Sparging

[Niall K]

With my first all grain tomorrow, I'm just reading up on a few things to make sure everything goes to plan. When the mash is completed, I know you collect about 2 liters or so of wort and return it to the mash tun until you get a clear runoff. Do you then run off all wort in the mash tun to completely empty the wort from the mash tun before adding the sparge water? Also when sparging should the sparge water be above the grain bed so that the grains are always submerged? I think I remember reading that the grains should be under about 2" of sparge water.

Thanks
Niall

[bitter_dave]

I generally run off the mash tun until the the liquid is just below the grain bed, then start sparging, maintaining the level of liquid at the level of the grain bed. Some people drain the mash tun completely, though, then start sparging; it's all down to personal preference, I find the way I do it easiest. Also, some people maintain a couple of inches of sparge water above the grain, but it is not neccessary and may reduce efficiency a bit, but then I'm sure there are people who would disagree.

Ultimately there is no one right way to mash beers, and it is pretty difficult to make a complete hash of it, so just enjoy yourself

[Niall K]

Thanks for the replies. Its a lot clearer now

[Niall K]

Just have my mash under way. Hit my target of 65C. What temp should I heat the sparge water to?

[Jim]

Just have my mash under way. Hit my target of 65C. What temp should I heat the sparge water to?

Anything between about 75 and 80C should be fine. The temperature will drop on its way to the grain bed, so you should achieve 70 ish minimum.

[Niall K]

I have added 10.5 liters to my mash. I doing a 19 liter brew. Can I assume that I will lose 3 liters in the end of the mash tun and in the grains. So that should give me a 7.5 liter collection. Assuming I am going to lose 30% over the boil volume, would I be right in saying that I need another 17.2 liters before boil?

19liters +30% =24.7 liters (-7.5 from collection) = 17.2liters

Thanks
Niall

[mysterio]

I think it's best to adopt a more cavalier attitude when knocking out your first brew and then take steps to improve your techniques and accuracy it over the following brews. Like I said I never worked on the numbers but over time I found it all came together.

I agree whole heartedly here... don't get bogged down in calculations because whatever you calculate will inevitably go out the window when you actually do it. I sparge until I start to get near to my brew-length then maybe have a sip of the wort or take a reading. If it's still sweet i'll let it keep sparging, if it's starting to taste watery i'll take a reading and stop it between maybe 1.013 - 1.010 (adjusted for temperature) or thereabouts. Then i've got a visual reference on my brew pot of how much evaporation i'll lose in 90 minutes, so i'll top up with water to this point before the boil and top up at the end to adjust to my target gravity.

Also as mentioned you'll probably find you'll lose some temperature between the sparge water and the grain bed. I'd say start with maybe 80C sparge water, measure the temperature of your grain bed and try and target around 70-77C.

[SteveD]

If you're using a spinning sparge arm, and a coolbox mash tun you'll need the sparge liquor to be at 90c+ to maintain the mash bed between 74c and 77c. 80c sparge liquor will give you a mash bed of about 60c. Trust me.

If you're using other gear, then trial and error. Stick a thermometer in the mash bed and see what you get, adjusting the sparge liquor temp accordingly.

[AT]

That's handy to know i was sparging at 77c, so it's probably better to just biol it then?

[mysterio]

If you're using a spinning sparge arm, and a coolbox mash tun you'll need the sparge liquor to be at 90c+ to maintain the mash bed between 74c and 77c. 80c sparge liquor will give you a mash bed of about 60c. Trust me.

True, I recently discovered this and my efficiency went up a couple of percentage points. If you batched sparged with 90C you may well get tannins in the beer though so I suggested 80C just in case!

[SteveD]

If you're using a spinning sparge arm, and a coolbox mash tun you'll need the sparge liquor to be at 90c+ to maintain the mash bed between 74c and 77c. 80c sparge liquor will give you a mash bed of about 60c. Trust me.

True, I recently discovered this and my efficiency went up a couple of percentage points. If you batched sparged with 90C you may well get tannins in the beer though so I suggested 80C just in case!

I'm not sure if you will as the ph in the grains will be lower and as I understand it, it is a combination of a higher ph and temperature that leads to tannin extraction. Batch spargers become all smug when you mention tannins as they don't experience the rising ph in the mash tun that fly spargers get.

I'm a smug hybrid batch/fly sparger because I don't get rising PH either, no matter how much sparge liquor I use. Why? My mash liquor PH is usually around 6, giving about ph 5.2 in the mash with a pale ale or bitter grist. During the mash, I then adjust the remaining liquor to ph5.5 with lactic acid and this will be used to sparge and if necessary top up. So, during the sparge, there is no way on earth the ph is going to rise to the point of tanninn/phenol extraction.

One easy step, and it removes the danger. What makes it easy is preparing all the liquor I need for the brew in one go, and just making the one adjustment to all the remaining liquor once the mash is underway.

[monk]

I'm not sure if you will as the ph in the grains will be lower and as I understand it, it is a combination of a higher ph and temperature that leads to tannin extraction. Batch spargers become all smug when you mention tannins as they don't experience the rising ph in the mash tun that fly spargers get.

I'm in a perfect position to test this for you. I batch sparged my IPA last month with boiling or near-boiling water--I had read somewhere that you should, in order to get the grain bed temp up enough. I'm not so sure about the technique now, but in about 2 weeks I'll be drinking the finished beer and can tell you if there's any tannin flavor.

monk[/i]

[SteveD]

I'm not sure if you will as the ph in the grains will be lower and as I understand it, it is a combination of a higher ph and temperature that leads to tannin extraction. Batch spargers become all smug when you mention tannins as they don't experience the rising ph in the mash tun that fly spargers get.

I'm in a perfect position to test this for you. I batch sparged my IPA last month with boiling or near-boiling water--I had read somewhere that you should, in order to get the grain bed temp up enough. I'm not so sure about the technique now, but in about 2 weeks I'll be drinking the finished beer and can tell you if there's any tannin flavor.

monk[/i]

To avoid any confusion..it's not a particular sparge liquor temp that is critical - it's the mash bed temp. That is what you should monitor, and adjust the sparge liquor temp to give you a mash that is near to but not exceeding about 77c. What I and one or two others have observed is that with a spinny sparger, the sparge liquor temp needs to be in the 90's to achieve 77c in the mash bed - probably because of heat loss through the sparger and fine spray.

On the other hand if you're batch sparging (re-mashing) by dumping a load of hot liquor in at once and stirring, 90c+ might well be too hot. You need to monitor the mash bed with reference to your particular technique and equipment, and fine tune your sparge liquor temp to give you the right mash bed temperature in your own setup.

Disclaimer:- it's not my fault if you all cook your grains by ignoring this fact!