Chorongi Factory (wetmill) is one wet mill in the “Mutheka Farmers’ Cooperative Society Society” in Nyeri in Central Kenya. Nyeri is located on the slopes of Mount Kenya and together with the neighboring region Kirinyaga it’s known for coffees with most intense, complex, and flavor-dense cup profiles world wide. It is made up of mainly smallholder farms. The farmers are organized in Cooperative Societies that acts as umbrella organizations for the Factories (wetmills), where the smallholders deliver their coffee cherries for processing.
Chorongi coffee factory is part of the Mutheka Coffee Farmer’s Society, consisting of more than 5600 active farmer members, with around 1000 of them belonging to Chorongi. Smallholder farmers delivering cherry to the factory have an average of 250 coffee trees each. Other crops grown are maize, bananas and beans. The factory is receiving assistance from our partner Coffee Management Services (CMS). The long term goal is to increase coffee production through farmer training and input access, and Good Agricultural Practice seminars are conducted year round. Our wish is to establish a transparent, trust based relationship with the smallholder farmer, helping to support a sustained industry growth in Kenya, whilst bringing premium quality to our customers, and premium prices to the farmers.
Through the pre-financing they receive, farmers are given advances for school fees and farm inputs. The factory manager is re-trained every year by CMS, in addition to field days being held by the minister of agriculture and agrochemical companies that deliver inputs to the farmers.
After picking, ripe cherry is brought to the factory before it undergoes processing to remove the skin and pulp – known as the wet processing method. Wastewater is discarded in soaking pits, and is also recirculated for conservation. The factory is using a disc pulper with three sets of discs to remove the skin and fruit from the inner parchment layer that is protecting the green coffee bean. After pulping, the coffee is fermented overnight to break down the sugars, before it is cleaned, soaked and spread out on the raised drying tables. Time on the drying tables depends on climate, ambient temperature and volumes under processing, and can take from 7 to 15 days in total.
Nyeri has a mix of smallholders and block holders with small to medium farms. The ones that don’t have their own processing equipment delivers cherries to their local Cooperative. Most coffees are grown under shade from Gravelia and Muringa Alloevella trees. Many of the farmers are surrounded by several wetmills. They are free to choose where they want to deliver their cherries as members. Due to the traditional auction system in Kenya, quality is rewarded with higher prices. The better factories will then attract more farmers by producing coffee getting the highest prices, as well as giving high payback rate to the farmers. This can in some cases be about 90% of the sales price after cost of marketing and preparation is deducted.
Varietals: The smallholders mainly have SL 28 and SL34
Grade: AA, AB and PB refers to the bean size.
Production process: Cherries are hand sorted for unripes and overripes by the farmers before they go in to production. A disc pulping machine removes the skin and pulp. The coffees are graded by density in to 3 grades by the pulper. Grade 1 and 2 go separately to fermentation. Grade 3 is considered low grade. The coffee is fermented for 16-24 hours under closed shade. After fermentation the coffees are washed and again graded by density in washing channels and are then soaked under clean water from the Gatomboya stream for 16-18 hours.
Drying: Sun dried up to 21 days on African drying beds. Coffees are covered in plastic during midday and at night.
General information: Kenya mainly produces fully washed coffees, and is considered by many as the world’s number one quality producer. There are more than 700 thousand coffee farmers (smallholders) representing about 55% of the production. The rest is mostly Estates.
FARMING AND PRODUCTION
The Cooperative Societies are the umbrella organization for one or several wetmills. Typically you have the Tekangu society that represents the wetmills Tegu, Karogoto and Ngunguru. The wet mills in Kenya are called Factories, e.g. Karogoto Factory.
A typical wet mill can have about 1000 farmers delivering cherries. They give a small advance payment at delivery. The better and well-managed wet mills are able to give more than 85% of the sales price back to the farmers. That’s after cost of milling and marketing is deducted.
Is done at the wet mills or at collection centers. When the farmers arrive at the place for delivery they would normally have to empty their bags on the floor (on a cover) to sort out unripe, overripe and CBD infected cherries.
When they start the pulper the cherries go by gravity in to the machine. They normally use disc pulpers such as old three disc Agaarde or similar brands. The parchment flows from the discs with water allowing the parchment to be separated by density. The densest beans will sink and are pumped straight through a channel to the fermentation tank as P1 (parchment 1 and is what we generally are buying.
After pulping, the coffees are dry fermented (water is drained off) in painted concrete tanks. Normally they are fermented for 18-24 hours. Many factories do intermediate washing every 6 – 8 hours, meaning they add water, stir up the parchment and drain it again.
Washing and soaking
When fermentation is completed and the mucilage is disolved the parchment gets washed in washing channels and graded again by density. The lighter beans will float off and the remaining dense parchment will normally be soaked in clean water up to 24 hours.
DRYING AND CONDITIONING
After soaking, the coffees are skin dried at hessian mesh mats for skin drying up to one day. After a day the coffees are moved to the traditional drying tables. The coffee is then normally dried on a surface of jute clothing or shade net on top of the wire mesh.
The drying time varies between 12 and 20 days depending on weather and rainfall.
Sourcing, milling and export
The dry mills in Kenya works very well and are highly professional and efficient. The coffees goes through their standard grading systems:
E (Elephant beans) = screen 19 and up, AA = 17/18, AB = 16/17, PB = Peaberries.
In the mill everything is kept separate for the auction, and it’s a great opportunity to cup through the different grades from the same outturns and consignments.
At this point we are able to do extensive cupping at the mill or the at the lab of the marketing agent to be able to pick out our coffees before they enter the auction catalogue.
Whenever we have found a coffee and want to commit, we will have the marketing agent negotiate the price directly with the producers (in our case the Cooperative Society as we normally buy from the smallholders cooperatives).
The good thing with the system in Kenya is that everything is more or less separated into small lots and different grades. If you buy coffees direct through the second window, the producers expect to get prices above the average auction prices at present time. In addition the system is transparent as everybody knows what’s going back to the society after cost of milling and marketing is deducted.
In fact many of the more serious Societies and factories are competing, getting cherries in from the same areas, and are putting effort and pride in giving the best payback to their farmers. Some of the Coops we work with have been able to pay up to 90% back to the farmers.