Hi guys, very new to this forum and quite new to all-grain brewing as well so I have a question regarding my mash tun.
Currently I am using a plastic bucket, which works fine but I lose temperature very rapidly and therefor I am going to invest in a cooler box, however where I live (The Netherlands) there’s not a wide arrangement of cooler boxes.
I found two on the european Amazon and was wondering if you guys could give me some advice on what to get:
As you can see there’s not a lot of price differences and the only real differences is the volume (30 vs 40 liters)
I usually make 2.5 gallon batches but I want to start 5 gallon batches since I have the necessary equipment.
I guess what I am asking from you is a general idea if this would be a good cooler box to get for mashing and if a 30 liter is fine for 5 gallon batches (even though it is a small differences in price, I am a student so try to save money wherever I can)
When I started all grain brewing, I did BIAB in a large steel pot, and during the mash simply wrapped it in an old sleeping bag. I would only get 2-3c drop in temp over a 60min mash.
Using 1.5 qts/lb as your water to grain ratio and assuming that your maximum grain weight is 18 lbs.
1.5 qts/lb * 18 lb = 27 qts or 6.75 gal of strike water
Grain displacement = 15 lb * ~0.32 qts/lb = 4.8 qts or 1.2 gal
As you can see, this scenario would absolutely max out the 30 L cooler and make it hard to stir. Your maximum gravity using 18 lb and a 75% efficiency would be:
37 ppg * 75% efficiency = ~29 ppg
(29 ppg * 18 lb)/5 gal = 1.103 S.G.
If you crunch the same numbers with the 40 L cooler and an increased grain maximum you get:
Using 1.5 qts/lb as your water to grain ratio and assuming that your maximum grain weight is 20 lbs.
1.5 qts/lb * 20 lb = 30 qts or 7.5 gal of strike water
Grain displacement = 20 lb * ~0.32 qts/lb = 6.4 qts or 1.6 gal
Your maximum gravity using 20 lb and a 75% efficiency would be:
37 ppg * 75% efficiency = ~29 ppg
(29 ppg * 20 lb)/5 gal = 1.160 S.G.
If you do not plan on making humongous beers or you plan on brewing < 5 gal, you can most certainly use the 7.9 gal cooler. If you mash in stiffer than the 1.5 qts/lb I used you will have plenty of room to make 5 gallon batches of humongous beer.
If you consistently brew big beers or are going to be consistently making 5 gal batches then the larger cooler may be a better idea as it grants you a bit more leeway to change the water togrist ratio or increase the size of the grain bill.