ODI3

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I read many people with 5500w elements tend to reduce the boil to 70% after the boil has started, I assume this is to reduce boil off and to avoid boil overs. But is it actually better to have a small rolling boil or an absolutely maximized one?


The Benefits of maximized boil:
Maximized boil maximize the amount of dms being boiled off (i think?)
Maximized boil would have a higher boil off rate and require more water to be sparged or added in biab. Since the water/sugar ratio is higher, I assume this would increase extraction efficency.

The drawbacks:
increased cost for either propane or electricity
Increased water fumes in the air (might cause exaust problems if inside)
Scorching possibility?

What do you guys think?

CS223

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Having experienced both and made beer from both, I'd say that an over heated boil is not beneficial. You can use a higher water to grain ratio and just boil longer according to your boil off rate. Add your hops accordingly during the last 60 minutes. My non-scientific opinion is that a higher boil (foamy) creates a greater opportunity to caramelize the sugars, runs the risk of scorching & creating off tastes, boils off essential oils from hops that you might not want to lose or at the very least altering the flavor profile of the hops. A boil that is just strong enough to churn the wort and create evaporation IMHO, is all that's required and for me that's about 55% power on a 5500W element. If you want to experiment with higher water to grain ratios have at it, just do a good job of measuring your boil off rate and make a calibrated stick, spoon whatever to get an accurate measurement of the wort in the kettle so you know how long to boil to get to your first hop addition & 60 minute countdown.

__________________
My BIAB RIMS E-Brewery Build : My spunding valve build : My shamelessly cheap stir plate build : Cereal Killer Mill Tear-down : My Temp Controller Build : My awesome LHBS

Of all the things I've learned from HBT the single most important lesson has been: RDWHAHB.

TyTanium

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False. Gravity goes up, but volume goes down. Efficiency remains the same. Only way to change efficiency is to add/remove sugar...adding or removing water doesn't do anything.

CS223

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I think what he means is using more water during mashing, i.e. higher water/grain ratio and/or sparging with more water to better rinse the grains with the intent of extracting more sugars.

__________________
My BIAB RIMS E-Brewery Build : My spunding valve build : My shamelessly cheap stir plate build : Cereal Killer Mill Tear-down : My Temp Controller Build : My awesome LHBS

Of all the things I've learned from HBT the single most important lesson has been: RDWHAHB.

ArcLight

Recipes 

I think the more vigorous boil also creates somewhat darker beer, due to Maillard reactions. It may affect taste (like toast), due to more melanoidins.

>.Maximized boil maximize the amount of dms being boiled off (i think?)
If you are doing All Grain, then yes. It's not a consideration for extract brewers.

TyTanium

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Ah, check. Agreed.

jCOSbrew

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A slow boil and a vigorous boil are the same temp (approx 212 deg F). How can the color or flavor of the beer be effected?

ludomonster

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The water is not the same temperature throughout the pot. The water closer to the heat source will be warmer than the water at the top. You might not have the same gravity throughout the boil, especially with liquid extract.

A more vigorous boil will also be hotter than 212. As water boils off, it concentrates the wort. Specific gravity rises, creating a higher boiling point. You aren't going to get to candy temperatures unless you boil for a few hours.

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Bottled: Old Freckled Men, Berlin Mart Cider, Creamer Ale II
English Mother****er, Do You Drink It Pale Ale
C4 Pale Ale (Centennial, Challenger, Cascade, Citra hopburst)

Gone: Honeybadger Wheat Ale, Bad Amba Jamma, Badder Amba Jamma, Slam Dunkelweizen, Creamer Ale I, Robust Porter

SnidelyWhiplash

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any scientific fact if a slight difference in temp actually affect flavor? any chemical reaction rate is a function of absolute temperature, and a few degrees difference over an hour is going to be extremely small. when you first hit a boil the water near the top will still be a fair bit cooler, but a moderate boil over a long time should keep the pot mixed enough to be very close.

ludomonster

Recipes 

There's some empyrical data about the when carmelization occurs as well as the change in reaction rate. However, carmelization is a poorly understood process involving many chemicals, and it would be difficult to give you an equation. It's also a function of pH. What we do know is that when the malt sugars start to carmelize, the temperature is above 356F.

Here's some info.

When brewing, we're concerned with maltose, sucrose, fructose (when working with fruit), and glucose.

__________________
Bottled: Old Freckled Men, Berlin Mart Cider, Creamer Ale II
English Mother****er, Do You Drink It Pale Ale
C4 Pale Ale (Centennial, Challenger, Cascade, Citra hopburst)

Gone: Honeybadger Wheat Ale, Bad Amba Jamma, Badder Amba Jamma, Slam Dunkelweizen, Creamer Ale I, Robust Porter