Cocoa Bean Processing Systems
KOCOTEK assists in the development, planning, construction, installation, start-up and overhaul of primary cocoa processing equipment. From individual ‘stand-alone’ machines to complete turnkey facilities that specialize in the production of cocoa liquor, powder and butter.
Hourly capacities range from small ‘pilot plant’ or ‘artisan’ size machines up to large industrial size factories.
Cleaning & Destoning
Reliable and highly efficient cleaning machines sort any foreign material from cocoa beans. Our cleaning and sorting machines are suitable for the removal of foreign material such as wood, paper, sand and stones from not only cocoa beans but also hazelnuts and almonds.
The Lehmann cleaning machines in conjunction with the destoner are designed to be incorporated into a continuous production process and are installed prior to the winnowing or roasting step. The destoners range in capacity from 1 up to 6 t/h or can be upgraded to an optional capacity as high as 30 metric tons an hour. In addition, our cleaning equipment and destoners can be complemented with a magnetic separator or optional metal detection system for the removal of screws, nuts and other steel particles to guarantee a high degree of safety.
Lehmann Cocoa Bean Cleaning & Destoning System
The Lehmann cocoa bean multi-step cleaning system from the Royal Duyvis Wiener group is suitable for cocoa beans, hazelnuts, peanuts, almonds, coffee and various other products. The system is complete with a double vibrating screen to separate over- and under-sized product. It also includes an aspirator to remove dust and other light material such as strings and leaves.
The cocoa beans are then moved through a destoner to remove stones that are similar in size to the beans or nuts. Other foreign materials such as wood, paper, strings and sand will also be removed. The Lehmann CR Cocoa Bean Destoner can be fitted with an optional magnetic separator or metal detector for the removal of metal parts that might have found their way into the product.
Separation of foreign materials of all sizes, such as wood, paper, stones and dust
Vibrating Screen for separation of dust and tiny pieces
Removal or Detection of metal parts
Cleaned Cocoa Beans improve product quality and optimize production
Prevents damage or excessive wear to downstream equipment
Strings are removed, which clog duct work and valves, especially around the winnower
Cocoa beans have a shell, which need to be removed. The inside the shell is known as ‘nib’ and is considered the valuable part. To get the shell as loose as possible around the nob there is a ‘pre-treatment’ step. In our systems we use gentle warm air in a counter current flow.
Lehmann Shell-Pop Pre-Roasting System: Type KR
Our continuous roasters are adjustable to process any kind of bean type and origin. The systems are also designed for 24/7 production and require very little maintenance.
Continuous Bean Roasting
The Lehmann “shell-pop” pre-roaster from the Royal Duyvis Wiener group is uniquely suited to pre-treat whole cocoa beans so that optimum yields are achieved during the winnowing process.
In our gentle, yet efficient continuous cocoa bean roasting system, the shell protects the nib from being over-roasted, ensuring that all flavor components are retained in the nib. The beans pass through the roaster by gravity and are captured in layers. In each cycle, one small batch gently tumbles to the next level below. The roasting air passes through each layer from the bottom of the system to the top. Every bean receives the same amount of hot air, allowing every bean to be roasted equally and very gently.
Due to the unique ‘counter flow’ principle the beans are very gently and evenly heated, preventing fat migration and ‘sweating’ of the bean. This unique gentle process causes moisture to evaporate from the inside of the bean resulting in a ‘popped’ shell that is loose from the nib inside. This allows the breakers on the winnower to run at slow speeds because the loose shell is very easy to remove from the still ‘rubbery’ nib. In turn this leads to excellent nib-in-shell and shell-in-nib figures.
Very gentle 'counter flow' heating process
Cocoa beans are very gently mixed throughout the system
Choice of heat source: steam, gas or oil
No 'open flame', combustion air in contact with the product
Continuous gentle exhaust suitable for 'bio-bed'
Shells 'pop' away from the nib resulting in as much as 20 - 25% volume increase in the beans
Cocoa beans will have optimum temperature and even temperature for optimum winnowing results
Very gentle treatment, no need for spark arrestor or fire suppression systems
Lehmann Winnowing System: Type DBF
KOCOTEK offers the Lehmann ‘DBF’ Winnower with unique cocoa bean breaking and winnowing technology from the Royal Duyvis Wiener group. Lehmann’s sophisticated winnowing systems use multiple breaking and sieving stages to gently crack the cocoa beans and leave the nib pieces as large as possible. Capacities range from 1 up to 8 metric tons an hour. The systems are designed to process cold, roasted or pre-treated beans.
The frequency controlled rotation speed of the breakers increases from one stage to the next, with broken beans sorted between each breaking stage. Because of the multi stage breaking and sieving technology each cocoa bean receives just enough energy necessary to break the shell resulting in excellent shell-in-nib and nib-in-shell figures.
All sizes of nib and shell run through vertical winnowing ducts where the PLC controlled airflow rates take the lightweight shell up, and the heavier nibs fall onto the transport system below.
Multiple Breaking & Sieving Stages
PLC controlled air flow control in each nib and shell separation duct
Cocoa nib sample port in each separation channel
Automatic foreign material removal (no run around for foreign materials that needs to be cleaned out frequently!).
Control over shell in nib and nib in shell figures to ensure optimum yields
Large and even sized nibs - optimum for subsequent alkalization or roasting steps
Processes Cold, Roasted, or Pre-treated cocoa beans
Control over shell removal to prevent excessive wear and tear on subsequent gridning and refining steps.
Alkalization, also known as ‘Dutching’ is an optional process step that is (generally) only used when producing cocoa powders. Alkalization is a process designed to manipulate the pH of the cocoa nib prior to roasting. Alkalization changes the acidity of the cocoa solids, resulting in a somewhat milder cocoa flavor but allows for varying cocoa powder colors (from black to deep brown and even red). Over the past 30 years we have optimized our nib alkalization know-how and technology which resulted in a superior system with ultimate control over the product color and flavor.
Lehmann Cocoa Nib Alkalization Reactor: Type BNA
Nib Alkalization (or “Dutching”) takes place before roasting. The Lehmann BNA alkalization reactor from the Royal Duyvis Wiener group treats nibs with a moisture content as high as 35%. PH values of more than 8 can be achieved and high pressure and absolute vacuum can be applied during the alkalization process. This, combined with the superior internal mixing technology, ensures perfect and controlled color and flavor development. After the alkalization step, the nibs need to be roasted. Depending on the recipe the alkalized nibs need to be processed in our continuous roaster type ‘KR’ or batch drum roaster type ‘BR’.
Fully Jacketed system able to handle high pressure as well as absolute vacuum depending on the recipe
Ingenious mixing system, able to start-stop under full product load
Ability to inject additives to facilitate alkalization reaction, including steam, water, air and other additions
Large inlet and outlet for efficient charging and discharging
Short and stable mixing shaft
Optional vacuum system can be added
All nibs are treated equal for homogeneous production
PH values of more than 8 can be achieved and high pressure can be applied
Capable of handling nibs with up to 35% moisture
Optimum system for color development in the powder (yellow, brown, red and black)
Sanitary design inlet and outlet valves for optimum product safety
Lehmann Batch Nib Roaster: Type BNR
Nib Drum Roaster and Cooler
Nib Drum Roaster and Cooler
Nib Drum Roaster
The Lehman BNR Batch nib roaster consists of a gently rotating vertical drum. The product inside the drum is gently heated through radiant and convection heating. The entire process is PLC controlled so that specially designed roasting curves can be consistently repeated. Additives can be injected into the drum during the roast, even some mild alkalization steps can be executed at the beginning of the roasting process. A nib sterilization step is part of the roasting process. The integrated cooler has a ‘live’ bottom so that the entire batch is cooled efficiently to keep control over the roast.
Large diameter stainless steel drum
Ability for both convection and radiant heating
Ability to inject fresh air and hot air into the drum
No combustion air comes in contact with the product
Optimized roasting air distribution over the entire length of the drum
Reliable & high capacity
Patented combustion air to roast air heat exchanger
Maintenance friendly including easy access air handling fans
Low Nox burner
Our continuous roasters are used for drying or roasting of cocoa beans and alkalized nibs. Our roasters are also well suited for processing peanuts, tree nuts, and all kinds of seeds such as pumpkin, sunflower and sesame. The unique ‘counter flow’ roasting technique ensures that the heating curve is very gentle and even and that the product is gently mixed throughout the roasting process.
Continuous Roaster – Type ‘KR’
Continuous Nib Roasting
The advantages of the Lehmann continuous nib roasting principle have proven its value to the cocoa and chocolate industries for many years. It is an excellent roasting method due to low energy consumption, flexible flavor development and excellent color development of the end-product.
In the continuous nib roasting system, the pre-dried (and sometimes also alkalized) nibs are fed to the roaster. Small batches of nibs are all treated equally due to the gentle turning of the layers. The result: a very uniform flavor development.
Even high acid and non-fermented beans can be upgraded to a less acidic and more cocoa flavored product. Due to a low roasting temperature the exhaust air has a low concentration of odor. The nib roaster has a cooling section to bring the nibs down to the ideal temperature for liquor grinding.
Counter flow roasting process with very gentle heating (no heat stress!)
Very gentle mixing through the roast process ensuring an even roast
No 'over roast' ensuring for optimum control over flavor development
Possible to add alkalizer
Very energy efficient
Extremely low operational and maintenance costs
Space efficient, small foot print
No combustion air in contact with the product
No re-circulation of the roasting air
Cocoa Beans are sterilized to adhere to very strict food safety requirements. Sterilization also optimizes winnowing results.
Lehmann Sterilizer – Type ‘KS’
The Lehmann Sterilizer type KS generates superior germ reduction, providing consistent total plate counts below 500 cfu per gram. The prevention of moisture absorption ensures that all flavor components remain within the beans.
The hot cocoa beans are transferred from the roaster directly to the cocoa bean sterilizer; making the sterilization process more energy efficient, and significantly reduces the risk of cross contamination.
During the sterilization process the cocoa beans also ‘puff up’. This means that the shells are also easy to remove from the nib, aiding the process of breaking and winnowing and generally improving yield numbers. Compared to other systems, sterilizing hot beans saves a significant amount of energy and retains the original flavor profile of the bean.