Opportunities in Baking
With more than 500 projects completed with less than one year to payback, Cargill Optimizing Services understands how to decrease costs and increase yields in the food and beverage industry.
In September 2010, COS was highlighted at the International Baking Industry Exposition in Las Vegas. Over the past 2 years, the COS team has had the opportunity to help increase efficiencies a range of fresh and frozen bakery operations. This Bulletin, therefore, will focus on some of the common issues and approaches to addressing them that have been identified.
- Asset Utilization
While there is huge variety in terms of scale, product format and product type, many baking and frozen dough manufacturing plants share similar characteristics and face similar challenges. Cargill Optimizing Services has been effective in helping both fresh and frozen bakers through the application of a range of different tools and a holistic overall approach.
One of the key challenges faced by many bakeries is accurately calculating, and then maximizing, the overall process yield – the mass of raw materials that are sold as final product. While relatively simple in concept, accurate yield calculations are complicated by a number of factors:
- Water, and often ice, are added to the dough during mixing and part of this water is then evaporated for baked products.
- Proofing of the dough converts some of the sugars and starches in the flour into CO2, which leads to a mass loss.
- Proofing often requires the recycle of some mature dough to seed fresh dough. Shaping and trimming can also lead to recycles.
- Process disturbances can lead to waste production, but often this waste is either weighed only in aggregate or not at all.
COS’s modelling tools have been very effective in developing mass and energy balances of the bakeries, accounting for proofing, baking and other unavoidable losses. This then allows an accurate target for final product mass to be understood and for the magnitude of avoidable losses at different points in the process to be estimated. The model also mitigates the complexities associated with recycle streams and incomplete measurements.
Once the loss points have been identified, some can be eliminated relatively easily while the root cause of others can be difficult to ascertain. To tackle this, COS has used statistical analysis to understand which operating factors are correlated to product loss. In facilities that make multiple products, these losses may be driven by different factors – dough temperature and proofing time in one case, perhaps, and production run length and batch size in another. Armed with this understanding of loss drivers, operating teams can eliminate waste, thus reducing raw material and utility costs, and often increasing production capacity as well.
Energy is another big cost driver in many facilities. COS has decades of experience in using process models to perform heat integration analyses – finding the most cost efficient ways to match hot streams that are cooled or wasted with areas that are heated.
COS has also been able to find opportunities to reduce electricity use through the optimization of refrigeration systems. As discussed in an earlier Bulletin, though, it is in the interaction between the process and the refrigeration system that often offers significant opportunity. In the case of a bakery, this may come in terms of precooling product upstream of a spiral freezer, or in optimizing cooling in the dough mixer.
COS has also been successful in developing Computational Fluid Dynamic (CFD) models of the air flow patterns inside spiral freezers. The knowledge thus gained can be used to investigate energy savings through understanding the impact of air temperature; product transit speed; changes in fan speed and location; modification of equipment layout to reduce ingress air. It can also provide valuable insight into the surface and internal temperatures of products moving through the freezer, highlighting potential capacity increases or mitigating quality concerns such as final core temperature.
In conclusion, COS has found that there are a wide range of opportunities in baking related industries that our tools and expertise can be very effective in tackling.
About the Author
Charles Sanderson is the Technical Director of COS, based in Minnesota, USA. He has led the development of Cargill's simulation capabilities for over ten years. He and the team have deployed the tools in projects across Europe, Asia, Africa and the Americas. Charles graduated in Chemical Engineering from Imperial College, London and received his PhD from Sydney University in Australia.
With more than 500 projects completed that have less than one year to payback, Cargill Optimizing Services understands how to decrease costs and increase yields in the food and beverage industry.