Because fresh blood contains albumin, it will coagulate under cooking conditions above 75 degrees Celsius, thus forming blood clots or tofu-like texture.
An article in 17 years (1) compared the differences of nutritional components among pig blood, duck blood and chicken blood (see the table below).
From the table, we can find that pig blood has the highest protein and fat content, while duck blood has the highest carbohydrate content.
The trace elements listed in the table are necessary for normal physiological functions of human body, and insufficient intake will lead to corresponding health problems. For example, insufficient iron intake can easily lead to iron deficiency anemia, which is especially important for teenagers, women in physiological period and the elderly.
Compared with the blood of these animals, pig blood has the least iron content, but the percentage of heme iron which is more easily absorbed by human body is the highest among the three animal blood, and the content in dry weight is equivalent to that of duck blood. In addition, the contents of copper and chromium in pig blood are also the highest. The highest content of zinc is chicken blood, while the highest content of magnesium and manganese is duck blood. Therefore, we can selectively eat different kinds of animal blood according to the lack of trace elements in the body.
Because of the high protein content in blood, the researchers also compared the contents of various essential amino acids (as shown in the following table).
Comparing the amino acid content in these samples with the amino acid requirements of adults recommended by WHO/FAO/UNU in 2007, we can find that animal blood is an excellent source of essential amino acids (except isoleucine).
For the content of isoleucine, the results of different studies are quite different, which may be due to the deviation caused by detection methods, so it is only for reference here. In addition, the content of essential amino acids, such as tryptophan, which was not detected in the article, was found to be less than the recommended value in other reports (2). In a word, chicken blood seems to be a better food for balancing essential amino acids because of its highest isoleucine content.
The materials used in the study are 6-month-old hybrid pigs, 42-day-old chickens (variety: Arber Acer) and 47-day-old hybrid ducks. The contents of various nutrients in the blood may vary with animal species, feed, season and age.
First of all, the fresh blood of healthy animals is sterile, but it can't avoid all kinds of pollution in the process of collection and storage. Many similar products on the market do not indicate the source and quality inspection results, so it is recommended to buy them from reliable supply channels.
Secondly, it is generally believed that there may be toxins or toxic metabolites in blood, which is actually unfounded. Any threat brought by blood products is no different from their protozoan products (meat or viscera) (3). The concern that blood may be the source of dioxins (a kind of highly toxic substances, which can cause reproductive and developmental problems, damage the immune system, interfere with hormones and even cause cancer) was also ruled out in a report in 200 1 year, which is not surprising, because dioxins will accumulate in fat, and from the above, we know that the fat content of blood is very low. However, it should be noted that eating too much food with high iron content may lead to hemochromatosis, which may cause a variety of diseases and problems, including liver damage, pulmonary effusion, dehydration, low blood pressure and neurological diseases, so don't eat too much. Normal people suggest not to eat more than two meals a week.
Happy Halloween to everyone!
(Blood is life! )
Writer: Xiyuan Lu-Ph.D. in American Nutrition Science; Moderator of "Food and Nutrition" Edition of Puke Studio; Invited columnist of "the marrow of food"
Reviewer: Chuofang–Ph.D. in Nutrition Science, USA; Invited Contributor of Puke's "Food and Nutrition" Edition
References:
1./doi/abs/ 10. 1080/ 10408398.20 1 1.605229
4.https://agris.fao.org/agris-search/search.do? recordID=QC200 160002 1