Sixty years Ago my grandmother owned a small cafe. Her "homemade" cornbread was a special favorite, and one day, one of her customers asked if she would share the recipe with him. She told him that she didn't really make it using a recipe, that she just added ingredients until it looked right, but that she would try to figure out a recipe for him. About twelve batches of somewhat questionable cornbread later, she gave up, and when he came back into the cafe, she confessed that she hadn't been able to figure it out, but that she would bake him a loaf whenever he wanted.

Back then, cooking the European way, by weight, wasn't common here in the US, and my grandmother's recipe books, when she looked at them at all, specified amounts in cups. So, when Grannie tried to recreate her cornbread recipe, she put the ingredient into a measuring cup, put some into the mixing bowl, wrote down how much that was, decided if it looked right yet, maybe added a bit more, wrote that down, and so on. It wasn't very accurate, and didn't give her a repeatable recipe. If she had been using a kitchen scale to weigh her ingredients, she wouldn't have had any problem recreating the recipe.

If my grandmother had used a kitchen scale, she would have used either a mechanical scale, or a balance. A mechanical scale is just a platform mounted on a spring that compresses proportionally to the force applied to it. The problem with mechanical scales is that if the a scale is designed to measure up to 5 lbs. then then measuring one ounce of something will be more difficult than one pound. This is because the small amount of movement in the spring caused by one ounce will be difficult to detect because the scale is designed to move evenly throughout the whole five pounds. As a kitchen scale, this leaves a lot to be desired.

The balance scale operates by performing comparisons between known masses and the object to be weighed. When using a balance to measure a cup of flour, 125 g of known mass is placed on one side of the balance while flour is placed on the other side until the mass on both sides are in balance. A beam balance has a beam with adjustable masses that move along the beam exactly like the physician's scale at your doctor's office. A good balance is extremely accurate , but as a kitchen scale, it's a bit slow.

Today, the best option for a kitchen scale is a digital scale. Digital scales work based on an electrical component called a . A simple computer in the digital scale is preloaded at the factory with a table of values that allows it to calculate the weight of a load by the change in resistance in the load cell. Better digital scales will update their readings very rapidly. This means, if you're pouring sugar into a bowl, the digital scale will provide almost instantaneous feedback so you don't pour too much.

If Grannie had owned a kitchen scale, she could easily have recreated her cornbread recipe using the Difference Method. Here's how it works.

First gather each of the ingredients you intend to use, but leave them in their storage containers. Before you do anything else, weigh each container. Don't worry about subtracting the weight of the empty container first; simply weigh the whole container and its contents and record the weights.

At this point, you could go ahead and cook your dish--it's a good way to check that you like the results!

Once you have finished cooking, go back and weigh each of the ingredient storage containers again. The weights will be less, since you used some up. Now, subtract the after-cooking weight of each container from the before-cooking weight to determine how much of the ingredient you used in your recipe. For example, suppose that before you started your flour storage container weighed 4lbs 3oz (67 oz), and afterwords it weighed 2lbs 14oz (=62oz). This means that you used 21oz, or 1lb 5oz of flour.

Using this method Grannie could have recreated her cornbread recipe with only a bit more time than it took her to create the cornbread.