Frozen food should it be weighed?

agahanalfred
agahanalfred Posts: 1 Member
in Food and Nutrition
Should I weigh my food if it is frozen?
Because if it is frozen does it not weigh more? If so how much more does food usually weigh if it is frozen? What is the conversion rate?

Replies

  • mtaratoot
    mtaratoot Posts: 14,815 Member
    TLDR: Yes.

    I assume you have a food scale and weigh other foods.

    If you want to be accurate, yes. Weigh what you prepare.

    I also assume you aren't eating things that are frozen except maybe ice cream. Definitely weigh that. If you take a salmon fillet out of the freezer to thaw before you cook it, you can weigh it thawed. If you are putting frozen veggies into a steamer or boiling water, weigh them.

    What would make something weigh more just because of a phase change? That frozen salmon fillet? It has water in it. When it's thawed out, it still has water in it. I actually took a Sockeye fillet out of the freezer yesterday, cut it in half, put half back in a vacuum seal bag and put the other half in the refrigerator to thaw. When it's thaw, there will be a very small amount of liquid that drains out. Maybe a milliliter or two. I will weigh the fish before I cook it. It will be an overestimate if it has bones I don't eat or if I don't eat the skin, but I'm OK with that.

  • penguinmama87
    penguinmama87 Posts: 1,155 Member
    edited January 2023
    Food CAN weigh more frozen; it depends on what it is and the method of freezing and then storage. If liquid leaves it as it thaws, it will weigh less thawed. If the seal isn't good, there may be ice crystals that form on the product that will make it seem to weigh more when frozen. The crystals will melt/evaporate when the food is thawed.

    I tend to weigh based on when I would add it to a recipe or get ready to eat it. Some things I can prep right out of the freezer so I weigh the frozen weight. These are usually fruits or vegetables so the weight difference is slight anyway and they're low calorie items. I usually thaw meat before cooking, so the thawed weight is what gets weighed. I'm usually adding to a recipe and serving, so at the end my number of servings in the recipe reflects the cooked weight. If I'm eating the meat pretty much by itself cooked, I weigh only the cooked weight to account for the loss of liquid. There is a substantial difference between raw and cooked meat, much more than frozen or thawed/raw.

    For meals I cook and then freeze for later (and I suppose this would apply to prepped freezer meals you buy at the store?), I don't adjust the weights in MFP at all. It might lose a few grams of water when I heat it back up, but not enough to make a significant difference in my calories. I assume I'm always going to have some margin of error, and that's one of the things I make allowances for.
  • AnnPT77
    AnnPT77 Posts: 36,455 Member
    Good advice above. I'd add that if it's a thing that I've purchased packaged/frozen, and it has a nutrition label, I assume the weight for the calories is a frozen weight, unless it says "as prepared". (Maybe that's optimistic, but it's worked OK for almost 8 years now . . . .).
  • kshama2001
    kshama2001 Posts: 28,055 Member
    For frozen foods like green beans and peas anyway, the USDA entry will include frozen, ex: "Beans, snap, green, frozen, all styles, unprepared" and "Peas - Green, frozen, unprepared."

    Unfortunately, the green check marks in the MFP database are used for both USER-created entries and ADMIN-created entries that MFP pulled from the USDA database. A green check mark for USER-created entries just means enough people have upvoted the entry - it is not necessarily correct.

    To find ADMIN entries for whole foods, I get the syntax from the USDA database and paste that into MFP. All ADMIN entries from the USDA will have weights as an option BUT there is a glitch whereby sometimes 1g is the option but the values are actually for 100g. This is pretty easy to spot though, as when added the calories are 100x more than is reasonable.

    https://fdc.nal.usda.gov

    Use the “SR Legacy” tab - that's what MFP used to pull in entries.

    Note: any MFP entry that includes "USDA" was USER entered.

    For packaged foods, I verify the label against what I find in MFP. (Alas, you cannot just scan with your phone and assume what you get is correct.)
  • tomcustombuilder
    tomcustombuilder Posts: 2,480 Member
    You don’t eat it frozen so weigh it after it’s thawed out.
  • paperpudding
    paperpudding Posts: 9,460 Member
    tomcustombuilder wrote: »
    You don’t eat it frozen so weigh it after it’s thawed out.


    But sometimes you put something frozen directly into your recipe.

    I often use frozen grated cheese for example without thawing it first.
  • mtaratoot
    mtaratoot Posts: 14,815 Member
    paperpudding wrote: »
    tomcustombuilder wrote: »
    You don’t eat it frozen so weigh it after it’s thawed out.


    But sometimes you put something frozen directly into your recipe.

    I often use frozen grated cheese for example without thawing it first.

    Exactly. I also weigh raw onions before I cook them. I weighed the Sockeye fillet I cooked last night before I put it in the oven. I weigh cauliflower or mushrooms before I roast them, and they do give off moisture in the cooking process. Frozen foods bought from the freezer have nutrition labels based on what's in the box usually. That said, my popcorn kernels have nutrition information for uncooked kernels (30 grams) as well as popped (three cups if I recall). I always weigh before I cook 'em because after they cook, it's too late.



  • DebbsSeattle
    DebbsSeattle Posts: 125 Member
    My frozen veg blend has the portion in frozen weight (79 grams frozen) right on the label. Frozen fish, chicken Turkey I thaw then weigh raw. When I buy meat raw in bulk, I pre-portion and vacuum seal so it is grab, thaw, log ready.
  • paints5555
    paints5555 Posts: 1,233 Member
    paperpudding wrote: »
    tomcustombuilder wrote: »
    You don’t eat it frozen so weigh it after it’s thawed out.


    But sometimes you put something frozen directly into your recipe.

    I often use frozen grated cheese for example without thawing it first.

    And I would add that unless stated otherwise, nutrition labels are as packaged. So weigh frozen.
  • paperpudding
    paperpudding Posts: 9,460 Member
    paints5555 wrote: »
    paperpudding wrote: »
    tomcustombuilder wrote: »
    You don’t eat it frozen so weigh it after it’s thawed out.


    But sometimes you put something frozen directly into your recipe.

    I often use frozen grated cheese for example without thawing it first.

    And I would add that unless stated otherwise, nutrition labels are as packaged. So weigh frozen.


    that works for things like frozen chopped onions (personally wouldn't bother logging onion weight but just using that example) that you buy frozen.

    But things like my example - I buy packets of grated cheese in fridge section and then freeze myself - so the label information is not for frozen.
  • tomcustombuilder
    tomcustombuilder Posts: 2,480 Member
    there can be a slight difference however not enough to matter given food labels can be 20% off not to mention how most people are so inaccurate with counting anyway
  • BartBVanBockstaele
    BartBVanBockstaele Posts: 623 Member
    agahanalfred wrote: »
    Should I weigh my food if it is frozen?
    Because if it is frozen does it not weigh more? If so how much more does food usually weigh if it is frozen? What is the conversion rate?
    I have no idea why food would weigh more when frozen. If you put one kg of broccoli in the freezer, it will still weigh one kg once it's frozen. At most, for some products –shrimp come to mind– there will be some water around them in order to prevent freezer burn. The difference will be minimal. Just weigh your product when it is frozen and log the calories on the package.
  • mtaratoot
    mtaratoot Posts: 14,815 Member
    BartBVanBockstaele wrote: »
    agahanalfred wrote: »
    Should I weigh my food if it is frozen?
    Because if it is frozen does it not weigh more? If so how much more does food usually weigh if it is frozen? What is the conversion rate?
    I have no idea why food would weigh more when frozen. If you put one kg of broccoli in the freezer, it will still weigh one kg once it's frozen. At most, for some products –shrimp come to mind– there will be some water around them in order to prevent freezer burn. The difference will be minimal. Just weigh your product when it is frozen and log the calories on the package.

    I think what happens physically is that the freezing process can cause ice crystals to form within the food. This can be minimized with flash-freezing and for sure is worse if you try to freeze vegetables at home. When I collect wild mushrooms, if I want to freeze them for later, I first do a dry saute' to let some of the water out and cook them fully, and THEN freeze. The quality stays good; if you freeze a raw mushroom, it won't be so good when it thaws.

    I digress.

    With a vegetable that forms ice crystals, when you thaw it and those crystals melt, the water can run off. If you lose 5% of the mass of the item (and I think it wouldn't be that much) you would end up logging fewer calories if the calorie content in the database or on the label was for before the item was frozen.

    Ice crystals forming on the outside of food products stored in a frost-free freezer may be a different story. For long term storage, use a deep freezer that doesn't have a defrost cycle.
  • BartBVanBockstaele
    BartBVanBockstaele Posts: 623 Member
    edited January 2023
    mtaratoot wrote: »
    BartBVanBockstaele wrote: »
    agahanalfred wrote: »
    Should I weigh my food if it is frozen?
    Because if it is frozen does it not weigh more? If so how much more does food usually weigh if it is frozen? What is the conversion rate?
    I have no idea why food would weigh more when frozen. If you put one kg of broccoli in the freezer, it will still weigh one kg once it's frozen. At most, for some products –shrimp come to mind– there will be some water around them in order to prevent freezer burn. The difference will be minimal. Just weigh your product when it is frozen and log the calories on the package.

    I think what happens physically is that the freezing process can cause ice crystals to form within the food. This can be minimized with flash-freezing and for sure is worse if you try to freeze vegetables at home. When I collect wild mushrooms, if I want to freeze them for later, I first do a dry saute' to let some of the water out and cook them fully, and THEN freeze. The quality stays good; if you freeze a raw mushroom, it won't be so good when it thaws.

    I digress.

    With a vegetable that forms ice crystals, when you thaw it and those crystals melt, the water can run off. If you lose 5% of the mass of the item (and I think it wouldn't be that much) you would end up logging fewer calories if the calorie content in the database or on the label was for before the item was frozen.

    Ice crystals forming on the outside of food products stored in a frost-free freezer may be a different story. For long term storage, use a deep freezer that doesn't have a defrost cycle.
    I have no argument with that. You are correct. And that is precisely why we should weigh food when it is frozen, not when it has been cooked. On average, there will be no difference. For specific portions there might be, but as you show, that difference will be minimal and well within the tolerance for foods anyway. In other words, if a bag weighs 1 kg going in the freezer, it will still weigh 1 kg when coming out. No need to worry about this. No need to complicate matters, especially not with things that cannot possibly be measured precisely.

    Changes in texture and taste, they exist. Especially as you correctly say when food has not been flash frozen.

    As for the frost-free freezer, that will only be a real problem (for weight, anyway) if the food is stored uncovered, in the open. In principle, if kept long enough, the food could be freeze-dried after some time.
  • neanderthin
    neanderthin Posts: 10,657 Member
    Calories are determined in a product like vegetables when they're fresh and unfrozen in a calorimeter and there is no difference after they're frozen and water has no calories. It's a forest and tree argument. Do food companies determine how many calories are in a frozen product after it's thawed or when it's frozen, no, doesn't happen. imo. Cheers
  • mtaratoot
    mtaratoot Posts: 14,815 Member
    paperpudding wrote: »
    But things like my example - I buy packets of grated cheese in fridge section and then freeze myself - .


    Just to clarify - I freeze the cheese,not literally freeze myself. :o:oB):D

    Self-freezing pudding.... :wink:


    neanderthin wrote: »
    Calories are determined in a product like vegetables when they're fresh and unfrozen in a calorimeter and there is no difference after they're frozen and water has no calories. It's a forest and tree argument. Do food companies determine how many calories are in a frozen product after it's thawed or when it's frozen, no, doesn't happen. imo. Cheers

    Yep. And for vegetables, the difference in weight would be de minimus. Not to even be concerned about. At an esoteric level, if X grams of fresh green peas had 100 calories, you froze them, then thawed them and they gave off some moisture, they'd still have 100 calories but weigh slightly less. De minimus. But there would be a tiny tiny difference. An entire cup of those fresh peas is hardly over that 100 calorie out-of-thin-air example. So if you lost 5% of the mass as water, you would be eating a whopping five calories more than you thought. Can it be less significant than that? Well, yes, but hardly.

    I am a recovering scientist. I can get caught up in insignificant data sometimes.

  • PAV8888
    PAV8888 Posts: 15,017 Member
    edited January 2023
    Most veggies I've checked for frozen vs raw values using USDA standard reference level data we are talking 1-2 Cal per 100g and less than 5% for the ones I've checked.

    I wouldn't be as quick to dismiss the amount of water weight added to frozen fish products based on visual comparisons across product lines and quality levels. Thankfully, other than for fattier fish such as salmon, we are not talking huge amounts of calories anyway.

    I would either go with USDA type values with weight determined once the product is thawed and dry, or with whatever the label stays if using directly from frozen.

Categories