Difference between revisions of "Maillard reaction"
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Styrene is a polycyclic aromatic hydrocarbon (PAH), formed during incomplete combustion of organic compounds and a Maillard reaction product (and used in dyes). Similar to toluene and ethylbenzene, syrene is also released during food decaying processes.[http://www.ncbi.nlm.nih.gov/pubmed/21541778] Environmentally, commercially manufactured polystyrene nanoparticles are taken up by algae and accumulate in fish, resulting in weight loss and altered cholesterol distribution[http://www.ncbi.nlm.nih.gov/pubmed/22384193], though may be eliminated within bile.[http://www.ncbi.nlm.nih.gov/pubmed/19799923] Chronic exposure causes remodelling of the intestinal villi[http://www.ncbi.nlm.nih.gov/pubmed/22327877] and structural changes in apolipoproteins.[http://www.ncbi.nlm.nih.gov/pubmed/21978381] Styrene oxide is neurotoxic (synergistically with acrylamide).[http://www.ncbi.nlm.nih.gov/pubmed/8442002] | Styrene is a polycyclic aromatic hydrocarbon (PAH), formed during incomplete combustion of organic compounds and a Maillard reaction product (and used in dyes). Similar to toluene and ethylbenzene, syrene is also released during food decaying processes.[http://www.ncbi.nlm.nih.gov/pubmed/21541778] Environmentally, commercially manufactured polystyrene nanoparticles are taken up by algae and accumulate in fish, resulting in weight loss and altered cholesterol distribution[http://www.ncbi.nlm.nih.gov/pubmed/22384193], though may be eliminated within bile.[http://www.ncbi.nlm.nih.gov/pubmed/19799923] Chronic exposure causes remodelling of the intestinal villi[http://www.ncbi.nlm.nih.gov/pubmed/22327877] and structural changes in apolipoproteins.[http://www.ncbi.nlm.nih.gov/pubmed/21978381] Styrene oxide is neurotoxic (synergistically with acrylamide).[http://www.ncbi.nlm.nih.gov/pubmed/8442002] | ||
− | Similar to bisphenol A and phthalates, plastic drink containers are a source of styrene exposure.[http://www.ncbi.nlm.nih.gov/pubmed/22043764] Bottled drinking water may contain styrene (up to 29.5 mcg/L; increased to 69.53 mcg/L after 1 yr storage) leached from the polystyrene (PS) bottle.[http://www.ncbi.nlm.nih.gov/pubmed/17915704] Migration of styrene from disposable cups (not paper cups) into drinks highly depends on fat content and temperature of drinks.[http://www.ncbi.nlm.nih.gov/pubmed/19750020] Olives and olive oil also contain styrene.[http://www.ncbi.nlm.nih.gov/pubmed/21111151] Blue-cheese fungi (eg Gorgonzola) also produce styrene, as well as the plastics used for packaging.[http://www.ncbi.nlm.nih.gov/pubmed/20461461] Cinnamon constituents naturally contain the styrene structure, which may get released due to the activity of fungal species present on cinnamon.[http://www.ncbi.nlm.nih.gov/pubmed/19723212] | + | Similar to bisphenol A and phthalates, plastic drink containers are a source of styrene exposure.[http://www.ncbi.nlm.nih.gov/pubmed/22043764] Bottled drinking water may contain styrene (up to 29.5 mcg/L; increased to 69.53 mcg/L after 1 yr storage) leached from the polystyrene (PS) bottle.[http://www.ncbi.nlm.nih.gov/pubmed/17915704] Migration of styrene from disposable cups (styrofoam and PS, not paper cups) into drinks highly depends on fat content and temperature of drinks.[http://www.ncbi.nlm.nih.gov/pubmed/19750020] Olives and olive oil also contain styrene.[http://www.ncbi.nlm.nih.gov/pubmed/21111151] Blue-cheese fungi (eg Gorgonzola) also produce styrene, as well as the plastics used for packaging.[http://www.ncbi.nlm.nih.gov/pubmed/20461461] Cinnamon constituents naturally contain the styrene structure, which may get released due to the activity of fungal species present on cinnamon.[http://www.ncbi.nlm.nih.gov/pubmed/19723212] |
Styrene is considered the phenylalanine-glucose counterpart of [http://www.waiwiki.org/index.php/Acrylamide acrylamide] (instead of asparagine-glucose). In the presence of sugars, phenylalanine, similarly to asparagine and lysine, can undergo carbonyl-assisted decarboxylative deamination reaction to generate styrene[http://www.ncbi.nlm.nih.gov/pubmed/15315399]. Phenylalanine heated together with 1-hydroxyacetone or methylglyoxal yielded only 0.03 mol% styrene.[http://www.ncbi.nlm.nih.gov/pubmed/19680933] | Styrene is considered the phenylalanine-glucose counterpart of [http://www.waiwiki.org/index.php/Acrylamide acrylamide] (instead of asparagine-glucose). In the presence of sugars, phenylalanine, similarly to asparagine and lysine, can undergo carbonyl-assisted decarboxylative deamination reaction to generate styrene[http://www.ncbi.nlm.nih.gov/pubmed/15315399]. Phenylalanine heated together with 1-hydroxyacetone or methylglyoxal yielded only 0.03 mol% styrene.[http://www.ncbi.nlm.nih.gov/pubmed/19680933] |
Revision as of 13:52, 18 December 2012
The Maillard reaction is responsible for many colors and flavors in foods, in combination with other processes. The heat-induced reaction of amino groups of amino acids, peptides, and proteins with carbonyl groups of reducing sugars such as glucose results in the concurrent formation of so-called Maillard browning products, such as heterocyclic amines (HCAs), acrylamides, melanoidins (food-browning), Pent-4-en-1-amine, Styrene, Acetamide, Chloropropanols and Furan, which are all present in cooked foods.
Various reducing sugars vary in reactivity. Pentoses are more reactive than hexoses, which are more reactive than disaccharides.
- Pentoses: Arabinose, xylose, lyxose, ribose, ribulose, xylulose (a pentosan is a polymere of pentoses)
- Hexoses: Glucose, fructose, mannose, galactose, allose, altrose, gulose, idose, talose, sorbose, tagatose, psicose (a hexosan is a polymere of hexoses)
- Disaccharides: Sucrose (glucose-fructose), lactose (galactose-glucose), maltose (glucose-glucose), etc.
Pent-4-en-1-amine
Is considered the lysine-glucose counterpart of acrylamide (instead of asparagine-glucose). In the presence of sugars, lysine, similarly to asparagine and phenylalanine, can undergo carbonyl-assisted decarboxylative deamination reaction to generate pent-4-en-1-amine. Alternatively, decarboxylation of lysine generates cadaverine (1,5-diaminopentane) followed by deamination to form pent-4-en-1-amine.[1]
Styrene
Styrene is a polycyclic aromatic hydrocarbon (PAH), formed during incomplete combustion of organic compounds and a Maillard reaction product (and used in dyes). Similar to toluene and ethylbenzene, syrene is also released during food decaying processes.[2] Environmentally, commercially manufactured polystyrene nanoparticles are taken up by algae and accumulate in fish, resulting in weight loss and altered cholesterol distribution[3], though may be eliminated within bile.[4] Chronic exposure causes remodelling of the intestinal villi[5] and structural changes in apolipoproteins.[6] Styrene oxide is neurotoxic (synergistically with acrylamide).[7]
Similar to bisphenol A and phthalates, plastic drink containers are a source of styrene exposure.[8] Bottled drinking water may contain styrene (up to 29.5 mcg/L; increased to 69.53 mcg/L after 1 yr storage) leached from the polystyrene (PS) bottle.[9] Migration of styrene from disposable cups (styrofoam and PS, not paper cups) into drinks highly depends on fat content and temperature of drinks.[10] Olives and olive oil also contain styrene.[11] Blue-cheese fungi (eg Gorgonzola) also produce styrene, as well as the plastics used for packaging.[12] Cinnamon constituents naturally contain the styrene structure, which may get released due to the activity of fungal species present on cinnamon.[13]
Styrene is considered the phenylalanine-glucose counterpart of acrylamide (instead of asparagine-glucose). In the presence of sugars, phenylalanine, similarly to asparagine and lysine, can undergo carbonyl-assisted decarboxylative deamination reaction to generate styrene[14]. Phenylalanine heated together with 1-hydroxyacetone or methylglyoxal yielded only 0.03 mol% styrene.[15]
Acetamide
Amides are derivates of ammonia or (carboxylated) amines. Acetamide is a carcinogenic derived from acetic acid, by dehydrating ammonium acetate[16], or by hydrolysis of acetonitrile[17]. Thermal degradation (>200°C) of chitin also yields acetamide.[18] Chitin is a good inducer for defense mechanisms in plants[19], and present in fungi, the exoskeletons of crustaceans such as crabs, lobsters and shrimps, in mollusks, and in the internal shells of squid and octopus. Acetamide is also a byproduct of thermochemical treatment of lignocellulosic biomass.[20]
Chloropropanols
3-monochloropropane-1,2-diol (3-MCPD) is a chloropropanol.
Furan
(Fur)furan (5-oxacyclopenta-1,3-diene or 1,4-epoxy-1,3-butadiene) is a toxic heterocyclic organic compound, readily converted to other compounds. Furan is present in coffee, canned and jarred food, and baby food.
- 5-hydroxymethylfurfural
- furosine