Setting up a bakery - Equipment Selection
This series covers various topics around setting up a bakery, and in particular an industrial size factory making bakery products.
How to start a bakery business?
The first article covered the basics around choosing products, markets, standards and making a fail-safe business plan. It might be wise to stress the following: part of making a business plan is doing your maths homework on your costing will be/ can be.
The second article focuses on defining your type of product, with essential parameters for shelf life, factory design and consequences from that.
In the third and final article we will focus on equipment choices by leading you through two popular products.
Brands, innovative design or proven concepts?
When deciding on equipment price for the equipment is only part of your investment. Cost of Ownership is much more important for most customers. Longevity and availability of parts, robustness of frames and software are sometimes not considered when buying, but play a vital role in the day-to-day operation. Another thing to consider might be the fact that the production line or machine(s) have been delivered and working properly already to several other manufacturers for the same intended use.
On the long run your company only can and will continue existing when it has a minimum on unscheduled downtime, maintenance cost, fast product changeovers and a minimum of waste/ scrab production.
First decision: Products
In the previous two articles we discussed a large amount of information you need to collect and decide upon before starting. Perhaps it is worthwhile to mention that every choice often implies a whole range of new questions, some easy some not. As we currently are looking to decide upon equipment we need to choose for a set of products to work from. We will however not consider the ingredients being used, as your can write an article on that for each product.
We will consider in the article hereafter two very popular products: Oreo from Mondelez and Caramel Biscuit/Speculoos from Lotus Bakeries.
The products are quite dry and can be considered in the category: Low Aw, low moisture and long shelf life (as discussed in previous article). Furthermore they share the fact that they are rotary moulded and considered a short dough biscuit. The Oreo has a secondary processing step called sandwiching.
Second decision: Operating capacity
The time that you want to produce, is partly philosophy, beliefs combined with a large dose of common sense and economics. Secondly, you need to consider that experience learns that when embracing new technology for you and your company you will need at least 1 year to master it and thus before coming profitable.
Depending on country’s legislation, unions, religion, etc. one can decide for working anywhere between 5 and 7 days a week and an operating time up to 24 hours a day. The best organised medium sized business we witnessed operated 5-6 days a week between 16 and 24 hours, where in general a small night shift was present for cleaning and starting up again the production lines. We know from our own business we had that working 7×24 sometimes cannot be profitable at all: 5×24 made an enormous profit and in the last 2×24 hours we had to produce we lost all the week’s profit due to high fail costs and higher pay of the production team. So make sure that somewhere in your plans you will account for this.
Third decision: Mixing
Both products are so-called short doughs, that means they should have a low gluten development.
The low gluten development is due to a relatively high fat and low water content. Often the sugar content is too high to let the crystals be completely dissolved in the available water of the formulation. The way and amount sugar crystals are allowed to dissolve have a crucial effect on texture and shape of the biscuits. Therefore some choose for resting times of at least 24 hours in certain short dough products.
Due to the "fight" for water the flour will not be completely hydrated and thus will the dough have a varying viscosity, especially throughout the first 30 minutes.
The mixing can be done in general in batch or continues mixers, were each have their pros and cons to them. Due to the fact that setting up a bakery often means one doesn’t want a complex and costly start, we will discard continues mixers here. Batch mixers can be bought vertical and horizontal, where by far the most start with a vertical batch mixer with a set of bowls; in our business case we will look at the vertical batch mixer. This has the preference due to a lower intensity of mixing, therefore minimising the risk of overmixing by accident of these short doughs.
The size of the mixing bowl depends on the parameters that need to be set, leading from capacity (kg/hr), the number of mixing bowls, standing/ resting time and mixing programme. In general our two products are made in 2 stages, the first ("creaming") mixes longer than the second stage combined with a resting time of 30 minutes or longer. This however will depend on the composition of our dough, the specifications of the ingredients used and the amount of return dough/scrab used in the formulation; most important is that it is consistent every hour of every day in every week, as this will give the most consistent product.
Fourth decision: Forming
In general are there two ways to form the dough pieces: sheet and cut or mould. Moulding means little to no return dough and no variations in dough properties due to return dough. Another advantage can be that when decided for moulding a rotary mould doesn’t take up a lot of space. Furthermore the shape of the mould allows certain shapes and forms/imprints more easy. However when working with very small mould or very thick dough pieces, rotary moulding can be a challenge.
Due to the shape and imprint of the Caramel biscuit and Oreo biscuit we will choose a rotary moulding machine, as most original and imitating manufacturers currently do. They way the dough is divided in the hopper and at what speed it is fed to the hopper we will also choose a buffer system which will feed the hopper of the machine. This is to overcome numerous problems leading to waste in a continuing production.
Next to decide is the width you will be working at, often starting from 300 mm to 1800 mm. You will need to consider the following: the wider the moulding roll, the weight will increase and cannot be manually lifted/ exchanged. Secondly you will need to adapt your oven to the working width or vice versa. It is often a matter of product cost price, required capacity and the number of changeovers to be made. Thirdly the rotary mould should be able to keep up with the baking time, very long ovens with short baking times require high output expressed in meters per second. We have seen working up to 14 m/s.
Fifth decision: Baking
To get the most consistent end product during days and weeks we will consider a tunnel oven with a continues oven belt or baking band. From the rotary moulder dough pieces will be handed onto the belt and be baked anywhere between 2.5 to 20 minutes on average, depending on size and weight.
Baking can be done in generally speaking two ways: directly or indirectly. Depending on the length of an oven and the amount of requested intervention options, ovens are divided in compartments, at least two. We see more hybrid choices nowadays, where both are combined in one oven, however we question this for very short baking times. In general it doesn’t matter which type you choose as it is often a matter of opinion of the developer, the supplier and consultant you choose. Generally speaking we see more hybrid oven, where at least the last section of the oven is built indirectly with the objective for a more even browning and moisture loss of the products.
The observer might have noticed that we discard the electricity based ovens, we see that these are not as energy efficient as the other ovens and often much more product variations give in the means of colour and dryness and therefore play less a role in more industrialised environment.
The choice of the width of the oven belt is made in accordance with the width of the rotary moulding machine. Therefore our next choice to make is at which length the oven in combination with the baking times is required and the way you want to divide the heat during baking (top/ bottom) and extract moisture. Another contributor to the magazine biscuitpeople.com, Mr. Ian Davidson from Baker Pacific has written extensively on the topic of baking and oven designs, we therefore will not continue covering this topic here.
The baking time of the products in our business cases vary between 12 and 20 minutes, we therefore prefer 4 sections of 2 directly gas fired and 2 indirectly heated sections. Both products can be perfectly made on a (semi-)closed steel belt. When the seller of the oven is able to programme an automated moisture content in each section, you can perfectly control your products end quality; we’ve seen this once operating perfectly.
Sixth decision: Cooling
Depending on your product characteristics, the way of cooling is to be decided upon. This can be done by lengthy conveyors or spiral cooling towers with all varying design of the belt (closed or varying mesh). The length of the belts can vary from 0,5 to 7 times the baking time. Depending on how the further processing will be, after cooling they can be stacked or fed to a machine for secondary processing.
It is advisable to make that there is a very gentle and gradual cooling, to let the heat and the remaining moisture move away from the product. If chosen to work with an open belt, you should make at least one turn/ flip to let excess heat and moisture from the bottom the evaporate as well. In general no forced convection is applicable for these products and for certain products this should be avoided, to prevent checking, breaking and curving too happen.
Seventh decision: Secondary processing
Toward secondary processing one can consider sandwiching (or cookie capping), applying a coating, chocolate or jam/ jelly or even a combination of these processes. Here the most important part will be that the product or formulation used is in balance with the biscuit, therefore maintaining texture and preventing an excess dosage leading to high costs.
For the production of the Oreo we will need a sandwiching machine: placing cream between two individual biscuits and if we would like to make the complete Oreo assortment we would also need to consider applying coating and chocolate. This will make it however very costly to start up, especially as the caramel biscuit doesn’t need any secondary processing.
When choosing for secondary processing one needs to realise that for using real chocolate you need tempering machine (making sure the chocolate crystallises and shines) and a cooling conveyor. When making cream, jelly or other coatings it might be that there is a need for various vessels and mixers. For the Oreo we will work with a large mixing vessel and a hopper feeding the creaming and sandwiching stage. Depending on the ingredients chosen one can also choose to work with a continues aerator, regulating specific weight and temperature of the cream.
Eight decision: Packaging
Very important in this decision part is your current climate. All bakery products have a relative humidity, called Aw. In general Moisture does transfer from a high humidity to a lower humidity until there is a balance between the product and its environment. Based on this knowledge you can decide upon it will be a tin, tray or film/foil in which your products will be packed.
To maintain the texture you will need to control the water vapour transmission in packaged product during storage. To prevent certain oxidation (especially when working with certain fats, seeds, nuts and fruits) one needs to control the oxygen vapour transmission of the packaged product. This combined with the speed on which the film will run, will specify the requirement for the film and its sealing temperatures.
Another thing to consider will be the pack size and if it will consist of one or more products and if it will need to be a multi pack (multiple single wrapped products in a wrap).
For the Caramel biscuit and Oreo we consider single- and duo-wrapped, "large" and multi-packs. This implies in this business case we need a set of conveyors, bypasses and buffers and 2 flow wrappers. Depending on amount of biscuits running from the line we need to decide on type and make of the flow wrappers.
Although we have covered quite extensively in the past three articles a lot from the aspects of setting up a bakery we haven’t covered a lot of other things, such as setting up a quality management system like HACCP, BRC, IFS, ISO, etc. We have tried to give you pointers and ideas to think and rethink when considering starting and setting up a bakery. The key to success is to be prepared and think of almost every aspect of your business. As a group of consultants we are more than happy to help you clarify your needs, goals and according budgets. We try to do every 2 years a larger project, where we help set up a bakery from start to finish: planning, (product) development, training and commissioning; where in general these trajectories take 1 to 1,5 years throughput time.
February 2015
