how much sparge water is to much?

[insco2]

i'm just throwing this one out there for you guys. I typically brew 10 gallon batches and im tring to figure out what a good mash volume vs. sparge volume is. I mash in a 30 quart cooler with about 4.5 gallons and then sparge the rest to make the final amount after boil about 11 gallons (when i roll the boil, i evaporate 1gl/30mins).so in other words i sparge with 6.5 gallons. Is there a certain number or event im looking for? I do iodine test and they turn up no color change which i belive means the starch is converted, but is this enough? I really enjoy all-grain i just need to figure out the steps and checks that need to be applied to very batch. thanks guys.

[Danno]

Well, the sparge doesn't have anything to do with starch conversion other than that you should have converted all the starch before you start sparging.

The amount of water you need will depend on many factors so no one can give you a number with any certainty. Your mash tun design, how fine you grind, how much you stir during the mash (if at all), your sparge rate, your water chemistry, and your run-off rate all are part of the equation.

From a pratical point of view, you can sparge until the pH rises above 6.0 where tannins start to release. Interestingly enough, this happens when the gravity of the run-off drops to about 1.010 so you can also use your hydrometer to determine the stop point. If you pre-acidify your sparge water, there isn't an official stopping point however you run into diminishing returns as your're adding lots of water with small quantities of sugars in them which will drop the OG of your collected wort. Now that can be corrected for by boiling longer.

These days, I don't even bother with hop calculations until I've collected my wort and calculated how long I want to boil to hit a specific OG. I check it again before I add flavor hops so that I'm real close at flame out. Remember that bittering hops don't change their utilization after 45 minutes in the boil so you can boil an extra hour if you want before adding flavor hops.

[insco2]

danno that makes some sense, i guess numbers is what i was looking for 1.010 on the gravity and 6 on the ph meter will help. that is a start and i will be paying attention to those on the next brew day. you also mentioned pre-acidify the water, can you get a little more specfic on that subject? my last batch was .07 points lower than the recipe called for, I know it would be opening a can of worms to ask about that but slowly i am figuring this problem out on my own. I guess i was wondering about the sparge being a reason the gravity was so low.Maybe on the other hand im making this into a bigger problem then it real is, I will have good beer to drink in the final hour.

[Danno]

also mentioned pre-acidify the water, can you get a little more specfic on that subject?

The enzymes in the mash work best between 5.2 and 5.4 pH. Tannins are realeased when the pH goes above 6.0 pH. If you use something like phosphoric acid to acidify your sparge water to 5.2 to 5.4, you wont have to watch your mash or run-off pH.

my last batch was .07 points lower than the recipe called for

While improper pH or stopping the sparge early can lower your efficiency, that's not as important as being cnsistent and then using your efficiency % to determine your malt bill. BYW, the most common reason for poor efficiency is the crush of the malt, not pH or sparge.


If I were in your shoes rght now, I would get to know your water chemistry before anything else. That will tell you how you need to adjust your process for the item that you have the least control over. Most of what you have asked doesn't need much attention unless your water is messed up.

[insco2]

hey danno how close is portland to your hometown? My wife has a job offer out in portland and i love the area (pacific nortwest that is) and im encouraging her to take it. plenty of micro-brew outfits in the area,and not so rainy,seeing that seattle just broke a 27 day rain streak!!!

[Danno]

how close is portland to your hometown?

I am about 10 miles south of Portland at the south end of the metro area. We do boast about our 75 days each year where we enjoy sunshine.

As far as I can see, rain is the only reason not to live here. Portland has all of the advantages of a big city but yet it only takes 30 minutes to cross the metro area in any direction except during rush hour. But then we have a true rush hour. Crowded on the freewys from 7am to 8 am and from 5:00 pm to 6:00 with very few exceptions.

[George]

I'm assuming you're fly sparging, right? Like Danno says, you should stop the runnings before they drop below about 1.010. If you only have a hydrometer, measuring the runnings can be a pain because you have to temperature compensate them. I haven't tried this myself (because I batch sparge) but Dan Listermann has pointed out in the past that a hydrometer reading of 1.000 at sparge temperatures is 1.010 when you correct it for temp. So all you have to do is sparge until your direct hydro sample (no correcting) reads 1.000. Neat, huh?

Well, I suppose that's not quite right. 1.000 (uncorrected) isn't your goal; it's your limit. So sparge until you get 11 gallons in the kettle, but stop if your runnings drop below the magic number and add water to the kettle to make your 11 gallons so you'll have enough to boil off.

As for your last beer being 7 points low, that's not necessarily related to sparge volume. Did you calculate efficiency, btw? If your efficiency is continually low, one way to isolate the cause is to switch to a batch sparge for one brew. Batch sparge will remove all the efficiency variables related to the sparge setup and mashtun design. Many people see efficiency rise when they switch to batch sparging. If that's the case, you either stick with batch sparging or you make some changes to your mashtun design.

One final question about your sparge technique: When you are done sparging, is the MLT full of water or drained? I mean, after you're done sparging into the kettle, could you still open the valve and get another gallon of water from the tun without putting water on top?

[Danno]

Well, it's not unusual to find Dan L. off by a bit (if he was quoted correctly) but most of his advice is sound. You can actually run to about 0.990 if you don't wait for the temperature of the hydrometer sample to cool. Correcting a 0.990 reading at 140°F yields a reading in the 1.010 range (I don't have my Promash program handy for the exact adjustment). These days refractometers are so cheap, I usually don't bring up temp corrections because you never know whether a person is using that or a hydrometer.

If Insco2 loses one gallon every 30 minutes then he should sparge to at least 12 gallons to hit a final of ten.

I'll also take issue with batch sparging being more efficient than fly sparging. The big promoter of batch sparging is Denny Conn, a personal friend, and he will admit that he gets excellent efficiencies but does not promote that it results in better efficiency (unless he's changed his tune lately). Batch sparging is a great way to go if you want to simplify things and I have tried it a few times hoping to save some time but I don't see any real time savings. It is a lot easier if you do not have a system setup to fly sparge by gravity or pump and Denny's low buck system is a big reason why he does it.

Again, the easiest and most effective way to change efficiency is the crush of the grain, not going to batch sparging or changing the way you fly sparge. If you don't have a mill that you can adjust, then just add more malt. For years, I suffered from my LHBS's nonadjustable mill that results in a 55% efficiency. I kept thinking it was me. When I bought my own mill, my efficiencies jumped to 75%+.

Again, getting an 80% efficiency isn't as important as having a consistent efficiency.