By Vince Fedele
For those IN SEARCH OF THE ULTIMATE CUP™
When you brew your favorite coffee and are looking forward to that perfect cup first thing in the morning, and really need for it to be that special, only-at-home perfection, your brewer is a crucial component, and must do its job perfectly, every time.
This is a quick start brewing guide for one of the best and easiest to use brewers available. The Technivorm is made in Holland, and is very well designed and manufactured to extremely high standards using high quality European components. It is one of the only drip brewers to be certified by the Specialty Coffee Association of America according to a news pointer on their web site.
After the growing, processing, shipping, storage, roasting and all of the related variables, we all know the four key variables in brewing that can produce a poor result:
a) Grind size
b) Amount of ground coffee used
c) Water Temperature and
d) Dwell time during brew
The Technivorm removes the last two variables by keeping the water temperature and dwell time during brew to that needed to produce THE ULTIMATE CUP.
This guide assumes you have identified and are loyal to your favorite roaster and coffee, and have both a proper grinder and coarseness of grind. For more info on these topics, stay tuned….
Water Temperature – how do they do it?
The KB-741, and similar Technivorm models, manages to keep the brew mixture at 198-204 Degrees F (92-96 Deg C), the best range of temperatures for drip brewing. This is easier said, than done, and the Technivorm does it by devoting the greatest expense in the product to the quality of the heater. It is an instantaneous, indirect heater, capable of processing a full 10-cup beaker in 6.5 minutes flat. This is not your father’s drip brewer….the heater is a high quality, German made, VDE tested and certified calrod heater of some 24-inches in length, brazed with precision along six spiral turns around a 100-ml metal cylinder. There is never danger of corrosion in your heated water because the tubular heating element has no direct contact with the medium to be heated. The tubular heating element consists of a metal jacket surrounding a live heating conductor made of wound NiCr wire. The conductor is embedded in high-grade, tightly compressed magnesium oxide powder, which provides highly effective thermal conductivity so that heat generated by the conductor is transferred with very high efficiency to the jacket, the cylinder and the water. Taking into account the specific heat capacity of water, the 1475 watt heater, a calculation of time required to boil the entire 1.2 liters should be processed in approximately 6 minutes, for 100% efficiency. The Technivorm does it in 6.5, leaving just 30 seconds for thermal inertia to heat the element, jacket, cylinder and 100ml of water before boiling starts. In this sense, the KB-741 is first truly “green” drip brewer we have seen, and it shuts down the high-power heater automatically using a float switch as soon as the beaker of water has been emptied, so there is almost no wasted energy in this little gem.
Brewing and dwell time
The last variable is the length of brew time, or dwell time the [properly heated] water is in contact with the ground coffee. The Technivorm has three output valve positions in the filter basket: Closed, 50% and 100% open.
Safety and Quality
This product is very well designed for performance, safety and of the highest quality of materials and workmanship. All equipment grounds are compressed mechanical connections, and several safety ground terminations are redundant. All connections are crimped gas-tight with high compression tools and dies. Connections are high current safe, and will not fail from temperature cycling fatigue. The heating element has directly bonded thermal cut-outs at 145 Deg C (in case of mineral scale build up) as well as a catastrophic thermal cutout at 260 Deg C in case the float switch fails, AND the heater is turned ON w/o water in the reservoir. Intelligent use of high grade materials provides a safe, quality product which should last for many decades.
|Note direct safety electrical ground connections all with shielded compression fittings.
|The indirectly heated instantaneous heater, heats the OUTSIDE of the cylinder that holds 100-ml of water INSIDE.
|260 Deg C and 145 Deg C safety thermal switches, ceramic base with high-compression electrical fittings.
|The business end of the brewer is a very high efficiency German-made heater.
See technivorm data which reaches brew temperatures of 200 Deg F quickly and maintains proper brew temperature throughout the cycle, regardless of batch size. Several other brewers, also shown, brew at various temperatures, depending on batch size, and many do not reach proper extraction temperatures. Please click here to view more information on this topic.
Copyright 2007 George Howell Coffee Company. All Rights Reserved.