Posted Mon Mar 4, 2013, 7:51pm Subject: Re: New at grinding at home
RDT works well even for the electric burr grinders. Just a thought. 1 drop per 14g of beans.
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
pstam Senior Member Joined: 27 Jan 2004 Posts: 2,305 Location: Beijing Expertise: Professional
Espresso: ECM, SAN MARCO, EURO 2000 Grinder: MAZZER Vac Pot: YES Drip: YES Roaster: YES, HOME STYLE
Posted Thu Mar 7, 2013, 11:08pm Subject: Re: New at grinding at home
jliedeka Said:
Getting the perfect grind just takes a bit of trial and error. If the filter doesn't drain fast enough or the brew is bitter, you probably need to go coarser. If it drains too fast and the brew is more sour, go finer. Jim
That is it. I believe that it is the normal way of adjusting the grinder settings. But one thing is different for me. "If it drains too fast", the coffee brew will be tasted light, not strong enough, but not sour. Only for espresso, it can be sour for courser grinding, as I tasted and understood. For brew coffee, I suppose that one can change the water temperature gradually to find the best flavor while keeping the grinding size the same.
One more question, do you believe the grinding size should be changed according to the amount of coffee grounds? For 10 or 20 grams of coffee beans, do you use the same setting of coffee grinders?
Peter in Beijing ------------------- http://www.kaffa.cn/ ------------------- I am looking for the way and the place to extend our trainning courses.
Posted Fri Mar 8, 2013, 9:50am Subject: Re: New at grinding at home
I've actually been experimenting with adjusting grind size to batch size. When I brew in a Technivorm, I have to stop the brewing for a minute to let it drain. The funnel threatens to overflow. That's using what looks like a pretty coarse grind and around 65 grams of coffee. I haven't hit on the right batch size/grind size to let it brew unattended.
msboo Senior Member Joined: 10 Nov 2012 Posts: 107 Location: Kentucky Expertise: I love coffee
Grinder: Baratza Virtuoso Drip: Bonavita
Posted Fri Mar 8, 2013, 5:03pm Subject: Re: New at grinding at home
Grinding a little finer for smaller batches may help, as long as you don't get a bitter brew. I need to experiment myself. I'm having to grind at a finer setting on this Virtuoso---concerned that it's not properly calibrated as should have been at the factory (purchased new!). I've read here where, for smaller batches, other Bonavita owners let water flow for 1 to 1 1/2 mins, manually turn off for 1 min or so, then turn back on to finish brewing. I'm surprised to hear a Technivorm would possibly overflow with that amount of coffee ground fairly coarse but I don't have any experience with that brewer (although VERY tempted to get one!).
Anecdotal observations are that home roasted tend to have more static, but it isn't a hard rule. General thinking is that underroasting will tend to have less static, more static in the City to Full City+, but less static and more oil sticking in the darker roasts.
Some observations are that fresher coffee, or coffee with more bloom is also coffee that tends to have more static when ground, so older coffee may have a lower tendency for static.
Some thinking is that chaff has some to do with it. There's also a hypothesis that moisture content of the roasted coffee (which ranges from 0.25% to 7%) may also be a factor.
Relative humidity, which changes on average during the season, depending on how much heating your home needs or AC it needs in the summer and winter seasons, is also thought to have an effect. Higher relative humidity tends to have less static.
There's some thoughts that the type of burr, coatings, etc. have something to do with static too.
None of these are completely exception-free rules.
I've personally found partial support of these. Most of the time, static is maddeningly unpredictable. I see it come and go on a single batch, as it ages. There's just a general correlation to relative humidity.
The one thing we do know is how to make it go away for good. I've found RDT, the "Ross Droplet Technique", is VERY effective at eliminating static. For me it involves adding 1 drop of water from a pipette per 15g of roasted coffee beans, shaking the beans, then tossing them into my grinder (whatever grinder it is).
Here's the start at the "why" of static (Tutorial on static electricity in grinders), but while it's a great start at potential mechanisms for static, it still doesn't create prediction of when we might or might not see static during grinding.
A broad brush model that might be proposed would (in my mind) look like:
Static Index = f(Humidity)+f(moisture in coffee)+f(coffee age)+f(chaff content)+f(roast level)+f(gas level of the coffee)+.... ...
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
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 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.
= No New Posts since last visit 