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Anonymous users2024-02-15Heat treatment effects: There are both favorable and unfavorable effects, and heating can cause protein structure.
From a nutritional point of view, the changes caused by mild heat treatment are generally favorable. Such as plant protein.
Most of them have anti-nutritional factors that can be removed by heating. Heating can also eliminate some allergens. However, sometimes excessive heat treatment also causes certain adverse effects, such as causing protein amino acids.
Reactions such as desulfurization and CO2 removal occur, thereby reducing the dry weight and reducing the nutritional value of the protein.
Raise the temperature of the natural protein.
The most important effect is to cause changes in their higher order structure, and at what temperature and to what extent these changes occur and are determined by the thermal stability of the protein. The thermal stability of a particular protein is determined by many factors, including amino acid composition, protein-protein contact, binding of metal ions and other auxiliary groups, intramolecular interactions, protein concentration, water activity, pH, ionic strength, ion type, etc. Denaturation exposes hydrophobic groups and aggregates stretched protein molecules, accompanied by decreased protein solubility and increased water absorption.
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Anonymous users2024-02-14Protein denaturation.
Proteins are denatured by heat, for example, to turn egg whites into whites.
Protein denaturation (coagulation), adipogenic cyclic polymers and glyceride dipolymers (harmful substances), starch produces acrylamide (carcinogens). Hope it helps you, you can look up books like "Food Chemistry".
Attention has been sent to check only partially!
One. Select 1Food Chemistry Monographs:
justus von liebig 2.The number of chiral centers of hyamine: 2 3
The Maillard reaction is also known as the non-enzymatic browning reaction 4When the iodine value of a certain lipid is between 100 and 130, this lipid belongs to semi-dry oil 5Amino acids, one of the factors that cause proteins to produce light absorption at around 280nm are:
Tryptophan 6Vitamin A content is the most.
Simple heating can make the protein coagulated and hardened, although it can achieve the purpose of sterilization, but it is not good for human absorption. However, it can also be boiled in soup or fried and boiled with other vegetables, which can decompose the protein and facilitate the absorption of the human body.
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Anonymous users2024-02-131) Proper heat treatment is conducive to improving the nutritional value of protein.
Although thermal denaturation leads to the loss of protein biological activity, it is believed that the protein after thermal denaturation is easier to digest and absorb.
Blanching or steaming Sensan can inactivate enzymes that are not conducive to food preservation, such as lipase, lipoxidase, and polyphenol oxidase, so as to prevent food from changing color, deteriorating flavor, and losing vitamins during storage.
Thermal denaturation can inactivate some toxic proteins and anti-nutritional factors, such as botulinum toxin, protease inhibitors, lectins, etc.
2) Improper heat treatment has a lot of adverse effects on food quality.
Desulfhydryl action: the most sensitive to heat are cystine, cysteine, at H, 60% cystine is destroyed.
Deamination and neoamide bond formation: In the process of strong heat, lysine is easy to react with asparagine or glutamine to form neoamide bonds, which affects the biological valence of proteins.
Amino acid isomerization, resulting in a decrease in the nutritional value of the protein.
Chromomorphic spring bushine produces a strong mutagenic substance carboline.
When heated under alkaline conditions, the proteins are cross-linked, producing toxic dehydroalanine residues.
Carbonyl ammonia reaction.
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