Posted Wed Apr 2, 2014, 12:42pm Subject: Re: What is the relationship between the grind setting and coffee flavor?
Ok, I was aware of the EK-43 and VST baskets, but somehow missed the work done on the 'coffee shot'; brew strength coffee from espresso machines.
Really you don't need to buy a new grinder and basket to explore this range to get well balanced extraction or follow his exact recipe on brew strength. I would love to try one of these and will look it up when I get the chance, but would encourage those interested to explore the brew ratio range even without the 'special equipment'.
I looked up where I was working this several years ago; 15-18gr dose, 5-6oz cup in +-30 seconds was working well. Work to get the grind/dose/extraction rate balanced for the desired strength and a balanced cup, not under or over extracted; much like any good cup of coffee. The aeropress (with fine mesh filter) cannot develop enough pressure for the fine grind and shorter brew times. It clogs and so forces a longer brew time/coarser grind. (...and it is mostly immersion vs. 'pass through' brew method.. if that matters?)
I wonder though, does an Hx machine have enough hot water in reserve to pump 6oz of water without the brew temp dropping significantly?
AustinJerry Senior Member Joined: 16 Apr 2013 Posts: 20 Location: Austin, Texas Expertise: I love coffee
Posted Fri Apr 4, 2014, 4:36am Subject: Re: What is the relationship between the grind setting and coffee flavor?
Who would have thought that my simple question would have generated such interesting conversation! Thanks for all the input.
I am nowhere near as expert or obsessive as most of you, but I have been running some experiments and measurements over the last week. I started out with a relatively fine grind (16 on the Baratza Encore), and experimented with other grinds all the way to 24, which is fairly coarse. The flavor difference between the two extremes is obvious too me (16 producing almost too strong a flavor, while 24 was weak and without much flavor). I finally settled on the mid-point (grind setting 20), which produces a flavor and strength that is pleasing to me. Here are my measurements:
- Water 34 Oz (six cups on the Bonavita scale) - Coffee 48 grams of beans for a 1.4 grams/oz dosage (somewhat short of 1.75 g/oz, which I have seen as the dosage recommendation) - Brew time 4 minutes 45 seconds (no control here--that's how fast the Bonavita processes 34 oz of water)
So, what continues to elude me is how to assess where on the Brewing Control Chart my resulting cup of coffee lands. It tastes to me like the "golden cup", but I would be interested in some feedback.
BTW, I tried using my TDS meter, but that didn't work very well. The meter seems to be sensitive to temperature, and even letting the coffee cool down produced erratic measurements.
Well, if the result is pleasing to you, it doesn't really matter what the numbers are, so long as you can consistently repeat good brews.
I'm not used to working in oz, but you seem to be around 50g/l which means that you may be a little weaker than the SCAA ideal box (maybe you're in the region of 1.05% to 1.18%-ish TDS for a gold cup extraction?), but the important factor is getting in the yield range (18-21%), where your coffee isn't weak & acidic, nor bitter/drying/smokey. The SCAA chart is centred around 56g:34oz., but brewing above that coffee weight is also pretty typical (60-65g).
Your experience with TDS meters reflects my own. Pour a little coffee into a shot glass/cup, deep enough for the meter, let the coffee drop to room temp then take a few measurements, being careful to keep the probes/casing from bottoming out in the glass/cup. You'll probably need to make several brews, same weights, same coffee & grind, to get an average value. Even then, it will more likely be a personal reference for yourself, than a true reflection of chart values.
Some scales accurate to a milligram and carefully dehydrating some coffee samples may get you closer, if you're not concerned about real time readings? A coffee refractometer & app from VST is expensive (relative to the methods discussed above), but given the savings in time, wasted coffee samples & accuracy, it makes more sense if you really want to know your yield. Maybe there is someone near you who owns one?
The VST coffee refractometer is the tool of choice but it is probably out of your price range. Inexpensive optical sugar refractometers are considerably less accurate. If you can find one within your budget that resolves to 0.1% Brix (roughly 0.1% TDS) you might find it useful. Another option is a sugar hydrometer. For $25-40 you can buy one that resolves to 0.1% Brix. But you need a lot of coffee to float the hydrometer and a lot of time to cool it all down to the measurement temperature. They are very temperature sensitive. I've used a $25 pocket scale and my kitchen oven to successfully measure to an accuracy approaching that of a VST coffee refractometer but it takes me about 2 hours to get a reading. Most people just use their taste buds. While gold cup extraction is usually necessary for balanced coffee it isn't by itself sufficient. That is to say, you probably won't have good coffee if you're out of the target extraction range but you can be in the target and still have bad coffee. There are so many ways to make bad coffee.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.