1. My beer fermented for 2 days and now the airlock has stopped bubbling. What have I done?

2. My beer has been fermenting for 2 weeks and it is still bubbling. Will it ever end?

3. The directions on this can of malt are totally different from those in my book. What's the deal?

4. What's the difference between liquid and dry malt extract?

5. What's the difference between leaf hops and pellet hops?

My beer fermented for 2 days and now the airlock has stopped bubbling. What have I done?

There are three factors involved here, and we'll deal with each one separately.

• Trust your yeast. Reading all of those foreign instructions and brewing books when you were getting started may have made everything seem so technical and unforgiving that brewing seemed more challenging than it was fun. Not so. Now that you've done it a time or two, you realize it's not as complicated as it sounded. And not as unforgiving. But yeast is a living, eating, multiplying organism, and it is not always going to act exactly as you expect it. There are many factors affecting the speed of your fermentation: the amount of oxygen in your wort, the number of yeast cells initially pitched, the amount and type of fermentable sugars in your wort, and the temperature of your fermentation, to name a few. Since each of these has a big impact on the way the yeast ferments, there can be large variations in the way your fermentation proceeds. Sometimes, we get the disconcerting thrill of exploding fermentor lids. Other times, barely enough activity to make it fun to watch your airlock.

  With some experience, you'll learn the tricks of taking better control of your fermentation activity, and you may better control the length of your fermentation. But you'll never completely control it, and learning which problems are minor and which ones are major is a big part of becoming a good brewer. In this case, even if you're fermentation did stop prematurely, it's no big deal. A stuck ferment can be solved by doing one or more of the following: moving the fermentor to a warmer spot, stirring the wort, or adding yeast nutrient. If your yeast is dead, you can just add more yeast. No problem.

• Question your airlock. Though it can give you a general idea of how things are going, it will never tell you exactly what you need to know. If the CO₂ found a tiny hole to escape through instead of your airlock, and you bottled your still-fermenting beer, all the extra CO₂ created in the bottle make for a big carbonated mess when you pop the cap. Conversely, if the CO₂ coming through your airlock is not from current activity, but is just seeping out of solution from past fermentation, then you're waiting for something which may not end for weeks--even though your beer is ready for bottling. When these questions are raised, it is best to answer them with a hydrometer, possibly the most important instrument for monitoring fermentation. If you don't have one, buy one. If you have one, use it. With it, you can see if the wort is at it's expected teminal point. If not, you can use successive readings to see if the gravity is changing, in which case your fermentation is still occuring. When the readings have reached their expected level and have stabilized, you're ready for bottling.

• Relax. We have enough experience helping beginning brewers to understand why brewing guru Charlie Papazian coined the mantra of homebrewing: "Relax, don't worry, have a homebrew." Don't assume that every unexpected development spells doom for your entire batch. It is always better to be overcautious about things like sanitation and such than it is to be lackadaisical. But most facets of homebrewing are much more forgiving than beginners are lead to believe.

My beer has been fermenting for 2 weeks and it is still bubbling. Will it ever end?

This is kind of the corollary to the question above, and much of the answer is related. If you haven't read the statements above about trusting your yeast and distrusting your airlock, you may want to give them a peek.

Using your hydrometer becomes very important at the end of your fermentation. True, you're beer could still be fermenting. But it might just be that CO₂ is coming out of solution. After fermentation, there is a certain amount of CO₂ that was created as a byproduct but did not escape from solution as gas and pass through your airlock. In fact, the fermentation process totally saturates your wort with CO₂. Depending on changes in temperature and other variables, it may slowly escape from solution over a period of weeks. Just like you soda pop bubbles after you open it--without any fermentation occuring--so may your wort bubble slowly.

There is no way of knowing if this bubbling is fermentation or simple bubbling without using a hydrometer. Use it to see if the wort is at it's expected teminal point. If not, you can use successive readings to see if the gravity is changing, in which case your fermentation really is still occuring. If it has been fermenting for quite a while, try moving your fermenter to a warmer spot to speed it up. When the readings have reached their expected level and have stabilized, you're ready for bottling--even if you airlock is bubbling slowly.

The directions on this can of malt are totally different from those in my book. What's the deal?

We understand your dilemma. Unfortunately, there is little that can be done to remedy this problem. But our advice is to ignore the directions on the can. Though this may seem like bad advice, it is perfectly logical. One part of the problem is that many, if not most, malt extracts, are produced in England, where a gallon is not a gallon. That is, a gallon on a can of British malt extract is not a gallon in your American carboy. The british use Imperial measurements, which are actually larger than our own. So all of the volume measurements on that British can are different from the ones we use here in the states.

Your can says to make three gallons from the can alone, which really equates to 3.6 US gallons, which obviously doesn't fill up your fermentor. Even when the measurements are the familiar ones, malt cans usually ask you to adjust your batch size to the amount of ingredients in the can. This makes sense, since the manufacturer wants to be selling you a self-sufficient product. But most homebrewers adjust their ingredients to the established batch size of 5 US gallons, and it's best to accept this general trend to brew five gallons. In doing so, you avoid many problems with equipment size, recipe formulation, and brewing instructions. This is especially true when you are just starting out.

What's the difference between liquid and dry malt extract?

The only real difference between liquid and dry malt is how it is packaged. The dry malt has nearly every trace of water evaporated from it, so it ends up as a powder. Generally, liquid malt retains about 20% water by weight, so it is in syrup form. Though this does not greatly affect the malt extract itself, it does affect your brewing process. For one thing, you should consider dry malt to be more concentrated than liquid (since 20% of the liquid malt weight is just water). If you'd like to convert from one to the other, you should use .8 pounds dry malt for each pound of liquid, or 1.25 pounds of liquid for every pound of dry malt.

Much like the argument between brewers preferring a particular form of hops (leaf, pellet, or plug), there are arguments for and against each kind of extract. Some say that dry malts are less fermentable since they have to be reconstituted--thus, they leave a maltier flavor. Some say that dry malts are easier to store, since their dryness makes them less susceptible to spoilage. Our opinion here at the Cellar is that you should use whichever gives you the best results or makes your brewing easier. With years of brewing and tasting, we have found no significant difference between the two forms. But we do recommend experimenting with both.

What's the difference between leaf hops and pellet hops?

Like the difference between the malt extract forms, the difference here is simply the means of packaging the product. However, the results of these two processes should be considered when you are deciding on which form to buy. We'll consider each aspect separately:

• Ease of use: Most brewers consider the pellets easier to use, since they basically disintegrate into the wort during the boil. They do not need to be strained out after the boil, and they precipitate during fermentation, to be cleaned away with the rest of the sediment. In other words, there is really no work or extra equipment involved in using them.

  The leaf form is usually placed in a nylon or mesh strainer bag during the boil, or strained out afterwords with a collander or strainer. This is not difficult, but it does require some sort of strainer or boiling bag.

• Bitterness: When considering the difference between the bittering potential of the hop forms, we must consider both the amount of bitterness they have and the amount they give to the beer. Pellets generally give more of their bitterness (alpha acids), since they are already pulvarized and simply disintegrate into the boiling wort. However, the leaf forms usually have slightly more bitterness, since none of the alpha acids are lost to the pelletizing process used for the other form. Then again, leaf hops lose more of their bitterness during periods of storage, since they have more surface area exposed to heat, oxygen, and light. So the matter is not clear cut.

  In the end, your best bet is to find out what the alpha acid levels of each form are, and compare them to the recipe's level if it gives one. Weigh these facts with your own preferences in deciding which form to use. Since both forms give excellent results, it will most likely boil down to deciding which form is easiest.

• Flavor: Always remember that flavor is not just what your tongue is telling you about your food. All your tongue can say is "sweet," "salt," "sour," or "bitter." Flavor gets the rest of it's vocabulary from your nose. And the aroma of hops is a major, major factor in the way we perceive a beer's flavor.

  Purists will say that the aroma hops ("finishing" hops, used at the end of the boil or after it) must be leaf hops. The delicate oils found on the hop flower are responsible for the hop's wonderful aroma, they say, and the hops should arrive at the brewhouse with as little processing as possible. Why would you want to pelletize something that's too sensitive to be boiled for more than a short time? Well, we understand their point. And some of us believe it enough to choose only leaf hops even for boiling.

  But, again, it is important to understand that you can achieve excellent flavor from either hop form, and that you're allegiance to one form or the other will develop only with experience, if it does at all.