Counting carbohydrates in home-cooked recipes

You add up the carbohydrates in all the ingredients that contain them, then divide the total by the number of servings [1]. You weigh every ingredient before cooking: the flour, the rice, the pasta, the potatoes, the sugar, the milk, the fruit and the pulses. Meat, eggs, aged cheese, oil and spices bring practically nothing, so you can leave them out without going wrong.

Use the values for the raw food and weigh everything before cooking, otherwise the calculation falls apart [2]. One hundred grams of raw rice means around 70 g of carbohydrate, no matter what it weighs after boiling. The water in the pot does not change the total, only the final weight. The most frequent mistake is confusing the carbohydrate figure for the raw weight with the values for the cooked food [3].

You have two options. The first: you cut the dish into equal servings and divide the total carbohydrate by their number, for example 12 meatballs or eight slices of pie. This method assumes the servings come out similar. The second option calls for one extra weighing, but it is more accurate [1].

First you weigh the finished dish. Then you divide the grams of carbohydrate by that weight and multiply by 100. That tells you how much carbohydrate 100 g of the final product contains [4]. You put as much as you want on your plate, weigh the portion and multiply by the carbohydrate percentage. This method suits mixed dishes and soups, where equal servings are hard to achieve. Choose the method according to how easily you manage to divide things into equal servings.

No. Cooking neither creates nor destroys carbohydrate. What changes is the weight, because food loses water when baked and fried and takes up water when boiled [4]. Rice and pasta double or even triple their weight, so the same grams of carbohydrate are now spread through a much larger amount of finished product.

The cooking method does change the speed at which food is digested. Boiling swells the starch and makes it easier to digest, so blood glucose will rise faster [5]. Cooling hardens the starch, and part of it may even end up behaving like fiber. Rice or potatoes that have been chilled and then reheated raise blood glucose somewhat more slowly [6]. In practice you count the same grams, but the ideal timing of the insulin dose may change.

If the soup is already made, you count what you can see at the bottom of the ladle. Clear stock brings very little, even if a vegetable was boiled in it. The carbohydrate comes from noodles, rice, potatoes, beans, peas, chickpeas or dumplings. Egg ribbons and meat are not counted, and sour cream adds almost nothing. Strained soup, with nothing in it, has practically no carbohydrate [7].

A broth still remains hard to estimate, because the ladle picks up something different every time. It helps to stir the pot well before serving yourself from it. The roux in some soups is added to the calculation. If you often eat the same soup, you may get the chance to work it out from the ingredients that went into it in the first place [8].

The potato and the rice in a stew are counted in full, just as they would be if they were served separately on the plate. The sauce does not make them disappear [9]. Boiled potato brings around 20 g of carbohydrate per 100 g, and boiled rice 25 g. If you weigh it raw, though, rice contains 70–75 g per 100 g. The safest option is still to weigh everything before putting it in the pot.

A sauce thickened with flour adds carbohydrate too. Two or three tablespoons of flour in a pot of four servings mean around 5 g of carbohydrate per serving, sometimes as much as 10 g [7]. Sautéed onion, tomato paste and carrot add a little, but they count in large amounts. Non-starchy vegetables remain negligible. You only reckon them in when they fill half the pot.

It depends a great deal on the sauce. Ketchup has about 25 g of carbohydrate per 100 g, which means around 4 g of carbohydrate in a tablespoon. Cooked tomato sauce has approximately 10 g of carbohydrate per 100 g. Barbecue sauce and sweet-and-sour sauce climb to 30–40 g of carbohydrate per 100 g, so they count even in small amounts [7].

Mayonnaise is practically at zero, because it is oil and egg. A plain dressing, with oil and vinegar, brings very little carbohydrate. Sweet, creamy dressings are another story, because they have added sugar. As a rule, if a sauce tastes sweet or has been thickened, you have to count it. You can only ignore the very fatty sauces and the acidic ones with no sugar [10].

Yes, because flour is almost pure starch. A level tablespoon means roughly 10 g of flour, that is around 7 g of carbohydrate. A heaped tablespoon can reach double that. Cornstarch is even more concentrated, and breadcrumbs contain around 70 g of carbohydrate per 100 g. The egg and the oil in breading bring no carbohydrate [9].

A breaded schnitzel usually adds 10–15 g of carbohydrate, but with a large piece or a thick crust it can go beyond 20 g. The most accurate approach is to weigh the flour and the breadcrumbs you used, then divide by how many pieces you made [1]. What is left on the plate or in the pan is not counted, so you subtract it from the initial amount. The same arithmetic works for meatballs made with bread or semolina.

You start from the flour in the dough, because that is where almost all the carbohydrate sits. Flour contains 70–75 g of carbohydrate per 100 g. If you used 500 g of flour, the dough brings at least 350 g of carbohydrate. You then divide that by the number of slices. If you have eight slices, that means about 45 g of carbohydrate each [1].

Then you add whatever you put on top or in the filling: the tomato sauce, the corn, the potato, the apple or the sugar. Cheese does not change the carbohydrate figure, but some cured meats have added starch and sugar. The fat in the cheese and in the dough slows down the glucose rise and spreads it over several hours [11]. The timing of the insulin dose therefore becomes just as important as its size [12].

You write them down once and reuse them. Use a notebook or a file on your phone. You need to write down the recipe, the grams of carbohydrate per serving and the weight of the serving. You also add the insulin dose that worked well, plus what your blood glucose looked like after two and after four hours. Ten recipes like that cover the most frequent home-cooked meals very well [13].

Carbohydrate counting apps save recipes and recalculate the serving on their own. You only have to enter the ingredients carefully [14]. Be careful with the changes you occasionally make while cooking. If you change the amount of flour or add an extra potato, the old figure in the app is no longer valid. A well-recorded recipe saves time. If you can, review the list from time to time together with your doctor [15].

Yes, especially with home-cooked meals that are rich in oil and meat. Fat slows down gastric emptying, so the carbohydrate reaches the blood later. On top of that, a fatty meal reduces insulin sensitivity for a few hours. A rise in blood glucose can therefore appear three to six hours after the meal [11].

The number of grams of carbohydrate does not change. What changes is only the way you deliver your insulin dose [16]. If you use an insulin pump, you can use an extended bolus or one split into two waves. With injections, the dose is sometimes split in two, given at separate times. Your doctor sets the percentages and the intervals, after seeing what your blood glucose looks like with meals of this kind [17].