Going above 212*F/100*C during boil - Page 3

bessieflames · 02-03-2012, 10:12 PM

Quote:

Originally Posted by passedpawn

I don't think DMS is an issue with extract.

I re-read the OP. I missed that it was a kit. I don't think DMS is a big problem with extracts, but there are other reasons not to put the lid on such as boil-overs. It just doesn't seem like a good practice.

Ultra-Medic · 02-03-2012, 10:25 PM

Quote:

Originally Posted by bessieflames

I re-read the OP. I missed that it was a kit. I don't think DMS is a big problem with extracts, but there are other reasons not to put the lid on such as boil-overs. It just doesn't seem like a good practice.

Been there. Lids will result in boil overs. First batch held a near-boil at 190-200 degrees. Was 5gal on electric coil stove. Turned on the second burner, decided to add the lid... spent the next morning learning what cleans burned wort from a stove.

End result? Awesome brown ale. So don't worry so much and be patient.

**passedpawn** · 02-03-2012, 11:33 PM

Quote:

Originally Posted by NordeastBrewer77

a harder boil simply means faster evaporation of the water.

To be specific, it's vaporization, not evaporation (well, maybe a little evaporation, but it's not significant in this case). The reason I point this out is because when you get into the math of it, "heat of vaporization" is what is driving the water into the air. For electrical brewers, things can be surprisingly (pleasantly!) mathematical and deterministic. Evaporation happens at the surface, and is subject to dew point and other ambient effects, while vaporization is driven from the bottom (flame) or the element.

(I'm not trying to start a fight here, just want to make sure the terms are correct... I know what you meant).

**MuchoGusto** · 02-03-2012, 11:50 PM

As a former high school science teacher, steam is a technical term for water water vapor.

**passedpawn** · 02-03-2012, 11:59 PM

Quote:

Originally Posted by MuchoGusto

As a former high school science teacher, steam is a technical term for water water vapor.

Mr. Tremble? (my HS chemistry teacher, great guy, one of the greats that made me)

pelipen · 02-04-2012, 12:18 AM

Impurities raise the boiling point and lower the freezing point of a pure substance. you can calculate how much table sugar would be required to increase the boiling point by 1 C. It's going to come out to be a huge amount.
Two things are true:
1) the boiling point of wort is higher than 212 F at one atmosphere.
2) it's totally insignificant

You can boil water in a paper cup. You can also burn a hole in a paper cup with water in it. How you measure matters.

**BrewKnurd** · 02-04-2012, 02:19 AM

Quote:

Originally Posted by pelipen

Impurities raise the boiling point and lower the freezing point of a pure substance. you can calculate how much table sugar would be required to increase the boiling point by 1 C. It's going to come out to be a huge amount.
Two things are true:
1) the boiling point of wort is higher than 212 F at one atmosphere.
2) it's totally insignificant

According to this handy-dandy calculator, a 1.048 wort would experience a boiling point elevation of a whopping 0.5 degrees celsius!

**jeepinjeepin** · 02-04-2012, 02:21 AM

Quote:

Originally Posted by passedpawn

To be specific, it's vaporization, not evaporation (well, maybe a little evaporation, but it's not significant in this case). The reason I point this out is because when you get into the math of it, "heat of vaporization" is what is driving the water into the air. For electrical brewers, things can be surprisingly (pleasantly!) mathematical and deterministic. Evaporation happens at the surface, and is subject to dew point and other ambient effects, while vaporization is driven from the bottom (flame) or the element.

(I'm not trying to start a fight here, just want to make sure the terms are correct... I know what you meant).

Latent heat of vaporization.

**passedpawn** · 02-04-2012, 02:35 AM

Quote:

Originally Posted by jeepinjeepin

Latent heat of vaporization.

right. I don't remember the number, but it's an easy conversion from watts to know how much water gets vaporized per minute/hour from a 5500W element.

I'm too lit to do the math. I've done it before on here, to a huge round of silent applause (ugh). One of the joys for electric brewers is the absolute predictability of the system.

**jeepinjeepin** · 02-04-2012, 02:42 AM

Quote:

Originally Posted by passedpawn

right. I don't remember the number, but it's an easy conversion from watts to know how much water gets vaporized per minute/hour from a 5500W element.

I'm too lit to do the math. I've done it before on here, to a huge round of silent applause (ugh). One of the joys for electric brewers is the absolute predictability of the system.

It's amazing what you can do with hard numbers. With your wattage, ambient temp, humidity, etc you could exactly figure boil off among other things.