The Great Beer Debates
There’s nothing like having a beer with a fellow homebrewer. Nothing, that is, except for having a beer with a fellow homebrewer and telling him that his brewing practices are all wrong. Homebrewers love a good argument, and there’s no shortage of good arguments within the hobby. If it’s possible to do something more than one way, there will be homebrewers in each camp who adamantly insist that their way is the right way. In this article, I’ll review three homebrew controversies and try to sort fact from fiction.
Yeast Starters
If you pick up a copy of BYO ten years from now, there might be articles about brewing with nanobots or stories about which gene sequences to insert into your brewing yeast. There might also be an article on whether to pitch your entire yeast starter or whether to collect the yeast sediment and pitch only that. The “whole starter” versus “yeast sediment” controversy has been around a long time and probably won’t go away soon.
Pitch the Whole Thing!
Homebrewers who advocate pitching the whole starter claim that pitching the whole starter ensures that yeast health is maximized. If the starter is pitched at high kraeusen, the yeast are actively fermenting. They have taken in oxygen, built up their cell walls, and are actively taking in sugar and producing alcohol and CO2. Yeast in this condition can “hit the wort running.” The time between pitching and when active fermentation is visible (the lag time) is minimized. So the opportunity for a wild yeast or bacterial infection to take hold is minimized, too.
Whole starter advocates claim that yeast in the sediment is not as healthy as actively fermenting yeast. Yeast sediment is formed by yeast that have stopped fermenting and dropped out of solution, or yeast that have dropped out of solution when the starter is crash cooled. In either case, this yeast will need to recover before it can start fermenting. And while it is recovering, other microorganisms can be growing within the wort.
Pitch the Sediment!
Homebrewers who advocate pitching only the yeast sediment see things differently. By pitching the whole starter, you are also pitching the metabolic byproducts produced by the yeast during the growth phase. In particular, pitching the whole starter means adding diacetyl to your wort.
Diacetyl is a molecule that forms early in fermentation, when oxygen is still present in the wort. The precursor of diacetyl, alpha-acetolactic acid, is formed by yeast metabolism. Yeast excrete alpha-acetolactic acid into the wort, where it can react with oxygen and form diacetyl. Diacetyl lends a buttery taste and smell to beer. Although diacetyl is desired in some beers, most brewers strive to get rid of it. Most beer drinkers perceive beer without perceptible diacetyl to be “cleaner” than beer containing diacetyl.
Yeast absorb diacetyl later in fermentation. A good clean yeast will absorb diacetyl until it is at a concentration below its taste threshold. Wyeast 1056, reputedly the same yeast Sierra Nevada uses and a favorite among homebrewers, is a good diacetyl reducer. Other yeasts, especially some British ale yeasts, tend not to reabsorb all the diacetyl they produce.
By pitching only the sediment, you pitch the yeast but leave behind their wastes produced in the growth phase. This is the heart of the “sediment only” position. But, there are other practical reasons to pitch only the yeast sediment. If you pitch the whole starter, you will need to make the starter similar in color and gravity as your beer. This isn’t always practical. When making a barleywine, for example, most brewers make a starter of average gravity and pitch only the yeast. Pitching the whole starter would dilute the barleywine wort.
Both Sides Respond
Advocates of sediment pitching insist that the criticisms of sediment pitching aren’t compelling. While lag time is increased when only the yeast is pitched, infection is not a problem if you clean and sanitize your equipment well. In addition, yeast are hardy and will bounce back quickly when given a nice home in a well-aerated wort.
The “whole starter” folks likewise don’t buy the sediment-only critiques. A clean yeast strain will eventually take up the diacetyl it produces. Likewise, other metabolic byproducts get absorbed or are blown off during fermentation. In addition, it only takes a little planning to ensure that your yeast starter’s gravity and color is compatible with your wort.
Resolution?
So who’s right? Well, as is the case with many long-standing controversies, neither side is right or wrong. Whole starter advocates see a starter at high kraeusen as a population of maximally healthy yeast. Sediment pitchers see a population of yeast swimming in their own wastes. Conversely, whole starter advocates see sediment as a pile of sickly yeast, while sediment pitchers see it as a blanket of dormant cells.
The point that often gets lost in the whole debate is that you can brew good beer using either method. When choosing between the methods, you simply have to determine what factors are the most important to you. Do you worry about infection? Do you get nervous during the time between pitching and the first signs of fermentation? If so, you will probably prefer pitching the whole starter. When pitching the whole starter, make your starter as similar to your wort as you can. And pick a clean yeast strain, unless you want diacetyl and other fermentation byproducts in your finished beer. Finally, plan to leave room in your fermenter to hold the entire volume of wort plus your starter.
Do you worry about your beer being as clean as it can be? Would you prefer to not bother matching your starter to your wort? If so, and you are comfortable with a few extra hours of lag time, you should consider pitching the yeast sediment only. If you pitch the yeast sediment only, either crash cool an active starter or use yeast that has just settled. Don’t use yeast sediment that has been sitting around for more than a couple days. If possible, separate out and pitch only the white middle layer of the yeast sediment. This layer is made up of the healthiest yeast. If you can’t separate the layers, don’t worry. Also, be sure to clean and sanitize your fermenter thoroughly. Don’t give bacteria or wild yeast a chance to get a foothold during the lag time. Finally, aerate your wort thoroughly. Your yeast will need to recuperate somewhat, and they’ll need plenty of oxygen to do so.
Hot Side Aeration
My first homebrewing book was “The Complete Joy of Home-brewing” by Charlie Papazian. So for years I would pour my hot wort through a strainer into my fermenter (as the book called for) to separate the hops and trub from the wort. These days, I do things differently. I take care to avoid disturbing hot wort. For example, I now cool my wort before separating it from the hops and trub. I don’t splash hot wort or do anything that might introduce oxygen into my beer-to-be when it is hot. Why the change? To avoid hot side aeration.
Hot side aeration is the introduction of air into mash or wort, on the “hot side” of brewing. The “hot side” of brewing begins when hot water and grains are mixed together in the mash. It extends through the boil and up the point when the wort is cooled. George Fix, the author of several homebrew books and the man most responsible for bringing concerns of HSA to the homebrewing public, suggests that 86° F (30° C) is the transition point between the hot side and the cold side of brewing.
Avoid HSA!
Hot side aeration supposedly results in staling compounds that eventually develop in finished beer. Brewers who feel that HSA should be avoided attempt to minimize any oxygen introduction on the hot side. Specifically, they avoid mash abuse and any agitation of hot wort. Mash abuse includes excessive stirring of the mash, rough transfer of the mash from the mash tun to the lauter tun, and any sparging technique that involved excessive splashing of the wort. HSA avoiders likewise treat their wort gently. Many minimize the number of times they stir the wort. At a minimum, these brewers stir gently enough not to raise any bubbles or foam. Straining hot wort is, of course, out of the question.
There will always be some splashing or agitating of wort during brewing. Most brewers who try to minimize HSA simply try to treat their beer as gently as possible on the hot side.
Don’t Sweat It!
Although many homebrewers altered their brewing practices when information about hot side aeration first emerged, there is a growing skepticism that the dangers of HSA are overstated.
Critics of HSA have two main points. First, the experiments demonstrating the problems associated with HSA also show that the size of the effect is not that great. Unless you are seriously abusing your mash and wort, the negative effects of HSA may be so slight as to be undetectable. Second, many homebrewers’ beers are consumed before the symptoms of hot side aeration would develop. Even if the dangers of HSA are real, they may not develop in time to be a problem for your average homebrewer.
Resolution?
Should you worry about HSA or not? Opinions differ, and much of the argument is very technical. There are layers to the controversy I haven’t addressed here, including enymatic versus non-enymatic staling mechanisms and the affect of temperature on level of dissolved oxygen in solution. Approaching the problem from a theoretical standpoint may not be the best way to go for most homebrewers.
Well, there’s one way to find out if HSA is worth worrying about if you have the ambition. Brew two batches of beer using recipes and procedures that are identical except for how you treat the hot mash and hot wort. Purposely subject one batch to HSA. In the other batch, strive to minimize HSA. Taste both batches and see if you can detect any negative affects from HSA.
In the HSA batch, be a little rough on the hot side. Stir the mash more vigorously than you normally would. If you have a separate mash tun and lauter tun, dump the mash roughly into the lauter tun when you’re transferring it. Splash the sparge water around a bit, stir the boiling wort noisily — in short, go nuts. For the most severe effect, pour your hot wort through a strainer, Papazian style.
In the minimal HSA batch, treat the mash and wort on the hot side with kid gloves. Stir gently. Don’t splash, and don’t move your wort anywhere until it’s been cooled.
Once the batches are brewed, try a series of side-by-side taste comparisons as the beer ages. Ask yourself: Are there any differences between the beers when they are young? Do they age differently?
Many brewers have tried this (or a similar) experiment and their results differ greatly. Some agree that HSA harms their beer. Many commercial breweries have changed the design of their equipment to minimize hot side aeration. Other brewers say they can’t tell the difference between beer subjected to HSA and beer that was not. Papazian recently wrote to the Homebrew Digest (HBD), an online forum, to say that he still pours his wort through a strainer and it’s never caused him any problems. One HBD participant even claimed that, in a blind taste test, beer drinkers preferred a beer aerated on the hot side to a beer in which HSA was minimized.
Clearly, there is a diversity of opinion about the dangers of HSA. If you really want to know how HSA affects your beer — your recipes, using your procedures and your equipment — you will probably have to do the experiment yourself. Keep in mind that commercial breweries have procedures that differ from homebrewers. They may be able, in some instances, to better control HSA than a homebrewer. For example, some breweries wet-mill their grain in an oxygen-free environment. The wort is then pumped into the mash tun from the bottom, further avoiding contact with air. However interesting, this isn’t an option for homebrewers.
Of course, brewing two batches for experiment’s sake is a lot of work. Some homebrewers, myself included, subscribe to the brewer’s version of Pascal’s wager — HSA may or may not be real, but it doesn’t cost me much to avoid it.
Aluminum Fears…
No part of brewing is safe from controversy. Even the equipment you use to brew can be controversial. For example, some homebrewers claim that using plastic fermenters is an invitation for infection because bacteria can hide in the small scratches that plastic buckets invariably accrue. More seriously, some people claim that one type of material used in some breweries may have serious health consequences. Specifically, it has been suggested that using aluminum pots during brewing can lead to Alzheimer’s disease.
…Are Justified?
Alzheimer’s is a degenerative brain disease that primarily affects older people. Symptoms include memory loss and dementia. Autopsies of Alzheimer’s sufferers have shown that Alzheimer’s patients had an unusually high concentration of aluminum in their brain tissue. A British medical journal, The Lancet, even published a paper linking aluminum in drinking water to Alzheimer’s.
One potential source of aluminum exposure is from cookware, especially cookware used to cook food that have low pH values. At lower pH values, aluminum can be leached from cookware into food. The pH of wort is optimally between 5.2 and 5.6 — not as low as tomato sauce or other high-acid foods, but potentially low enough to cause concern if aluminum were a health risk. Some people jumped to the conclusion that using an aluminum brewpot would lead to aluminum in your beer.
…Are Not Justified!
Critics were quick to point out that finding elevated aluminum levels in the brains of Alzheimer’s suffers does not mean that aluminum caused the disease. It is possible that high aluminum levels are a symptom of the disease, not a cause. The change in brain tissues caused by the disease may lead Alzheimer’s sufferers to retain more aluminum than non-affected people.
In addition, researchers also pointed out that aluminum is an abundant element. In fact, it’s the third most abundant element on earth. The average person receives almost 21 mg of aluminum per day in their diet. Aluminum is found in baking powder. Likewise, antacids may contain up to 50 mg of aluminum. Following the directed dosage, an upset-stomach sufferer may ingest up to 1000 mgs per day. Using aluminum cookware increases the daily amount of aluminum injested only slightly (some sources say by less than 0.5 mg). Critics of the aluminum-Alzheimer’s link say that if aluminum really did cause Alzheimer’s, cookware would be the least of our worries.
Follow-up studies to the original study have been inconclusive. Some researchers claim to have found a general link between age and aluminum levels in the brain. Thus, the aluminum found in the brain tissue in the original study may have been there due to age, not Alzheimer’s. Other studies have found no link between suffering from Alzheimer’s and the presence of aluminum in the brain. Still other researchers have suggested that the metal found in the neurofibrillary tangles of Alzheimer’s patients in the original study actually came from the water used to prepare the tissue samples. They claim the aluminum was introduced by the experiment.
Resolution?
Researchers have judged the studies linking aluminum ingestion to Alzheimer’s to be inconclusive at best. Almost no one who studies Alzheimer’s believes aluminum is a primary factor that causes the disease. Most, in fact, think it has nothing to do with Alzheimer’s. The evidence that aluminum contributes to Alzheimer’s is disputed by most major Alzheimer’s researchers and support groups. If you have an aluminum brewpot, there is no health-related reason to worry about it. Some homebrewers claim that using an aluminum pot adds a metallic taste to their beer, but that’s another controversy for another time.
And in Conclusion…
As a beginning homebrewer, I would frequently read about some homebrewing controversy and decide I needed to change my brewing practices. These days, when I read about these controversies, I think, “Do I really need to worry about this?”
Before rushing off to change the way you brew, pour yourself a homebrew and ask, “Do I need to change my brewing practices … or does my beer taste fine?” It’s easy to get caught up in theoretical arguments about brewing procedures. (Hell, I think it’s fun to get caught up in theoretical arguments about brewing procedures!) But keep your eye (or tastebuds) on the beer you are producing. The point of homebrewing is to brew quality beer . . . and to tell other homebrewers that they’re doing it wrong. Homebrewing can be as simple or as complex as you make it. Some brewers just follow the directions on their extract kit. Others make up their own recipes and fine-tune their brewing procedures in an effort to brew superior beer. Whatever your attitude towards brewing, there is a set of lab equipment for you.
Illustration by Jim Woodward.
