Ever wonder what it takes to make one bar of chocolate? ICE Creative Director Michael Laiskonis, our resident chocolate expert, takes us through the entire process — from sourcing and roasting, to refining and conching, to finally molding and tasting — in less than a minute. But don’t be fooled by the video: though it may seem like a piece of (chocolate) cake, careful thought and calculation goes into each stage. According to Chef Michael, “Every step of the chocolate-making process, from fruit to bean to bar, presents an opportunity to influence the flavor and texture of the finished chocolate.”

Sweet tooth piqued? Discover how you can become a pastry pro with ICE’s award-winning career training programs by clicking here

It’s hard to believe that it’s been two years since we launched ICE’s bean-to-bar Chocolate Lab (the first education-focused one of its kind!). We decided to check in with ICE’s Creative Director Michael Laiskonis to find out what he’s been up to. As it turns out: a lot.

Having produced over 120 batches of chocolate with beans sourced from more than 20 countries, the Chocolate Lab has given Chef Michael the chance to tinker with each step of the chocolate-making process and bring out the best qualities in each bean. What’s more, Chef Michael has been meticulously tracking these changes and differences in process and flavor, which he then shares with interested students and colleagues in a number of hands-on classes at ICE.

Our Pastry & Baking Arts students have also had the opportunity to swap textbooks for hands-on experience with Chef Michael inside the Chocolate Lab, benefitting from a full understanding of the bean-to-bar process.. Watch below our two-year check in with Chef Michael.

Want to study in the ICE Chocolate Lab with Chef Michael? Click here for more information on ICE’s Pastry & Baking Arts program.


By Michael Laiskonis—ICE Creative Director

The final steps in processing our bean-to-bar chocolate make up the longest phase of the manufacturing process—a waiting game where the true essence of the bean, its complex flavor and its silky texture are unlocked. At this point, we focus on physically breaking the bean’s coarse texture, revealing subtleties beneath its bitter astringency and liberating its cocoa butter. Though we add ingredients at this stage, there is also an aspect of elimination—the refining stage is followed by conching, which peels away unwanted volatile flavors.

Sifting the Finished Chocolate

My last post dealt with handling the roasted bean—crushing it into nibs, separating its shell, grinding it into fluid cocoa liquor and extracting pure cocoa butter. During this final stage, the chocolate maker faces the challenge of tasting a bean’s full potential and identifying the subtle nuances within. While the goal of the “craft” chocolate maker working primarily in single origin batches is often to enable the expression of that bean’s inner essence, an industrial manufacturer’s typical aim is to create consistency from batch to batch, from year to year. Neither approach is qualitatively better or more difficult—just two possible approaches employed in the final stage of chocolate making.

Refining

Different kinds of machines can carry out the task of refining (stone melangeurs, roller refiners, scraped-surface refiners, etc.). In the lab, our coarse chocolate liquor enters a 10-kilogram capacity ball mill—a temperature-controlled tank that contains roughly 60 pounds of hardened steel-grinding media (ball bearings, essentially, in two sizes). With agitation, the steel balls begin breaking down the fairly large particles in the liquor, refining them down to a target of around 20 microns—in terms of scale, one micron (µm) is one-millionth of a meter (or one-thousandth of a millimeter). More accurately, true particle size in chocolate will lie along a curve, or a distribution, some smaller and some larger than our target. Looking closely at the structure of chocolate, it is simply very small solid particles (cocoa solids, sugar and sometimes milk solids) dispersed in fat—cocoa butter. Because the threshold of perception of a particle on our palate is in the neighborhood of about 35µm, a smooth, creamy mouthfeel depends upon breaking down the solids below that mark. Particles that are too small (below 15µm), however, will create too much surface area for the available cocoa butter, thus adversely affecting the flow properties of the chocolate with increased viscosity.

Most often, we add our ground liquor to the ball mill to refine for some time before adding any other ingredients. As the liquor continues to break down, more of its cocoa butter is released, providing sufficient fluidity to begin processing additional dry ingredients, namely sugar and, in the case of milk chocolate, whole milk powder. Virtually all of our chocolate receives an additional boost of cocoa butter as well. Vanilla, a common but not compulsory addition, can enter into the mix in various forms. I typically chop up whole vanilla beans and add them early in the refining process. Though the majority of the dozens of batches created in the lab have been of single origin, I have begun working on blending beans, and even introducing additional flavors—whole coffee beans, spices and nuts—to thoroughly integrate into the finished product. For our first attempt at a vegan milk chocolate, I replaced conventional milk powder with freeze-dried coconut milk. Refining time can vary, depending upon the batch size, particle size of the liquor and by agitation speed.

Measuring Particle Size on a Grind Gauge

measuring particle size on a grind gauge

Conching

Ball Mill

the ball mill

In addition to speed control, our ball mill also offers temperature control and heated airflow. Lacking a stand-alone conching machine, this heat and airflow help us replicate some of the effects of traditional conching. In basic terms, the conching phase is best described as heated agitation. Three key aspects of conching are moisture reduction, texture and flow enhancement and development of flavor. Residual moisture in chocolate can affect its flow properties, even though a great deal of the raw bean’s water was removed during the roast, trace amounts remain through the grinding and refining process. Prolonged mixing also helps ensure that all of the tiny solid particles are evenly dispersed in and coated by the cocoa butter, which improves mouthfeel and workability. And finally, the heat and forced air aid in driving off some of the remaining volatile acids – unwanted flavors that are a byproduct of fermentation back at the bean’s origin. Conching is an important part of the process, but each chocolate will require varying amounts. Long a marketing myth in the chocolate industry, a longer conching time does not necessarily equal higher quality. Some argue that excess conching may even destroy desirable flavors.

Once the chocolate is deemed ‘finished,’ it is extracted from the ball mill (we also employ two small stone grinders for smaller experimental test batches) and passed through a vibrating sifter—imagine a super-fine mesh strainer—which catches any particles not sufficiently refined. The radicle, the hard and bitter germ stem in every cocoa bean, may stubbornly evade grinding, along with the occasional bit of vanilla bean that sticks to the agitator. After sifting, it’s time for tempering and molding, right? Well, not so fast. Aging chocolate for a period of time, though unpredictable and not fully understood, is common practice. Some chocolate makers prefer to temper, mold and package chocolate immediately, others will age chocolate from two weeks to one month. Though there may be little one can do to change the finished product at that point, most believe that the true character of the chocolate will not reveal itself until it has had a minimum three-week mellowing period. One of the ongoing projects here in the lab is to hold back portions of each batch to sample at regular intervals to track some of these still-inexplicable changes over time.

As with other stages of the chocolate making process, success during refining relies on equal parts science, experience, taste, patience and arguably, some degree of intuition. The key is understanding that each part of the process presents a new set of variables. The next dispatch in this series will address formulation— the recipe development phase for each batch of chocolate.

Aging Chocolate

aging chocolate

Want to dive into the chocolate lab with Chef Michael? Click here for a list of his upcoming workshops at ICE.

 

By Michael Laiskonis—Creative Director

Every step of the chocolate-making process, from fruit to bean to bar, presents an opportunity to influence the flavor and texture of the finished chocolate. After harvesting, fermenting and drying at origin, beans are shipped around the world. Once received at the factory, raw cocoa undergoes several steps of transformation—what we call the “bean-to-bar” process. Previously I’ve discussed the bean-to-bar steps of sourcing and roasting. In this post, we will look at the intermediate steps necessary to turn flavorful roasted beans into the refined product we know and enjoy.

The nuanced flavors and smooth texture we associate with chocolate evolved during the Industrial Revolution, alongside the general advancement of technology and mechanization in the mid to late 19th century. This rise of the machine, so to speak, not only made chocolate products readily available to the masses, but it also catapulted what was a coarse bar or a rustic beverage to more sophisticated heights. Key players responsible for the machines and processes developed during this time remain some of the most recognized names in contemporary chocolate production today, including Van Houten, Peters, Nestlé and Lindt.

Machinery remains a constant in the contemporary chocolate-making process, and many visitors to the ICE Chocolate Lab are surprised by the sheer number and diversity of machines we employ. Below, I’ll explain the three processing steps, and their dedicated machines, that bridge the gap between roasting and refining.

Each bean has an outer shell, the germ stem (or radicle) and the nib, the latter of which contains a fat content of roughly 50-55%. Once out of the roaster and cooled, we must first break the bean and remove its shell. The removal of the shell is important for flavor, texture and food safety reasons: too much shell in our finished chocolate can produce a musty flavor and gritty texture and excessive wear and tear on our equipment. Additionally, while we have rendered the beans safe to handle from a microbial perspective by roasting, the high levels of heavy metals harbored in the shell are reason enough to discard them. In short, the shells do not positively impact flavor and are not considered “wholesome.”

cacao beans raw chocolate bean to bar chocolate

To remove the shells, we employ a winnowing machine, which yields only the nib, roughly 85% of its original weight, for further processing. We load the whole roasted beans into a hopper that funnels them through a rotating gear, crushing the bean and separating nibs from their shells, which have already loosened during the roasting phase. The fractured pieces then fall through a series of vibrating screens, causing the bits of nibs and shell to “dance” their way toward a vacuum which will suck the lighter shell from the screen while allowing the heavier nibs to pass through untouched. Our goal is to minimize the amount of shell in our nibs, while preventing any nibs from inadvertently getting discarded, so constant adjustment of the winnowing machine is necessary. We can control the rate of breaking the beans, the flow of particles along the screens and the intensity of the vacuum. Because shell weight can vary from bean to bean, we constantly monitor the nibs as they fall into a collection bin. From unsorted raw bean to cleaned nibs, it is not uncommon to lose 20-25% of our original weight of product.

Freed from their shells, the nibs then begin an intermediate grinding phase. Any number of grinding methods can perform this function, but in our lab we pass the nibs through a rotating hammer mill, which impacts the nibs at high speed, forcing them through three progressively smaller screens. The result is a coarse, semi-liquid paste that we refer to as chocolate “liquor”—confusing, as there is no alcohol present. This liquor is a suspension of dry cocoa solids, which vary in size up to a few hundred microns, in cocoa butter that is liberated from the nib and liquefied due to the heat of friction created during grinding. Each pass through the mill both saves time and reduces wear on the next stage of refining equipment. The final pass also often allows us the opportunity to isolate and remove a good deal of the hard, bitter radicles, which can contribute a harsh flavor and gritty texture to finished chocolate. Leaving the hammer mill, the liquor then enters a ball mill, along with any additional ingredients—at a minimum, sugar and additional cocoa butter—to achieve a final particle size near 20 microns.

micrometer chocolate mashup

The ability to press the added cocoa butter in the ball mill stage ourselves is one of the most exciting aspects of our production in the ICE Chocolate Lab. Up to two kilograms of our ground liquor is loaded into a heated pot and secured onto a hydraulic press. Gradually ramping up pressure over an hour or two—topping out at some 65 tons—will yield between 40-45% cocoa butter, which, unlike commercial deodorizer butter, emerges with significant flavor and aroma intact. This supplemental fat is used to boost the final cocoa butter content of the finished product, which for couverture-grade chocolate lies between 35-40%, maximizing fluidity and mouthfeel.

The machines we employ during these intermediary steps between roasting and refining typify how advancements in technology have helped make chocolate production more efficient and consistent. The next installment in this blog series will pick up with formulation, refining and conching—the final steps in which the chocolate maker can influence the finished product’s complex characteristics.

Interested in learning about chocolate firsthand? Click here for a list of upcoming classes with Chef Michael in the ICE Chocolate Lab.

 

Under the leadership of Creative Director Michael Laiskonis, every day in ICE’s Chocolate Lab is an opportunity for research and experimentation. Step inside the lab as we unwrap the chocolate-making process—from bean to bar—and discover just what it takes to create this beloved treat.

To discover the craft of bean-to-bar chocolate for yourself, request free information about ICE’s professional Pastry & Baking Arts program and continuing education courses for current pastry chefs.

 

By Michael Laiskonis—Creative Director

Previously harvested, fermented and dried at origin, cocoa beans arrive at ICE’s Chocolate Lab ready to transform from raw bean to finished chocolate bar through cleaning, roasting, winnowing, milling, refining, conching and tempering. There is no specific formula to determine optimum roasting time and temperature across the board: beans of different size, variety and origin require a unique roasting profile to achieve the desired end results. It is at this stage where the manufacturer begins to place an individual stamp on the finished product.chocolate bean cacao bean size bean to bar chocolateBefore the beans are loaded into the roaster, they must be cleaned and sorted. While this involves sifting out dust and broken beans, we are also on the lookout for flat beans (essentially all shell and no nib), germinated beans (easy to spot by the perfectly round hole on the end of a bean) or any part of the pod that isn’t a bean. Anything other than a sound bean will do us no favors in the flavor of the finished product. Novice chocolatiers are often surprised by how much non-cacao debris is found: from sticks and stones to pieces of the burlap sack that the beans arrive in. In chocolate-making circles, one hears of all kinds of sorting table discoveries—some I chalk up to urban legend—but I’ll just leave those possibilities to your imagination!

In general, the chocolate roasting process is similar to that of coffee, except coffee needs fast, high-temperature roasts, while cacao should be handled gently, with a lower and slower treatment. Typical cacao roasting temperatures range from 250-275°F up to 350°F, with the roasting process lasting between 30-90 minutes. Other variables—such as a cold or hot start and temperature adjustments during the process—are influenced by the inherent characteristics of the beans and the particular style of the manufacturer.

Many chocolatiers believe that Forastero-type beans are more amenable to a deep roast, while more subtly nuanced Criollo beans need a lighter roast. Regional differences can also influence roasting style. For example, a bean from Madagascar, known for its bright fruitiness, may need a longer roast to rid it of excess acidity, yet not such a deep roast that those desired fruity notes are driven off. My first test batch of Madagascar beans was a nail-biter, I had to observe the roast carefully to find the perfect “sweet spot.” In the end, the roasted nibs had a complex flavor—not too acidic, but with an interesting hint of citrus and passion fruit that carried through to the finished bar!cacao beans raw chocolate bean to bar chocolateRoasting equipment can vary—from massive, old school ball roasters to converted coffee roasters, to low-tech solutions such as roasting thin layers of beans on sheet pans in standard convection ovens. With large-scale manufacturing, producers may forgo whole beans and apply the roasting process to cracked and winnowed beans (nibs) or even to the milled liquor itself. In ICE’s lab, we utilize a drum roaster—small by most standards—with a capacity of about 15K (35 pounds). No matter the method, the key to proper roasting is even transfer of heat and adequate airflow.

During the roast, ICE’s lab and adjoining hallway are filled with an intense aroma similar to freshly baked brownies. While we use some subjective measures like taste and smell, our drum roaster also allows us to determine the depth of roast by way of bean mass temperature: a thermocouple probe is buried within the tumbling mass of beans, giving us some degree of quantifiable flavor data. Although we may, for example, set the roaster to 300°F, I will often pull the beans once they’ve reached a mass temperature of anywhere between 245-275°F. Even before that, I will sample beans for tasting, around an internal mass temperature of 235-240°F. It is fascinating to witness flavor transformation within a narrow difference of just five to 10 degrees.Roasting Winnowing Chocolate Production Bean to BarSo what is really happening during the roasting process? Heat treatment renders the beans safe to consume, destroying harmful bacteria and mycotoxins. I often tell students that raw cocoa beans should be treated like raw meat in terms of their bacterial risks. Roasting also rids the beans of moisture and certain volatile acids: out of the bag, dried beans contain roughly 7% water, and it is common to lose four to five percent of the bean weight to water loss during roasting. Roasting will also loosen the shell of the bean, which helps facilitate the winnowing process later on. Most importantly, all of the complex chemical reactions (Maillard reactions and Strecker degradation) take place during roasting, transforming the flavor precursors created during fermentation into hundreds of individual compounds that give chocolate its alluring color and taste.

As with most foods—like a steak or a loaf of bread—the cooking process continues even after we’ve removed the beans from their heat source. Put simply, cocoa beans, if not quickly cooled, will continue to roast after leaving the roaster. When we reach our optimal profile (experienced roasters aim for the point just before this to allow for “carry over” cooking), the beans are dumped onto a cooling cart, where a vacuum draws air through the beans to expedite the cooling process.Test Roasting Cocoa Bean SamplesRoasting is a crucial component to the flavor of chocolate and the first opportunity for the chocolate maker to infuse their individual approach. Assessing the beans and knowing which of their qualities to enhance is a skill gained from experience and intuition. An important part of our work in the ICE Chocolate Lab is the documentation of every measurable part of the process. With every batch of beans, I plot out detailed roasting curves, logging bean and roaster temperatures every few minutes. Not only do these efforts help correlate temperature with flavor, but they are an important step towards the ability to produce multiple batches with some degree of consistency.

Eager to study in ICE’s Chocolate Lab? Click here for upcoming classes.

 

Over the past 10 years, the number of bean-to-bar chocolate operations in the United States has grown exponentially. Yet no American culinary school has invested in a chocolate lab where pastry students and seasoned professionals can experience the full cycle of bean-to-bar production…until now.

ICE’s Chocolate Lab was designed to expose students to the premier small-batch equipment in the industry—the very same tools used by some of the world’s leading research and development chefs and chocolatiers. Our partner in this groundbreaking venture is Cacao Cucina; the only American company that specializes in the production of artisanal, bean-to-bar chocolate equipment. The lab is also outfitted with premier chocolate moulding, tempering and finishing equipment from Tomric Systems.

“I once read an article where a chocolatier stated, ‘The most important step in making chocolate is every step.’ With the development of this center of research and development, I’m excited to show pastry chefs who aren’t chocolate makers how quantitative aspects of the process—roasting time and temperature, milling particle size, etc.—can effect the end flavor, and to explore the best applications of every type of chocolate.” – Michael Laiskonis, ICE Creative Director

To learn more about the Chocolate Lab at ICE, click here.


By
Michael Laiskonis—Creative Director

What’s the latest news from Brookfield Place? The Chocolate Lab at ICE’s new facility is fully operational, and chocolate making on our bean-to-bar Cacao Cucina equipment has begun in earnest. Batches both large and small are ready for tasting, featuring beans from a wide range of origins, including the Dominican Republic, Ecuador, Trinidad and the Ivory Coast. And after many a dark chocolate batch, our first milk chocolate just rolled off the assembly line – with a heady 50% cocoa solids.

As we gear up for increased production and the first of our bean-to-bar classes this fall, I’ve compiled some surprising facts about the different stages of the chocolate making process. These observations may be old hat to professional chocolate makers, but they are rarely—if ever—considered by chefs and consumers.

Raw Chocolate Sorting Beans Chocolate Lab Bean to Bar

Raw Beans
Straight out of the bag, fermented and dried beans present a serious microbiological risk, including E. coli and salmonella. Outbreaks linked to chocolate are rare, but the risk necessitates proper handling and storage. Simply put, I treat raw beans as if they were raw meat. Also, raw beans must be carefully sorted and cleaned of the various debris found in each bag (flat and moldy beans, stones, leaves, sticks, etc.). If that’s not enough, it isn’t uncommon for tropical moth eggs to hitch a ride on the surface of a cocoa bean! All of the beans that arrive at ICE’s lab are immediately bagged, sealed and chilled until roasting—before any of those tiny wings get an opportunity to hatch.

Roasting
In addition to providing the only bacteria and moth “kill step” that renders the beans safe to consume, roasting allows for critical flavor development of the cocoa bean, further developing the precursors created during fermentation. Roasting also reduces the moisture content of the dried bean (chocolatiers always seek to minimize the amount of water in finished chocolate), which upon delivery is around 6-8%. Roasting parameters vary by bean type, origin, quantity and the desired flavor profiles—but typically roasters aim for 30-60 minutes or more at temperatures in the range of 300-350°F. Determining “doneness” is mostly subjective and instinctive. Chocolatiers primarily go by smell and taste, but also closely monitor the temperature of the bean mass throughout the process.

Winnowing
After roasting, the beans must be cracked and winnowed, separating the nibs from the shell. The shell alone can account for almost 15% of the roasted bean by weight and adversely affects the flavor and texture of finished chocolate. What’s more, the shell contains elevated levels of toxic heavy metals. Unsurprisingly, the acceptable industry standard for shell content in processed nibs is less than 1%.

Roasting Winnowing Chocolate Production Bean to Bar

Roasting beans and winnowed cocoa nibs

Grinding
In most cocoa processing systems a “pre-grinding” of the nibs is necessary, to reduce both overall processing time and the eventual wear on refining machines. After grinding, the nibs are reduced to a thick paste referred to as “chocolate liquor,” with a mean particle size around 100 microns. (And yes, the term “liquor” is confusing to many, as there is no actual alcohol involved!)

Pressing Cocoa Butter
A portion of the liquor can be pressed to produce cocoa butter, which makes up roughly 50% of the beans’ weight. In the lab, this process takes one to two hours and nearly 65 tons of force. The remaining byproduct—known as “press cake”—can be further processed into cocoa powder.

Unlike the deodorized cocoa butter most chefs are familiar with, freshly pressed butter reflects the flavor compounds from the original beans. As most fine chocolate has a total fat content of 35-40% by weight, this additional cocoa butter can be added to boost the final percentage. For some single origin enthusiasts, this added butter makes or breaks a product’s bean-to-bar status, depending on whether or not the extra butter and original liquor are extracted from the same batch of beans.

Refining
Refining reduces the particle size of the liquor to an average of 20 microns. The human tongue can begin to detect grittiness at particle sizes larger than 35 microns, but reducing particle size below 20 microns increases the surface area of the cocoa butter, resulting in an unpleasantly thick consistency.

Refining is also the point in the bean-to-bar process at which other ingredients are introduced—sugar, additional cocoa butter, whole milk powder, etc. This process is achieved by an array of different machines, from stone melangeurs to roller refiners. Some systems, like our ball mill, work as a “universal,” allowing for “conching” to occur simultaneously with refining, due to the addition of temperature and airflow control.

Cocoa Butter Sifting Chocolate Refining Bean to Bar

Freshly pressed cocoa butter and sifting chocolate liquor

Conching
Conching—which involves heat, airflow and agitation—is critical for flavor development (removing unwanted volatile compounds), texture (coating the solid particles with cocoa butter) and further moisture reduction. This process can last for hours or days, depending on the desired results. However, conching time alone is not necessarily a measure of quality.

Formulation
The final “recipe” for a batch of chocolate is determined by the addition of other ingredients, and will vary depending on such factors as bean type, desired flavor profile and application. The percentage you see on the label of finished chocolate refers to the total amount of cocoa solids by weight—meaning the nibs or liquor plus any added cocoa butter. This number alone is quantitative, not qualitative—a 70% chocolate may be 70% nibs or any equivalent combination of nibs and cocoa butter. Therefore, these percentages may not offer much insight into flavor, but they can tell us how much sugar was added. The percentage of sugar simply equals 100 minus the cocoa percentage (accounting for less than 1% additional vanilla or stabilizers like lecithin, etc.).

Sifting
Before tempering, it is beneficial to sift or strain the finished chocolate through vibrating screens to remove any large particles that are difficult to refine—notably the “radicle” (or germ stem) that is a part of each bean. This hard stem is very bitter and can produce a gritty texture if left in the chocolate. Integrating a pass by powerful magnets into the sifting process can also eliminate the worry of any remaining hard metals in the chocolate.

Finished Chocolate Bean to Bar Aging

Aging
While the aging process is not well understood or widely researched, both large manufacturers and small-batch artisans agree that several weeks of aging finished chocolate allows for better, rounder flavor. Large companies inherently allow for this process in their distribution network, while artisan producers will hold chocolate batches in reserve for two months or more before tempering, molding and packaging. None of our batches is more than three or four weeks old at this point, but I’m eager to experience the aging process for myself. I’m reserving most of each batch to evaluate the effects of aging, but with so many of our students and staff eager for a taste, I’m also already molding small quantities for the instant gratification of our efforts!

Can’t wait to check out ICE’s Chocolate Lab? Sign up for bean-to-bar classes with Chef Michael.