IMA Coffee, through its brand IMA Coffee Petroncini, explains how to optimise green coffee receiving and cleaning operations in order to improve the value of the end product.
According to green coffee handling and roasting manufacturer IMA Coffee Petroncini, growing costs of green coffee already cleaned and an increasing presence of impurities during its journey from harvest to the roasting factory, have led roasting companies to evaluate in-house treatment options.
IMA Coffee Petroncini Sales Director Luca Giberti says further issues concerning ethical sourcing and the quality offered by single-origin products have fuelled the demand for green coffee cleaning and sorting systems for medium and large roasting factories.
“The fewer the impurities are, the greater the worth of the end product. Companies are therefore seeing how vital it is to take control over the in-house treatment options and technologies to ensure constant raw product quality,” says Luca.
Luca says what makes a difference right from the beginning is providing the most suitable coffee reception operations, in line with each facility’s cleaning and storage requirements.
“IMA Coffee provides the best solutions to optimise all different ways of coffee receiving, from a single 60-kilogram jute bag up to bulk-loaded coffee onto a trailer or in a container, from small production to huge plant capacities,” he says.
More than 100 years of market experience has led the company to develop the broadest range of tailor-made solutions for green coffee reception. This ensures gentle and hygienic treatments are customary from the start in order to avoid any damage, product loss and/or contamination.
“For smaller plants processing 500-kilograms of green coffee per hour and receiving 60 to 70-kilogram pallet-loaded jute bags of green coffee, suitable reception equipment should be handled indoors on a hopper and cut open manually. The hopper can be installed underground or on a supporting frame, then the coffee can be transferred to storage silos or directly to the roaster using a pneumatic system,” says Luca.
He says the most convenient solution for plants with a larger capacity is bag reception from trailers, equipped with an integrated tilting unit.
“However, it is just as easy to extract the bags from the container and place them on a tilting unit inside the reception area. Combined with a sorting unit which handles the bags downstream, bags can simply be fed one by one into the cutting unit,” Luca says.
“Belt conveyors are another flexible solution to bring the bags inside the facility. The conveyor can extend telescopically into the delivery truck, allowing operators to position the bags on the swivel head, combining automatic bag opening or palletising systems.”
Luca says increased attention on in-house treatment options helps eliminate defects and impurities found in bags of green coffee, such as empty grains, half black or black beans, unripe or damaged beans, fragments of iron, wood or stones.
In-house cleaning solutions also gives roasters maximum control, especially for large companies that process tonnes of coffee a day.
“In facilities handling about three tonnes of raw coffee per hour, a complete in-house cleaning solution is an astute investment because eliminating unwanted elements present in poorly cleaned coffee, thus significantly improving the commercial value of the end product. In addition, getting the cleaning strategy right will have positive effects on the processing stages downstream.” Luca says.
“Starting with a basic cleaning sieve, which can be fitted with a magnetic surface to eliminate iron-based impurities, it is possible to separate impurities that are finer and/or coarser than the coffee. These machines are equipped with an aspiration system that is connected to a filter for dust removal and are highly recommended to plants processing up to 500-kilograms per hour, even when receiving ready-cleaned coffee. This doubles the effect of cleaning by removing foreign bodies, thereby improving coffee quality.”
IMA Coffee also provides a dry destoner to remove foreign bodies with a specific weight higher than coffee, such as stones and pieces of metal. This can be combined with a gravity table to separate foreign bodies that are almost the same size as coffee beans but with lower density items such as wood and aluminium impurities.
Luca says today the most advanced and effective cleaning technology is an optical sorter, that separates coffee by shape and colour. He usually recommends this equipment as an all-round cleaning solution, combined with a seve.
“Optical sorting machines are available with one to seven chutes to satisfy any production capacity requirement and for multiple passes,” Luca says.
“It is also a versatile solution as operators can adjust the separation parameters according to the frequency and importance of the defects to be assessed and eliminated. This means having close control over the process and consequently optimising the profits.”
“Once cleaning operations have been completed, a weighing station ascertains the weight of the rejected material. Losses in product volume are compensated for by the incremental value of the sorted product.”
IMA Coffee Petroncini strongly recommends roasters to improve the value of green beans, to avoid processing defected beans and tarnishing the final coffee taste.
“For example, a proper cleaning process can limit the presence of white beans, which are yellowish beans that are seen at the end of roasting. They are grains that come from unripe or underdeveloped coffee berries from weak branches of plants grown in poor soils. The absence of organoleptic substances in the beans does not allow any transformation or reaction during the roasting process. If present in excessive quantities, they could produce a sour taste similar to raw peanut or cardboard. The dry sensation they leave on the palate can seriously affect the quality of the cup,” Luca says.
“For these beans, roasting cannot help, as it will never be able to change the structure. The only solution to reduce or eliminate them is more accurate cleaning and the selection of green beans. That’s why some optical sorters can also sort roasted coffee, separating the lighter beans from the darker beans.”
Considering plant capacity and optimisation of handling operations, Luca says every customer can decide the preferable way to receive and treat raw coffee in their facility.
“A tailored engineering solution should combine the customer’s logistical needs and production expectations with the available space and budget, considering the necessary manual operations involved,” he says.
“It’s not always easy to find the perfect match, but what makes IMA Coffee proud every day is the satisfaction in reaching the goal together with the customer at the end of every project.”
For more information, visit www.ima.it/coffee.
This article appears in the February 2023 edition of BeanScene. Subscribe HERE.
