Brunet

History

Brunet presents itself as a Buenos Aires firm founded in 1919. The date comes from its own site, in the form “Desde 1919.” No independent trace was found, no company deed, no trade press, no old catalog. The Internet Archive does keep copies of the site, one of them dated June 2013, but their content could not be read from this session. A 2013 copy proves only that the site existed then, not that the firm is a hundred years old. What can be verified, on the other hand, is the coherence of the range. Brunet does not sell an isolated machine, it sells a complete chain. Roaster, cooler, smoke incinerator, silo, grinder, display hopper: each station carries its reference and its named components, with their power ratings. This is the signature of a manufacturer, not of a reseller importing a brand. The second sign is local. Brunet builds two clearly separate lines of roasters, the tostadoras and the torradoras. The torradoras carry a sugar elevator. Sugar therefore enters the drum during roasting. This is café torrado, that sugar roasting practiced on both sides of the Rio de la Plata. European manufacturers do not equip for this habit. A firm that makes this machine answers first to its home market. The presentation texts, for their part, have aged without being corrected. They announce at times more than ninety-five years of activity, at times nine decades.

What it makes

Brunet builds cylindrical-drum roasters heated by hot-air circulation. The firm uses the same wording for the whole range, “con circulación de aire caliente.” Heat therefore arrives through the hot gas that passes through the charge, and not through the drum wall. This is convection, not conduction. It is not for all that a fluid bed, where the air stream would carry the bean on its own. Here the bean remains stirred by a rotating cylinder. The machines divide into horizontal and vertical ones. Control goes from manual to pneumatic, then to the programmable controller at the top of the range. Around the roaster, the firm makes the rest of the chain. The coolers are rotary-cylinder or perforated-base types, in SAE 1010 steel. A gearmotor of 2 to 5 hp drives the stirring of the bean. A second motor of 5.5 hp drives the centrifugal turbine that draws air through the layer. Then come the smoke incinerators, the silos, the grinders and the display hoppers. The incinerator carries a chaff separator with a helical duct. The chaff is the thin silvery skin that comes off the bean during roasting. The duct separates by centrifugal effect, then pushes the gases toward the burner. The afterburner chamber is made of refractory stainless steel AISI 316 and receives interchangeable catalysts. The burner of this incinerator is not built by Brunet. It is an Espargas 91-55, driven by an LGB21 or LGB22 flame programmer.

The models

The catalog of tostadoras comes in four blocks, and eight loads in all. The site names the family, then lists under that name the loads in kilos per batch. The K.H is manual, in 20, 30 and 60 kg, with a single-effect cooler. It is announced at 50, 75 and 150 kg per hour. The K.H-S is semi-automatic, with pneumatic control, in 60, 120 and 240 kg, with a double-effect cooler. It is announced at 150, 300 and 600 kg per hour. The K.V-A is vertical and automatic, in 120 and 240 kg, controlled by a PLC. It receives a cylindrical cooler and elevators for raw and roasted coffee. The torradora line has only one model, the 240 K-VT. Its name announces 240 kg, but the page offers it in 120 and 240 kg. It is vertical, under a PLC, with a rotary cylindrical cooler, smoke incinerator and sugar elevator. The coolers have their own references. For tostado coffee, the page prints M60K-HS, M2120K-HS and M240K-HS, with turbines of 2, 3 and 4 hp. For torrado coffee, M120K-ES and M240K-ES, with turbines of 5 hp. The smoke incinerators come as MQ 30K, MQ 60K, MQ 120K and MQ 240K. The industrial grinders are the MK 5, at 6 kg per minute and 5 hp, and the MK10, at 10 kg per minute and 7 hp. The Medio Punto display hopper holds 5 kg of whole-bean coffee. The coolers, the grinders and the hopper are dimensioned to the millimeter in the catalog. The roasters, for their part, receive neither dimension nor weight.

What you gain

Hot air carries the heat to the bean without passing through a burning wall. No contact surface is therefore hotter than the gas itself. The burnt flat face, the classic defect of an overloaded conduction drum, disappears in effect. The same stream that heats lifts the chaff and sends it to the helical separator. Cleaning of the bean thus sits within the heating circuit, with no separate station to install. Finally, the range follows a single throughput rule, 2.5 batches per hour from 20 to 240 kg. A shop therefore sizes its day without redoing its calculation when changing machine.

What you lose

Convection stores little heat in the metal. A cold charge therefore makes the air temperature drop at once, and recovery depends on the burner alone. The catalog does not say whether this air is recycled or discharged after a single pass. In both cases the roasting smoke must get out, and the firm acknowledges it by selling the incinerator separately. The MQ consumes 32 m³ of natural gas per hour and claims only 90% cleaning. Its catalysts are given as interchangeable, so they wear out. The catalog gives neither their service life nor their price. The grinders receive a temperature probe and a digital pyrometer with adjustable cutoff. The roasters have none in the catalog. And this single throughput of 2.5 batches per hour across the whole range looks like a nominal figure, not a measured time.