# Weights and Measures

Ingredients:

Dried yeast 2 1/4 tsp. = 1/4 oz. = 7g = 1 packet 1 tea-spoon (tsp) = 5 ml; 1 dessert-spoon (dsp) = 2 tsp = 10 ml; 1 table-spoon (tbs) = 3 tsp = 15 ml; 2 tbs = 30 ml = 1 fl.oz. A "standard" French hen's egg weighs 60g, a USDA large egg weighs 2 oz.; the weight of an egg varies with species, breed, diet, season and age of the bird.

Ingredients vary in density, which means that the conversion, between weights and volumes, varies from one ingredient to another.

For water, the conversion is simple: one cup = ½ pound. We interpret this either, in English units, as one 8-oz cup = ½lb water, or, in metric units, as one 250ml cup = 250g of water—½ of a 500g metric pound.

DensityFoodsUSMetric
1.5Honey, corn syrup, maple syrup1 cup = 12 oz. 300g = 200ml
1Soft brown sugar, water, milk, eggs1 cup = 8 oz.250g = 250ml
7/8Granulated sugar1 cup = 7 oz.350g = 400ml
5/8Unsifted "all purpose" flour1 cup = 5 oz.250g = 400ml
½Cornmeal, cornstarch, confectioner's (icing) sugar1 cup = 4 oz.250g = 500ml
Conversion of Recipes from English to metric measures, and vice-versa

In France you will still hear people ask for une livre (c’est-à-dire 500 g ou la moitié d’un kilo) and une demi-livre (250 g).

Our conversions are designed to convert recipes from one system to the other, retaining convenient measures in each system. On this site, a recipe calling for 1lb of flour, and ½ lb butter, say, will also specify 500g flour and 250g butter. These are not the same quantities. However, the ratio of flour to butter remains the same. When using these recipes, don't mix weights for one ingredient in pounds with quantities for another in grams, unless you're sure the quantities aren't critical. For some recipes a 10% tolerance in quantities is fine, for many we must be more exact. Using either the metric or the English measures will give the same proportins of the various ingredients. Those using the metric system will get slightly bigger portions (by around 10%)! The smaller volume of the US version may affect baking times—but not as much as the variation between ovens. Another system, sometimes useful if you have a set of balance scales, is to call the weight of an egg , "two ounces", and to use the appropriate number of eggs as weights in one pan, while balancing the eggs with equal weights of other ingredients in the other. This gives a recipe independent of any standard system of units. See the classic Victoria Sponge, Pound Cake, or quâtre quarts , for an example.

Traditionally, measuring by volume, which needs just a graduated cup as equipment, has been easier than weighing, which required an expensive, and cumbersome, balance and weights. The American pioneers developed recipes for their New World using measures, rather than weights, as they travelled light, across the continent. The British stayed at home with their weights and balances. As a result of this history, we have two fundamentally different approaches to quantifying an ingredient—by-weight, or by-volume.

Meanwhile, the French had a revolution, and introduced a new, "rational" metric system of weights and measures. Furthermore, the standardisation of volume measures proceeded independently, and so divergently, in Britain and the United States. There are two systems of units for weights—pounds and ounces, or grams and kilograms. For culinary purposes we can also limit ourselves to two fundamental systems for volumes: one based on the fluid ounce—the volume occupied by one ounce weight of water; the other on the millilitre—which we take as the volume occupied by 1 gram of water.

One pound is about 454g, but it would be bizzarre to ask for 454g of flour in a recipe. Instead, we translate an avoirdupois pound, of 16 ounces, to a metric "pound" (500g), and let "one cup" mean 250ml when using metric weights, or eight fluid ounces when working with pounds and ounces. The obsessive measurer can also take care to use a 60g egg, (the standard used in France, which equates to UK medium, and US large), as standard when working with metric weights and measures, and 22½oz/doz, US medium, eggs when working in US weights and measures. One place where the size of your eggs certainly does matter is in quiches and custards, where the proportion of egg is critical.

Be aware that US customary units, confusingly known as "English units", have a 16-ounce pint, containing two 8-ounce cups, a 32-ounce quart, and a 128-ounce gallon; UK "Imperial units", have 20-ounce pints, 40-ounce quarts, and 160-ounce gallons. In the USA it is often said that, "A pint's a pound the world around." However in Britain the saying is different, "A pint of pure water weighs a pound and a quarter." We will give all our non-metric volume measurements in ounces or 8-ounce cups. Elsewhere, you may still find references to the British 10 oz. "breakfast cup", and 6 oz. "teacup".

The account presented here is simplified. In fact, in US customary units there are three different ounces: weight, liquid measure, and dry measure. The differences are minor (about two teaspoons per cup)—certainly not noticeable in the end-result of any recipe, and without special care, undetectable with standard domestic measuring equipment and procedures. For simplicity, we use, throughout, the Imperial fluid ounce—equivalent to the volume occupied by one ounce weight of water (the ounce weight is common to the US customary and Imperial systems).

Tare The act of removing a known weight of an object, usually the weighing container, to zero a scale. Taring allows you to display the weight of the material on the scale's LCD with the weight of the material only and not the material and container. Most electronic scales allow taring to 100% of the weighing capacity. Place your mixing bowl on the scale, press tare which sets the scale back to 0, then weigh sugar directly into your mixing bowl; press tare now you're at 0 again, then weigh out your butter directly on top of your sugar, press tare, then the next ingredient, and so on.

With the advent of accurate, electronic, tare balances, measuring by volume could become a thing of the past, but culinary traditions are deeply embedded in our cultures.

8'' is, near enough, 20cm; 9'' is even closer to 23cm.

A round, 20cm-diameter cake tin, 3.2cm deep holds 1 litre.

A square 20cm, or round 23cm cake tin, 2.5cm deep holds 1 litre.

A round 8''-diameter cake tin, 1'' deep holds 3½ cups.

A square 8'', or round 9''-diameter cake tin, 1'' deep holds 4½ cups.

A square 9'' cake tin, 1'' deep holds 5½ cups.

Temperatures have their own page.