Mr Roger Cook, technical and business development of the PETKUS Group
Mr Roger Cook, Senior Technology Specialist


Roger Cook is responsible for the technical and business development of the PETKUS Group activities in Australia and SE Asia. He is also responsible for the company’s optical sorting applications worldwide. Roger has been active in the designing and implementation grain processing systems for more than 15 years. In that time he has successfully completed many projects in Europe, Africa, the Middle East, Asia, Australia and New Zealand. Roger likes to work in the area of implementing new technologies and new systems for the benefit of his customers and the progression of their businesses.

Tell us something about your company, when the PETKUS Technologie GmbH was founded and what was the idea behind its establishment?

PETKUS Technologie GmbH
PETKUS Technologie GmbH

In 1852, Christian Friedrich Röber began developing seed processing technology in Thuringia, Germany. The name PETKUS was adopted in 1862, when Röber constructed the first seed cleaning machine for Ferdinand von Lochow III of Petkus manor in Brandenburg, for the especially resilient rye that grew there.

Subsequently, Röber and his sons submitted countless patents worldwide, many of which represent the key technologies of PETKUS to this day. Then the dynamic growth started. To name but one example: In 1894, sales to Russia began, with hundreds of thousands of machines delivered to the regions of the current CIS states over the following decades.

In 1994, directors Mark Scholze and Luca Celeghini decided to carry on the tradition of the international company’s prosperous formative decades. With great success, they have continued producing robust machines that are known for their excellent sorting results at a fair price. Where success in the past hung upon individual machines, the philosophy today is to design and build complete technology concepts and turnkey plants: From receiving the grain, to pre-cleaning, drying, fine cleaning and sorting, to treating, packaging and storage – every step is an integral part of the overall concept.

To further this product diversity, the existing PETKUS knowledge base was significantly expanded. Mark Scholze and Luca Celeghini have since focussed specifically on innovation, making it the company’s core activity. In 2011, they founded the ROEBER Institute, an Innovation Centre where an interdisciplinary team of engineers researches and develops new technologies for the benefit of customers of their “Made in Germany” products.

Please tell us about your latest machine OptoSelector OS 900 and how it is different from other machines available in the market.

Optoselector OS 900
Optoselector OS 900

Roeber’s new OptoSelector uses an intuitive system called ‘TeachNSort’ to self-learn the full RGB colour range of the good material. When setting the machine for the first time, the operator simply feeds in a small sample of good grain. Within a second or two, the colour profile is automatically generated. Material that does not match this good colour profile is rejected.

Those familiar with optical sorting will realize the key point of difference here. Conventional sorting relies on setting the parameters of the material to be rejected. OptoSelector recognizes the good material and rejects the rest. A practical example of the benefits of this would be comparing what happens when a monochromatic machine set to remove dark black and brown defects encounters a piece of orange plastic. It would be unlikely for the plastic to be recognized and therefore it would not be rejected. OptoSelector’s software knows that the orange plastic is not good grain and will reject it also.

Next appears another sophisticated feature of the OptoSelector. Each individual grain is recognized, whether it is good or bad, allowing a complete geometric analysis to be made. The parameters of area, length, width, stretch, compactness and symmetry can be checked and values for acceptance or rejection of the material configured.

The recognition of each grain, allows accurate data acquisition and statistical reporting of both good grain and contamination levels. The cumulative area measurements can be used to make an accurate assessment of flow rates and capacities.

As we can see that OptoSelector OS 900 design is totally different from traditional Optical Sorter Machines available round the globe, why do you think there is a need for change in the design of Optical Sorter machines? How it will benefit the grain millers?

Almost all the units sold for standard rice sorting are monochromatic that is depending on the manufacturer, an optical system consisting of coloured lamps and/or lens filters. These colours, normally blue for rice sorting, serve the purpose of ‘hiding’ the colour of the good grain from the machine’s sensor and enhancing the signal that is coming from darker material passing through the machine. Monochromatic sorting is therefore also well described as a ‘contrast’ or ‘black and white’ sort, since the machine has no understanding of the actual colour of the material. The sorting processor only sees an electrical signal coming from the sensor, it has no idea what colour that signal actually represents.

The future of ‘optical sorting’ lies in the development of machines with real full colour imaging. The OptoSelector is able to capture red, green and blue (RGB) colours as combined photographic type images. This higher level technology is able to ‘see’ as the human eye and recognize 16 million individual colours. Full colour RGB sorting is much better at detecting slight colour and shade differences in the rice. Further the geometric recognition system can better remove foreign grains and even brokens.

It also important to note here that some manufacturers are referring to their machines as ‘full colour’ when actually they are tri-chromatic. This means three individual wavelengths, without having a relationship between the three signals. These machines cannot detect the shade differences that real RGB sorting can achieve. Millers should be careful not to confuse the marketing words ‘tri-chromatic RGB’ with ‘real full colour RGB imaging’.

How OptoSelector OS 900 will benefit the grain industry round the globe?

The most benefit will be seen by high quality export rice producers and especially producers of rice paddy seed. Higher purity levels are achieved and previously indistinguishable defects can now be removed. For example, the OptoSelector is very capable of removing red rice from paddy seed by using the combined RGB colour and geometric sorting to increase its purity. Normal monochromatic sorters are not capable of making this separation.

Please brief us about the prices of OptoSelector OS 900 charged from the target users.

The price of the OptoSelector OS900 is competitive in comparison to its specification and performance level in the marketplace.

What are the different models and how are they different from the others available in the market.

The OptoSelector is offered in the OS900 size machine currently. This size machine satisfies the capacity requirements of most major mill and seed applications. It has a sorting width of 900mm and various options for configuring part of the sorting width for re-sort.

What is the future of Optical Sorter in the Food Grain Industry round the globe?

Consumers demand safe and healthy products. Seed growers and merchants should only be offering the purest grains. The technology of the OptoSelector allows these demands to be realised in a way not previously achievable. Since launch in November 2013, OptoSelector is attracting interest from many different market types and territories.

What is the importance of innovation and quality in PETKUS Technologie GmbH?

PETKUS is a company motivated by innovation and founded the ROEBER Institute in 2011 to drive the company’s new and high-tech products. Clients are assured by the ‘Made in Germany’ quality.

Can you please share with us the Market Presence of your company? Also what do have to say about competition in the Optical Sorter Industry globally?

PETKUS operate 14 of their own offices and service centres around the world, with many more local agents and distributers too. PETKUS machines are known for their exceptional quality and performance at a fair price.

Apart from Optical Sorter, are you associated with any other machinery which is used in Grain milling, If Yes please explains about that?

The PETKUS machinery portfolio is huge. Rice millers would be especially interested in our intake and materials handling systems, silos, dryers, large cleaners, plansifters and indented cylinders. PETKUS and our sister company MMW, also offer complete turnkey flour mills, feed mills, silo/machine house building structures and of course seed cleaning lines.

What are the future strategies of PETKUS Technologie GmbH in terms of Technical updates and Marketing Strategies?

The OptoSelector OS900 is our first entry in to the optical sorting market and we have entered at the highest technical level, turning many heads in an otherwise quite established industry. OptoSelector certainly isn’t where we stop; it’s just the beginning of what will become a family of leading optical sorting equipment. So as they say, “Watch this space!”

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