Coffee needs roasters like fashion needs designers. Roasting is a fundamental phase in the production of coffee and just one of the many responsibilities of roasters.

Coffee storage

Roasters import large quantities of green coffee for storage, to ensure a stable supply and demand cycle, and, with Malongo, to ensure that our Single-origin products are also available on a long-term basis for blends.

Organic green coffee is transported and stored separately from other coffees.

Si le café vert est certifié « biologique », il doit être stocké à l’écart des autres cafés.

Inspecting coffee 

Roasters start by checking the appearance of the coffee. They then check for defects. The classification of defects is referred to for 300 grams of green beans. The sample is immediately roasted in a laboratory and tasted.

Here at Malongo, we complete this process in full before accepting any new delivery of green coffee. 

Transforming coffee

Roasting green coffee means subjecting the beans to heat. The sugar and water will start to caramelise. After ten minutes, the water will have completely evaporated.  The sugar and acid will develop aromas. Three to start with. And about a thousand at the end of the process.

This complex coffee transformation is named for the chemist who analysed the phenomenon:  Maillard reactions.

Traditional roasting

Green coffee is poured into a container heated by gas burners to 220 °C. The arrival of the cold coffee rapidly reduces the temperature to 120°. The temperature increases to 220° once again in 20 minutes.
The process is controlled automatically during the first 17 minutes. A few beans are then checked visually and for odour at this point.
After 21 minutes, the coffee falls into a cooling tray. Blue carbon dioxide smoke is emitted. This gas carries aromas. The coffee is roasted. It has lost 20% of its weight. It has gained 60% in volume.

A second cooling method is possible, using water. This method is effective, but wets the roasted coffee. 5% humidity is legally acceptable. However, this method oxidizes the coffee, blocks the aromas and plays a role in the weight of the packet of coffee sold.

Quick 10-minute roasting

The green coffee is placed in a column. 60 HP turbines blow air at a temperature of 360° for 10 minutes. The coffee is roasted, but baking is stopped at the precise moment that the Maillard reactions should have started. The coffee has therefore changed colour, but has lost its acidity and gained in bitterness. Only 30% of aromas are developed.
This coffee is so hot that only water cooling  is effective, causing oxidation, blocked aromas and water adding to the weight of the packet of coffee.

90-second flash roasting

Very high temperature, and a ton of waves: the coffee is roasted…
At this temperature for 90 seconds. Maillard reactions are totally impossible. The outer surfaces of the beans are roasted, however they are still green inside. Only water cooling is effective, with all of the above drawbacks.
This is the most economical method, and the method used by the large international roasters.  It is also the method producing the worst quality coffee.

Types of roasting

  • Blond roasting This is the type used in Nordic countries. This type of roasting produces a light, acid, non-bitter coffee.
  • Medium roasting In Germany and the United States. A light, slightly less acidic and barely more bitter coffee.
  • Continental roasting, In France and northern Italy. A careful balance of acidity and bitterness.
  • Neapolitan or Spanish roasting A non-acid, but very bitter coffee.

Checking quality

The roasting laboratory monitors the quality of the green coffee before roasting and the final roasted coffee. The final aroma must be assessed. Chromatographic analyses can be used to detect the different aromatic ingredients. Humidity, particle size and colour must be checked.

Malongo has set up its laboratory within the actual roasting plant. All analyses are performed before, during and after. We planned for the phytosanitary risk of coffee rust and implemented detection systems several years before legislation made prevention mandatory.

Packaging coffee

Coffee is still alive after roasting. Packaging must guarantee quality.

  • The aromas released in roasting are immediately exhaled.To avoid this loss of aroma, Malongo immediately packages its coffees.
  • Coffee ages. Coffee beans oxidize in 20 days. 5 days are all it takes for ground coffee to oxidize. Malongo organises immediate vacuum packaging to avoid any oxidation.
  • The coffee can continue to live. With immediate vacuum packing, the coffee releases its aromas into the packet or can.
    This is why Malongo leaves a small empty space in the can or fits a freshness valve on its packets. A slightly concave can seal or packet are signs of freshness and quality.