Brewing with All Kinds of Sugar | Craft Beer & Brewing Magazine

Brewing with All Kinds of Sugar

When it comes to adding sugar to your beer there are pitfalls to avoid, and lots of wonderful, complex flavors to gain.

Josh Weikert February 22, 2018

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There are any number of reasons to believe that we live in a golden age of beer and brewing, but one of the most visible and exciting is the fact that brewers at all levels have access to an astonishing array of ingredients with which to create their beer. This is as true for sugars as it is for hops, and while this broad mix of ingredients is thoroughly intriguing it also calls for an equally broad and sophisticated approach to brewing with them. There are brewing pitfalls out there in the periphery of the possible, and as OG and intensity ramp up with added sugar use you increase the probability that you find them!

This piece will explore the use and impact of a range of brewing sugars. Unless you’re a die-hard Reinheitsgebot devotee, there’s no reason why you shouldn’t be taking advantage of these additions, especially as your box fills up with more “conventional” recipes and you start sniffing around for wilder pastures.

Gravity vs. Fermentability

One of the first questions you should be answering is whether the sugar you’re adding is going to add to your beer’s body, flavor, alcohol content, or all three. This is principally a question of the sugar’s fermentability by brewing yeast, and it is a useful starting point in our discussion. Not all sugars are created equally, and while yeast are amazing creatures even they sometimes get stymied by the occasional chemical bond. Sugars generally fall into one of four categories: 100% fermentable, mostly fermentable, partially fermentable, and unfermentable.

Most of the most-common sugar additions to beer are near-completely fermentable. This includes simple sugars and syrups such as corn syrup, table sugar, Belgian candi syrup, and maple syrup. Adding these to your beer will impart gravity points that add almost perfectly to the ABV yield, since every gram of sugar is going to be converted by the yeast into alcohol. Using these sugars virtually guarantees that they will add no body and, in fact, will thin it out as the only residual contribution to the beer, post-fermentation, will be alcohol and (maybe) some flavor compounds, but no residual carbohydrates or proteins.

This is in contrast to the mostly fermentable sugars that we might use. Rice solids, honey, and lighter molasses or treacle varieties are mostly fermentable (ranging from 75 percent to 95 percent fermentability), but nonetheless may contain small but significant amounts of proteins, minerals, or unfermentable sugars such as dextrines which can add body or flavor to a beer. Still, the use of these sugars will yield a substantial percentage of its potential gravity to the fermentables pile, thereby adding to your potential ABV.

From there we drop off significantly in terms of fermentability as we consider the darker molasses and black treacle varieties, which may be as little as 40% fermentable. Molasses and treacle are sugar products, to be certain, but as they’re composed of both the sugars and byproducts of the plants from which they’re derived, they’re not pure fermentable sugar—and the darker they are, the greater their concentration, resulting in a product that is both intense in flavor but also has a far lower yield in terms of fermentable gravity points.

Last, we can consider the least fermentable sugars in a brewer’s arsenal: lactose and maltodextrin. We can think of these as the polar opposites of the near perfectly fermentable sugars, in that they will add gravity points but virtually no alcohol, as they’re composed overwhelmingly of sugar types that are simply unfermentable by brewing yeasts. While it’s possible to introduce enzymes that can break these sugars into usable chunks for our yeast (lactase for lactose, for example), left to their own devices these sugars will add body in the form of unfermentable gravity to your recipe, which is presumably why you’d have chosen them.

A Question of Taste

Tasting a sugar before using it is often a good idea, but it’s naive to assume that the pre-fermentation flavor you perceive will survive the fermentation process. After all, lots of that sugar is going away, and what remains may taste dramatically different. The conversion of sugar into alcohol doesn’t remove all of the sweetness (since alcohol is, itself, sweet in addition to being potentially perfume-like or peppery), but it certainly changes the perception of that flavor in noticeable ways, some more than others.

When we add some sugars and syrups (corn sugar/dextrose, un-caramelized beet sugars and candi syrups, rice solids, cane sugar) we add virtually no flavor at all. Color isn’t necessarily a perfect indicator of flavor contribution, but it’s pretty close: if it’s light in color, it’s probably minimal in flavor. When combined with a very high level of fermentability (like dextrose or Lyle’s Golden Syrup) the net result is alcohol and little else, although excessive use can yield an unpleasant hot flavor. In terms of imparting flavor, it’s hard to do better than honey if you’re looking for options. Ranging from the barely there of clover honey up through the intense and dark buckwheat honey, honey offers a huge range of flavors for brewing. These flavors are, incidentally, quite unconnected to the floral source of the honey: “raspberry honey” tastes not at all like raspberries. The flavors are truly staggering, with the marshmallow-like flavor of Meadowfoam honey to the richness of Tupelo honey, the floral notes of orange blossom honey, and more. These flavors, especially in the darker varieties, can be quite persistent even post-fermentation.

Another source of brewing sugar is saps (or natural syrups). Agave syrup or nectar—the very thing used to create tequila, when drawn from the blue agave!—is almost sharply sweet, and post-fermentation lends a bright tropical fruit flavor to the beer that itself lends an impression of sweetness. Jaggery is a palm sap with African/Asian roots that, like honey, varies in color and intensity; the lighter versions can taste like toasted peanuts, while darker versions can add fig and plum flavors.

Then we have the classics like maple or birch syrup. These can be devilishly tricky to work with, since although they have distinct and noticeable flavors pre-fermentation, after their sugars are fermented off they can nearly disappear entirely! Using the lesser-quality grades of syrup (AA or B) increases the odds of retaining some of their rustic flavor, but even there it’s a good idea to plan on the use of a spice such as fenugreek to round out the expected “breakfast-time” flavors! Then we have the intense flavors of molasses and treacle. The darker the sugar, the greater the chance it has been caramelized and/or concentrated, and the resulting flavors can be quite intense.

Lighter-colored molasses can be used to deepen the toffee-like flavors we often see in crystal malts, but as we move towards blackstrap molasses and black treacle, the flavors become potentially overpowering. If you’re looking for a rich, bitter flavor punch in a porter or stout, feel free to reach for the dark molasses—but always add it sparingly, and build up in successive recipes to find the intensity level you can live with. This is also an appropriate time to add a PSA: be very careful with brown sugar in beer. Brown sugar is essentially just table sugar with an addition of molasses—once the completely fermentable table sugar disappears, you’re left with pure, unadulterated molasses, which might be excessively sulfurous or bitter on its own.

Finally, a brief word about Belgian candi sugars/syrups and flavor. To be certain, when you taste these sugars pre-fermentation they certainly do convey different flavors based on their color. Having said that, they (much like the maple syrup mentioned above) are completely fermented off in the brewing process, and impart only subtle flavors even when using the darkest varieties. They will add color, and they may accent or augment some of the dark flavors you’re already pulling from your darker crystal malts, but I would not count on them as a primary source of flavor. If you’re in the market for that, it’s time to start playing with the molasses.

Recipe and Process Considerations

The first step in adjunct sugar usage is deciding just what it is you want out of your sugars. Perhaps the most common usage is to increase the potential ABV of a beer. If that’s your primary consideration, be sure to choose a sugar with a high fermentability percentage. This is a common feature in Belgian strong ales, where the goal is a beer that is high in ABV but light in body, and for that prescription you can’t do much better than the lighter candi sugars. If, however, you want to add body, then you’ll want to consider dextrin powder (if you don’t want residual sweetness) or lactose (if you do). You can back sweeten with a fermentable sugar, but to keep the yeast from chewing it up and spitting it out you’ll need to add potassium sorbate (or pasteurize, but that’s a bit more radical). In any case, you’ll want to consider whether there’s an adjustment to the grist, mash, or process you’d like to make to account for your sugar addition.

Once you’ve settled on the body/ABV adjustment (if any), consider the flavors added. This could be the principle consideration or just a side effect of your chosen sugar, but regardless you’ll want to select a sugar knowing what its post-fermentation flavor will be, and how it will contribute to the target flavor of your beer. Sometimes this is a case of trial and error, but there’s a growing body of reliable reviews and feedback online to guide you the first time out. This is a time when a clone recipe might be a great guide, since you can taste the finished product in advance and adjust from there.

We’ve adjusted our recipe and set our sights: it’s time to add the sugar. As a general rule, the more flavor we want out of an ingredient, the later in the process we’ll want to add it. If it’s a particularly dominant flavor (dark molasses) or a nonexistent one (corn sugar), there’s no reason not to add it in the boil. For more-subtle flavors, though—most honeys, pale jaggery or molasses, candi sugar —you’ll want to at least consider adding them in a secondary vessel, post-primary fermentation. This has the added benefit of letting you taste your beer in-process and potentially adjusting your recipe to taste, on the spot. In any case, you’ll want to take care to mix your sugars in thoroughly. This is most-easily accomplished by mixing into a small portion of wort (or beer, if in secondary) to dissolve the sugar (or thin the syrup), then stirring the mixture back into the beer. If adding mid-boil directly into the kettle, kill the heat first to avoid scorching. And working even further backwards in time, I can’t conceive of any reason to add sugars in the mash, though you might add an unusual mashable grain at that stage.

You’ll also want to consider whether your recipe is properly balancing the additional sweetness (or impressions of sweetness) that remain in the finished beer. Keep in mind that alcohols can be harsh at first, but will likely age out into a more-mellow and sweeter flavor in addition to any actual sweet sugars that don’t ferment off. Adjust IBUs and carbonation levels accordingly to help balance out those flavors to limit the risk of producing a cloying beer.

A Happy Fermentation

One final—but vital—consideration relates to yeast. After all, we just make wort and yeast makes beer. Especially if you’re aiming high in terms of ABV (and if you’re reading this, you probably are), you want to consider the relationship between the number of yeast cells and your gravity. High-ABV beers are about more than simply choosing a yeast strain that has a high tolerance for alcohol toxicity (though that’s important, too). You also need to consider the osmotic pressure on the yeast cells, which are designed to “begin as they mean to go on.” If they find themselves in a substantially “dense” wort, there’s a mismatch between the osmotic pressure in the wort and in the yeast cells, and the yeast will ferment it differently than if they were in a more conventionally composed wort of moderate sugar content. That mismatch can cause hiccups in metabolism, incomplete fermentation, off-flavors, hot alcohols, and more—none of which we want. Difficulty in fermentation increases with ABV, but you don’t want to make this harder by creating an “extreme” wort for your yeast to process.

The answer is to take a measured approach to the fermentation. First, ensure that you pitch a larger-than-usual dose of healthy yeast, in proportion to your total original gravity. Second, add your sugars in sequence rather than all at once: mash, lauter, sparge, and boil, then pitch your yeast, and only once they’re finished with the mash-derived sugars do you start adding your adjunct sugars. This way, you don’t overload your yeast at the outset. Third, ferment cool to begin with, and increase temperature slowly. This will reduce the precursors and off-flavors in the “easy-going” part of the fermentation, which will buy you some leeway later on when things start to get hairy. Last, consider whether additional yeast nutrient additions (DAP, FAN, Yeastex, etc.) are necessary to keep the yeast supplied with the minerals and compounds necessary to promote continued healthy fermentation.

Keep your yeast happy and healthy, and you’re far ahead of the game.

Sugar, Sugar, Everywhere

One final note before you start scouring the homebrew shop and internet for the best and most exotic sugars: keep in mind that sugars can be found in lots of atypical ingredients! Some are conventional, if not universal, like fruit. Others, though, can be found in candy, breakfast cereals and other mashable grains, juices, condiments, and more. Be creative. Brewing is a pretty robust process, and so long as we’re talking about fermentable sugars it may not matter what other ingredients are surrounding them. Consider throwing that Korean BBQ sauce in and seeing what it does to your favorite Stout. Add your favorite sugary cereal to your mash tun. Chop up your favorite candy bar and add it to the secondary of your Old Ale.

Just account for the sugar, and sit back to watch the fireworks. Happy brewing, everybody!

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