How do you calculate macros from home-made stuff?

By calculate I don't mean that when cooking you get the macros of the ingredients you put in, but rather once you've finished cooking and take a, say, 300g portion of said cooked food?

See the trouble I had was I made some chicken-macaroni-casserole and got the ingredients' macros and I weighed it after cooking, removed the weight, and got the weight I thought was the foods weight. I then made a meal of said ingredients macros at 1915g, which was how much it weighed. Then I could use it to get different weight macroes. So I took a 350g (weighed at the same scale) plate of the casserole and let it cool down. Later on the day I took another plate, this time 300g of weight.

Then I decided to re-weigh the leftover food, which calculated almost 800g less than when I first weighed it. That means that all the calculations I made earlier are basically worthless? The numbers don't add up, and as a very data-centric (CICO is basically how I live now) guy this really demoralizes me hard. Where do you guys think I made the critical error of miscalculation? I weighed the big dish of casserole in so many different angles to get to the number I found the most representative for the true weight. Also I'm sure of the plate weights! Just so disappointed at myself right now..

Replies

  • The simplest thing to do, is to work out how many servings a recipe will make - then work to the macros based on that rather than exact individual portion weights.

    Don't get too hung up on the most minute of details - it pays to remember that nutritional values given for foods are averages not absolutes, so no matter how meticulous you are with your weighing there is always an inherent margin of error, especially for a multi ingredient dish.

    What really matters is being consistent over time.
  • gisem17
    gisem17 Posts: 50 Member
    Is it possible that 150g of water evaporated while the dish was cooling down?
  • PAV8888
    PAV8888 Posts: 13,585 Member
    edited April 2021
    You did weight after you finished cooking, right?

    But with a big enough pot, and the right types of food, 150g of additional evaporation post cooking might be possible

    Could also be a scale error (not straight, forgot to tare, near scale limits, hot food heating the scale and changing the results)

    At this stage, and personally being at maintenance, I wouldn't worry about it.

    In the past i would have just changed the numbers to make my final batch not the number I initially recorded post cooking completion, but a new total equal to the current left overs plus the amounts recorded as eaten.

    This works as long as you know that what has been eaten has always been recorded.

    Then I would go back and re log the
    marginally higherlr calories on the previous days based on this new lower total batch weight and what was eaten.

    Unless you're dealing with something of very high caloric density, you're missing 150 g which are probably in the range of 300 calories.

    So your previously eaten will go up by about 100 Cal and your remaining by about 200 Cal, in total less than a day's deficit!

    What matters is consistency over time. The occasional miscalculation will happen; but won't affect much a year down the road❣️
  • lemurcat2
    lemurcat2 Posts: 7,885 Member
    I'd estimate from your prior calculation what percentage of the food you ate initially (350/1915 or 18% or roughly 20 if you prefer). If that makes sense given your eyeball sense of how much you ate (was it about a fifth of the total, so the whole was about 5 servings?), then use that and assume the remaining is about 82% of whatever the macros and cals were in the entire dish. Using that, you can figure out what one fourth of the remaining is or a particular gram amount of the total, which you can redefine as whatever you now think it was based on current weight.

  • AnnPT77
    AnnPT77 Posts: 32,023 Member
    lemurcat2 wrote: »
    I'd estimate from your prior calculation what percentage of the food you ate initially (350/1915 or 18% or roughly 20 if you prefer). If that makes sense given your eyeball sense of how much you ate (was it about a fifth of the total, so the whole was about 5 servings?), then use that and assume the remaining is about 82% of whatever the macros and cals were in the entire dish. Using that, you can figure out what one fourth of the remaining is or a particular gram amount of the total, which you can redefine as whatever you now think it was based on current weight.

    And so many people said "why are we studying algebra: I'll never need to solve for X in real life." 😉

    OP, PAV's and Lemur's advice are good ways to achieve a good (re-)estimate.

    I'm also with PAV and Cant_think on the "one learning experience doesn't derail the whole enterprise" idea. Rough estimate is more than fine. It's a drop in the ocean of life, truly.
  • eemuman
    eemuman Posts: 2 Member
    Thanks a ton, everyone!

    So after having some time to collect myself and also read through all of your super helpful and nice comments, I came to a conclusion: Maybe everything isn't lost yet!

    I recalculated the weight with the new total (why didn't I think of this? I feel so dumb, lol), and even though some of the lost weight can be accounted for as evaporated water, I rather be more safe than sorry at this point of my journey!

    Also from now on I will be storing my cooked food in meal prep boxes, obviously with the food evenly distributed using a scale and then using the amount of boxes to calculate the macros. That way the amount of heat evaporation shouldn't change any of my calculations and cause me YET again to doubt myself.

    Thanks again everyone for your comments!
  • corinasue1143
    corinasue1143 Posts: 7,467 Member
    Hurray for lessons learned!
    Makes our journey so much easier and happier!
  • heybales
    heybales Posts: 18,842 Member
    I have several of the pots that a dish ends up in weighed already - so when I weigh the final product with dish, easy math to subtract usually.

    Tare the scale with pot and dish in it, now I know my serving size from the total as a % when I remove mine. (say 333 g / 1000g cooked)

    Apply that % (to the original list of what went into the pot that shows total calories. (say 3600 calories all items added up)
    If I'm eating 33% of the cooked dish, I'm eating 33% of what went into the dish.

    I haven't used the recipe builder in awhile, it used to make me choose a serving size near the start and I didn't like that, so now I save the ingredients into a meal, and note the cooked weight for that example in name.
    That way when I select it again, whatever % is used, and now with list of ingredients in that meal, I can adjust if I made some substitutes in ingredients.
  • lemurcat2
    lemurcat2 Posts: 7,885 Member
    eemuman wrote: »
    Also from now on I will be storing my cooked food in meal prep boxes, obviously with the food evenly distributed using a scale and then using the amount of boxes to calculate the macros. That way the amount of heat evaporation shouldn't change any of my calculations and cause me YET again to doubt myself.

    I find this approach to be convenient for myself, and I also often just eyeball it, figuring if I have four roughly equal amounts and eat all of them, then if one is a bit larger and one a bit smaller it doesn't matter.