Nutritional loss.

[malt25]

Hi all.

I think this might be a bit of a long shot, but here goes.

I understand all vegetables, fruits, start to lose nutritional value once cut. I'm wondering at what time, rate, this process occurs. Say I cut up some fruit for a fruit salad, put it in an airtight container & place in the fridge. How long before it will have little nutritional value ? Like wise with a salad, if I prepare in the morning does it still remain reasonably nutritious that evening, or maybe next day ? I guess the process would depend on the size the piece of fruit or vegetable was cut into ?

Would appreciate any advice or sites I might visit to find out more.

Thanks in advance.

Cheers..... Mal.

[attrayant]

I understand all vegetables, fruits, start to lose nutritional value once cut.

Could you give some examples, or maybe some links with more info? As far as I'm aware, nutrients remain intact in food unless something metabolizes them (i.e., they begin spoil from bacterial activity) or affected by some other processing (e.g. structural breakdown from cooking). But for food that's just sitting there in your fridge, where would the nutrients go?

Many foods will oxidize over time, but this is not the same thing as spoilage (rot) and there's no significant nutritional impact from this. Oxidation causes noticeable changes in color and flavor, but not in nutrition or safety. Perhaps some of the fat-soluble vitamins might be affected by oxidation, but we'd probably be eating the food long before that becomes a problem.

An example: condiments like ketchup, mustard and mayo will "age" faster when left out at room temperature for extended periods of time. I have a bottle of ketchup that has become very dark red because I don't refrigerate it, but it still tastes like ketchup and hasn't technically spoiled because there's no bacterial contamination. I could delay this effect by refrigerating it and keeping the condiments in their original glass bottles instead of transferring them to plastic squeeze bottles, but... eh.

Mayo loses its tanginess over time and starts to take on an oily/greasy flavor as it oxidizes, but again this is not spoilage and as far as I'm aware there's no significant loss of nutritional value.

Perhaps a good way to tell how likely a food is to be affected by oxidation is to look at the product's "sell by" date. Contrary to popular belief, this date is not an indication of when a product will begin to spoil or become unsafe to eat. It is the manufacturer's best guess at how long their product will reatin its "freshness" before it starts to oxidize and acquire an "off" taste.

Edited February 26, 2016 by attrayant

[attrayant]

And after I wrote all of that, I see you're specifically concerned about cut up fruits and veggies. Yes of course those are more vulnerable to both oxidation and bacterial spoilage since they've been cut up and exposed to the environment. But still think (with no cite to back me up) that the short-term effect is miniscule compared to the total nutritional content of the food.

[Sheryl]

Agree, negligible effect.

[malt25]

Thanks both for your responses, much appreciated.

One of the reasons I'm confused, info from food nutritional sites as below. Would appreciate your comments.

Thanks again in advance.

"Avoid slicing vegetables too far in advance. When we slice into a vegetable or fruit, we expose the cut surfaces to heat, light, and oxygen — the nutrient destroyers. Better to wait to slice foods until we are ready to cook and eat them".

"Delay cutting.
-Buy the whole vegetable vs. pre-cut and bagged. (If you do buy bagged, use them quickly once opened.). And note, “baby” carrots are not baby carrots, but baby “shaped” adult carrots!
-Cut right before you cook. Don’t peel or pre-cut and store in fridge.
-Cut into extra large sizes to cook and cut smaller after cooking.
-Peel vegetables (beets, carrots, potatoes) after cooking, as the skin helps keep nutrients in. - See more at: http://www.thesweetbeet.com/vegetables-nutrients/#sthash.sVvPgzII.dpuf"

Thanks again..... Mal.

Delay cutting.
-Buy the whole vegetable vs. pre-cut and bagged. (If you do buy bagged, use them quickly once opened.). And note, “baby” carrots are not baby carrots, but baby “shaped” adult carrots!
-Cut right before you cook. Don’t peel or pre-cut and store in fridge.
-Cut into extra large sizes to cook and cut smaller after cooking.
-Peel vegetables (beets, carrots, potatoes) after cooking, as the skin helps keep nutrients in. - See more at: http://www.thesweetbeet.com/vegetables-nutrients/#sthash.sVvPgzII.dpuf

• Delay cutting.
  -Buy the whole vegetable vs. pre-cut and bagged. (If you do buy bagged, use them quickly once opened.). And note, “baby” carrots are not baby carrots, but baby “shaped” adult carrots!
  -Cut right before you cook. Don’t peel or pre-cut and store in fridge.
  -Cut into extra large sizes to cook and cut smaller after cooking.
  -Peel vegetables (beets, carrots, potatoes) after cooking, as the skin helps keep nutrients in.
• - See more at: http://www.thesweetbeet.com/vegetables-nutrients/#sthash.sVvPgzII.dpuf

• Delay cutting.
  -Buy the whole vegetable vs. pre-cut and bagged. (If you do buy bagged, use them quickly once opened.). And note, “baby” carrots are not baby carrots, but baby “shaped” adult carrots!
  -Cut right before you cook. Don’t peel or pre-cut and store in fridge.
  -Cut into extra large sizes to cook and cut smaller after cooking.
  -Peel vegetables (beets, carrots, potatoes) after cooking, as the skin helps keep nutrients in.
• - See more at: http://www.thesweetbeet.com/vegetables-nutrients/#sthash.sVvPgzII.dpuf

• Delay cutting.
  -Buy the whole vegetable vs. pre-cut and bagged. (If you do buy bagged, use them quickly once opened.). And note, “baby” carrots are not baby carrots, but baby “shaped” adult carrots!
  -Cut right before you cook. Don’t peel or pre-cut and store in fridge.
  -Cut into extra large sizes to cook and cut smaller after cooking.
  -Peel vegetables (beets, carrots, potatoes) after cooking, as the skin helps keep nutrients in.
• - See more at: http://www.thesweetbeet.com/vegetables-nutrients/#sthash.sVvPgzII.dpuf

[Sheryl]

Websites like this make their money stoking unnecessary fears and concerns, making it seem like getting adequate nutrition is something very difficult to achieve and requiring all manner of extensive special efforts. (After all, advising people on these efforts is what they do).

It isn't and it doesn't.

Eat a varied diet with lots of fresh fruits and veggies, whole grains rather than white bread/pasta/noodles/rice, and avoid processed foods. You'll be fine.

[Lumbini]

If man made it don't eat it [emoji87]

[malt25]

If man made it don't eat it [emoji87]

Thanks for nothing.

[attrayant]

My first reaction: What the heck is sweet beet dot com and why should I get my dietary advice from it?

Just about anyone can build a web site these days and fill it with opinions and anecdotes. What matters is whether or not those opinions are backed-up by science and/or professional recommendations. Looking at the "about" section of that web site was enough to put me off reading any more of it:

My food philosophy is this: Eat whole foods (meaning the stuff that didn’t get assembled by machines and people wearing hair-nets). Eat natural fats, meat, and all the vegetables and fruit you can find (even the non organic ones). You will feel radically better when you do.

I'm not sure why she's in favor of having people's hair fall into your food as it's being prepared. What a bizarre thing to say.

Some of the other thing she says seem to make sense, but the overall feeling of this blog is that she seems to have found something that works for her, and she wants to share it. Problem with that is there's no "one size fits all" solution to diet planning.

A bit further down, we get a list of eight things that she just "knows". She doesn't say how she knows them or whether or not she's giving professional advice:

1. The more you know about (insert any good-for-you food), the better it tastes. (This is especially true for kale.)
2. The more aware you are of how nutritious a food is, the more nutritious it will be. (Call it the food-placebo effect of food.)
3. When you eat packaged foods labeled “sugar-free” or “fat-free”, you subconsciously think they don’t count.
4. The more sugar and refined carbs you eat, the more you want to eat them.
5. Pure, unprocessed fat (which includes saturated fat) is good for you, and essential for you AND does not make YOU fat.
6. Calories lie. (A doughnut has the same as a piece of salmon.)
7. The more money you spend on quality food, the better it tastes and the less you’ll waste.
8. Confidence trumps talent in the kitchen. In life too.

A few bits of conventional wisdom with a huge helping of nonsense mixed in. Some of these are just plans silly, and much of her terminology is too imprecise to be of any real use (what is "pure" fat... as opposed to impure fat? In what way do calories lie?) Some pretty useless statements there.

Scanning through the statements you've selected from that site, I don't really see anything that alarming or interesting. Most are given as generic advice, such as you might find in any standard cook book.

What's her reason for calling out the baby carrots? That's kind of odd. Yes, they are cut from regular carrots - so what? I notice she doesn't say whether we should we eat them or not, so why the special note punctuated with an exclamation mark as though this were some sort of scandalous exposé?

The best thing I can say about that blog is that she doesn't seem to have any affiliate links back to retailers trying to sell you something, although she could still be making a small amount of money via Google's Ad Sense. But that blog seems to be getting updates only once or twice a month, so I doubt she's making much that way. To make money with Ad Sense you have to keep updating your blog quite often to show up in search results and attract traffic.

The USDA just released a new set of dietary guidelines and while it's a bit dense, in general they say to eat a wide variety of foods in moderation, and eat mostly vegetables. Eat foods that are nutrient-dense but not calorie-dense. Don't drink your calories. Don't deprive yourself of something you really like even though it might not be the best thing for you, because that'll feel like a punishment and that's a diet you won't stick to. The diet that comes closest to this is probably a Mediterranean diet.

You might be interested in following the YouTube channel "Healthcare Triage". He's a pediatrician who spends a great deal of time poring over scientific research on many topics - not just nutrition. He doesn't tell you what to think, he simply report what the research says. A few of his videos are on nutrition, but I've enjoyed almost all of them since he covers such a wide range of health-related topics.

Healthcare Triage

Edited February 26, 2016 by attrayant

[malt25]

My first reaction: What the heck is sweet beet dot com and why should I get my dietary advice from it?

Just about anyone can build a web site these days and fill it with opinions and anecdotes. What matters is whether or not those opinions are backed-up by science and/or professional recommendations. Looking at the "about" section of that web site was enough to put me off reading any more of it:

My food philosophy is this: Eat whole foods (meaning the stuff that didn’t get assembled by machines and people wearing hair-nets). Eat natural fats, meat, and all the vegetables and fruit you can find (even the non organic ones). You will feel radically better when you do.

I'm not sure why she's in favor of having people's hair fall into your food as it's being prepared. What a bizarre thing to say.

Some of the other thing she says seem to make sense, but the overall feeling of this blog is that she seems to have found something that works for her, and she wants to share it. Problem with that is there's no "one size fits all" solution to diet planning.

A bit further down, we get a list of eight things that she just "knows". She doesn't say how she knows them or whether or not she's giving professional advice:

1. The more you know about (insert any good-for-you food), the better it tastes. (This is especially true for kale.)

2. The more aware you are of how nutritious a food is, the more nutritious it will be. (Call it the food-placebo effect of food.)

3. When you eat packaged foods labeled “sugar-free” or “fat-free”, you subconsciously think they don’t count.

4. The more sugar and refined carbs you eat, the more you want to eat them.

5. Pure, unprocessed fat (which includes saturated fat) is good for you, and essential for you AND does not make YOU fat.

6. Calories lie. (A doughnut has the same as a piece of salmon.)

7. The more money you spend on quality food, the better it tastes and the less you’ll waste.

8. Confidence trumps talent in the kitchen. In life too.

A few bits of conventional wisdom with a huge helping of nonsense mixed in. Some of these are just plans silly, and much of her terminology is too imprecise to be of any real use (what is "pure" fat... as opposed to impure fat? In what way do calories lie?) Some pretty useless statements there.

Scanning through the statements you've selected from that site, I don't really see anything that alarming or interesting. Most are given as generic advice, such as you might find in any standard cook book.

What's her reason for calling out the baby carrots? That's kind of odd. Yes, they are cut from regular carrots - so what? I notice she doesn't say whether we should we eat them or not, so why the special note punctuated with an exclamation mark as though this were some sort of scandalous exposé?

The best thing I can say about that blog is that she doesn't seem to have any affiliate links back to retailers trying to sell you something, although she could still be making a small amount of money via Google's Ad Sense. But that blog seems to be getting updates only once or twice a month, so I doubt she's making much that way. To make money with Ad Sense you have to keep updating your blog quite often to show up in search results and attract traffic.

The USDA just released a new set of dietary guidelines and while it's a bit dense, in general they say to eat a wide variety of foods in moderation, and eat mostly vegetables. Eat foods that are nutrient-dense but not calorie-dense. Don't drink your calories. Don't deprive yourself of something you really like even though it might not be the best thing for you, because that'll feel like a punishment and that's a diet you won't stick to. The diet that comes closest to this is probably a Mediterranean diet.

You might be interested in following the YouTube channel "Healthcare Triage". He's a pediatrician who spends a great deal of time poring over scientific research on many topics - not just nutrition. He doesn't tell you what to think, he simply report what the research says. A few of his videos are on nutrition, but I've enjoyed almost all of them since he covers such a wide range of health-related topics.

Healthcare Triage

HCT.png

Thanks for that. looks like I've got some viewing coming up. :-)

[PocoLoco]

Some foods only release or activate certain chemical compounds AFTER / during cutting or cooking.

[attrayant]

True - an example is acrylamide, which is formed during high-temperature cooking (usually deep-frying or roasting). This is why fried food appears on the IARC class 2A schedule.

[kicking]

If man made it don't eat it [emoji87]

Thanks for nothing.

Maybe try to think a little bit here, just a little? What Lumbini is saying is avoid processed food. What's wrong with that?

[attrayant]

That's how you interpreted the post, but it's obviously not how others did. It's an overly-broad, valueless piece of "advice". I make my own meals all the time, but I don't consider them "processed".

[malt25]

If man made it don't eat it [emoji87]

Thanks for nothing.

Maybe try to think a little bit here, just a little? What Lumbini is saying is avoid processed food. What's wrong with that?

I think my thinking process is working pretty well.

If you care to READ my post, it particularly refers to fresh fruit & vegetables. Nothing to do with manufactured or processed "food"

Cheers..... Ma.

[Bantex]

Fruits that are cut and stored in the refrigerator lose from 10 to 25 percent of vitamin C in about five or six days. Cut vegetables retain their vitamin C content longer than cut fruit. According to the United States Food and Drug Administration, cut or peeled vegetables will lose about half their vitamin C content in one to two weeks.

The nutrient that suffers the most is probably vitamin C, although some vitamin A and vitamin E gets lost as well. All these nutrients serve as antioxidants. You may have noticed vitamin C (ascorbic acid), and vitamin E (tocopherol) are often used as food preservatives. But once you break through the protective coverings, the flesh inside is exposed to air. The oxygen reduces the antioxidant vitamins.

Most other nutrients, including minerals, B-complex vitamins, and fiber aren't lost after cutting or peeling the fruits and vegetables. So, even if you have to cut your fruits an veggies ahead of time, they'll still be good for you.

[malt25]

Fruits that are cut and stored in the refrigerator lose from 10 to 25 percent of vitamin C in about five or six days. Cut vegetables retain their vitamin C content longer than cut fruit. According to the United States Food and Drug Administration, cut or peeled vegetables will lose about half their vitamin C content in one to two weeks.

The nutrient that suffers the most is probably vitamin C, although some vitamin A and vitamin E gets lost as well. All these nutrients serve as antioxidants. You may have noticed vitamin C (ascorbic acid), and vitamin E (tocopherol) are often used as food preservatives. But once you break through the protective coverings, the flesh inside is exposed to air. The oxygen reduces the antioxidant vitamins.

Most other nutrients, including minerals, B-complex vitamins, and fiber aren't lost after cutting or peeling the fruits and vegetables. So, even if you have to cut your fruits an veggies ahead of time, they'll still be good for you.

Bantex, you the man... or you the woman.... whichever the case maybe.

Exactly what I was looking for. You able to let me know a site, sites, that I might be able to learn a bit more on this topic ?

Many thanks..... Mal.

NB Lumbini & kicking, not a mention of man made, processed food.

[Lumbini]

Eat nothing in a bag or box also [emoji106]

R E A L F O O D

Eat better .... Feel better [emoji263]

PS ... Also no one has brought up how cooking kills many nutrients ? When you smell that great aroma when food is cooking it's many of the nutrients going up in smoke . These posts talk about how refrigeration and other things can minimize nutrients over time but possibly nothing destroys phytochemical's and nutrients in real foods like cocking not all but reduces many .

Edited February 29, 2016 by Lumbini

[kicking]

Fruits that are cut and stored in the refrigerator lose from 10 to 25 percent of vitamin C in about five or six days. Cut vegetables retain their vitamin C content longer than cut fruit. According to the United States Food and Drug Administration, cut or peeled vegetables will lose about half their vitamin C content in one to two weeks.

The nutrient that suffers the most is probably vitamin C, although some vitamin A and vitamin E gets lost as well. All these nutrients serve as antioxidants. You may have noticed vitamin C (ascorbic acid), and vitamin E (tocopherol) are often used as food preservatives. But once you break through the protective coverings, the flesh inside is exposed to air. The oxygen reduces the antioxidant vitamins.

Most other nutrients, including minerals, B-complex vitamins, and fiber aren't lost after cutting or peeling the fruits and vegetables. So, even if you have to cut your fruits an veggies ahead of time, they'll still be good for you.

Bantex, you the man... or you the woman.... whichever the case maybe.

Exactly what I was looking for. You able to let me know a site, sites, that I might be able to learn a bit more on this topic ?

Many thanks..... Mal.

NB Lumbini & kicking, not a mention of man made, processed food.

Again I ask you to think, just a little bit. Here's the site quoted, http://nutrition.about.com/od/askyournutritionist/f/cutveg.htm

A little trick for you Mal, in the future, would be to copy and paste some of the text you are wondering about into a Google search. It's easy.

[malt25]

Eat nothing in a bag or box also [emoji106]

So far I haven't found a bag or box big enough for me to be in when I'm eating. I usually eat in my kitchen or out on the deck. I dare say you'll come up & suggest where I can get a bag or box of sufficient size, but I prefer a setting of my choosing.

If you're looking for a battle of wits or smart arse comments, be my guest. I have little doubt that if all you can offer is exhibited by your comments so far, you are completely unarmed for any battle, be it physical or mentally.

[malt25]

Fruits that are cut and stored in the refrigerator lose from 10 to 25 percent of vitamin C in about five or six days. Cut vegetables retain their vitamin C content longer than cut fruit. According to the United States Food and Drug Administration, cut or peeled vegetables will lose about half their vitamin C content in one to two weeks.

The nutrient that suffers the most is probably vitamin C, although some vitamin A and vitamin E gets lost as well. All these nutrients serve as antioxidants. You may have noticed vitamin C (ascorbic acid), and vitamin E (tocopherol) are often used as food preservatives. But once you break through the protective coverings, the flesh inside is exposed to air. The oxygen reduces the antioxidant vitamins.

Most other nutrients, including minerals, B-complex vitamins, and fiber aren't lost after cutting or peeling the fruits and vegetables. So, even if you have to cut your fruits an veggies ahead of time, they'll still be good for you.

Bantex, you the man... or you the woman.... whichever the case maybe.

Exactly what I was looking for. You able to let me know a site, sites, that I might be able to learn a bit more on this topic ?

Many thanks..... Mal.

NB Lumbini & kicking, not a mention of man made, processed food.

Again I ask you to think, just a little bit. Here's the site quoted, http://nutrition.about.com/od/askyournutritionist/f/cutveg.htm

A little trick for you Mal, in the future, would be to copy and paste some of the text you are wondering about into a Google search. It's easy.

I'll guess & say you are one of those people that reply to a question "about what motorbike should I buy" with a reply along the lines of "don't ride a bike in LOS, much too dangerous"

If you can't offer something positive or directly related to the question, why respond at all ???

I've done a fair bit of research on the topic & found some interesting albeit sometimes conflicting, information. Asking for personal advice, possibly from a member with relevant qualifications is what I was after. Read a few of the replies & you just might see some members can & do offer a logical & appropriate response.

Maybe you & your mate should get out more & away from the bar stool & laptop.

Mods, me thinks this topic is degenerating . I'm happy if you close.

Thanks..... Mal.

[kicking]

...

If you're looking for a battle of wits or smart arse comments, be my guest. I have little doubt that if all you can offer is exhibited by your comments so far, you are completely unarmed for any battle, be it physical or mentally.

It seems you are the one unarmed. Proper grammar is "be it physical or mental", not "mentally".

As for my other comment, it most certainly was helpful. Had you known how to conduct a Google search, you wouldn't have asked the question. I'm happy to have helped you.

[attrayant]

Doing a google search is like going to the library and pulling books off the shelves at random. Potentially fruitful if you know which books to look for (who in this thread knows about Google Scholar?), but next to worthless if you don't or if you lack the capacity to critically evaluate the veracity of the information you find.

You might get some valid, relevant information, but you'll most likely get 99% crap and a lot of random strangers with worthless advice like "If man made it don't eat it". Then there are sites like Mercola and Natural "news", which are the intellectual equivalent of stepping on a land mine. Not only will you get bad advice, but you might even lose a leg in the process.

And what if the OP wanted to have an actual discussion about the subject at hand? Seems to me the ideal place would be a discussion forum.

[kicking]

Doing a google search is like going to the library and pulling books off the shelves at random. Potentially fruitful if you know which books to look for (who in this thread knows about Google Scholar?), but next to worthless if you don't or if you lack the capacity to critically evaluate the veracity of the information you find.

You might get some valid, relevant information, but you'll most likely get 99% crap and a lot of random strangers with worthless advice like "If man made it don't eat it". Then there are sites like Mercola and Natural "news", which are the intellectual equivalent of stepping on a land mine. Not only will you get bad advice, but you might even lose a leg in the process.

And what if the OP wanted to have an actual discussion about the subject at hand? Seems to me the ideal place would be a discussion forum.

Agreed, however my comment was directed at a particular passage that was in question, not a general search.

[Sheryl]

Fruits that are cut and stored in the refrigerator lose from 10 to 25 percent of vitamin C in about five or six days. Cut vegetables retain their vitamin C content longer than cut fruit. According to the United States Food and Drug Administration, cut or peeled vegetables will lose about half their vitamin C content in one to two weeks.

The nutrient that suffers the most is probably vitamin C, although some vitamin A and vitamin E gets lost as well. All these nutrients serve as antioxidants. You may have noticed vitamin C (ascorbic acid), and vitamin E (tocopherol) are often used as food preservatives. But once you break through the protective coverings, the flesh inside is exposed to air. The oxygen reduces the antioxidant vitamins.

Most other nutrients, including minerals, B-complex vitamins, and fiber aren't lost after cutting or peeling the fruits and vegetables. So, even if you have to cut your fruits an veggies ahead of time, they'll still be good for you.

Bantex, you the man... or you the woman.... whichever the case maybe.

Exactly what I was looking for. You able to let me know a site, sites, that I might be able to learn a bit more on this topic ?

Many thanks..... Mal.

NB Lumbini & kicking, not a mention of man made, processed food.

Again I ask you to think, just a little bit. Here's the site quoted, http://nutrition.about.com/od/askyournutritionist/f/cutveg.htm

A little trick for you Mal, in the future, would be to copy and paste some of the text you are wondering about into a Google search. It's easy.

....Mods, me thinks this topic is degenerating . I'm happy if you close.

Thanks..... Mal.

agree.

Closed.