Freezing bread affecting carbs

[beating_my_betes]

Enough to be confident in my analysis results

Well, even with exhaustive (exhausting, also) testing, it would be extremely difficult to make such claims.

Either way, I get the impression you don't want to be challenged further on this topic. So I'll leave you alone. However, if you or anyone else is interested, the various testing methodologies (both in vivo and in vitro), for the various types of resistant starch, can be found in the 'Methods of Starch Analysis' section of the link I posted earlier:

Resistant Starch: Promise for Improving Human Health - PMC

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research ...

pmc.ncbi.nlm.nih.gov

 

[Docb]

This gives a good explanation, as usual it is not as simple as it sounds.

Resistant Starch and Fiber: What's the Difference? - Nutrisense Journal

Resistant starches, insoluble fibers, and soluble fibers have a lot in common, but they’re not exactly the same. Read our article to find out more!

www.nutrisense.io

I suspected as much, which is why I asked the question.

So there are easily digested carbs, digestion resistant carbs at different levels and very difficult to digest carbs which are called fibre. The more difficult the carbs are to digest, the further through the gut they have to pass before they are digested.

Fair enough. but as far as I can see, you cannot take a food stuff, and measure these different sort of carbs in that food stuff. You cannot take a loaf of bread and measure the concentration of digestion resistant carbs, then freeze some of it and see if the digestion resistant carbs have increased. Until you can do that it is difficult to assert that freezing anything makes any difference to the levels of different sorts of carbs.

A couple of other points. Freezing things produces disruption of chemical species because of the production of ice crystals. The opposite is required to turn "ordinary" carbs into "digestion resistant" carbs. Also lowering temperature tend to slow down and stop chemical reactions, not speed them up.

Finally, if freezing bread did reduce the effect of bread on glucose production, then the T! community would know all about it. I am constantly amazed at the ability of T1's to calculate insulin needs by carb calculation and as far as I know, none of them take pre freezing into account. That tells me it is not important - the point made by @Lucyr - which I would not question.

 

[Lucyr]

Well, even with exhaustive (exhausting, also) testing, it would be extremely difficult to make such claims.

Just test your blood sugar before and after eating a sandwich, then before and after eating a frozen defrosted sandwich, take same insulin dose and compare the graphs. Do it on normal work days at lunchtime without any difference in activity levels etc. That will tell you whether it’s beneficial to freeze it or not. It isn’t rocket science.

 

[Drummer]

I took a pack of cooked meat, two slices of fresh bread, three of ham, weighed the butter and pickle, and the finished sandwich after adding lettuce. Put the loaf in the freezer meat in the fridge. Ate the sandwich, checked blood glucose levels as normal.
Next day I took the bread from the freezer, let it warm up, did the same thing checking that the parts and whole sandwich weighed the same.
Result - total sameness.
A few weeks later I did the same again, on the same day of the week, with the same results.
Having a scientific background I'm pretty sure that if there was any benefit to be gained by freezing high carb foods, I'd have seen it.

 

[beating_my_betes]

Just test your blood sugar before and after eating a sandwich, then before and after eating a frozen defrosted sandwich, take same insulin dose and compare the graphs. Do it on normal work days at lunchtime without any difference in activity levels etc. That will tell you whether it’s beneficial to freeze it or not. It isn’t rocket science.

Would be interested to continue this conversation, but only on the proviso that you're comfortable with me not having to caveat and couch my questions, walk on eggshells etc. for fear of offending you or you getting the feeling I'm calling you dishonest. This is nothing personal. I just want us all to see if we can get a better understanding of this.

No obligation, either way.

 

[Lucyr]

Would be interested to continue this conversation, but only on the proviso that you're comfortable with me not having to caveat and couch my questions, walk on eggshells etc. for fear of offending you or you getting the feeling I'm calling you dishonest. This is nothing personal. I just want us all to see if we can get a better understanding of this.

No obligation, either way.

I’m not sure what any of this post means sorry. This thread asked if freezing bread makes a difference, I gave my experience that it doesn’t, you seem to be acting like I need to write some kind of full on scientific journal article covering my methodology and controls. It’s just a sandwich.

 

[beating_my_betes]

I’m not sure what any of this post means sorry. This thread asked if freezing bread makes a difference, I gave my experience that it doesn’t, you seem to be acting like I need to write some kind of full on scientific journal article covering my methodology and controls. It’s just a sandwich.

Thanks!

 

[CliffH]

I took a pack of cooked meat, two slices of fresh bread, three of ham, weighed the butter and pickle, and the finished sandwich after adding lettuce. Put the loaf in the freezer meat in the fridge. Ate the sandwich, checked blood glucose levels as normal.
Next day I took the bread from the freezer, let it warm up, did the same thing checking that the parts and whole sandwich weighed the same.
Result - total sameness.
A few weeks later I did the same again, on the same day of the week, with the same results.
Having a scientific background I'm pretty sure that if there was any benefit to be gained by freezing high carb foods, I'd have seen it.

I too have a scientific background and I admire your rigour! Can I be a co-author on your paper? 😉.

 

[Drummer]

I too have a scientific background and I admire your rigour! Can I be a co-author on your paper? 😉.

I think that something needs to be done to break the wall of misinformation people hit straight after diagnosis - but getting people to join up here would be a good start.

 

[saz9961]

The idea is that when when frozen, or even chilled, the starch crystalises (and some papers indicate glucose can promote this), in the same way as cooked potatoes, pasta and rice are similarly affected. The process is irreversible, hance the foods can be warmed up.

Starch in bread is broken down by amylase in saliva and maltase in the small intestine to glucose.

Resistant starch though cannot be hydrolysed by these enzymes, and so is broken down in the large intestine. However, this time, its fermented by bacteria to acetyl CoA.

A bit of O-Level biology as a reminder

Some have looked at this phenomenom from the perspective of reducing colorectal cancer.

The impact of freezing and toasting on the glycaemic response of white bread - PubMed

All three procedures investigated, freezing and defrosting, toasting from fresh, and toasting following freezing and defrosting, favourably altered the glucose response of the breads. This is the first study known to the authors to show reductions in glycaemic response as a result of changes in...

pubmed.ncbi.nlm.nih.gov

Freezing bread could reduce the glycaemic response by almost 31%. All the media reports, TikToks etc are based on this 2008 paper. The paper reports an effect, in a small group. The supposition is that the change is due to the development of RS4. But likely, most of the starch just stays as starch. The study was made using homemade bread, so the effect might be different with commercial batches.

There are more studies looking at potatoes and rice. In potatoes, the RS4 content is increased by 50% when a cooked potato is chilled. What that means is a shift in resistant starch content from about 3% of the potato to 6%.

I don't think the change is all that significant for how you eat food now. Its more significant in the context of increasing the RS content in uncooked foodstuffs.

 

[CliffH]

I took a pack of cooked meat, two slices of fresh bread, three of ham, weighed the butter and pickle, and the finished sandwich after adding lettuce. Put the loaf in the freezer meat in the fridge. Ate the sandwich, checked blood glucose levels as normal.
Next day I took the bread from the freezer, let it warm up, did the same thing checking that the parts and whole sandwich weighed the same.
Result - total sameness.
A few weeks later I did the same again, on the same day of the week, with the same results.
Having a scientific background I'm pretty sure that if there was any benefit to be gained by freezing high carb foods, I'd have seen it.

I think that something needs to be done to break the wall of misinformation people hit straight after diagnosis - but getting people to join up here would be a good start.

I think that something needs to be done to break the wall of misinformation people hit straight after diagnosis - but getting people to join up here would be a good start.

If I'd been aware of this forum when I was diagnosed I'd have learnt lots of useful stuff - but how would I have sorted the wheat from the chaff? Even with my scientific background, sometimes I lose the will to live when I read long posts full of dense data and references to obscure studies.

 

[CliffH]

The idea is that when when frozen, or even chilled, the starch crystalises (and some papers indicate glucose can promote this), in the same way as cooked potatoes, pasta and rice are similarly affected. The process is irreversible, hance the foods can be warmed up.

Starch in bread is broken down by amylase in saliva and maltase in the small intestine to glucose.

Resistant starch though cannot be hydrolysed by these enzymes, and so is broken down in the large intestine. However, this time, its fermented by bacteria to acetyl CoA.

A bit of O-Level biology as a reminder

Some have looked at this phenomenom from the perspective of reducing colorectal cancer.

The impact of freezing and toasting on the glycaemic response of white bread - PubMed

All three procedures investigated, freezing and defrosting, toasting from fresh, and toasting following freezing and defrosting, favourably altered the glucose response of the breads. This is the first study known to the authors to show reductions in glycaemic response as a result of changes in...

pubmed.ncbi.nlm.nih.gov

Freezing bread could reduce the glycaemic response by almost 31%. All the media reports, TikToks etc are based on this 2008 paper. The paper reports an effect, in a small group. The supposition is that the change is due to the development of RS4. But likely, most of the starch just stays as starch. The study was made using homemade bread, so the effect might be different with commercial batches.

There are more studies looking at potatoes and rice. In potatoes, the RS4 content is increased by 50% when a cooked potato is chilled. What that means is a shift in resistant starch content from about 3% of the potato to 6%.

I don't think the change is all that significant for how you eat food now. Its more significant in the context of increasing the RS content in uncooked foodstuffs.

This explains why I only got a 'B' at Biology O-Level .

 

[Drummer]

As far as I can see - if there is no difference in my blood glucose levels, what is the point?
I don't see any difference in low and high GI and GL foods either, the only thing which causes a change is less carbohydrate in my diet.

 

[saz9961]

This explains why I only got a 'B' at Biology O-Level .

I have an unfair advantage. PhD Microbiology.

 

[CliffH]

I have an unfair advantage. PhD Microbiology.

I have an unfair advantage. PhD Microbiology.

I feel like I could probably get a PhD in bread after reading these posts

 

[Docb]

I have an unfair advantage. PhD Microbiology.

That's good, so maybe you could clear up a couple of things for me.

What is that diagram, the one you posted above, about. I also have a PhD and am quite good at diagrams but I cannot see what that one is about. Which bit is about processing carbohydrate in the gut?

Am I right in my assumption that the more complex carbohydrates are those which are more "resistant" to digestion? If so, am I being misled by my basic instincts, that freezing things will tend to break down structures rather than making them more complex? If freezing has any effect would you not expect it to reduce the amount of complex carbohydrate?

Are you suggesting that this whole thing is based on a single document without any confirmation from other work? If so, why are we discussing the topic?

 

[Martin.A]

Can I just point out that DUK has a section promoting this and if the general opinion of members is that it's spurious, as seems to be the case, then maybe DUK should consider removing it.

Mike? @everydayupsanddowns

 

[saz9961]

That's good, so maybe you could clear up a couple of things for me.

What is that diagram, the one you posted above, about. I also have a PhD and am quite good at diagrams but I cannot see what that one is about. Which bit is about processing carbohydrate in the gut?

Am I right in my assumption that the more complex carbohydrates are those which are more "resistant" to digestion? If so, am I being misled by my basic instincts, that freezing things will tend to break down structures rather than making them more complex? If freezing has any effect would you not expect it to reduce the amount of complex carbohydrate?
biota
Are you suggesting that this whole thing is based on a single document without any confirmation from other work? If so, why are we discussing the topic?

1. The diagram is for those unfamiliar with Acetyl CoA and the Krebs Cycle. Fundamentally, the starch does not end up as glucose. The excess Acetyl-CoA is used by muscle cells. Insulin has many functions, eg regulation of glucose uptake by cells, but it also modulates Acetyle CoA Carboxylase (increases activity).

2. I am only discussing starch, not carbohydrates in general. I sould correct myself; chilling and freezing of starch results in generation of RS3 (not RS4) through retrogradation. We can't really eat starch (trying eating a raw potato). Cooking breaks down the starch crystal into a viscous form (starch is of course amylose, amylopectin). That allows our amylase and maltase to start breaking it down to glucose. As the food cools, the crystalline structure tries to realign (ie. cold rice sitting out on the top is not the same as that fluffy fresh booked stuff, its changed). Chilling and freezing come into it because amylose crystallizes more quickly than amylopectin. In the cystalline form, the the bonds these enzymes hydrolyze are inaccessible, enzymology 101, lock-and-key hypothesis. You are indeed mislead. The bacterial fermentation can take a number of routes, depending on the bacterial biota. You're going to end up with Hexose, Pentose, Deoxy-hexose. Via the Pentose Phosphate pathway, these end up as Pyruvate, and thence of course Acetyle-CoA. There are a few different routes bacteria then ferment this to acetate, butyrate and propionate. Other bacteria can also take the Deoxy-hexose, to 1,2-Propanediol and then to Propionate. This is a significant process in nutritional science.

3. As I said, media reports and Tiktok highlighting this are referencing the Oxford-Brookes report. But there is other information in the literature. The 2008 paper is well cited (in 80 papers it seems). I suspect the work came out of observations that the quality of doughs changed when frozen.

4. I have no idea why this topic was started, Not a telepath.

My PhD was in marine microbial ecology, looking at particular methylotrophic enzymatic pathways, but most of my career has been in infectious diseases (everything). What area was your PhD?

 

[beating_my_betes]

I too have a scientific background and I admire your rigour! Can I be a co-author on your paper? 😉.

Could you perhaps explain to me where you see the rigour in this case?

Thanks!

 

[beating_my_betes]

We can't really eat starch (trying eating a raw potato).

Many people eat both normal and sweet potatoes raw. We are also able to consume starch in bananas and plantains.

And let us not forget NUTCRACKER MAN™

Two million years ago, human relative 'Nutcracker Man' lived on tiger nuts

A new study concludes that ancient ancestors who lived in East Africa between 2.4 million-1.4 million years ago mostly ate tiger nuts with additional nourishment from fruits and invertebrates, like worms and grasshoppers. The study examines the diet of Paranthropus boisei, nicknamed "Nutcracker...

www.sciencedaily.com