- I've been challenged to produce the ultimate Hamburger Bun...
- Counter Top Deep Fryer Recommendations
- Country Gravy
- The benefit of understanding the Baker's Percentage system...
- Recover every last drop of beef stock...
- Experimenting with reducing the amount of starter used...
- [Washington Post] Scientists figure out what makes Indian food so delicious
- Pressure cooker beans
- Fried Rice (Chinese style)
How To Julienne An Onion
Start by topping and tailing the onion and peeling off the outer skin.
Starting on the same side of the onion as your knife hand, make thin, slightly angled cuts towards the center of the onion, using proper guide hand technique to make sure your cuts are uniform, thin and accurate.
Once your knife reaches a 90° angle (halfway through the onion), roll the onion on its side and continue as before.
|This post is part of our ongoing Culinary Knife Skills Video Series, which teaches you a wide array of knife skills used in professional kitchens. For more information, you can also view our How To Cook Video Index.|
Cooking at altitude can be intimidating for the uninitiated, but once you understand the basic underlying science, you'll never need another high altitude cook book again.
HIGH ALTITUDE BAKING AND COOKING VIDEO LECTURE: PART ONE
As most of you are already aware, cooking at altitude will effect the food you're preparing, sometimes causing undesirable results. Food items that heavily rely on water's boiling point, such as pasta, potatoes, and braising meat, will simply take longer to cook since the boiling point of water is reduced at altitude. Cakes, breads, and pastries also have a tendency to dry out, crack, and deflate starting at around 3,000 feet (914 meters).
To understand why this happens, you must first grasp the science behind water. When you stop to think for a moment, a lot of cooking has to do with controlling water in its various states. Since most items you cook contain water, or will require a water based cooking method, understanding how water acts at altitude is the first step to mastering high altitude cooking.
To master cooking and baking at altitude, the first concept you must understand is atmospheric pressure. When you're standing at any given point on the earth, you have air above you. This air has a weight, and the downward force caused by the ever-present weight of air, is known as atmospheric pressure.
It makes sense then if you're standing at sea level, which has an elevation of zero, you will have more air above you, thus more atmospheric pressure, than if you were at a higher elevation.
Now the next concept you need to understand is temperature is nothing more than a measurement of molecular movement. All molecules are in a constant state of motion, even those making up a solid block of ice. In fact, the reason why ice forms is because colder temperatures mean the water molecules are moving so slow, they adhere to one another, resulting in a solid state.
As heat is applied to that same ice cube, the water molecules start to move faster. Cooks measure this molecular movement as temperature, whether in Fahrenheit or Celsius.
When water begins to boil, it is transformed from a liquid to a gaseous state. For this phase change to happen, a lot of energy, or molecular movement, is required for the water molecules to fight back against the atmospheric pressure responsible for keeping it in its liquid state. In fact, if you were to expose a cup of room temperature water in outer space, it would boil into steam immediately since there is no atmospheric pressure for it to fight against.
This is important because at sea level, it takes 212°F/100°C of heat (molecule movement) for the water to have enough energy to change its phase from liquid to steam, at which point it escapes into the atmosphere as gas.
As you climb in elevation, you have less atmospheric pressure (again, just the weight of the air above you), so it takes less energy for water to boil.
For about every 1,000 feet (305 meters) you climb in elevation, the boiling temperature of water decreases by about 2°F/1°C.
This means if you're boiling pasta, potatoes, or blanching vegetables at a 3,000 foot (914 meter) elevation, those items will simply take longer to cook since the boiling temperature is around 206°F/97°C, as opposed to 212°F/100°C at sea level.
In our next video, we'll discuss high altitude baking, including why cakes crack, fall, and dry out (and most importantly, how to fix this).
HIGH ALTITUDE BAKING AND COOKING VIDEO LECTURE: PART TWO
Taking into consideration what we learned in our previous video, which explained the science behind atmospheric pressure and water's boiling point at various altitudes, let's take a look at how this effects baked goods, especially cakes.
First, let's stop for a second to think about what a cake is. At it's technical core, a cake is a starch gel. The flour is hydrated with liquid and fat is added to "shorten" the gluten strands, which yields a more tender product. But for the hydrated starch to actually set as a gel, it must reach a temperature ranging from 190-205°F/87-96°C.
As the cake bakes at altitude, the water contained in the batter will begin to evaporate at a lower temperature, yielding a drier product than the same recipe at sea level.
Another fact in play is cakes will also expand (rise) faster at altitude since they have less atmospheric pressure to fight against. Now consider what I just mentioned above; for a cake to fully set, the starch must gel at the same moment the cake has reached the apex of it's structural expansion. If the cake expands too much, it will collapse under it's own weight. If the cake doesn't expand enough, it will have a dense texture.
When a cake recipe gives you a time and temperature for baking, what they're really saying is "this is how long it takes for this cake to reach its maximum expansion while simultaneously hitting the temperature at which its starches will fully gel."
And even though you're using a chemical leavener in most cake formulations (baking soda and powder), as the water in the cake turns to steam, it causes upward pressure, helping the cake to rise. Again, since water will turn to steam faster at altitude, this contributes to cakes expanding more rapidly when baking at altitude.
Because the cake is reaching the apex of its expansion sooner at altitude, it has yet to achieve a temperature high enough for the starch gel to set. This causes the cake to fall under its own weight, which is why one of the most common problems in baked goods at high altitudes is a concave top.
And because the moisture in cakes will evaporate faster at altitude, it will become dry, causing the tops of baked goods to crack.
This faster expansion and evaporation of liquid is a universal issue for all baked goods at altitude, but is most noticeable in cookies, brownies, and cakes.
In our final video in this series, we'll discuss strategies for adjusting recipes for high altitude cooking and baking success.
ADJUSTING RECIPES AND INGREDIENTS FOR HIGH ALTITUDE BAKING
In our previous two videos, we talked about how atmospheric pressure effects the boiling point at altitude, and why faster evaporation causes cakes to fall, crack, and dry out.
In this video, we finish our high altitude cooking and baking series with a discussion on how to adjust recipes for high altitude baking success. To make sense of the percentages given, you should have a firm understanding of the baker's percentage.
Because liquid will evaporate faster at altitude, here's some adjustments you may need to make:
At the 3000 foot (914 meter) elevation, add 1-2 tablespoons (14-28 milliliters) of water to a single cake recipe, or about 3% based on the baker's percentage.
For every 1000 foot (305 meter) increase above 3000 feet (914 meters), add an additional tablespoon (14 milliliters) of water, or about 1%. So if you're baking at 6000Ft (1828 meters), you'll need to add a total of 4-5 tablespoons (60-73 milliliters) of water to a given cake recipe, or about 5-6% based on the baker's percentage.
Because sugar loves to bind with water, you will sometimes need to reduce the sugar content of baked goods at altitude, since less water is already available due to faster evaporation.
Decrease sugar by 1 tablespoon per cup, or 12 grams per every 64 grams of sugar, or about 6.25% based on the sugars total weight.
CHEMICAL LEAVENERS (BAKING SODA AND BAKING POWDER)
Because there is less atmospheric pressure for a rising cake to fight against at altitude, you need to decrease the amount of chemical learners you use. This will allow the cake to rise slower, giving it a chance to fully set before collapsing under its own weight.
At 3500ft (1066 meters), decrease chemical leaveners by 1/8th.
At 5,000-6000ft (1524-1828 meters), decrease chemical leaveners by 1/2.
At 6500+ft (1981+ meters), decrease chemical leaveners by as much as 3/4s.
BAKING TEMPERATURE AND TIME
Because baked goods will rise faster at altitude, it's important to raise the baking temperature so the starch gel has a chance to set by the time a cake reaches it's apex of expansion.
Raise oven temperature by 15-25°F/9-14°C (this is a universal role that should be put into play above 3,000 feet/914 haters).
Because you're raising the oven temperature, it is often helpful to decrease baking duration by 1 minute for every 6 called for. So if a cake recipe is normally baked for 30 minutes, divide 30 by 6, which equals 5, for a total bake time of 25 minutes.
If you try the first four tweaks listed above, it should solve about 95% of your high altitude baking issues. If you're still having structural issues with your baked goods (mainly not setting), try:
Starting at 3000ft/914 meters, add 1 tablespoon of flour to a single cake recipe, and an additional tablespoon for every 1000ft/305 meters above 3000ft/914 meters.
Add one egg to every cake recipe baked above 3000ft/914 meters. The extra protein in the egg will help the cake set, keeping it from collapsing.
FOR LEAN DOUGH BREADS
In my experience, bread recipes don't usually need to be adjusted for altitude. But remember, everything rises faster at altitude, so if you're having issue with your bread, here are a few things to play around with:
Because bread will rise and proof faster at altitude due to less atmospheric pressure, try slowing down the fermentation by placing it in a cooler room.
Air at altitude is much drier, so be sure to cover your bread with plastic wrap during bulk fermentation and proofing to prevent if from drying out. For more in-depth information on bread baking, listen the Stella Culinary School Podcast starting at episode 19, and then watch the videos in our Bread Baking Video Index.
If you're using commercial yeast and you find your bread is rising too quickly at altitude, try reducing the total amount of yeast by 25%.
If you're having issues with your bread drying out at altitude, raise the hydration rate by about 5% based on the baker's percentage.
If you have any questions on high altitude baking and cooking, you can post them in the comment section below.
For more resources like this, check out Stella Culinary's Food Science Video Series.
Watch Part One Of This Video
In our previous video we talked about what agar is, some of it’s properties, and why you may or may not want to use it. In this video we’re going to go over how to create an agar gel and some of it’s common pitfalls.
Agar comes in the form of a white powder, and its use percent ranges from .2% (to set a standard gel) to .5% (for a firm gel), calculated based upon the liquid’s weight.
1,000g Base Liquid
= 2g Agar to set a standard gel.
As with gelatin, agar is a hydrocolloid, meaning it can suspend or trap water, but to ensure a satisfactory outcome, it needs to be properly hydrated and dispersed.
The typical hydration procedure for agar is to first dissolve it into the liquid you want to gel by whisking, bringing the liquid to a simmer, and simmering for 4 minutes. At the end of four minutes, blend for 15-30 seconds using an immersion blender, strain, and allow to set. The added shearing power of an immersion blender will ensure even dispersion and proper hydration.
Although a standard blender can be used for dispersion (after the agar gel is simmered for 4 minutes), the rapid speed of the blender blade will incorporate extra air, which can then become suspended in the gel as it sets. These air pockets will reflect light, giving the gel an opaque appearance, instead of clear.
As we talked about in our last video, agar’s setting temperature is 95°F/33°C, and will set rapidly at this temperature. This makes agar extremely convenient to use as a gelling agent when you don’t have time to wait for gelatin to set, which takes anywhere from 12-24 at 59°F/15°C or below.
Common Agar Pitfalls
Agar is fairly easy to use, but there are some common reasons why a gel will fail or not perform as desired:
Improper Hydration: Make sure the agar is simmered in your base liquid for at least 4 minutes and then mixed with an immersion blender before straining and allowing to set.
Syneresis: Agar gels will “weep” or “leak liquid,” causing the gel to dehydrate and not perform as expected, especially when using it to set a terrine that will later be unmolded. This can be counterbalanced by the addition of .1% locust bean gum, calculated by the weight of the liquid being gelled.
Prolonged heating outside of the pH range of 5.5-8, although this is a less common problem. When we make our winter citrus terrine at Stella, with a pH of 3.2, the agar is still simmered in low pH citrus juice for 4 minutes to fully hydrate, without any adverse affect on the gel setting.
Tannic acid (commonly found in red wine and tea), in a known inhibitor of agar gels, but can counter balanced by the addition of 1% glycerol, based on the liquid’s weight.
If left uncovered, agar gels will dehydrate, causing them to loose moisture, which will adversely affect the gel’s texture. However, agar will swell in the presence of moisture, meaning gels can be rested in liquid containing a complimentary flavor, preserving its texture and enhancing it’s taste.
What Is Agar Good At?
Unlike gelatin, agar allows you to create vegetarian/vegan gels (since it’s seaweed based), will work in acidic environments, can tolerate high alcohol percentages (about 40%), and is resistant to proteolytic enzymes found in some fresh fruits including kiwi, papaya, pineapple, peach, mango, guava, and fig.
Basic Citrus Terrine Formula:
Because I used the example of the citrus terrine multiple times in our two agar videos, I’ve listed the formula and process below for reference. Please not that a working knowledge of calculating recipes based on the baker’s percentage is assumed.
100% Citrus Supremes and Juice
Add together the weight of above ingredients and then calculate the following:
.3% Agar (To set the gel)
.1% Locust Bean Gum (To keep agar gel from weeping)
Drain liquid from citrus supremes.
Combine in a pot with agar and locust bean gum.
Bring to a simmer, simmer for 4 minutes, and then blend with an immersion blender.
Heat citrus supremes in an oven or over a steamer to about 100°F/38°C. This is to keep the agar liquid from setting as soon as it hits the otherwise cold citrus segments.
Combine hot agar liquid with warm citrus supremes in a mixing bowl, gently fold together, and place in a terrine mold lined with plastic wrap.
Optional: place a flat tray on top of the terrine with weights. The pressure will cause the terrine to compact, yielding a more even texture.
Allow to set in the refrigerator overnight.
The next day, un-mold terrine, slice and serve.
Note: The terrine can be pre-sliced and allowed to set in a flavored liquid to increase water retention and enhance overall taste. A good example would be apple or orange juice flavored with fresh vanilla bean, toasted spices, etc. The terrine will then swell with this liquid, giving it extra flavor and a “juicy” mouthfeel.
Place a large, tall container of neutral flavored oil (like canola) in the freezer, until it starts to thicken, but pull before it solidifies (about 2-3 hours).
Fill a squeeze bottle with hot agar liquid, and drip into chilled oil. As the agar drops to the bottom of the oil, it will gel into the form of a sphere.
Pass oil through a strainer to remove agar spheres, rinse under cold water, and store in flavored liquid.
Agar Fluid Gel
Set liquid with .3% agar by weight.
Blend smooth in a blender, using an auger to move chunks around until it is evenly blended. Additional liquid or water can be added during the blending process to thin if necessary.
Pass through a fine mesh strainer and reserve in an airtight container.
This “fluid gel” will have the consistency of a medium body mayonnaise, but will have a pure flavor, since the added viscosity is achieved by using a small amount of agar.
As you can see, agar can be used to achieve certain things gels and textures that simply isn’t possible with gelatin. For a complete break down of the difference between agar and gelatin, please watch the final video in this series, “Agar and Gelatin Compared.”
Watch Part Two Of This Video
Although agar has only recently emerged as a common gelling agent in modern western kitchens, it has been used in asian countries for centuries as their go-to gelling agent. A polysaccharide derived from red algae, agar is a great alternative to gelatin when a vegan or vegetarian gel is needed, or when attempting to gel liquids that normally will break down gelatin because of low pH, high alcohol, or proteolytic enzymes in fresh fruits.
One of the unique qualities of an agar gel is “hysteresis,” meaning there’s a large differential between agar’s setting and melting temperature (95°F/33°C and 175°F/80°C respectively). This makes it possible to serve a warm gel using agar, something that isn’t possible with traditional gelatin based gels.
Agar also sets rapidly above room temperature (95°F/33°C), within a matter of minutes, as opposed to gelatin, which takes 12-24 hours to fully set, once it’s core reaches 59°F/15°C.
The appearance of an Agar gel can range from clear to opaque, depending on what’s being gelled and the quality of the agar, and has a texture that ranges from firm to brittle. If too much agar is used to set a gel, the texture can become “crumbly” and unpleasant, especially since the heat from our mouth is well below it’s melting point.
However, an agar gel can be made less brittle and given an elastic texture with the addition of sorbitol or glycerol, usually around 1% by the weight of the entire gel being set.
One of the big advantages to using an agar gel is its low pH tolerance, with a range of 2.5-10. This makes it possible to set acidic terrines and gels, and is what we used last winter to create a seasonal citrus terrine with a pH of 3.2. This could not be achieved by using gelatin with its pH tolerance of 4-10.
Agar can also create what’s called a “fluid gel;” in this application it’s first allowed to set, and then blended smooth in a blender. When transforming a liquid with the viscosity of water into a fluid gel, usually .3% agar is added (based on the liquids weight), hydrated, allowed to set, and then blended smooth.
For more information, please refer to our next post in our Agar series, “How to Create an Agar Gel Plus Common Pitfalls.”
Consommé...the old school Frenchy soup with crystal clarity and robust flavors that dwells in the nightmares of culinary school students around the world. While feared and loathed for it’s finicky nature by young cooks, consommé really isn’t scary once you understand the basic concepts behind making it, and how a clarification raft works.
But before we get into the consommé making process, we first need a little perspective.
Flavor, Stocks, & Broths
As I discussed extensively in the comment section of my braised beef short rib video, making stock at home is important for specific cooking applications due to the gelatin content extracted from bones; something most commercially available stocks lack. Without gelatin you’ll have a tough time making a full pan reduction sauce or glazing braised meat.
This is why traditional stocks are made with collagen rich bones like knuckles, necks and backs. When moisture and heat are applied, the collagen breaks down, yielding the gelatin needed for so many professional level applications.
However, while bones contain a lot of collagen, they’re short on flavor. This usually isn't an issue since most stocks are reduced and reinforced before final use, to add flavor and increase gelatin concentration. Yet for a truly flavorful stock, you need meat, and lots of it.
Enter our quick aside concerning stocks and broths; wars of biblical proportions have been waged on internet forums between people discussing the difference between stock and broth, with the commonly accepted dogma being stock is made from bones, and broth is made from meat.
In reality, broth is a stock that hasn’t been strained before serving, while a stock is strained broth used for a secondary purpose like reduction sauces, braising, or...to make a broth. With consommé, you start with a stock, turn it into a broth by adding a raft, which then becomes a stock again once it's strained, and will then magically turn into a broth once garnished, unless it’s left ungarnished, in which case it remains a stock.
Now say that ten times fast.
The real point is, you need to have an extremely flavorful stock when making consommé because the clarification process will extract both gelatin and flavor. This means, you need a stock made with a good amount of meat, and if it makes you feel any better, you can even call it a broth. Hell, call it a “meat nectar extraction” for all I care, as long as you promise not to make a bland consommé.
If you really want a full flavored consommé, you need to do what’s called a “double stock.” My preferred method is to cut up a whole chicken, bones and all, and make either a white or roasted chicken stock, depending on your desired outcome (this, of course, assumes we're making a chicken consommé). Strain the stock, and then make a new stock, with another whole chicken, using the first stock instead of water. This is a process I also commonly refer to as “reinforcement,” since the flavor is compounded by new meat an aromatics (vegetables, herbs, and spices).
I prefer to still use bones in this double stock, because the gelatin extracted is an important component for overall mouth feel.
Once you have a solid double stock, you can then make a good consommé.
Basic Consommé Ratio
1 qt Stock
2 Egg Whites, whisked until frothy
1/2 # Meat, Ground
5.5 ounces Mirepoix (Carrots, Celery, Onions), ground or cut into a fine julienne.
This ratio expressed in the Baker’s Percentage is:
50% Meat, Ground
5% Egg Whites
15% Mirepoix, Ground or Julienned
Herbs and Spices to Taste
The exact recipe used in this video:
4 qt. Chicken Stock
2#s Chicken Meat
1 Celery Stick, (78g)
1 Carrot (167g)
1 Onion (293g)
1 Leek, White Only (96g)
1/2 bn. Tarragon (6g)
1/2 bn. Chervil (4g)
8 Egg Whites (~200g)
2 Cloves (the spice, not garlic)
Understanding The Consommé Raft
It’s important to understand the clarification of a consommé is actually done by egg whites. As the stock is slowly heated, the egg whites start to coagulate, forming a fine mesh screen which works like a built in strainer. As long as you use 5% egg whites in ratio to your stock, and heat it properly, you’ll end up with a clear consommé.
While the large protein aggregates formed by the ground meat do aid in the clarification process, their true purpose, along with all the other ingredients besides the egg whites, is to reinforce the flavor lost during clarification. As the stock gently simmers and percolates up through the clarification raft, particulate matter which would otherwise cloud the consommé is captured, along with flavor a gelatin molecules. Since the meat and aromatic’s main purpose is to add flavor, feel free to swap any ingredients you desire to customize the taste of your finished consommé. The only caveat is, don’t use starchy vegetables like potatoes, which will yield a cloudy end product.
The meat and mirepoix are ground because more surface area equals better flavor extraction, and it makes them easier to suspended in the clarification raft.
The Consommé Process
Whisk egg whites until they begin to froth (about 30 seconds).
Mix in ground meat and mirepoix by hand, along with any other herbs & spices.
Place mixture in the bottom of a sauce pot and cover with cold stock.
Heat stock over high flame, stirring constantly until it reaches 120°F/49°, at which point the raft will begin to float.
Poke a whole in the center of the raft big enough to fit the head of a two ounce ladle.
Bring consommé to a simmer, being careful not to allow it reach to a rolling boil, which will break apart the clarification raft, ruining your consommé.
Once a simmer is achieved, turn heat down to low, and continue to simmer for 60 minutes, while pulling liquid through the center “percolation” hole with a ladle, using it to baste the raft. This will help filter the consommé while keeping the topside of the raft from drying out.
Once the consommé is clear (about 60 minutes), remove from heat.
Gently press down on raft with the bottom of a large ladle, filling it with the clarified liquid, and pass it through a chinois lined with a cheese cloth.
For added clarity, allow consommé to sit in the refrigerator overnight after it’s been strained, which will cause the fat to rise to the top and solidify. The next day, skim off all the fat.
Serve as desired, either chilled or hot, with various garnishes including brunoise and blanched vegetables, dumplings, sausage, meat balls...really anything you like. Don’t forget to season with salt.
In fine dining restaurants, it’s common to compose the garnishes in a wide bowl, and then pour the consommé table side so the guests can appreciate it’s clarity. This same serving technique is demonstrated in our “Composed Cauliflower Soup” video.
8 oz Ladle (for straining)
Chinois (fine mesh strainer)
Recommended: Warring Meat Grinder (this is what I use at the restaurant)
In our previous two posts in this gelatin series, we discussed the various types of gelatin available, and how to properly hydrate and incorporate gelatin into a base liquid we wish to set. But whether or not gelatin is the proper ingredient for the application at hand depends greatly on the recipe’s ingredients, and the overall properties of a gelatin gel.
Texture & Appearance
Gelatin based gels have a clear, transparent appearance, especially when sheets are used instead of powder. It has the best flavor retention and release of any hydrocolloid (or water trapping ingredient) available.
Because its melting point (77-104°F/22-40°C) is pretty close to body temperature, gels set with gelatin have a soft, elastic texture. Yet this can also have its own drawbacks. Although gelatin doesn’t start to truly melt until it hits about 77°F/22°, its texture starts to soften at temperatures well below this. If you’re planning on serving a gelatin based dessert or appetizer in an environment that will expose it to warm temperatures over an extended period of time, then you may have difficulties with your item maintaining its texture.
PH Tolerance (4-10)
One of the drawbacks to using gelatin is it doesn’t work well in low pH environments, with a tolerance range of 4-10 (with 7 being neutral). This becomes an issues when trying to create an acid style gel, like a citrus terrine, which can have a pH of around 3.2. If the pH in your base liquid is below 4, then a gelatin gel simply won’t set.
Gelatin gels do have some notable inhibitors you need to be aware of including salts, acids, prolonged heating, high alcohol concentration (above 40%) and protolytic enzymes found in fresh fruits such as kiwi, papaya, pineapple, peach, mango, guava and fig.
Of special note, the protolytic enzymes listed above are commonly found in meat tenderizers because of their ability to denature proteins (which also weakens a gelatin gel). However, bringing any of these fresh fruits to a simmer will deactivate these enzymes, making it possible to then gel with gelatin. However, if you’re trying to create a terrine using fresh pineapple juice and gelatin, you’re gonna have a bad time.
Gelatin does have a “setting promoter” of note, transglutaminase, which works by cross linking proteins through a very strong bond. This allows the cook to create hot gels, including rice cakes and gnocchi that are held together by their liquid, instead of the standard “binding agents” such as egg or bread crumb. Common use percent is 0.5-1% transglutaminase by weight and 1% gelatin by weight (both percentages are based on the total weight of the mixture being set).
Part One: The Basics Of
Gelatin (Sheets Vs. Powder)
Part Three: Properties Of A Gelatin
Gel Plus Some Pro Tips
In our previous video post, we discussed the difference between gelatin sheets and powder, and settled on a use percent range of 0.6% on the low side to about 1.7% on the high (firmer) side. Now that you understand the various types of gels available to you on the market, it’s time discuss how to actually use gelatin.
What Is Gelatin?
Gelatin is a hydrocolloid (meaning it can suspend or trap molecules) derived from the collagen found in animals. Collagen is a simple triple helix of gelatin, and when heat and moisture are applied, the collagen unravels into three, separate gelatin strands.
In most common large scale productions, gelatin is extracted from pig skin (which is collagen rich), and dried into either powder or sheet form (see previous post to learn the difference between the two). Since diets restricting the consumption of pork exist, it’s important to know the animal source of the gelatin you’re using, which should be labeled clearly on the package.
Although bovine gelatin is widely available as an alternative to products derived from swine, true gelatin can only be extracted from animals, meaning it’s never appropriate to use when cooking for vegans or vegetarians. However, many good substitutes for vegan gelling agents do exist, the most notable being agar, which will be the subject of an upcoming video series.
How to Properly Bloom (Hydrate) Gelatin Powders and Sheets
As mentioned above, gelatin is a hydrocolloid, and every hydrocolloid, whether pedestrian (cornstarch, flour, and gelatin) or modern (xanthan gum, alginate or kappa carrageenan) will have a specific best practice for hydration and incorporation.
When working with sheets, “bloom” (hydrate) in cold water until soft. Once pliable, squeeze any excess water from the gelatin sheet, incorporate in the liquid you wish to gel, and heat to about 122°F/50°C until completely dissolved. Gelatin can be incorporated into a hotter liquid, but prolonged heating at high temperatures, especially those approaching a boil, will result in a degradation of the gelatin’s setting strength, leading to inconsistent results. That’s why I recommend heating your liquid to no more than 140°F/60°C once the gelatin, whether powder or sheets, is incorporated.
If starting with a hot liquid, simply bloom the gelatin sheets in cold water as discussed above, while allowing the base liquid to drop below 140°F/60°C before stirring in the softened sheets.
To properly incorporate gelatin powder, the approach will be different depending on if you’re starting with a hot or cold base liquid. If starting cold, simply add the desired amount of gelatin powder to the base liquid, allow to hydrate for 5-10 minutes, and then gently heat to above 122°F/50°C, whisking occasionally, until completely dissolved.
If starting with a hot liquid, bloom powdered gelatin in a separate, complimentary cold liquid, taking into account the weight of both the hot liquid base and cold blooming liquid when calculating how much gelatin powder to use. Combine hot and cold liquid together, whisking until the gelatin powder is completely dissolved and applying additional heat if necessary. Note: even if you’re starting with a boiling hot liquid, incorporating the cold liquid plus bloomed gelatin powder shouldn’t be an issue, since once combined, the overall temperature of the liquid will drop and won’t stay hot enough to be measurably detrimental to the gelatin’s setting strength.
Because of the two step process required for incorporating gelatin powder into a hot liquid, I think this is another argument for using sheets, which have the added benefit of superior clarity and flavor.
Allowing Your Gelatin Gel to Set
Gelatin is a slow setting gel which sets at around 59°F/15°C, and needs to be kept at refrigeration temperatures for at least 6-10 hours before solidifying. Making gelatin gels at least a day before serving is extremely prudent, since gelatin can continue to set over a 24 hour period.
In our next post, we’ll discuss the specific properties of gelatin (including inhibitors and promoters) as well as best practices and common pitfalls.
Part Two: How To Use Gelatin
(Hydration + Incorporation)
Part Three: Properties Of A Gelatin
Gel Plus Some Pro Tips
In this three part video series, we discuss one of the most common gelling agents used in the western kitchen, gelatin. To lay a firm foundation, I thought it was best to start our discussion with the two major types of gelatin available to cooks, sheets and powder.
Gelatin Sheets vs. Powder
Gelatin sheets are almost exclusively used in the professional kitchen, versus powder, which is more common in supermarkets. Yet with the advent of professional level cook books, gelatin in sheet form is quickly becoming easier to find. If you’re interested in working with gelatin sheets but your local supermarket only carries powder, you can easily purchase them on Amazon.com, in their various grades. If purchasing gelatin sheets, I would recommend the silver grade, since they’re the most common in professional recipes and have an intermediate level bloom strength. This makes them easy to adapt to almost any recipe without much adjustment required.
The subject of gelatin sheets can get confusing due to their separation into grades, which are bronze, silver, gold and platinum. Each grade is associated with various “bloom strengths,” or their ability to set a gel. This means that gram for gram, platinum will set a stronger gel than gold, silver a stronger gel than bronze, etc. The bloom strength for each grade is:
Now I must admit, knowing the bloom strength of various “grades” of gelatin is pretty useless. Yes, it’s true that silver will set a more “rigid” gel than bronze, but the same results can be obtained by simply using more bronze sheets.
To compensate for the fact that one sheet has a higher bloom strength than another; each grade of gelatin is weighted differently, making their overall ability to set a gel, more or less equal. For example:
So this leads to the natural question of...if their gelling powers are pretty much the same, then why are their different grades of sheets in the first place?
And what is the answer? I have no idea. In fact, I’ve been pulling my hair out trying to figure this whole thing out, and the only thing I can think of is to make volumetric recipes easier to standardize, meaning once you get used to a particular sheet, you stick to it, and you know that x amount of sheets per cup of liquid is what your prefer for a particular result.
If it helps any, silver with a bloom strength of 160 and an average weight of 2.5g, is the most common grade of gelatin sheet found in the professional kitchen; so if you’re going to make the switch from powder, I think silver is your best option.
Professional chefs prefer sheets over powdered because the former will set a clearer, cleaner tasting gel as compared to the latter, which can sometimes have anti-caking agents and other impurities, resulting in a more opaque gel with a “dirtier” flavor.
But here’s the silver lining that you need to pull from this whole discussion: the general use percent for any given form of gelatin runs from about .6% on the low side to 1.7% on the high side. This makes it easy to find your gelatin’s sweet spot and is another great argument for why you should always be standardizing your recipes by weight (good scales are only $25, so stop procrastinating!).
As we discussed in this video, I recommend starting at 1% gelatin by your liquid’s weight (purely because it’s easy to calculate), and then scale the gelatin up or down accordingly, of course, keeping notes as you go.
In our next video post, we’ll talk about how to properly use gelatin, including hydration, melting, and how to properly incorporate both gelatin powder and sheets into your recipes.
In this video I demonstrate the simple technique of cooking pasta and then saucing it in a pan, using the fresh tomato sauce we created in our previous video.
A couple of things to keep in mind when using this technique:
Contrary to popular belief, you don't want to use a whole lot of water when boiling pasta, especially dry spaghetti. This will only dilute the starch in the water that is necessary for the sauce to properly adhere to the pasta. This starchy water can also be used to add more liquid to the sauce, which as it reduces, will be thickened by the pasta starch.
For this technique to work properly, do not strain the pasta through a colander. Simply remove it from the pot using a pasta basket or tongs as demonstrated in this video.
Feel free to add a layer of "reinforced flavors" to the simple tomato sauce used. For example, you could saute some mushrooms with shallots and garlic, deglaze with a red or white wine of choice, add a little chicken stock, and then add the fresh tomato sauce to the pan. For a richer sauce, you can even finish with a little bit of heavy cream. This video and it's accompanying sauce was purposefully left simple so you could build and customize it to your liking.
Undercook the pasta slightly and allow it to finish in the sauce pan. As the sauce reduces, it will cling to the pasta, but the additional simmering in the sauce will cause the pasta to continue to cook.
In this video, I demonstrate a super simple tomato sauce that goes great with spaghetti or pasta. Because this tomato sauce is never cooked (only quickly heated right before serving), it maintains a bright color and fresh flavor.
Simple Spaghetti - In this video, I demonstrate how to use this exact sauce for a simple spaghetti dish.
Tomato Concasse - In the above video, I make the tomato sauce using canned, whole plum tomatoes. If tomatoes are in season, you can blanch and peel as shown in the tomato concasse video, and then use them to make the sauce demonstrated in this post.