Brew Day Questions

[Doingatun]

Hi, I wonder if any one could help and answer a few questions I’m struggling with
preparing for my first all grain brew tomorrow, probably should of picked something simpler?

Grolsch 23 L Brew Graham Wheeler BCEB At Home - page 130

Lager Malt 4.13kg
Flaked Maize 730g
Saaz Hops 30g
Hallertau Hops 20g
Irish Moss 10g
90 min Boil

Is 12L of water sufficient for mashing in a (cool box MT) 4.86kg of grain/maize?

Can I step mash in my cool box MT by adding hot water 50c-20 min, 62c-45min, and 70c-45min?

How much sparging water should I prepare? Thinking of 18L? that’s 30L in all only got a 25L boiler 30L is at the brim.

Using an Immersion cooler I know to put it in the boiler 15 mins before end of boil to sanitise, when the boil is complete rest for 30 mins. Do you then cool with the cooler in the boiler or put it in the FV when full to cool the hot wort.

[mysterio]

Good luck with your first AG... Nothing wrong with doing a lager, but it does mean you'll be waiting a while before you can sample it. Make sure you note your starting gravity so you can calculate your efficiency and adjust your grain bill for your next brew.

1) Yeah, 12L will give you a water grain ratio of 2.47 L/Kg which is ideal.

2) Step mashing is pretty difficult in a cool box. I've tried with just one step up and I had it right to the rim by adding water. It was difficult to measure the temperature because the mash was so thin by this stage. I imagine three seperate temperature rests would be impossible.

I wouldn't bother with step mashing. Lager malt these days is fully modified (I've emailed suppliers like Brupaks to make sure) which means there is absolutely no need for a 50C protein rest. In fact, it can damage the head retention & body when using fully modified malt. Under-modified malt which requires a protein rest is pretty difficult for the homebrewer to source these days.

The reason for the rests at 62C and 70C is to give a specific ratio of sugars and unfermentable sugars (dextrins, maltose, maltriose etc), and unless you can get these two rests at the specific temperatures then there's not much point. There is no increase in the 'quality' of the beer by doing these two rests; I expect this is the info they got from the brewery which they're passing on in this recipe. It is obviously much more important for Grolsch to brew the same beer each time.

I would go for a single infusion at around 66/67C. I've done lagers like this and they've turned out excellent but no doubt there will be differing opinions on this topic.

3) I usually sparge until I've got six gallons in the boiler for beers of that gravity then boil it down to five.

4) I think it's best to start chilling the wort immediately after the boil, inside the boiler. This way no extra bitterness is extracted from the hops and the aromatic qualities of the late hops are preserved. It also means the cold break gets left behind in the boiler; IMHO there is no need to rest it for 30 minutes. I used to chill inside the FV which meant the cold break would get churned around the beer during fermentation which gave me a problem with haze.

[Andy]

As DaaB mentions, don't underestimate the amount of sparge liqour you'll need. It's not as simple as 12L (mash) + 18L (sparge) = 30L (collected) as the grain will absorb liqour in the mash. Typically the grain will absorb 1L/kg so you'd only get 12L-5L (rounded) = 7L of wort out of the mash without sparging. To collect 30L then you need 23L of sparge liqour.

As for boiler size what I do is collect approx 25L in the boiler and collect extra wort into a big pot. I boil this extra wort on the stove and use it to top up the main boiler as the wort evaporates (top up after 1hr and additionally 15mins before end of boil).

If the mash running go below 1008 SG then it's time to stop sparging regardless of volume collected.

[Doingatun]

Thanks – Mysterio – DaaB – Andy

That’s a great help, now feeling more confident

[Frothy]

ahhh I've been looking for a grolsch clone - thanks DAT for the recipe.
May I ask please what the IBU and target gravity is for the recipe?

bear in mind for a lager you want a long & chilly ferment for that lager yeast
Primary ferment ~ 8oc 2-3weeks
Lager (conditioning) ~ 2oc 4-6 weeks
Filter, Pressurize, drinky drinky

best of luck
Matt

[Doingatun]

Hi, Frothy

ahhh I've been looking for a grolsch clone - thanks DAT for the recipe.
May I ask please what the IBU and target gravity is for the recipe?

No IBU mentioned, hope this helps?

OG 1048
FG 1011
ABV 5%
Bitterness 27 EBU
Colour 3 EBC

[mysterio]

EBU = IBU

[Frothy]

Excellent - thanks guys I've found another clone that uses N.Brewer for the Bittering hops & Hallertau for flavour, Saaz for Aroma but swings and roundabouts, will give this one a go.

Matt

[Doingatun]

Well first brew finished after 6hrs – single mash at 67c as advised using 12 L water with ¼ campden tablet heated to 80c poured into cold MT dropped to 72c, after doughing in 64c add ½ to 1 L boiling water to achieve 67c (bit of struggle) for 90 mins dropped 1.5c during mash despite being wrapped in sleeping bag – brewing in cold garage.

25 L sparge water plus ½ campden tablet, heated to 80c. Sparging slow lasted 45 mins used all sparge water and drained MT final runnings SG 1010/8, ended up with 30/32 litres boiled for 90 mins adding Hops, later Irish Moss and immersion cooler.

Yeast starter prepared as per Jim’s method (lager Yeast).

Cooler sat to low in boiler and after ¾ hr the lower half was cooled down and the top half remained hot, drained boiler left cooler running to reduce the surface temp as it lowered – FV 23.5 L of pale looking wort, temp 17.5c SG 1045 - recipe 23 L at SG1048.

Little or no activity with yeast starter, thought best to pitch anyway.

Larger Malt 4.13kg x 300/23.5 = 52.72

Flaked Maize 0.730 x 300/23.5 = 9.31

= 62.03

Efficiency 45/62 x 100 = 72.6% please correct me if I'm wrong

Expected FG 1011 giving 4.55% abv - recipe 5%

All went well ish - Don’t know if I should be pleased or disappointed with my efforts???

[bitter_dave]

All went well ish - Don’t know if I should be pleased or disappointed with my efforts???

You should be pleased I wish my first AG had gone that according to plan. Go and have a beer immediately if you're not already

[Frothy]

most excellent - well done

Matt

[Andy]

Sounds like an excellent first brew, well done.

[Doingatun]

Thanks for the coments lads - Got a Coopers Austrailian Lager Kit in a corny chilling - think I'll go and pull a pint if I've passed part 1

[mysterio]

Beersmith says your efficiency is at 74% but different programs use different calculations (i.e. what the extraction potential of malt is).

Well done anyway that's great efficiency, use it when you calculate your next recipe.

[Doingatun]

Enjoyed the day …I could not have managed without the help, advise and the knowledge gained from this forum – Thanks

The books I’ve got are good but for me throw up more questions than they answer.