50-Minute Classroom: Measuring
13 February 2015Why does measuring weight, volume and temperature require training? Because each measuring instrument is only as good as the person who uses it. To that end, Chef Weiner offers a primer on measuring to share with your students.
By Adam Weiner, CFSE
I have been asked to give a presentation at the June 2015 Leadership Conference in Niagara Falls on the topic of how to teach basic culinary skills in 50 minutes. Before students can braise, sauté, simmer, bake, roast, poach, etc., however, they need to know the basics of knives and they need to know how to measure.
CAFÉ’s “Gold Medal Classroom” published my four-part series, “How to Buy Knives,” in October 2010, November 2010, December 2010and January 2011. This article on measuring is written as an instruction manual for your students. Please feel free to print it out and hand it to them directly.
New cooks need to learn how to measure. Although there will be many times when you will use technique and feel in cooking, you have to understand the basics of measuring and following recipes, as well. The three most common types are measurement of liquids, measurement of solids and measurement of temperature.
A. Measuring by Weight
The first thing you need to learn in measuring is how to use a scale. Surprisingly, measuring cups and measuring spoons are not as common as you might think in a commercial kitchen. Many commercial recipes give measurements by weight.
There are two reasons for this: 1) When you deal with large quantities, it is difficult to measure by individual cups or spoonfuls. (Imagine measuring 75 cups of flour or 12 tablespoons of yeast.) And 2) a given weight is always the same. One pound or 1 kilo is always 1 pound/kilo. If you ask someone to give you 8 ounces of flour, it will weigh 8 ounces. Ask for 2 cups of flour, and the weight will vary greatly depending upon how tightly the person packs the flour into the measuring cup.
There are three types of scales: balance scale, spring loaded and electric.
1. Spring Scale: In commercial kitchens, the most common is a spring scale. To use a spring scale, put the scale on a flat, level surface. Put an empty container on the scale, and zero it out by turning the dial. Add the product to the empty container.
Note: Never carry a spring scale by the top. The top plate is only held on with a few spot solders or welds, which give way easily. If it breaks, the scale is forever broken (and they aren’t cheap). The bigger problem when they break is they tend to land on your foot, and they hurt (a lot).
Spring scales usually come in two types: 2 pounds and 25 pounds. Although it seems obvious, don’t use the 25-pound scale if you are weighing something small.
2. Electronic Scale: These are becoming more popular in commercial kitchens and are now the most popular in home kitchens. Put the scale on a flat, level surface. Put an empty container on the scale (some already have special containers for this) and zero it out by pressing the button. Add the product to the empty container.
Follow the cleaning instructions carefully. If you wash it once the wrong way, you will probably destroy the scale. Cheaper than spring-loaded scales, electronic ones tend to be more fragile. Be careful how you handle them.
3. Balance Scale: Dating back thousands of years, these scales use weights to balance out each side. They are still quite common in bakeshops. Difficult to describe how to use in an article, the best thing to do is find an experienced person to show you in person. Because you can adjust the balance point, being flat and level isn’t required, but a flat, level surface will make the scale much easier to work with.
The biggest problem with balance scales is the counter-balance weights tend to get lost. A creative approach to this is to use something else with a known weight. For example, weight out a pound of beans in a special container. That is your new counter balance for 1 pound.
B. Measuring by Cups and Ounces
Every new culinary student must understand that there are liquid cups and ounces and there are solid cups and ounces. You have to use the right measuring device. There are measuring devices for liquids and measuring devices for solids. In other words, you measure flour differently than you measure water. Basically, measuring devices for solids can be leveled off, whereas measuring devices for liquids are designed for ease of pouring.
1. Measuring Solids: For measuring solids you need a cup or measuring spoon with which you can move the back of a knife across the cup or spoon to level it out. If a recipe calls for 1 cup/1 tablespoon, etc., it means 1 level cup/tablespoon. You cannot use a measuring cup meant for liquids because you cannot level it out.
Don’t believe me, and try measuring half of a cup of sugar in a liquid measuring cup and try to level it out. By the way, you use the back of the knife for two reasons: 1) You don’t want to damage the blade by having it dragged across the top of a measuring cup, which is particularly an issue if the cup is metal, and 2) the blade of most knives is curved, so it won’t go level across the top.
2. Measuring Liquids: The first thing to learn when using a liquid measuring device (be it for cups or gallons) is what each line represents. Look carefully at each different type of measuring cup you use and figure out what each line represents BEFORE you use the measuring cup. Make sure to put the cup down on a hard, level table and add the liquid until it is level with the mark.
Now, liquids tend to curve at the top, and the curve is called the meniscus. The bottom of the meniscus should be at the measuring line of the cup. You will either have to squat down or bend your head to see the measuring-cup markings. You can’t measure accurately looking down at the outside of the cup; you have to be looking at it straight across. Again, get down so you are looking straight at the level mark on the cup.
By the way, ladles and dishers (imagine ice-cream scoops) are good measurers—ladles for liquids and dishers for solids. They are labeled on the handle with a size marking. Metal spoons that you will find in a commercial kitchen are not generally calibrated, nor uniform.
C. Measuring Temperature
Thermometers for measuring cooked food are of four basic types: instant-read thermometers, digital thermometers, probe thermometers and infrared sensors.
1. Instant Read: Analog instant-read thermometers are still the most commonly used in a commercial kitchen. Instant-read is a bit misleading. They often take 15 to 30 seconds to get a reading. Most new cooks don’t know to wait long enough. The measuring area on an instant-read thermometer is from the tip to a little dimple usually a couple of inches from the tip. Look for it.
To give an accurate reading, the point to the dimple must be inserted in the food. If the point goes through the food and touches the pan or a bone, you won’t get an accurate reading. Instant-read thermometers need to be calibrated when they are new, when they are dropped and at least every two or three days. To calibrate one, make an ice-water bath of about 75% ice and 25% cold water. Wait a minute and stick in the thermometer to the dimple point. In about 20 seconds it should read 32 degrees Fahrenheit. If it doesn’t, then use the wrench that it came with (which is usually part of the case) to adjust the nut below the dial. Make the adjustment while the probe is in the ice bath.
2. Digital: Digital thermometers are the digital version of instant-read thermometers. They are easier to read and tend to get to temperature faster. Some don’t have dimples, so you have to read the instructions to see how much of the thermometer needs to be inserted. The biggest problem with them is that they need to be turned off. Some shut off automatically, but it seems that every time I reach for one it is in the ON position with a dead battery.
Both digital and instant-read thermometers need to be stored in their holders when not in use. One of the most common types of cross-contamination is from sticking the thermometer back into a case after use without cleaning and sanitizing it. DON’T DO THIS! If you check the temperature of a chicken, for example, and it is only 135 degrees, and then put the thermometer back into the case, you are placing raw chicken germs into the case. Of course, it is impossible to wash the case. Wash the thermometer according to instructions and sanitize it with a sanitizing wipe or placing the stem part of the thermometer into a sanitizing solution.
3. Probe: Probe thermometers are not frequently used in commercial kitchens, but are wonderful devices. You stick the probe into a product that takes a long time to cook, like a roast, connect the probe to a digital display, and place the display outside the oven. There are many models that work with Bluetooth so you can even carry the display with you. To check on the temperature, just look at the display. You don’t even need to open the oven. Remember that carry-over heat will cause the food to continue cooking even after you remove it from the oven, so pull the item out at a temperature below fully cooked.
4. Infrared: Infrared thermometers are great to have, and health departments love them. You point a laser light at something and an infrared source detects the temperature. The laser is only a pointer, the reading is infrared. This is important because the laser will point across the room, but the closer the infrared is to the surface, the more accurate the reading.
The biggest drawback is that the measurement is only the surface temperature of the food. For example, if you use an infrared thermometer on a whole turkey, it will tell you the temperature of the skin, but you won’t know whether the inside is cooked. Infrared thermometers are great for telling the temperature of ovens, heated pans, grills and other cooking equipment rather than the temperature of the food itself.
Remember, each measuring instrument is only as good as the person who uses it. When you start out, take your time and make sure your measurements are accurate.
Chef Adam Weiner, CFSE, teaches a 20-week Introduction to Cooking program for JobTrain on the San Francisco Peninsula, and is a frequent presenter at CAFÉ events throughout the nation.