• QA 008
    What processes are used to obtain Washed Brazils and Pulped Naturals ?
    There have been reports that consideration is being given to the inclusion of Washed Brazils as a tenderable origin on the New York futures market. What process is used to obtain Washed Brazils and the 'Pulped Natural' coffees we also hear about?
    Asked by:
    An exporter in Ethiopia

    The Brazilian washed process or wet process is fundamentally the same as elsewhere.   Go to 11.01.02 for a visual description of the wet process generally (Link below).

    Washed arabica is however a relatively new segment of the Brazilian coffee industry that has only come to the foreground in recent years.   But this 'late arrival' has enabled Brazil to benefit from developments and innovation elsewhere, for example in the limitation of water use, the disposal of effluents and so on. Fermentation is usually done under water, rather than 'dry', but a number of producers also rely on mechanical mucilage removal. These mostly use compact units that minimize water usage - the so-named ecological or eco-pulper.

    Pulped Naturals: The pulped natural process consists of flotation (remove floaters, dried cherry etc), followed by pulping by means of a screen pulper that simultaneously pulps ripe cherry, and separates out the unripes.  The pulp is then separated from the parchment using a modified drum pulper that simultaneously pulps any small ripe cherry that may remain. The main difference with the wet process from here on is that the parchment is not fermented or washed, but instead it is immediately dried with the mucilage adhering to it. The process was introduced in the 1990's in order to eliminate the mixture of unripe and ripe cherries found in the dry process as a result of mechanical harvesting. This problem persists even after flotation because flotation as such unfortunately does not deal with unripe cherry.

    Initial or pre-drying takes place immediately after pulping. This is done on concrete floors (patios) in the open sun with the parchment spread very thinly, maximum 2.5 cm thick and very regularly turned, for example every half hour or so.

    Once the parchment no longer sticks to one's hand it is ready for conventional sun drying or mechanical drying as the case may be.  When weather conditions are not conducive to pre-drying the grower may use a mechanical mucilage remover instead to partially remove the mucilage to facilitate the pre-drying process.

    Some of the immediately obvious advantages are: 

    • the total quantity to be dried is much smaller than in the traditional dry process; 
    • green and substandard cherries are removed thereby improving cup quality; 
    • and the cup quality generally becomes more table and even throughout.

    At the same time there is also a growing perception and appreciation in the market that some of these Pulped Naturals can offer interesting flavor profiles and are creating a niche of their own.
    By end 2004 the estimated production of Washed Brazils was expected to reach 500,000 bags plus,and that of Pulped Naturals between 2.5 and 3.0 million bags.  Especially production of Pulped Naturals is expected to grow quite sharply but there are substantial barriers to convert from producing pulped natural to the washed process. Not only is the cost of wet processing equipment, civil works and effluent treatment high, but major changes in dry processing, storage techniques and marketing channels are required as well. 
    For a complete review of coffee quality and processing (arabica and robusta) go to 11, Coffee quality (Link below).
    For more on Brazilian coffee go to www.cecafe.com.br,  the website of the Brazilian Coffee Exporters' Federation , and www.bsca.com.br - the Brazilian Specialty Coffee Association (both in Portuguese only). For an introduction to Brazilian processing machinery visit www.pinhalense.com.br .

    Posted 21 December 2004

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