve accurate dough mixtures, the company also integrated weighing solutions from Hardy Process Solutions, a participating Rockwell Automation Encompass Program Partner. This is achieved using Hardy’s HI 1756-2WS plug-in weigh scale modules, which are installed into an Allen-Bradley ControlLogix programmable controller rack.
The Hardy Process Solutions’ weighing card takes care of the initial filtering of the weight signal, and the programmable controller performs the flow calculation and control. The process uses a loss-in-weight (LIW) dosing principle. Raw material weight is reduced in the feed hopper, and as it reaches its low limit, the hopper is refilled from a storage container above it.
During this fill period, the system switches over temporarily from gravimetric dosing to volumetric dosing. SoBaTech developed a programmable controller LIW application with its own LIW algorithm, integrated with Hardy’s plug-in scale modules and the CompactLogix programmable controller from Rockwell Automation.
Benefits of Continuous Production
With the continuous dough machine, there’s no difference between the first and last product off the line. Every portion of dough on the line is the same age. The dough has a constant temperature, density and homogeneity (dough structure). Each of these properties is something industrial bakeries have not been able to achieve before now.
With this continuous process machine, kneading is highly efficient – producing energy savings of up to 30%. Energy is also saved because the dough needs to be cooled only briefly or not at all.
In addition to constant quality and increased efficiency, continuous dough preparation has economic benefits because the entire preparation process is fully automated. The operator simply monitors the process, easily saving four operators.
In addition, a secure Internet link with VPN allows SoBaTech to provide remote support to customers for the entire control system with access to the programmable controller, human-machine interface (HMI), dosing and drives.