# How does roast type affect grinding the coffee?



## rgoodcoffee

Hi,

just a quick question here - does the roast of a coffee affect how it will grind? By this i mean if some coffee beans have been dark roasted do they behave differently in a grinder than a lightly roasted bean would be? Or is it a case of every bean should grind the same in the same grinder on the same setting?

thanks in advance!


----------



## The Systemic Kid

Degree of roast affects level of grind needed. Darker roasts are more brittle and shatter more easily during grinding. It's not only degree of roast that affects grinding - bean varietal does too - some varietals are smaller than other others - some are harder. Age, i.e. length of period from roast date also affects grind parameters too.


----------



## rgoodcoffee

The Systemic Kid said:


> Degree of roast affects level of grind needed. Darker roasts are more brittle and shatter more easily during grinding. It's not only degree of roast that affects grinding - bean varietal does too - some varietals are smaller than other others - some are harder. Age, i.e. length of period from roast date also affects grind parameters too.


thats really interesting - thanks! what do you mean by 'level of grind'? would you need your grinder on a finer setting for harder beans/lighter roasted bean?

thanks


----------



## The Systemic Kid

Generally, you grind coarser for darker roasts and finer for lighter. Remember, the point of the exercise is to extract as much of the coffee solids present in the bean - the maximum is around 30% - the other 70% of the bean is cellulose. Darker roasts give up their dissolvable coffee solids more easily than lighter which is why you end up grinding finer for lighter. Where the bean comes from, the altitude it was grown at, bean varietal will also impact on how easily it is to extract the coffee solids but, generally, degree of roast is probably the predominant factor.


----------



## rgoodcoffee

The Systemic Kid said:


> Generally, you grind coarser for darker roasts and finer for lighter. Remember, the point of the exercise is to extract as much of the coffee solids present in the bean - the maximum is around 30% - the other 70% of the bean is cellulose. Darker roasts give up their dissolvable coffee solids more easily than lighter which is why you end up grinding finer for lighter. Where the bean comes from, the altitude it was grown at, bean varietal will also impact on how easily it is to extract the coffee solids but, generally, degree of roast is probably the predominant factor.


Very interesting info, thanks a lot!!!


----------



## jefferson17

Assuming that you have a decent burr grinder AND you are doing espresso, then the grind is simply adjusted for each bean differently to allow the proper extraction. With a good grinder and espresso machine, the proper extraction is usually between 25-30 sec - and the grind adjusted to achieve this - along with a consistent tamping technique. I have a "basic" setting that I start with for my first shot with a new batch of coffee (all home roasted), and I'll adjust a bit more coarse or fine depending how the first one goes. As the coffee ages, I'll often dial-it in a touch more fine, about 1 notch every 2 days after the initial 3-5 rest days.

But if all you are doing is drip or french press, the exact grind isn't remotely as sensitive. Water temp and immersion time will factor in more. You didn't state what you are doing - coffee or espresso - feel free to clarify and ask more.

Good luck!

J.


----------



## MWJB

jefferson17 said:


> But if all you are doing is drip or french press, the exact grind isn't remotely as sensitive. Water temp and immersion time will factor in more. You didn't state what you are doing - coffee or espresso - feel free to clarify and ask more.
> 
> Good luck!
> 
> J.


Drip isn't so sensitive, because the speed you add the water can be tuned to normalise flow time & extraction. You are also constantly replenishing with hot brew water. French press is a bit more finicky, especially with smaller brews, too coarse and your extractions will always be low, no matter how long or hot you steep (the press cools from start & even using brew water at boil might not provide much over 90degC at the start, once coffee & water are combined).

Very dark roasts might need a coarser grind to mitigate silt. Even at an apparently similar roast level, Kenyans may extract further than say central American naturals/honey processed coffees.


----------



## hun_kab

Darker roast can sometime taste more concentrated because of the bitterness


----------



## Missy

hun_kab said:


> Darker roast can sometime taste more concentrated because of the bitterness


Say what now?

Darker shouldn't taste any more or less bitter than a light roast. If it does you are getting something wrong in the process.


----------



## MWJB

Missy said:


> Say what now?
> 
> Darker shouldn't taste any more or less bitter than a light roast. If it does you are getting something wrong in the process.


Lighter roasts are often (but not always) sweeter, but also darker roasts can be more intense in flavour at the same brew ratio. A longer brew ratio for darker roasts can address this.


----------



## garydyke1

Missy said:


> Say what now?
> 
> Darker shouldn't taste any more or less bitter than a light roast. If it does you are getting something wrong in the process.


I disagree. The cupping table reveals darker roasts (of the same coffee) as having more bitterness


----------



## Missy

garydyke1 said:


> I disagree. The cupping table reveals darker roasts (of the same coffee) as having more bitterness


 thanks. I realise I had strayed into assumption on my limited understanding and experience.


----------



## garydyke1

Missy said:


> thanks. I realise I had strayed into assumption on my limited understanding and experience.


But one persons 'darker roast' is another persons 'properly developed roast' is another persons 'medium roast'.......there is a level of subjectiveness / personal preference


----------



## Missy

garydyke1 said:


> But one persons 'darker roast' is another persons 'properly developed roast' is another persons 'medium roast'.......there is a level of subjectiveness / personal preference


I always thought bitterness was an "error" and one less likely with a darker roast. It's fascinating. Once I'm working again I'm going to have to invest in some cupping and palate training stuff.


----------



## garydyke1

Missy said:


> I always thought bitterness was an "error" and one less likely with a darker roast. It's fascinating. Once I'm working again I'm going to have to invest in some cupping and palate training stuff.


Sugars get caramelised during roasting, think caramel in a pan . Once you get past dark golden caramel you hit bitter sweet


----------

