When you want to know the energy content of your meals nutrition labels are a big help. It is important to compare the value given per serving with the one per 100 grams. Some serving sizes are unrealistic. No one is going to eat just 18g of Potato crisps. No one in this caravan, anyway.
When there is no nutrition label, as with fresh vegetables and meat, the Internet is a fine source of reliable information, though I usually check in a few places for an average value. Values given by weight of product are more reliable than per each. Carrots onions and potatoes are rarely small or average. Even measuring by the cup may be problematic depending on how small you chop your celery, or how tightly you pack the grated carrot. Though celery and carrot are not going to be the ingredients that cause you a problem in excess.
It is not necessary to be accurate to a decimal place, or even to a few percent. But you need to have a reasonable idea. Especially of fats, sugars and starch. And in my case, salt and protein. I don’t bother about small amounts of ingredients, like half a teaspoon of garlic or curry powder, or a spray of olive oil, I normally allow a fudge factor to cover such variations anyway. Just as I try to underestimate the amount of exercise I do. I like to feel I’m a little in energy credit.
The most helpful kitchen tool to help with kJ management is the modern digital kitchen scale. This handy little device can sit on the bench available at a moment’s notice to tell you how much your piece of chicken weighs, or if your orange, or your cup of muesli weighs about what you want.
Modern scales can be zeroed with a container on them, which means you can find out how much oatmeal your usual bowl will hold. It also means there is a handy way to find out how much butter or margarine you use, without getting butter anywhere except on your bread and the knife. Put the butter container on the scale and zero it. Then butter your bread. The negative amount now on the scale is the weight of butter used. Simple.
How much sauce do you put on your plate? Put the whole plate of food on the scales, zero and apply the sauce. Now you know. I bet it was more than a serving size as defined on the pack.
Check out my new chicken salad recipe as an example of a weighed recipe with a fudge factor that allows for a generous sprinkling of nuts to taste.