Q: You mentioned that you use a GLP-1 drug. What has your experience been with beer consumption while taking it?
David Hernandez • Springfield, Missouri

Mr. Wizard says…

A. I was diagnosed with Type 2 diabetes in the spring of 2023 during a routine check-up. For those of you not well-versed in this subject, here’s a brief overview. Type 2 — sometimes called adult-onset — diabetes is the form that emerges later in life. Unlike Type 1 diabetes, Type 2 treatment these days does not typically include insulin injections.

At first, I was a bit shocked because this wasn’t something I had spent much time thinking about. But soon enough, it was time to follow my doctor’s advice. I responded well to the two prescribed drugs, and my A1C level — a measure of hemoglobin-bound glucose and an indicator of average blood glucose concentration over the roughly three-month lifespan of a red blood cell — quickly fell into the normal range. I dodged a bullet and my eyes were opened to GLP-1 drugs, and soon I was able to get a prescription for Mounjaro.

Mounjaro, unlike other GLP-1 drugs on the market, is a combination of GLP-1 and GIP agonists. These compounds mimic hormones related to glucose metabolism, increasing insulin release after eating or drinking while often decreasing glucagon (which raises blood sugar), slowing digestion, and reducing cravings. One key to my journey through all of this has been my use of a continuous blood glucose monitor, or CGM. Although I could have stopped using one long ago because of my successful treatment, I continue to wear a CGM. They’re inexpensive when covered by insurance, and they provide incredible, continuous, real-time data.

I quickly discovered that I was my own walking test subject. Eat this, drink that, take a walk, sit on my tail — and check out the results! The first thing that became apparent was that consuming starchy foods like bread and rice caused a quick spike in blood glucose. Not a huge surprise, but it hits differently when you see the data streaming live on your phone. Interestingly, my spikes were reduced when I ate veggies and/or protein along with bread or rice. Another quick discovery: Walking after eating has a big effect on how long those spikes last. Even a relatively short walk is effective in reducing the intensity and duration of post-meal glucose spikes. Nothing too shocking so far — but what about beer and other alcoholic beverages?

Alcohol consumption was where things got surprising for this formerly ignorant guy with Type 2 diabetes. Alcohol often lowers blood glucose levels. Because I use a CGM, I quickly discovered that low-glucose alarms coincided with having a beer on an empty stomach. Interesting! I also found that certain types of beer were worse than eating a big chunk of bread or a small portion of rice. These included beers with high finishing gravities — often not obviously sweet — massive imperial stouts, and even some non-alcoholic (NA) beers. Seeing spikes after drinking NAs was a surprise and opened my eyes to different types of NAs in the market.

The last major realization was the powerful effect Mounjaro has on my appetite. At first, the effect wasn’t noticeable. The dosage of these drugs is slowly increased over several months because jumping straight to a high dose can cause nausea. Even low doses don’t sit well with some people, and not everyone can tolerate these drugs. Luckily for me, I’ve never had an issue. As my dosage was gradually increased, I discovered that overindulgence in almost anything resulted in an extreme sensation of fullness.

I know this is a major departure from my usual brewing discussions, but the sad truth is that my story is all too common these days. My experience may become yours one day. See that as a good thing, because my disease was spotted before it became a serious problem. You asked about my experience with beer consumption, and I’ve finally built up to the crux of your question.

Beer makes me feel full. In my world, that just sucks because beer is at the center of my profession. I still love it, but drinking something like a liter of festbier takes a bit of planning. And here we are — threading the needle of being on a wonder drug like Mounjaro, with all its benefits, while still wanting to drink beer like a rockstar.

Listen up, folks who are in the same boat: Start brewing beers with lower OGs, because those big, burly beasts we all know and love push all the wrong buttons in the “feeling way too full” department. Highly hopped beers — especially hazies — also fill me up. What doesn’t seem to make me feel full includes wine, dry beers (even those with big malty flavors), moderately hopped beers, and beers with balanced flavor profiles. That last one’s a bit of a shocker. In the past, I could muscle through unbalanced beers, but not these days. Lucky for me, most German-style, balanced IPAs, and nitro beers remain easy for me to enjoy without being bloated.

In brewing, dissolved oxygen (DO) is measured for two reasons. The first is to determine that sufficient oxygen is dissolved in wort to initiate a clean, vigorous fermentation. The second is to determine that a low enough level remains in packaged beer to prevent staling. For homebrewers and nanobrewers, the aeration of wort is the primary consideration, which is just as well since measuring the very low level in packaged beer is a much more advanced and expensive technique. BYO’s Technical Editor Ashton Lewis breaks down DO so you can better understand this topic often overheard in breweries.

Refractometers are widely used in the wine and beer industry to measure sugar, but they are less commonly used by homebrewers. However, if used properly a refractometer can be a great tool to measure specific gravity in place of, or to supplement, your hydrometer. It is used primarily in brewing beer to determine the specific gravity readings of wort. BYO’s Technical Editor Ashton Lewis walks through how to use one.

Even the smallest of breweries need to run certain quality control tests on their beer and can without taking up too much space, resources or cost. QC expert Audrey Skinner will walk you through the tests and equipment you need to make sure the beer you are selling to customers is the best it can be.

PDF of Presentation Slides: https://byo.com/wp-content/uploads/Audrey_Skinner_NanoCon-2025-Setting-Up-A-Small-Scale-QC-Lab-1.pdf

In order to brew high alcohol beers, three challenges must be addressed. The first is the production of wort with the potential for a high degree of fermentation. The second challenge is producing high gravity wort. The combination of high original gravity with high degree of fermentation gives you the chance of producing the big beers you seek. The third challenge is carrying out the fermentation without problems from unhappy yeast. Brew Your Own’s Technical Editor Ashton Lewis offers tips on brewing and fermenting beers with a high alcohol percentage.

As an avowed fan of rich, dark beers like porters and stouts, a big body and mouthfeel is something I’ve focused quite a bit on in my 38 years as a homebrewer. In addition to the malt/hop balance, overall aroma and flavor, body is one of the critical features you must get right to achieve perfection in a beer.

This is not to say that all beers should be full-bodied. Many lagers, session, and summer beers require a thin, light body to maximize drinkability. The key, of course, is to match the body to the style and effect you are trying to achieve in the finished beer so the whole is greater than the sum of its parts.

Mouthfeel vs. Body

The terms “mouthfeel” and “body” are often used interchangeably in brewing, and indeed it is hard to separate them. Mouthfeel is perhaps the broader term, being defined by Merriam-Webster as “the sensation created by food or drink in the mouth.” I like this definition as it captures the perception of beer in the mouth, which may be a combination of many ingredients, chemical reactions, and techniques.

In contrast, Merriam-Webster defines “body” as “fullness and richness of flavor,” or alternately “denseness, fullness, or firmness of texture.” This is a somewhat narrower definition, as one might imagine a thin-bodied beer that is still rich in flavor. Body and flavor are not necessarily synonymous in my mind.

I think the key point here is that it is the perception of body that matters most. Individual aspects of the beer like finishing gravity, bitterness, carbonation, flavor, and unfermented sugars all drive the mouthfeel and body of the beer, but it is the combined effect on the drinker that matters.

The body of beer cannot be easily measured, as it is an overall perception and not a number from a machine. One needs to sample a beer to determine its body. When judging the body of beer, it is common to speak of a scale that varies from thin- or light-bodied beers to medium-bodied, to rich- or full-bodied beers.

Contributors to Beer Body

The perceived body of a beer is driven by many factors. We will explore each of these in more detail, but I want to first introduce some of the key drivers:

Carbon Dioxide (and Nitrogen) – The carbonation level of the beer drives its perceived body. Beers higher in carbonation have more mouthfeel and are perceived as having more body. Beers like Guinness that are carbonated with a nitrogen mix have even more mouthfeel than beers carbonated with just CO₂.

Foam – Related to carbonation, a beer with a creamy head of foam is perceived as having more body. Interestingly, polyphenols from both malt and hops play a role in foam retention, so beers high in hops can be perceived to have more body.

Proteins in Malt – All malts and grains contain some level of protein, and protein is one of the biggest contributors to perceived body.  Beta-glucans and gums in malts also contribute body to a finished beer.

Unfermentable Sugars and Carbohydrates – A portion of the complex carbohydrates from grains are typically not completely broken down into fermentable sugars in the mash and remain as residual carbohydrates. Like proteins, these long chains of sugars contribute mouthfeel and body to the finished beer.

Yeast Selection – Yeast selection drives the attenuation and fermentability of the beer, but it also drives the overall flavor profile, which can affect the perception of body. Even residual yeast itself can be used in suspension for beers like hefeweizen to increase the perception of body.

Alcohol and Gravity Level – Beers higher in alcohol create a warming sensation in the mouth and are perceived as having more body. A high starting gravity produces more alcohol for a given yeast strain, increasing the perception of warmth and body.

Tannins – Tannins are a naturally occurring plant compound found in both malt and hops. In the mouth, tannins are attracted to proteins in our saliva and react with these proteins and coagulate, creating a sensation known as astringency. Astringency creates a dry, crisper mouthfeel for the drinker, though in excess they can be distasteful.

Dark Malts – While many beer drinkers think that dark beers inherently have more body, this is not always so. However, dark malts do have a higher level of unfermentable sugars. This is because dark roasted, caramel, and kilned malts have converted some of the fermentable sugar chains into unfermentable as part of the roasting process. 

As I mentioned earlier, the goal with a certain recipe could be a full-bodied beer, very light-bodied beer, or anything in between, so you need to consider all of these factors in combination when designing a beer. Having covered the basic factors, we can now dive into each individual factor in more detail.

Carbonation and Foam

The level of carbonation drives the mouthfeel and perceived body of beer. Higher carbonation levels like those used in many Continental European beers will increase mouthfeel, while low carbonation will reduce it.

If you take the extra step of using a nitrogen/carbon dioxide mix, also called a stout mix, to carbonate your beer as draft Guinness does, it will enhance the perception of body even more. It’s interesting to note that draft Guinness has a relatively low original gravity and alcohol level, but the addition of a large portion of flaked barley, dark malts, and nitrogen mix carbonation creates one of the biggest mouthfeel/body perceptions of any beer.

Foam also plays a huge role in the perception of beer body. The captured CO₂ bubbles at the top of the beer provide mouthfeel when you sip the beer. Proteins and dextrins, will enhance the head retention in a beer. However, many brewers don’t realize that hops also play a role. Alpha acids, which are the primary bittering compound in beer, enhance head retention, as do polyphenols from the hops themselves. A very hoppy IPA will have better head retention than a lightly hopped session beer.

Malt Selection and Protein Levels

Protein is one of the easiest factors to control since the malt data sheet for a given malt will typically show the protein percentage. If targeting a big, rich-bodied beer you can use malts with higher protein levels. Obviously, low protein levels are desirable for light-bodied beers.

One note of caution, however, is that proteins also tend to reduce clarity in light-colored beers, so if you use a bunch of high-protein adjuncts in your beer it can cause serious clarity issues. Looking at protein numbers from various maltsters, several things stand out. Unmalted grains such as flaked oats, flaked or torrified wheat or barley, and black (stout roast) barley all have the highest percentages of proteins. Below that we have caramel and crystal malts like Carafoam^®, Caraamber^®, and various colored caramel malts. Next come the darker roasted and kilned malts.

If your goal is to have less body and less protein, the lighter base malts like Pilsner are a good choice. Not surprisingly, 6-row barley varieties have higher protein levels than 2-row varieties. Also, American barleys tend to have a higher protein content than their European cousins, though some traditional British malts do have high protein levels.

Unfermentable Carbohydrates and Mashing

Yeast will consume simple sugars like maltose and glucose, leaving more complex carbohydrates untouched. Because we can influence the amount of unfermentable sugars remaining post-fermentation through our choice of malts, mash temperature, and yeast, we can drive the attenuation of the yeast and how much body remains.

Malt selection again plays an important role. In addition to considering how much protein a malt has, we also want to consider how much unfermentable sugars like dextrin the malt contains. For example, malts like Carafoam^®, Carapils^®, dextrin, and chit contain more dextrins and are often used to add body to beer. Unmalted adjuncts like flaked barley and flaked oats also contain a high percentage of unfermentable sugars. As will be covered later, dark malts also have a lower percentage of fermentable sugars because many of the fermentable sugars are broken down during roasting and kilning.

The next factor a brewer can easily control is mash temperature. Because the two major enzymes — alpha and beta amylase — reach their peak effectiveness at different temperatures, you can adjust your mash temperature to promote more or less fermentable sugars and therefore drive a lower or higher body in the finished beer.

Selecting a high mash temperature around 156–158 °F (69–70 °C) will create less fermentable sugars and create a beer with a full body. Using low mash temperatures in the 148 °F (64 °C) range will promote more fermentable sugars leaving a lighter body in the finished beer. If you hold steps at both temperatures, often called a lager mash profile, you can promote even more fermentability and less body than just mashing the low temperature range.

Yeast Selection

Another consideration is the choice of yeast strain. Each yeast strain has a published “attenuation” parameter as part of the yeast data sheet. Attenuation is the “apparent” percent of sugars that are fermented by the yeast strain in a standard wort. Yeast labs usually list the apparent attenuation, which differs from the real attenuation only in the fact that real attenuation is corrected to account for the fact that alcohol has a gravity below 1.000, while the apparent attenuation can be measured directly. The average attenuation for many yeast strains is around 70%.

If you choose a yeast with low attenuation, it will leave more body in the finished beer, while a yeast with high attenuation will ferment more of the sugars, leaving a lighter body in the finished beer.

As mentioned earlier, yeast itself can also play a role in the body of the beer. Fresh, green beers served early will still have yeast in suspension, adding to cloudiness but also enhancing the perception of body in the beer.

Perhaps the best commercial example of this is the hefeweizen style from Germany, which is a wheat beer served “with yeast.” This beer is bottled with the yeast sediment, and the server will pour some of the beer off the top and then swirl the bottle around to get the yeast back into suspension before pouring the rest into the glass. The suspended yeast adds considerably to the flavor and body of the finished beer. Another great example is the hazy IPA style, which relies on yeast in suspension, in part, to provide the haze and enhance the body of the finished beer.

Alcohol and Gravity Levels

The warm flavor from high alcohol levels tends to enhance the perception of mouthfeel. A low-gravity light summer or session beer will have less perceived body than a high-alcohol strong ale.

Alcohol in your beer is primarily driven by your starting gravity and choice of yeast, which drives the attenuation. A higher starting gravity beer will drive higher alcohol levels for a given yeast strain. Therefore, raising the starting gravity of your beer is a simple way to also increase the body since a given yeast strain will only ferment a roughly fixed percentage of the sugars.

Selecting a higher attenuating yeast will also drive higher alcohol levels. However, in an interesting twist, higher attenuation also leaves less body in the finished beer in the form of unfermented sugars. If you choose a high attenuation yeast you may get more alcoholic warmth without substantially raising the perception of body since the beer will have less unfermented sugars. So, the entire effect you are trying to create in terms of body, flavor, and balance needs to be considered.

As you drive the alcohol level up to very high levels, overall balance becomes a consideration. First, as you drive gravities and maltiness up, you need to add more hops to achieve the right balance. Second, you really need plenty of body and flavor in a high-gravity beer to offset and balance the alcohol warmth or the alcohol will come across as harsh.

Conversely if you consider non-alcoholic or low-alcohol beers, many of these styles suffer from a lack of body because the alcohol we expect to be in the beer has been removed, throwing the body out of balance. Great lengths often must be taken to add body to a low- or non-alcoholic beer to achieve a normal body and flavor balance.

Tannins

Tannins are found naturally in both grains and hops as well as fruits and even tree bark. They work as a preservative in beer and foods. Tannins are extracted from malt husks during mashing, and extracted from hops in the boil, whirlpool, and dry hopping.

As mentioned earlier, tannins combine with proteins in our saliva causing them to coagulate in your mouth, creating a sensation known as astringency. In moderate doses this reaction can create a perception of additional body. It also creates a dry, crisp mouthfeel, which can be an advantage with certain styles.

However, if you add too many tannins, you can create a harsh flavor akin to sucking on a tea bag. In addition, some people are more sensitive to tannins than others, so excess tannins can be very off-putting to some drinkers.

Tannins from malt are highest in what we call the “harsh zone” malts. Harsh zone malts are malts in the color range of 70–200 Lovibond, including malts near the edge like light chocolate malt and brown malt. If you use malts in this range sparingly, at only a few percent of the total malt bill, you can create great flavor depth as well as additional body. Raising the percentages higher, however, risks creating harsh astringency in the finished beer.

Tannins are also present in hops, so highly hopped IPAs will have more perceived body than a comparable beer with fewer hops. As with malts, over hopping a beer runs the risk of introducing harsh astringency into the beer and often also introduces vegetal off-flavors, so achieving proper balance in a hoppy beer is important. 

Dark Malts

As mentioned in the introduction, dark malts have fewer fermentable sugars, which can be used to drive the finished gravity higher creating additional body. Several studies (cited here) show drops as large as 25% in attenuation when using a high percentage of dark malt (as high as 50% dark malt).

While adding 50% roast malt to a recipe is extreme, the studies mentioned above have shown a consistent relationship between the use of darker malts and lower fermentability. This makes sense as the kilning and roasting process will break down some of the carbohydrates in the malt into a form where they are no longer fermentable and therefore survive fermentation as unfermented residual sugars.

When we combine this lower fermentability with the presence of higher tannins as well as melanoidins (color compounds) from the kilning or roasting process, the overall effect of using dark malts in your beer is to enhance the body of the finished beer. Conversely, lighter-colored beers tend to be perceived as lighter in body.

Conclusion

I’ve provided an array of tools to enhance or reduce the body of your finished beer. The key to using them is often combining several techniques rather than relying on just one. The classic example is Guinness, which includes a high percentage of flaked barley, unmalted stout roast malt that adds a dry coffee-like finish, and a nitrogen and CO₂ stout mix to carbonate the beer. Despite the low alcohol level and low starting gravity, Guinness has a great deal of mouthfeel.

No matter whether you are targeting a full-bodied beer or light summer ale, balance is the key. Going overboard on the use of hops, tannins, alcohol, dark malts, yeast, carbonation, or any single technique will likely result in an unbalanced beer. However, combining several of these techniques in moderation can deliver exactly the body and mouthfeel you want for your next brew. 

Q: Can I put ascorbic acid in my cans before I fill them with beer to scrub any dissolved oxygen? Also, how would I dose it?
— Darren O’Day • Philadelphia, Pennsylvania

Mr. Wizard says…

A: Ascorbic acid, also known as Vitamin C, is indeed an antioxidant often discussed in the context of beer stability because of its ability to scavenge oxygen in the headspace of packaged beer. Its mode of action is somewhat different from many other antioxidants. Ascorbic acid does not directly bind oxygen. Instead, it donates hydrogen atoms to reactive oxygen species such as peroxide radicals, thereby neutralizing them. This transfer of electrons is the fundamental chemical process we call oxidation.

However, the behavior of ascorbic acid can be complicated by the presence of transition metal ions, particularly iron and copper (Fe²⁺ and Cu²⁺). In the presence of these metals, ascorbic acid can actually promote the generation of reactive oxygen species rather than prevent it, effectively reversing its antioxidant role and causing oxidative damage. For this reason, successful use of ascorbic acid requires very low levels of these metal ions. Unfortunately, in brewing, keeping metals out can be difficult. Common brewing inputs such as hops, malt, brewing water, and filtration aids can all be sources of copper and iron. But for the sake of discussion, let’s assume a beer with minimal problematic metal ion content.

When used under the right conditions, ascorbic acid is safe for beer, though flavor limits must be respected. At higher concentrations, it imparts a noticeable tartness. The threshold for this effect varies depending on beer style: Light, delicate beers can show tartness at concentrations above about 10 mg/L, while more flavorful or heavily hopped beers can tolerate slightly higher levels. As is often the case in brewing, bench trials are invaluable for determining the appropriate dosage for a specific recipe. A common working range is 5–10 mg/L.

The most practical way to add ascorbic acid is as an aqueous solution. Because the compound itself is reactive toward oxygen, the solution should be prepared in deoxygenated water — ideally water that has been boiled, cooled, and stored in a sealed container to minimize oxygen pickup.

The dosage calculation is straightforward when using metric measurements. For example, suppose you are working with 20 liters of beer and wish to dose at 10 mg/L. That requires 200 mg of ascorbic acid in total. Since the solubility of ascorbic acid in water at 68 °F (20 °C) is about 330 g/L, there is no risk of creating an overly concentrated stock solution. A convenient approach is to prepare a 40 g/L stock solution. 20 mL of this solution will contain the required 200 mg of ascorbic acid for the 20-L batch. Unless you have a highly accurate scale, mixing up 4 g of ascorbic acid in 100 mL of water is easy to measure and gives you plenty for bench trialing and dosing. 

Q: Two nutrient analytics labs tested my first attempt at a low-carb beer and showed all sugars and carbs as less than 1 g per 100 mL. Yet it does spike my blood sugar severely. According to Brewfather, my recipe should have 3.6 g of carbs per 100 mL. Are the labs missing some type of sugar or carbs?
— Pieter de Weerdt, Via Live Chat

A: This is a great question that affects beer lovers of all sorts, especially those of us who keep a watchful eye on our blood glucose levels. Unfortunately, I cannot provide any specific details about the data you received from the labs who ran your testing with the available information. It does seem unusual that beer with 1 gram of carbs per 100 mL would cause a spike in your blood glucose. As a comparison, commercially produced light/low carb beers brewed in the U.S. contain between 0.7 – 1.9 grams of carbs per 100 mL of beer. Although I cannot provide information about the past, I can comment on differences between expectations and measured values, how to estimate carbs, and a few ways to reduce them in beer. Let’s begin with predictions.

Recipe calculators use predictive equations to estimate alcohol and residual extract based on the original gravity and predicted final gravity. Because malt specifics, mashing particulars, and water chemistry can all affect wort fermentability, predicting final gravity is not much more than a guess. Furthermore, yeast strain, pitching rate, and yeast nutrients influence residual carbohydrates left behind after fermentation. In my experience, making assumptions about fermentation is not as approximate as assumptions about wort composition. That said, predicting final gravity is approximate.

A better way to estimate alcohol and residual carbohydrates is to use a model that uses both original extract/gravity, and apparent extract/gravity. Two estimates I feel comfortable using are the following developed by Gary Spedding because I bumped these calculations against known beer data and they provide solid estimates. Although the original publication in Brewers Digest cannot be found online, this article in Brewers Journal contains Spedding’s calculations. There are two equations in this article for alcohol by weight (ABW) and it is the second that should be used (I converted equations from the original reference into a spreadsheet years ago and know that there was some sort of editorial confusion in the referenced article).

Real Extract = (Original Extract × 0.1948) + (Apparent Extract × 0.8052)

Alcohol by Weight = 0.8052 x (Original Extract-Real Extract) / 2.0665 – (1.0665 x Original Extract / 100)

Here is what the math above reveals about a typical beer-flavored beer with a wort gravity of 11 °Plato and a final gravity of 2 °Plato. Note that I have not included specific gravity equivalents because the equations above use Plato for the calculations, but for those curious we are talking about 1.044 OG and 1.008 FG. Also note that the units on Plato are grams extract per 100 mL of beer or percent by weight.

Real Extract = (11 x 0.1948) + (2 x 0.8052) = 3.74 °Plato

Alcohol by Weight = [0.8052 x (11 – 2)] / [2.0665 – (1.0665 x 2/100)] = 3.5% ABW (g/100 mL)

Alcohol by volume is equal to ABW / 0.79 (the density of ethanol), and 3.5% ABW equals 4.5% ABV. I only show ABV because it is the most common unit used to express alcoholic strength in beer, wine, and spirits. However, when it comes to calculating grams of residual extract and calories, percent by weight is the value to use.

The term real extract is used to define dissolved solids in beer, which are mainly comprised of carbohydrates but also include protein, minerals, and hop acids. For your inquiry, it is safe to assume that 100% of the real extract can be attributed to carbs because that slightly overestimates the value.

We have determined that beer with an OG of 11 °Plato and a final gravity of 2 °Plato contains 3.7 grams of carbs per 100 mL of beer and 3.5% ABW. Carbs contain 4 kcal/gram and alcohol contains 7 kcal/g, giving the beer in this example 39.3 kcal/100 mL of beer or 140 kcal per 12-oz. (355-mL) serving.

In my experience, a lab analysis should provide data that is similar to what is calculated above provided you are producing beer that falls into the typical range of beers found in the market. Spedding’s calculations are based on beer data and do not work for completely fermentable solutions. Without knowing the original extract and apparent extract of your beer, I don’t know if the Brewfather prediction is off or if the labs are off. Run the numbers to see which set of data seems most plausible.

I am guessing from your question you may use a continuous blood glucose monitor. I use one of these devices and have learned a lot about how different foods and beers affect my blood glucose. I feel fortunate to have discovered that my blood glucose was abnormally high a few years ago and to be successfully controlling things with a combination of diet, medication, and monitoring. One thing I learned is my body reacts differently to some beers. When I drink non-alcoholic beers produced using maltose-negative yeast strains, for example, my blood glucose usually spikes because these beers contain all of the maltose and maltotriose that comes with mashing. I also have noted spikes when drinking “normal” beers that have above average final gravities. One hunch that I have with some of these beers is that they have been fermented with yeast strains that do not ferment maltotriose. Unfortunately, this property of yeast strains is not widely published. It is known, however, that many English strains popular among the haze-crazed crowd do not ferment maltotriose.

Methods to lower carbs in beer include extended mash rests in the 140–145 °F (60–63 °C) range, the use of exogenous alpha amylase or amyloglucosidase in the mash or fermenter, substituting sucrose or dextrose/glucose for a portion of malt or malt extract to increase wort fermentability, brewing lower gravity beer styles, selecting high-attenuating yeast strains, and taking advantage of hop creep to dry beers out. 

Hydrometers are simple devices that rely on a precise weight to measure the density of the solution it’s floating it. In a solution of pure (distilled) water, weight in a brewer’s hydrometer allows the tool to float to a determined marking labeled as 1.000 specific gravity (SG) or 0 °Plato at either 60 °F (16 °C) or 68 °F (20 °C). (Homebrewers prefers specific gravity while professional brewers prefer the Plato scale.) Hydrometers are great for either original gravity (OG) or finishing gravity (FG). Learn how to use a hydrometer and also how to calibrate it so you can trust the results in this video.