BrewingTechniques
Q-&-A with the Troubleshooter
Dave Miller takes on...
  • Head Retention Problems
  • How to Treat Brewing Water
  • Turning a Fridge into a Walk-in Cooler
  • Foiling Beer Infections
  • Fermenting in a Hot Climate
  • Stubborn Cider Fermentation

    Republished from BrewingTechniques' October/November 1997.

    Head Retention Problems

    Q: I make my usual Scottish mild from a 1.6-kilogram can of lightly hopped malt extract syrup mixed with 3/4 kilogram of dark dry malt and just less than 1 kilogram of corn sugar. I prime with 1 1/4 cups of corn sugar per 5-gallon batch before bottling. The original gravity is about 1.044 and ends at about 1.013.

    I have no problem with carbonation (I even get good small-bubble formation), but I am experiencing serious frustration creating and maintaining the head. Can you go over the main factors in head retention? My serving glasses are clean of all soaps, and I store the beer in a cool environment. Adding heading powders before bottling has not worked for me either.

    I sometimes use a teaspoon of rehydrated Irish moss in the 30-minute hard boil. Is this pulling out some of the good head-creating proteins along with the bad high molecular weight haze-forming proteins?

    Someone told me that using bleach to sanitize (even if triple rinsed) is the head killing culprit. If so, how?

    I would also like to know how to keep using bleach (yes, I know about chlorine dioxide products) while avoiding the formation of trihalomethanes and chloro-phenols described in "Applications of Chlorine Dioxide: A Postrinse Sanitizer that Won't Leave a Bad Taste in Your Mouth" (BrewingTechniques 5 [2], pp. 76-81 [March/April 1997]). What are these compounds? Are they hazardous to me or my beer? If so, how? What precautions should I take to minimize or eliminate them?

    A: If you are thoroughly rinsing your fermentors and other equipment, then chlorine is not the source of your foam retention problem. The problem is simply that you are making a very light extract beer; it may not have a low gravity, but a significant proportion of its fermentable material is corn sugar. The beer is low in protein and other foam-retaining compounds.

    Try eliminating Irish moss for a start. In my experience, it is not necessary to achieve clarity in extract beers. The next step would be to go to an all-malt recipe. The more malt you use, the more foam retention you will get.

    I am surprised that your foam-retaining powders have not helped. Propylene alginate (I assume this is what you used) always worked for me. Check your beer's pH to make sure it is not abnormally low or high. Finished ales should be in the range of 4.0-4.5.

    Trihalomethanes and chlorophenols are worth avoiding. Chlorophenols impart a nasty medicinal taste. Some trihalomethanes are carcinogenic. Bleach is an effective sanitizer, but if it contacts beer these nasties are inevitable. If you use bleach, limit contact time with the vessel (to avoid corrosion), use the proper strength (two tablespoons per gallon -- more is not better), and rinse it off thoroughly before racking wort or beer into it.

    Incidentally, why insist on staying with bleach? Compared with the cost of malt and hops, sanitizers don't even register on the brewing budget.

    How to Treat Brewing Water

    Q: To brew light ales, particularly Koelsch styles, using my local water I need to preboil the dechlorinated water to precipitate the carbonate-bicarbonate ions. My water contains the following :

    
    Ion	mg/L
    Ca	46.0
    Mg	 3.0
    Na	35.0
    SO4     36.0 
    Cl	49.0 
    Total hardness/CaCO3	128.0 
    pH	7.7 
    Total alkalinity (CaCO3) 107.0 
    Bicarbonate 131.0 
    Carbonate 0
    
    I plan to boil 5 gallons of water with 1 1/2 teaspoons of gypsum or calcium chloride, but I need help with some of the details of the procedure.

    To thoroughly aerate the water after boiling I plan to pour it back and forth between the brew pot and the mash tun half a dozen times. Should I aerate upon bringing the water to a boil, or wait until the temperature drops to 180° F (82° C) or less?

    How long after aeration should I let the water rest before I rack off the precipitate? Should the water cool to a certain temperature? Could it be left to rest overnight and cool to room temperature, or is it better to keep the rest brief and aerate it while still hot? Finally, when is the precipitate more likely to be reabsorbed?

    A: You are right: your water needs to be treated to make it suitable for brewing Koelsch or Pilsner or other blond beers. The alkalinity is too high.

    To get maximum precipitation, you need to aerate the water while it is boiling. I know this is a tough trick, but because oxygen is almost totally insoluble in hot water, simply aerating the water before boiling will not give the best results. Much of the oxygen will gas out before it can react with the bicarbonate.

    The best way to aerate hot water is to set up a recirculating system that pumps water out of the kettle and returns it through a spray nozzle. With this arrangement, the water does not even need to boil: a sustained temperature of 190° F (88° C) is sufficient.

    If you do not have a pump, the next best thing would be to aerate the water during the boil with some kind of agitator such as a drill-mounted paint stirrer or wire whisk.

    If all this sounds like too much trouble, you might consider neutralizing your water with phosphoric acid. This is much simpler and of course demands little of your energy or time.

    If you decide to boil your brewing water, please reconsider your plan for pouring hot water back and forth between two vessels. You may get away with this for a while, but sooner or later you'll slip and then there will be hell to pay. Also your plastic surgeon. Unless you enjoy watching daytime TV and sweating bullets while you wait out the time between morphine doses, consider another way to aerate boiling water.

    You should allow the water to rest undisturbed for at least an hour before racking it off the precipitate. Longer will not hurt. Very little chalk will redissolve into the water. The big danger is stirring up the water while you decant it, thereby carrying some of the chalk into your mash tun or sparge liquor container.

    Turning a Fridge into a Walk-in Cooler

    Q: I have a chest-type freezer that works well for lagering. It gives me little space, however, for lagering and controlled fermentation year round. Can I turn a currently serviceable refrigerator/freezer into a small "walk in" cooler? The idea seems feasible provided the cooler is properly insulated, but I'm not a refrigeration technician and wonder if I'm asking a fridge to do too much.

    Here's the plan: I would remove both the refrigerator and freezer doors and construct an add-on box to fit the door openings. Styrofoam insulation between the studs and on the interior will provide the insulation. I would like to ferment lagers at about 50° F (10° C) and ales at about 65° F (18° C). My basement is about 58° F (14° C) in the winter and about 72° F (22° C) in the summer.

    Is this feasible? How many cubic feet should the "cool box" occupy at the maximum?

    A: Several home brewers I have talked with have successfully doubled the size of their refrigerators by removing the doors and building on a homemade insulated box. Because the fridge is not opened frequently, the compressor can keep the larger space cold without working too hard. A few pointers:

  • Make sure to use waterproof materials. Styrofoam is the best choice for insulation.
  • Get a really good tight seal around the door. The seal makes more difference than the "R" value of the insulation.
  • Make sure all the inside surfaces of your add-on box are cleanable.
  • Use an auxiliary thermostat with a range of 30-70° F (-1 to 21° C). Most refrigerator thermostats will not hold a temperature higher than 45° F (7° C), which is a little too low.

    Foiling Beer Infections

    Q: What kind of infections can occur in beer, and when? From the reading I've done my understanding of sanitization is as follows: Sanitization is not as critical during the "hot side" of brewing (mashing and boiling), because the temperatures and duration of the boil will kill any nasties. The most likely opportunity for infections to occur is after the wort has cooled and before the yeast population grows and the pH of the wort lowers. After fermentation begins, the environment is too hostile for most infections to flourish.

    Using this logic, I spend most of my time cleaning my counterflow chiller, connecting hoses, and carboy. Yeast preparation is also critical. I grow my starters in a growler, usually three days in advance. I taste the starter before pitching to ensure that I don't pitch an infected starter.

    According to my hypothesis, the transfer from primary to secondary and dry-hopping in the secondary should be a "lower risk" opportunity for infection. I assume the same to be true of bottling and/or kegging. This is not to say that I don't clean everything, but rather that I tend to be less stringent about cleaning equipment to be used after fermentation is complete compared with those items that contact cooled wort.

    Despite my efforts I still get occasional bad batches (more often in the summer months). When infections occur, they usually show up right after primary fermentation, hence the logic in my cleaning procedure. I try to sample the brew at each interval to pinpoint the flaw in my process, but the problem persists.

    Are certain kinds of infections prone to happen at different times (for example, during the boil, cooling, fermenting, and so forth)? How would I identify the time of infection? Also, after a soured batch is discovered (and dumped), should any extra effort be made to clean the carboy, keg, and any other equipment that contained that batch? Can bacteria survive in a carboy after scrubbing it with a brush and B-Brite followed with a rinse of bleach?

    A: Your brewing theory is only half right. It is correct that boiling sterilizes the wort, so you need not be as concerned with the sanitization of your mash tun, kettle, and so forth as with vessels, hoses, and fittings used later. Once the wort is cool, however, you need to be as careful as you can, and certainly don't let your guard down with fermented beer. Even breweries that pasteurize their beer in the bottle go to great lengths to keep their bottling equipment as clean and sanitary as possible.

    If your infections show up at the end of primary fermentation, the contamination is coming either from your yeast starter or from some piece of brewing equipment that touches the cooled wort. You should critically evaluate your cleaning procedures in each of these areas.

    You need to take every precaution with your yeast starters, including flaming the mouth of the jug before pitching into your carboy. If anything, you have to be more careful with starters than with the actual batch of beer, because bacteria or wild yeast in the starter will multiply right along with the brewer's yeast.

    Bacteria can survive in a carboy if the cleaning procedure leaves any deposits of film. You can check for film after cleaning by first rinsing your carboy and letting it cool, then adding a little hot water, which will cause condensation on the inside of the vessel. Examine the condensation. If you see a pattern corresponding to the brush strokes, there is still a film inside. This film will provide a haven for bacteria. Remember, a sanitizer must come into actual physical contact with a microbe to kill it.

    Carboys that have produced an infected batch of beer require extra cleaning. Many cleaning brushes have bristles that are too stiff to effectively clean carboys. The surface has to be wiped, not scratched. Try a softer brush or try manufacturing a carboy cleaner with a sponge rather than a bristle brush. If I had this problem, I would soak the carboy overnight in a solution of PBW (a noncaustic cleaner from Five Star Affiliates, Commerce City, Colorado) at a rate of 1 oz/gallon after my initial cleaning. Start the soak with hot PBW (Five Star recommends a temperature range of 120-140° F [49-60° C] for glass or plastic fermentors and a range of 140-160° F [60-71° C] for stainless steel brewhouse cleaning) and let it cool overnight. Next day, scrub it again, then follow with a thorough rinsing, then an acid rinse followed by another water rinse. Immediately before use, I would sanitize it with an activated chlorine dioxide solution, which I would drain well but not rinse.

    I suggest the same procedure for your wort chiller, but you should backflush the coil with hot PBW solution using a pump for 30 minutes, then leave it packed with the solution overnight. Follow up with a thorough water rinse, then acid rinse and water rinse the next day. Pack the coil with iodophor or chlorine dioxide and leave it full until the next brew day. Flush out the coil with water immediately before use. Don't forget about valves, transfer hoses, and other fittings. These need to be included in the circulation loop with your coil.

    It is difficult to correlate an infection with its source. Any microbe that can grow in beer can get into the system at any point from cooling onward. You would have to plate out samples from each stage to see where the bacteria or wild yeast got started. The best approach for home brewers is to assume everything is contaminated, and act accordingly.

    Fermenting in a Hot Climate

    Q: I recently moved to Texas from Seattle. In Seattle I had a basement that stayed a steady 50° F (10° C) pretty much all the time. Now I have no basement and must contend with fermenting at 78° F (26° C). I manage to cool my carboy down by about 5° F (3° C) by placing it in a shallow water bath and dressing it in an old T-shirt. Do you have any tips or hints for brewing in warm weather? I used to use Wyeast Labs' London ESB yeast for my ESB. Is there a better choice for warmer fermentations?

    A: Wyeast's London ESB yeast is, in my experience, the best choice for British bitters. I don't know how it responds to warm fermentations. Have you tried it? If it gives too many esters, then Wyeast #1056 (dubbed American Ale) might work better; as I said in a previous column ("Fermenting Ale Yeast Cool," BrewingTechniques 5 [4], pp. 34-35 [September 1997]), it does not seem to be much affected by temperature, though I've never run it quite as high as you're proposing.

    Long term, I think you will need to invest in a refrigerator for brewing. Texas is a great, but hot, place.

    Stubborn Cider Fermentation

    Q: I've been home brewing beer successfully for several years now, but I tried my hand at making my first batch of hard cider a few days ago with really rotten results. I am hoping you can help me diagnose the problem. The recipe below was taken from a magazine article, with a few minor modifications.

    Recipe
    14  12oz cans of frozen apple juice concentrate
    2.5 lb clover honey
    12 oz safflower honey
    1 T ground cinnamon
    2.5 tsp acid blend (acid content of the must after adjustment was 0.55)
    5 tsp yeast energizer
    1.5 tsp potassium metabisulfite (to sterilize the must)
    2 pkg 	dry wine yeast (Cote des Blancs)
    Tap water to make 5.5 gallons
    Original gravity: 1.065, adjusted to 60° F (16° C).
    

    My procedure was as follows. First, I boiled the honey in about 1 gallon of water for about a half an hour, skimming the top layer as it arose. I then chilled the honey water, added it to the apple juice concentrate in my carboy, and topped off the carboy with tap water to make 5.5 gallons. I then measured and adjusted the acid level to my liking, after which I added the cinnamon. At this point the must tasted wonderful.

    Next I added the potassium metabi-sulfite to the must and let it sit under a fermentation lock for 24 hours. The next day I aerated the must well with my aquarium pump. I then rehydrated and pitched the yeast, added yeast nutrients, reattached the fermentation lock, and smiled with contented anticipation.

    When I checked in on my tasty concoction 24 hours later, however, I saw no signs of fermentation. My first reaction was that the yeast may have been bad. I promptly went down to my favorite homebrew store and purchased two additional foil packages of Munton & Fison ale yeast. I've never had a bad batch of beer when using Munton & Fison yeast, so I was hopeful of saving my cider at this point. When I got home I added an additional 1.5 tsp of potassium metabisulfite to the must in case any wild bugs got into it, and I let it sit under a fermentation lock for another 24 hours. The next day I aerated the must again, added more yeast nutrients, rehydrated and pitched the ale yeast, and attached the fermentation lock.

    The morning after pitching the ale yeast -- still nothing. Nor did I see any sign of fermentation when I came home later that evening, nor the day after. The whole batch was a loss. I did notice something interesting, however: sitting on the bottom of my carboy was what looked like a half inch of yeast sediment. It appeared to me that maybe the yeast initially grew in the presence of the oxygen and yeast nutrients, but somehow was unable to ferment the sugars in the must. Is this possible?

    I checked the fruit juice concentrate to see if it contained any preservatives that could have killed yeast. There were none. Is it possible that the vitamin C in the concentrate could have inhibited fermentation? Were the sugars in the fruit juice too complex to ferment? I also wondered about my having used tap water instead of bottled water. I usually use bottled water when making beer because my local water is rather hard and I believe it has reduced my all-grain extract efficiency on some occasions, though it has always served well enough for extract brewing.

    Another possibility is that I somehow sulfited the must improperly. Should I not have used a fermentation lock at this point? I had assumed that my vigorous aeration would have "scrubbed" away any harmful gasses produced in the sulfiting process.

    A: Two culprits are likely here: sulfur dioxide (SO2), which is the bacterial inhibitor/antioxidant produced by your sulfite, and additives in your must ingredients. Sugar is not an issue. Fruit sugar is mainly fructose, a simple sugar, and honey is mainly invert sugar. Yeast has no trouble with either one. I tend to agree with you that a vigorous aeration should scrub out the SO2, so that seems the least likely explanation. Still, it's hard to be sure. Next time you try cidermaking omit the sulfiting and pitch your yeast right after aeration.

    You mention the lack of additives in the juice. But the can says "apple juice from concentrate." What was in the concentrate? I don't know that much about labeling laws, so I don't know whether the manufacturer could have spiked the concentrate without reporting as much on the label of the finished product. Also consider your honey. I once tried to make a batch of mead using grocery-store clover honey, and I could not get it to ferment. The label said nothing, but I am convinced it contained some antifungal additive(s).

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