Candi Sugars & Syrups
Caramelization is overstated in both brewing and cooking because it requires exceptionally high temperatures. The far more common non-enzymatic browning process is the Maillard reaction. Despite the names, caramel candies made with dairy and caramel malts are primarily flavored and colored by Maillard reaction products formed by the complex interactions of reducing sugars and amino acids, when exposed to moderate heat.
The Maillard reaction is more complex than caramelization because it requires the interaction of multiple molecules. The compounds created include the flavors we associate with such common brewing ingredients and techniques as Munich malt, decoctions, kettle “caramelization,” coffee beans, maple syrup, and Belgian candi sugar. While malt typically contributes most beer’s Maillard reaction products, this article focuses on areas where the brewer has control.
The Sciency Bit
The crucial difference, elementally-speaking, between caramelization and the Maillard reaction is the addition of nitrogen. Nitrogen is one of the fundamental ingredients to life, being essential to such biological greatest hits as DNA and protein. The sulfur found in some amino acids gets involved too. Pure sugars (e.g., glucose and sucrose) contain only carbon, oxygen, and hydrogen; refining removes all of the amino acids from the source corn, sugar cane, or beets.
With only one exception, heat in excess of 320 °F (160 °C) is required to caramelize sugar molecules into the characteristic multitude of acids, bitter compounds, and aromatic molecules. Fructose is the exception and will begin to caramelize around 230 °F (110 °C). While caramel syrups do have a historic home in English brewing, they can impart harsh flavors and are difficult to make at home because achieving 320 °F (160 °C) requires a syrup with less than 2% water. The addition of amino acids allows the Maillard reaction to occur even at room temperature (although sluggishly), explaining why liquid malt extract darkens during storage.
Louis Camille Maillard described his eponymous reaction in the early 20th century. I’d say discovered, but cooks, bakers, and brewers had known for millennia that roasting meat, baking bread, and kilning malt creates delicious flavors and aromas not found in the raw ingredients. The result is a variety of melanoidins (flavorless, brown polymers), pyrazines (chocolate, potato), oxazoles (floral), and peptides (savory). While there has been some research into which amino acids and sugars increase production of certain aromatic molecules, there are hundreds of distinct compounds created by this still not entirely understood, multi-stage reaction.
Alkaline conditions up to around a pH of 10 increase the rate of the Maillard reaction, which is why sourdough bread is often so pale. Sugars with a free aldehyde or ketone group, called reducing sugars (e.g., glucose, fructose, and maltose), are required. Sucrose is not a reducing sugar because the component fructose and glucose are linked at their reducing ends. However, they can be split (i.e., inverted) by moisture, heat, and time, especially in an acidic environment.
Candi Syrup
Belgian-style dark candi syrup plays an essential role in the rich fruity flavors of dubbels and quadruples. Starting with unrefined sugar beet syrup, producers add alkaline ingredients and cook the syrup. While delicious commercial dark candi syrups are available, making your own is inexpensive, requires no special equipment, and allows customization.
On his blog Ryan Brews (http://ryanbrews.blogspot.com/), Ryan Ekre posted details on how boil time and various additions change the flavors produced in homemade candi syrup. Starting with table sugar, pickling/slaked lime (to raise the pH), Wyeast Wine Nutrient Blend (to replace the amino acids contained in sugar beet syrup), and water, he boiled for 15 minutes resulting in “Tootsie Roll” chocolate aromatics. Extending the boil to 40 minutes changed it to “Toffee and dark fruits,” without adding the bitter/acrid flavors you’d associate with nearly black caramel. My technique to make candi syrup in the sidebar on the left of this page is based on Ryan’s.
Ronald Pattinson’s The Home Brewer’s Guide to Vintage Beer includes instructions for making English-style caramel syrups. He calls for adding a small amount of citric acid to invert the sucrose, and holding at a temperature of 240–250 °F (116–121 °C) for up to five hours to allow the fructose to caramelize. Ron points out that these syrups are the only brewing ingredient (unlike hops, malt, and yeast) that we have any hope of recreating accurately for historic recipes!
Maple Syrup
Few recent brewing trends have gotten beer nerds salivating like maple stouts. The sap that flows out of tapped sugar maples in early spring is watery, 3% sucrose at best. Boiling (sometimes preceded by reverse osmosis) not only evaporates water, concentrating the sap’s lightly woodsy flavor, vanillin, sugars (to 65%), and proteins, but also produces Maillard reaction products. The darker grades are a result of more melanoidins and consequently other flavorful Maillard products. As a result, darker grades are preferred for brewing.
Many brewers swear by adding maple syrup as late in the process as possible, after primary fermentation slows, even to kegged beer to prevent refermentation. However, others advocate adding it at the start of the boil, allowing more time for the Maillard reaction. Don’t worry about boiling-off the aromatics of the maple syrup, given that they were created by boiling in the first place! However, the carbon dioxide released during primary fermentation may scrub some delicate aromatics. In my experience it takes a large amount of maple syrup, 5-10% of the batch by volume, to impart an assertive maple contribution through the roasted grains in a stout.
Maillard Wort
Malted grains contain sugar and amino acids, so malts contain Maillard products from kilning/roasting, but we can create more during brewing. For lagers this is traditionally accomplished by decocting the mash, with longer boiling steps for darker beers. However, decoctions need babysitting to avoid scorching and don’t get hot enough to produce assertive flavors. If your goal is intense Maillard reaction contributions, the more suitable stage is the boil.
Simply sparging longer to dilute the wort and extending the boil from 60 to 120 minutes will result in only a subtle increase in Maillard products because it doesn’t increase pH, sugar concentration, or temperature. The two most effective ways to concentrate the sugars and consequently raise the boiling point are to make a syrup from the first runnings, or concentrate all of the wort to a high density with a lengthy boil.
To make a wort syrup, collect first runnings equal to 20% of the batch size in a separate kettle. Boil until it looks like malt extract (about 1⁄5 of the original volume, or gravity ~1.300). Stir frequently as the bubbles stack, indicating that little water remains. Add the syrup to the main boil at flame-out.
The concentrated boil technique, which I adapted from Alan Sprints of Hair of the Dog Brewing Co. (Portland, Oregon), is to under-collect the amount of wort and then concentrate below the target post-boil volume. For example for a 5-gallon (19-L) batch, collect 5.5–6 gallons (21–23 L) and boil for three or more hours to yield 2.5–3 gallons (9.5–11 L) of wort. Dilute to the target volume with water post-boil. Because you collect comparatively little wort, your efficiency will suffer (which is one reason Hair of the Dog brews a variety of second runnings “Little Dog” beers). It is similar to the process used by many extract brewers, which explains so many copper-hued pale ales from new brewers!
Both techniques are especially beneficial for creating simple recipes for wee heavy, barleywine, and doppelbock, replacing or better yet enhancing the contributions from caramel malts. They generate flavors that aren’t available in commercial malt or sugar syrup. However, Maillard reaction can be overdone and may not be beneficial for a beer with a substantial amount of Munich, aromatic, or melanoidin malt.
Maillard reactions happen during brewing whether you are aware of them or not, but understanding how to manipulate them is another arrow for the brewer’s quiver.
Homemade Candi Syrup
Starting Point:
Basic: 1 cup (250 mL) of sucrose, 1/4 cup (60 mL) water, ½ tsp. (2.5 mL) Wyeast Brewer’s Choice Nutrient for Beer, and 1/2 tsp. (2.5 mL) pickling/slaked lime (if you don’t detect a waft of ammonia when the boil begins, add a little more pickling/slaked lime mixed with water).
For toastier, breadier flavors, make the basic recipe and add 1 tsp. (5 mL) light dried malt extract.
For a wider range of interesting chocolaty and dark fruit flavors, make the basic recipe and add 1 tsp. (5 mL) treacle.
Consider using unrefined sugars (e.g., date, palm, honey, maple syrup) or sources of amino acids (e.g., milk powder, other yeast nutrients).
Step by step
1. Mix all ingredients in a 2–3 quart (2–3 L) sauce pan. To prevent scorching, select a pan made of highly conductive metal.
2. Heat over medium-low. Once the sugar is dissolved adjust the heat to maintain a slow simmer. Place the lid on for the first three minutes to allow steam to dissolve sugar crystals on the sides.
3. Remove the lid. Do not stir after this point because agitation can cause sucrose to crystalize. If this happens, add water to dissolve. You can replace 1 tablespoon (15 mL) of the sucrose with corn syrup to reduce this risk.
4. When the color starts to darken around 260 °F (127 °C), re-apply the lid to slow evaporation. Add 2 tablespoons (30 mL) of water if the syrup rises above 300 °F (149 °C) to prevent caramelization.
5. Remove a small amount of the sugar every five minutes and take tasting notes.
6. Once you determine your ideal recipe, scale up or repeat. When the flavor reaches your desired point, add 1⁄3 cup (80 mL) of water to halt cooking and prevent the syrup from solidifying as it cools.
Inverting the sucrose by boiling for 20 minutes with ½ tsp (2.5 mL) of cream of tartar or using the enzyme invertase before adding the yeast nutrient and slaked lime will cut 15 to 20 minutes off the cooking time. Starting with dextrose (sold as priming sugar) accomplishes the same thing. In both cases I did not find that starting with reducing sugars improved the flavor. Substituting lactose produces a mellow toasty syrup, but crystallizes quickly while cooking.
Sources
1. On Food and Cooking, Harold McGee.
2. Ryan Brews Candy Syrup the Right Way (Hint – We’ve Been Doing it Wrong!): http://ryanbrews.blogspot.com/2012/02/candy-syrup-right-way-hint-weve-been.html
3. “Origin of carbons in sulfur-containing aroma compounds from the Maillard reaction of xylose, cysteine and
thiamine.” LWT – Food Science and Technology Volume 40, Issue 8, October 2007, Pages 1309–1315
As this picture illustrates, boil times (listed on the left in minutes) and various additions change the color, as well as flavor, of the candi syrup. The column on the left shows samples of the basic candi syrup recipe with the addition of dried malt extract; the center column is just the basic recipe; the column on the right is the basic recipe with treacle added.
