Dear Mr. Wizard,
Strawberries are in season and I’m about to make my first fruit ale. I’m a devoted extract brewer, but the addition of fruit is new to me. Scanning the Internet, I’ve found a few recipes that look good, so I’m going to formulate a recipe based on what I’ve read. However, I’m a little confused as to the purpose of pectic enzyme. How much do I use? I understand it comes as a powder as well as a liquid. Do I add it to the primary or secondary fermenter? Also, how is the yeast going to react to the sugars in the berries? A friend told me to run a blow-off tube because there will be so much action in the primary fermenter that my 6.5- gallon fermenter will overflow. My next venture will be with blueberries — we have a pub in Bar Harbor that makes a wicked blueberry ale. Will I need pectic enzyme with blueberries as well?
Mr. Wizard replies:
This question reminds me of one of the goofiest names I ever gave a batch of beer — Strawberry Fields For Alever. It was a wheat beer with strawberries added after primary fermentation was complete, and it had an interesting pink, cloudy appearance with a nice, fruity nose. I like adding fruit to beer after primary fermentation because of the good retention of fresh fruit aromas and colors. If fruit is added to the primary, special care must be used to prevent potential carboy bombs. The fermentation lock can get plugged and pressure can build up inside the fermenter. The safest method is to ferment the beer in a plastic bucket with a large lid and an airlock. A blow-off tube on a carboy can also be used, but it too can clog and this can be dangerous.
The last two issues of BYO — the July-August 2002 issue and the September 2002 issue — contained a two-part article on fruit beers. Check these out for information on formulating and brewing fruit beers. I will tackle the question regarding pectin here. Pectin is a type of carbohydrate found in fruits that act as a structural member of the fruit, kind of like beta glucan in cereal grains. In cooking, pectin is useful for its ability to form a gel when heated in a sugar solution with a low pH. This is why jams and jellies are thick and stay on your toast or bagel instead of running off.
Although all fruits contain some pectin, many do not contain enough for making jams and jellies and many fruit spreads use pectin from other sources than the fruit being used. Certain varieties of apples, such as Granny Smith, are well-known for their especially high pectin contents.
When it comes to brewing and winemaking, pectin levels are usually kept low for two main reasons. The first is the haze pectin can cause; pectin hazes are due to the very large size of the pectin molecule and the tendency for the molecule to form gels. This is analogous to starch hazes. This is a cosmetic issue that some of us don’t worry too much about, depending on the beer style being made. My strawberry wheat beer was cloudy, but wheat beers are typically cloudy and the cloud looked cool in that beer. Cloudiness, these days, is in fashion and some of those wimpy malternatives, like Smirnoff Ice and Mike’s Hard Lemonade, actually include ingredients to make them permanently cloudy. A friend of mine was in a brewery that was making — I dare not use the term “brewing” — some of these things and he saw a big container of something called “cloud.” This was the special ingredient to make it look interesting. When you make a fruit beer at home, you can omit the “cloud.”
The other thing about pectin is that filtration becomes very, very difficult. The reason for this is again the large size of the molecule and its gelling properties. I make a hard cider every year. A couple of years ago I set up the filter, sent the cider to it as I had done in the past and wham! — the flow immediately slowed to a stop in a matter of seconds. When the filter was broken down, there was a distinctive orange film on the filter. Although the film was thin, it was so tight that cider simply could not pass through it.
The solution to this problem was to buy a liquid pectinase that I then added to the cider. Pectinase enzymes reduce the size of the pectin molecule and also prevent the fragments from gelling. About a week later, filtration was a breeze. What I should have done was to perform an easy test for pectin before filtration. To check for the presence of pectin, simply add one part of the wort, beer or wine to one part 70% alcohol. Ethanol and iso-propanol both work. I use iso-propanol (rubbing alcohol) because it’s cheap. This test will cause pectin to gel. When this occurs, the sample becomes cloudy and the pectin begins to precipitate and will eventually settle on the bottom of the sample glass.
Although this method is not quantitative, you can get a feel for the pectin concentration. If the haze is detectable, but very slight, you may decide not to worry. If the sample looks like orange juice after adding the alcohol, you probably will choose to deal with the pectin. Fortunately, it’s simple to address this problem. The easiest thing to do is to add some pectinase to the fruit mush before adding the fruit to your beer. You can use dry or liquid pectinase — follow the recommendations with the enzyme regarding usage rate. The other approach to take, especially if you don’t like adding stuff unnecessarily to your beer, is to do a test after fermentation is complete and the fruit has been added. If the sample indicates a pectin problem, then add your enzyme at this stage.
As I stated earlier, all fruits contain some pectin. According to my handydandy book entitled “Preserving” (1981, Time-Life Books), tart apples, citrus fruits, cranberries, currants, gooseberries and sour plums all have “high” pectin levels. Interestingly, all of these fruits also rank high in natural acid levels and these fruits make great jams and jellies without requiring an exogenous (outside) source of pectin. Strawberries, peaches, pear, pineapple, apricots and rhubarb all have a low pectin content. Cherries, blueberries, blackberries and raspberries all have a medium level of pectin. I think I see a pattern here — it seems like brewers typically make fruit beers with fruits that have a low-to-medium pectin level. Makes sense to me!
Dear Mr. Wizard,
My current stainless-steel brew pot is only five gallons and has developed a crack in the rim. I need to replace it with something larger that will not break my bank account and send my wife into a frenzy. I know that stainless is highly recommended for use as a brew kettle and I understand why, but are there any cheaper alternatives? I have read articles, including one by you, that say that using aluminum can be OK. Is this true? Also, what about the ceramic canning kettles that are readily available?
Lock Haven, PA
Mr. Wizard replies:
A pot really only needs to satisfy a few simple requirements to become a qualified brew pot. For starters, it ought not to leak — a leaky kettle is a problem. A good candidate for the job should also be large enough to hold a whole batch of wort. In your case, that means 5.5 to 6 gallons of wort before boiling, plus about 20 percent extra space to prevent boilovers. Using this formula, you need about a seven-gallon kettle. If you can, it is much better to boil the whole volume of wort instead of doing a concentrated wort boil. A concentrated boil affects hop utilization, aroma changes to wort during boiling and color development much differently than doing a full wort-volume boil. The kettle should also be constructed from a material that can adequately conduct heat from the heat source to the wort. This is one property of stainless steel that is less than stellar. The final qualifier for the kettle is that it should not harm the wort by leaching compounds into it.
Stainless steel is certainly the most common material for kettle construction nowadays. Stainless steel is inert, is easily formed and welded and can be heated either by direct flame or with the use of steam jackets and coils. Steam is used by commercial brewers because it does not result in scorching. Unfortunately, stainless steel kettles are pretty spendy. A seven-gallon stainless steel pot can easily cost more than $150.
Ceramic canning vessels, also known as crab or lobster pots, certainly meet the basic requirements for a kettle. Canning vessels are usually made of tin with a thin enamel coating. These vessels are inert, have a high heat conductivity and they are less expensive than stainless pots. One drawback to ceramic pots is that you cannot weld a valve to them because the ceramic coating chips off. In addition, if they get chipped or cracked, the metal under the ceramic is not inert. If you are careful with how you handle these pots and don’t mind not having an outlet valve, then this is one viable option. A minor drawback is that the handles of canning pots are not very strong and you should not attempt to lift a pot full of near-boiling wort. This is dangerous regardless of the handles and really ought to be avoided.
Aluminum pots are readily available in all sorts of sizes, are really inexpensive and have a terrific thermal conductivity. An outlet valve can be welded to an aluminum pot, but you will probably have a difficult time finding anyone who can weld a stainless steel ferrule to an aluminum pot because aluminum welding is a fairly specialized technique. The other issue with aluminum is that it is not inert. The main problem with this feature, especially in commercial applications, is that aluminum is readily dissolved by sodium hydroxide (commonly known as caustic) and caustic-based cleaners are the workhorse cleaners of the food and beverage industries. Any cleaner containing sodium hydroxide will have it on the label because sodium hydroxide is pretty nasty. Draino and Easy-Off both contain sodium hydroxide. The best advice is to read the label.
Aluminum has also been associated with Alzheimer’s disease and some have suggested that there may be some cause-and-effect relationship with the two, but I haven’t seen or read anything very convincing on that idea. Keep in mind that aluminum is a very commonly used metal for making all sorts of cooking utensils. If you don’t need an outlet valve and don’t use caustics, an aluminum kettle is fine.
The granddaddies of all kettles are ones made from copper. These dudes look great, have the highest thermal conductivity of all metals and are traditional. However, copper is expensive, difficult to weld (soldering is typically used on copper and this is easy) and is not inert. Copper not commonly used anymore for making big pots. I hope you didn’t have your heart set on copper! Those are some ideas on kettles. One option many homebrewers take is to convert an old beer keg into a kettle. These make good kettles, but I feel obligated to remind everyone that stainless-steel beer kegs are the property of breweries. The paltry $10 deposit is only a small fraction of the true cost of a beer keg. If you use a keg for a kettle, make sure you buy the keg from its true owner and help prevent keg float shrinkage! (Breweries refer to kegs out of the brewery as a “keg float.” Shrinkage refers to theft. What I’m trying to politely say is, give breweries a break and don’t steal kegs!)
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