I needed to disable self sign-ups because I’ve been getting too many spam-type accounts. Thanks.
How Various cultures process foods that affects vitamin A content
Hey everyone. I was recently thinking about how traditionally prepared foods might affect the overall vitamin A content of the diet. I'll keep adding to this if I find new information.
Peeling, deseeding, and cooking vegetables. I remember how someone in the Paleo community talked about how Italians peeling fruits and vegetables was for the sake of reducing fiber content, which I found it very strange. Vegetable peels don't have that much fiber. And these Italians seem to do just fine eating cabbage, farro, and other high fiber foods. One theory is they were reducing the betacarotene, which is concentrated in the peel.
Smoking and curing meats. A few studies were posted showing how smoking meat further reduces the Vitamin A content. I do wonder if the same applies to smoked cheeses(I'm not going to experiment with this cause I'm not a fan)
Smoking and drying fish like herring and mackerel. These fish are typically much lower in Vitamin A(200 iu per 4 oz serving) than fattier fish like Salmon. Additionally, fish is high in taurine and DHA, which may be able to counteract some of the negative effects of Vitamin A.
Sun drying fruits. When fruits are left out in the sun, the beta carotene is typically destroyed. There are also some theories that fruits actually produce Vitamin D in response to the sun.(Mushrooms I know for a fact do this).
Kosher meat- I always found kosher meat to be very interesting. First only ruminants and poultry are considered fit for consumption. In order to make meat kosher, all the blood has to be removed from the meat through a salt brine. This removes the Vitamin A from the meat. With chicken, this is even more important. After brining, the meat is thoroughly rinsed to remove and last remnants of blood.
In order to eat liver, the blood has to be removed from the liver. In order to do this, the liver is thoroughly rinsed. Then, skewers are used to poke holes through various parts of the liver. The liver is taken outside and cooked over an open fire. The smoke goes through the punctured liver and theoretically should degrade the vitamin A further. After the liver is fully cooked, it is cooled again and rinsed again to further remove the blood. It is then typically chopped and fried, or mixed to create a pate.
**This is not meant as a guide on what is safe to eat. This is purely speculation.
About the smoked meats and cheeses - when they say there was less A, did they account for all the metabolites of vitamin A? I was reminded of something I think Grand wrote about that when milk is pasteurized, some of the retinol is coverted to retinoic acid but they don't look for the RA and so it doesn't count toward vA when they label it. But maybe I am not remembering that right.
No, you are right. Heating and oxidization will turn retinol into retinoic acid which is much worse.
Quote from Guest on January 9, 2019, 4:08 pmAbout the smoked meats and cheeses - when they say there was less A, did they account for all the metabolites of vitamin A? I was reminded of something I think Grand wrote about that when milk is pasteurized, some of the retinol is coverted to retinoic acid but they don't look for the RA and so it doesn't count toward vA when they label it. But maybe I am not remembering that right.
that is something I don't fully know about. I know that curing meat does get rid of a significant amount of liquid and oil from the meat.The oil could take with it some of the retinoid acid. I think smoke may have a unique reaction with retinol as well, but I have not found enough information on this.
The bigger problem with processed milk is that the retinol is unbound due to the homogenization of the milk. The fat in cow's milk(grass fed) also has beta carotene, which could also be problematic as it is freed from the fat.
That's fair though other cooking methods also can render fat alot and so should also decrease vA significantly depending on the cook. I always try to trim or skim or drain off fat from meats that I cook. Some commercial beef jerky I have has no fat in it so at least some of those methods are probably superior to mine at removing the fat but I read that other cured meats still have significant amounts of fats.
What does the retinol in cows milk get unbound to when homogenized? Is it retinol binding protein like how it is in humans? I'm kind of confused on if RBP is good or not.
This is a super interesting topic. My mind wanders... fascinated by how traditional food prep methods have come down through the centuries with people using these techniques that they know make their food "better", more digestible or able to be stored longer, etc, but they themselves really never knew WHY. They wouldn't have had a clue about vitamin A or many other "natural" toxins in foods. It's just really intriguing. On the subject of milk, I think today's milk is much more poisonous than it used to be, ever since they started doing "ultra" pasteurization, exposing the milk to much higher temperatures. Together with homogenization, it's a hot toxic mess! Have you ever noticed how milk never seems to spoil anymore? It has a much longer shelf life than it used to, and really doesn't even need to be refrigerated if unopened, although American consumers would freak out if their milk wasn't in a cooler!
Quote from Patti on January 15, 2019, 11:59 amThis is a super interesting topic. My mind wanders... fascinated by how traditional food prep methods have come down through the centuries with people using these techniques that they know make their food "better", more digestible or able to be stored longer, etc, but they themselves really never knew WHY. They wouldn't have had a clue about vitamin A or many other "natural" toxins in foods. It's just really intriguing. On the subject of milk, I think today's milk is much more poisonous than it used to be, ever since they started doing "ultra" pasteurization, exposing the milk to much higher temperatures. Together with homogenization, it's a hot toxic mess! Have you ever noticed how milk never seems to spoil anymore? It has a much longer shelf life than it used to, and really doesn't even need to be refrigerated if unopened, although American consumers would freak out if their milk wasn't in a cooler!
I agree. We have taken processing milk to a whole new level. The homogenized milk encapsulates the milk proteins into small liposomes potentially causing worse issues for people allergic to those proteins.
We also inject many cows with rBGH.
Then to top it off we add synthetic A.
No wonder people have problems with cow milk! 🙂