first all grain

[mb]

just pitched the yeast on all grain brew #1, Daab's mini-mash bitter

started at 11 this morning so i've made a bit of a meal of it, but all good fun and i reckon i can knock an hour or so off hours off today's effort learning from my mistakes.

re boiling: how hard a boil should it be? my hob struggled to keep 5-6L at a rolling boil with the lid off (would it hurt if i kept the lid on?). that said, i've undershot and only got about 4L to ferment so it evaporated a fair bit even at a semi-simmer.

it tasted promising going into the FV, so fingers crossed.

next up - tomorrow if it isn't sunny, sunday if it is - a mild

[David Edge]

my hob struggled to keep 5-6L at a rolling boil with the lid off (would it hurt if i kept the lid on?). that said, i've undershot and only got about 4L to ferment so it evaporated a fair bit even at a semi-simmer.

A gas hob's 2kW so at full chat it will evaporate four litres per hour. You got away lightly. Our first barley wine was 1.200 at end of boil and had to be diluted back to 1.100. Made a darned good beer.

[Ianb]

my hob struggled to keep 5-6L at a rolling boil with the lid off (would it hurt if i kept the lid on?). that said, i've undershot and only got about 4L to ferment so it evaporated a fair bit even at a semi-simmer.

A gas hob's 2kW so at full chat it will evaporate four litres per hour. You got away lightly. Our first barley wine was 1.200 at end of boil and had to be diluted back to 1.100. Made a darned good beer.

I am intrigued, David, how you can equate the rated net input of a hob to a specific evaporation rate. Surely this depends on the surface area of the boiling product, the thermal losses from the other parts of the vessel, the thermal loss of heat escaping around the vessel and not actually heating the product and the energy input?

I'm not being deliberatley pedantic, but unless I have missed something (which is feasible, It is saturday evening, and SWMBO has gone to Londinium for the day - wife away, Ian WILL play!!! ) the quoted evaporation rate will be specific to your system.

[David Edge]

I am intrigued, David, how you can equate the rated net input of a hob

I didn't. I put a 15 litre (brim) stockpot on the cooker and measured the rate of temperature rise and hence the net input to the pot. How far out do you think the estimate of four litres is for a typical UK domestic kitchen?