Foods discoloration

Kato, H. Chemistry of nonenzymatic browning phenomena. "Shokuhin no Henshoku to Sono Kagaku (Food Discoloration and Its Chemistry)" Nakabayashi, T., Kimura, S. and Kato, H., Eds. Korin Shoin Tokyo, 1967 pp. 223-89. 

Antioxidants play an important role in the deceleration of lipid oxidation reactions in foodstuffs. According to FDA they are defined as substances used as preservatives, with the aim to reduce spoilage, rancidity or food discoloration, which are derived from oxidations. Addition of antioxidants in foodstuffs is either intentional (direct addition into product) or symptomatic (migration of antioxidants from packaging material into product). The right and effective use of antioxidants depends on the understanding of (a) the chemistry of oils and fats, and (b) the mechanism of oxidation and their operation as substances, which result in food oxidation (Table 13.12). ... 

The calcium form of EDTA instead of free EDTA is used in many food preparations to stabilize against such deleterious effects as rancidity, loss of ascorbic acid, loss of flavor, development of cloudiness, and discoloration. The causative metal ions are sequestered by displacing calcium from the chelate, and possible problems, such as depletion of body calcium from ingestion of any excess of the free chelant, had it been used, are avoided. 

Titanium is being employed in the bleaching industry where the good corrosion resistance of the material makes it particularly suitable for equipment in both textile and paper pulp bleaching processes. In the dye-stuffs industry, the inertness of titanium eliminates any products of corrosion which might cause discoloration of the products. A similar situation can also exist in areas like the plastics, pharmaceuticals, and food-stuffs industries. 

Chloroquine Take this drug witii food or milk. Avoid foods diat acidify die urine (cranberries, plums, prunes, meats, cheeses, eggs, fish, and grains). This drug may cause diarrhea, loss of appetite, nausea, stomach pain, or vomiting. Notify die primary healtii care provider if these symptoms become pronounced. Chloroquine may cause a yellow or brownish discoloration to the urine this is normal and will go away when the drug therapy is discontinued. Notify the primary health care provider if any of the following occur ... 

Solid microcapsules using maltodextrins or starch as matrices were incorporated into cosmetic, pharmaceutical, dietetic, and food compositions using the interfacial crosslinking of flavonoids. Such microcapsules prevented discoloration while maintaining both the anti-free radical and antioxidant activities of the flavonoids." ... 

Hong, C.M., Wendorff, W.L., and Bradley, R.L., Jr., Factors affecting light-induced pink discoloration of aimatto-colored cheese, J. Food ScL, 60, 94, 1995. 

Tetracycline Tablets, capsules 250, 500 mg 500 mg twice daily before meals Maintenance dose 500 mg daily Gl upset, phototoxicity, tooth discoloration, drug and food interactions... 

Polymer-bound antioxidants must be molecularly dispersed (i.e. infinitely soluble) and cannot be physically lost from the substrate. High-MW phenolic AOs are preferred for applications requiring FDA approval, minimal discoloration, and long service life at high temperatures. Antioxidants are used for protection of polymers, plastics, elastomers, foods, fuels and lubricants. 

Carbon steel cannot be used in the production of most polymers because even trace amounts of iron discolor the product. In polymer manufacturing, usually glass-lined or stainless steel equipment must be used. Glass-lined or stainless steel equipment is required for any product that may be ingested by man. This includes all foods, pharmaceuticals, and food additives. 

Cisneros-Zevallos L, Saltveit ME and Krochta JM. 1995. Mechanism of surface white discoloration of peeled (minimally processed) carrots during storage. J Food Sci 60(2) 320-323, 333. 

The function of sodium nitrite, NaN02, as a food additive is two-fold (1) it inhibits the oxidation of blood, preventing the discoloring of red meat, and (2) it prevents the growth of botulism bacteria. There is now some controversy regarding this food additive because nitrites are suspected of combining with amines under the acidic conditions of the stomach to produce carcinogenic nitrosoamines. 

Pyrethroids are a class of synthetic chemicals that are similar in structure to natural pyrethrins. They have been used in field crops and urban pest management for nearly 30 years, and within the last 5 to 10 years new products have been registered for specific use against stored-product insects. Resmethrin is labeled for use as an aerosol in food plants, mills, and warehouse facilities, but could have potential side effects such as discoloration of surfaces and odor contamination and may be more appropriate for use in empty facilities. Labels generally state to cover any food prior to application. The pyrethroids esfenvalerate (Conquer) and prallethrin (Etoc) are also labeled for use in some situations as an aerosol space treatment in... 

Mondy NI, Munshi CB. 1988. Chemical composition of the potato as affected by the herbicide, metribuzin Enzymatic discoloration, phenols and ascorbic acid content. J Food Sci 53 475-476. 

Two different categories of pigments may be involved in lesion discoloration pigments resulting from chemical reactions of the organic contents of the lesion, and exogenous pigments from bacteria or food, which penetrate the lesion and bind to lesion constituents. 

Food pigments. Well-described are footh discolorations associated with the consumption of coffee, fea, wine, and betel nuts. This discoloration by food and beverages has been mimicked in vitro with caries lesions (Kidd et al., 1990) and sound teeth (Chan et al., 1981). 

Bromocriptine (Parl el) [Antiparkinsonian Agent/Dopamine Receptor Agonist] Uses Parkin on Dz, hyperprolactinemia, acromegaly, pituitary tumors Action Direct-acting on the striatal dopamine receptors X prolactin secretion Dose Initial, 1.25 mg PO bid titrate to effect, w/ food Caution [B, ] Contra Severe ischemic heart Dz or PVD Disp Tabs, caps SE X BP, Raynaud phenomenon (vasospastic disorder resulting in discoloration of the fmgers/toes), dizziness, N, hallucinations Interactions T Effects W/ erythromycin, fluvoxamine, nefazodone, sympathomimetics, antihypertensives X effects W/ phenothiazines, antipsychotics EMS Monitor BP may cause intolerance to EtOH OD May cause NA, severe hypotension give IV fluids symptomatic and supportive... 

One factor contributing to crop losses caused by ozone is the development of abnormal pigments which are viewed as discolored areas on foliage of ozone-sensitive cultivars. Such discoloration is esthetically unacceptable on leafy food crops and probably causes a reduction in the nutritional value of all foliar components used for food and feed. Biochemical and physiological reactions responsible for ozone-induced discolorations have not... 

Nitrous oxide can react with vitamin B12, preventing its use in red blood cell development and resulting in anemia. Use of nitrites can rapidly result in fatal methemoglobinemia, a condition that reduces the ability of the blood to transport oxygen. In 1944,11 men were admitted to a New York hospital with bluish discoloration of the skin due to methemoglobinemia. The city toxicologist and the health department eventually determined that salt shakers in a food establishment visited by all of the men contained sodium nitrite instead of table salt, sodium chloride. 

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