The Yama Vacuum Brewer is a stovetop model from Japan that resembles the long-gone Silex and Cory glass models made in the U.S. for over 50 years. It is a utilitarian vacuum-syphon brewer that can stand up to daily use. It is available in 5 cup and 8 cup sizes.
Like other vacuum brewers, the coffee brewed in this maker has great body, without the sediment you get in a French press. The 5 cup model is makes is 20 oz. The 8 cup makes 32 oz. he 5 cup model is fine for 2 people, 3 in a pinch, 4 if you are using "polite cups" and 5 in times of great duress. The 8 cup model has a more aesthetic, rounded glass parts.
It has a cloth filter that fits over the metal filter assembly - you can also use a Cona filter drainer rod with the Yama - though be careful with the grind when you do this. The lid doubles as a stand for the funnel (top glass part), and it comes with a spare cloth filter and a burner wire grid for use on an electric stove.
******We have heard from some folks that the glass drainer can get clogged and if the pressure is not released, it can cause the glass bowl to implode. Whenever you are brewing with the replacement glass drainer, be sure to watch the brewer, and if it stalls (i.e. the coffee does not pull down to the bowl), just wiggle the drainer to release the pressure. If it does not release - relight the flame on the bottom bowl, the increased temperature ought to equalize the pressure.*****
Here is a step by step pictorial to brewing in the Yama vacuum brewer. Here I am using the 5 cup model with the Cona glass filter rod. This is a great day-to-day, low cost vacuum brewing setup. Undoubtedly, if you brew this way you will find your own method to brew, but here is the way I get great results..
okay, here we are ready to go. on a gas stove, you do not need the wire grind between the yama bottom bowl and the burner. the top bowl sits in the stand
it is so much easier to use hot water. preheat good spring water or filtered tap water. Use a pot on the stove or an electric kettle as shown above. Fill to the desired line. I feel that making full pots (ie 5 cups in the 5 cup model) is best.
once the water is in, seat the top bowl on with a slight twist. if the seal between top and bottom is not good, no syphon or vacuum action is possible.
make sure the filter is in place and add the coffee to the top. in this demo, i am not using the yama filter cloth-disk assembly, but instead the glass filter rod. both work well.
okay, we are ready to brew, just turn on the heat...
okay, the heat is put on the lowest setting, or nearly the lowest. if you want to brew starting with cold water, you will need a bit more flame, but never on high! again, i think it is far better to start with hot water, which means the syphoning to the upper bowl is immediate.
to stir or not to stir? You simply don't want dry grounds to form "islands" that fail to infuse with the hot water, but frankly a yama will tend to syphon so vigorously that it will roil all the grounds into the brew.
stirring does help to break up the crust on the top ... you simply want the grounds to mix throughly with the water. don't stir too much ... like 5 times. if you use the cona rod, don't knock it as you stir.
the water has syphoned upward. in this demo it took under 1 minute. there is always a bit of water that remains below, this is normal. you may see the "boiling" action in the top funnel, but this is pressure action, not actual boiling; vacuum brewing never boils coffee, it's just not possible to exceed 212 f.
steep time? keep the flame on the lowest setting. while you want a total of about 4 minutes steep time with brew methods, i get best results with leaving the yama (or bodum or cona) to steep for only about 1 minute. why? well, it has already steeped 1 minute as the water syphons up, and it will be another minute before it is all vacuumed down.
when you are ready to start the vacuum, turn off the flame. usually, i move the brewer off the burner i heated it on, because residual heat slows the vacuum process
we are about half way in this picture. ideally i like it to vacuum down in 1-2 minutes.
at the end of the vacuum
remove the top funnel, and place it in the stand. do not try to heat the coffee at this point, trying to keep it warm. that ruins it.
enjoy the results!