Dawn Chan Kwun Ho, the Barista Champion of Hong Kong just got into the final top 6 of the WBC using some interesting techniques. He's also using what in my opinion is the second greatest coffee I've ever tried (Colombia Cerra Azul Geisha), second only to Semeon Abay from Ninety Plus in my mind.

He did several unique things, but what jumped out at me immediately was his use of a sous vide bath to pre-warm the (vacuum sealed) whole beans before being ground on an EK. He said he found his results increased solubility to a whole 1% increase, not a trivial amount.

Curiosity got the best of me. I had just recalibrated my Bunnzilla to grind fine enough for espresso. I broke out the vacuum sealer and weighed out 18g of a light roasted Ethiopian (12.8% weight loss, very light city roast). First attempt was way too fast, so I did it again. A water bath of 170°F was used, and the bag sat in the bath for about 5 minutes or so.

Second attempt with a finer grind and a slightly higher dose, still very fast flow, but acceptable. The shot was amazing. It was like beautifully brewed coffee, just stronger and more mouthfeel. Zero sourness, extremely enhanced sweetness, just delicious. My third attempt with the burrs right at touching and I dosed 17.5g. Shot still flowed fast, but I restricted the pressure of the spring manually to control the flow.

This made another absolutely amazing shot. It might be the best extracted espresso I've ever made to date. I can't do this for every shot I make, but I think it might give us a glimpse at what the Mythos One might be able to do. I imagine a large flat burr is equally key to this effect. It's definitely worth a try if you have a large water bath and a good thermometer, you can get close enough to approximate what he did, without the expense of a sous vide.

Did you try a comparison to non-heated beans?

Yeah, it was the same coffee I've been pulling earlier today. Night and day difference.

Since the last post, I did one last shot and called it a day. The burrs were rubbing, the shot was the best I've ever pulled from any of my machines. It was like cranking the amplifier up to 11 on sweetness and flavor, leaving behind anything harsh or sour. I'll continue to test out very light roasts and see what comes of it. I wish it was a bit easier to accomplish, but it's not. Still worth trying though.

Any specific details on time and temperature for the water bath? I've got a sansaire and some red bird blue jaguar to experiment with. Thanks!

Really interesting, for sure. I wonder how the people who swear by using beans right out of the freezer are going to respond to this?

Also of interest to me is your comment about the Cerro Azul. I received a gift of those beans from Nossa Familia as a thank you for supporting them in my posts on here and CG. Their note basically said, it won't make great espresso, but for press and pour over it is mind blowing. I've only made press with it (my typical brew method for s.o. beans), and agree it's fantastic. I just love the strawberry dominance in the finish.

new2espresso wrote:Any specific details on time and temperature for the water bath? I've got a sansaire and some red bird blue jaguar to experiment with. Thanks!

Here's a link to his WBC presentation.

http://livestream.com/worldcoffee/event ... s/83609529

He held the beans at 113°F ( 45°C)for 40 minutes before grinding. I just double-checked the video and realized I had misunderstood what he said. I thought I heard 170. My beans were in the water bath at 170°F for about 2-3 minutes. I'd rather attempt to replicate his method, so I'll do it again tomorrow.

Either way, there's certainly something to what he's using. The same coffee, same dose, same grinder on the same machine without doing this was worlds apart. There is a full, weighted sweetness, toned down acidity (at least any part that contributes harshness or unpleasant brightness) that wasn't present without warming the beans.

It will be fun to play around with. But from the hip, if this holds true over many other coffees, as a tool for better extraction, I haven't found one.

emradguy wrote:Really interesting, for sure. I wonder how the people who swear by using beans right out of the freezer are going to respond to this?

Also of interest to me is your comment about the Cerro Azul. I received a gift of those beans from Nossa Familia as a thank you for supporting them in my posts on here and CG. Their note basically said, it won't make great espresso, but for press and pour over it is mind blowing. I've only made press with it (my typical brew method for s.o. beans), and agree it's fantastic. I just love the strawberry dominance in the finish.

I'd be interested in hearing if you try something similar. The specific roast of the Cerro Azul was from Victrola.

When something has this big of a positive impact on the shot, it's hard not to get exuberant about it. But I can easily say, no grinder upgrade, no espresso machine change or method of prep has ever given me this significant of an improvement than trying this. I can only imagine what it would do to a light floral geisha. The Ethiopia Gedeo Worka I used was jam-packed with intense, heady, floral aromatics. The finish clung to my palate for 15 minutes and was a delightful reminder.

I don't know if I can keep doing this, just to make espresso, but maybe it would be worth it to see if something like a folded up electric blanket with a few towels or something used as padded spaces between the blanket and coffee would yield similar results? I can use a bare wire thermocouple in a bed of beans that won't have to be vacuum sealed, and see if I can keep temps somewhere in that range. If I can closely approximate that, I might play with it some more.

For me, the challenge was getting the bag dried off, cut open and into the hopper as quick as possible. The Vac-Saver bags really tighten up against the beans even more when put in a water bath, so getting the beans out of the bag was a bit of a challenge. While I wouldn't do it on a daily basis, if I could put the beans in my smallest canning jars and warm several batches up, nestled in an electric blanket and be able to just grab one and grind, I'll be more inclined to look into the Mythos One even more.

For what it's worth, the coffee he used also won the Roaster's Choice in Boston at the 2013 SCAA event, roasted by Equator. It's a phenomenal geisha, the best geisha I've ever tried.

A significant amount of the effort sounds like the vacuum sealing. I have a sous vide water bath and am thinking that small Mason jars would probably do the trick quite well, especially given the amount of time that the beans are exposed to that moderate level of heat.

Or I may just put some folded up microfiber dishtowels I normally use for cleaning up my gear, and lay them on the top tier of my Izzo Leva. It's slightly warm there, nowhere near as hot as the bottom shelf. I can put a thermocouple in a towel and monitor it's temp for a bit and see what it reads. It would be quite convenient to lay out a few pre weighed shots in small bags and just leave them there at the beginning of my brewing session and just grab one as I need it.

kwantfm wrote:A significant amount of the effort sounds like the vacuum sealing. I have a sous vide water bath and am thinking that small Mason jars would probably do the trick quite well, especially given the amount of time that the beans are exposed to that moderate level of heat.

You'd think I was BS'ing otherwise, so here's a picture to show my surprise.



The top tier of my cup rack was only 91°F. The main shelf stabilized right at this temp within about 3 seconds of setting it up and stayed there. It wandered between 112.5 and 114. I think I know what I'm doing in the morning. I'll even potentially risk wasting a few shots worth by setting a few up in my small mason jars tonight, then adding a few more tomorrow when I get ready to start my morning coffee routine.