Butylated hydroquinone hydroxyanisole

Antioxidants are not important only to the health conscious food manufacturers also rely on these chemicals to maintain the shelf life of their products. Synthetic antioxidants such as butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate and tert-butyl hydroquinone were widely used in food processing to control oxidation and maintain food quality. However, as these synthetic antioxidants are suspected to be carcinogenic they now have restricted use in food (Madahavi and Salunkhe, 1995). Therefore, natural antioxidant sources, especially of plant origin, are of great interest to the food industry. 

A paired-ion, reversed-phase high-performance liquid chromatographic method was developed for the simultaneous determination of sweeteners (dulcin, saccharin-Na, and acesulfame-K), preservatives (sodium dehydroacetate, SA, salicyclic acid, BA, succinic acid, methyl-para-hydroxybenzoic acid, ethyl-para-hydroxybenzoic acid, n-propyl-para-hydroxybenzoic acid, n-butyl-para-hydroxybenzoic acid, and isobutyl-para-hydroxybenzoic acid), and antioxidants (3-tertiary-butyl-4-hydroxyanisole and tertiary-butyl-hydroquinone). A mobile phase of acetonitrile-50 ml aqueous tr-hydroxyisobutyric acid solution (pH 4.5) (2.2 3.4 or 2.4 3.6, v/v) containing 2.5 mM hexadecyltrimethylammonium bromide and a Clg column with a flow rate of 1.0 ml/min and detection at 233 nm were used. This method was found to be very reproducible detection limits ranged from 0.15 to 3.00 p,g. The retention factor (k) of each additive could be affected by the concentrations of hexadecyltrimethylammonium bromide and a-hydroxyisobu-tyric acid and the pH and ratio of mobile phase. The presence of additives in dried roast beef and sugared fruit was determined. The method is suitable for routine analysis of additives in food samples (81). 

Figure 2-18 Structure of Propyl Gallate (PG), Butylated Hydroxyanisole (BHA), Butylated Hydroxy Toluene (BHT), and Tert-Butyl Hydroquinone (TBHQ)...

Primary antioxidants terminate free radical chains and function as electron donors. They include the phenolic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxy-toluene (BHT), tertiary butyl hydroquinone (TBHQ), alkylgalates, usually propylgallate (PG), and natural and synthetic tocopherols and tocotrienols. 

Synthetic antioxidants, such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PG), ascorbyl palmitate, and tertiary-butyl-hydroquinone (TBHQ), are used in soybean cooking oils and frying fats (230). These antioxidants are typically added at 0.01% for one antioxidant and 0.02% total for two or more. Natural antioxidants, derived from sage, rosemary, and green tea, are increasingly popular because of consumer preferences for natural food ingredients (231). 

Anoxomer L-Ascorbic acid Ascorbyl palmitate Ascorbyl stearate BHA BHT t-Butyl hydroquinone 3-t-Butyl-4-hydroxyanisole Calcium citrate Calcium disodium EDTA... 

From Frankel et al. (1987). Abbreviations BHA, butylated hydroxyanisole, BHT, butylated hydroxytoluene, TBHQ, fert-butyl hydroquinone. 

Tert-butyl hydroxyanisole (BHA), tert-butyl hydroxytoluene (BHT), tert-butyl hydroquinone (TBHQ) and propyl gallate (PG) are the most common synthetic phenolic... 

Butylated Hydroxyanisole. 2- and 3-/ i -Butyl-4-methoxyphenol (butylated hydroxyanisole (BHA)) is prepared from 4-methoxyphenol and tert-huty alcohol over siUca or alumina at 150°C or from hydroquinone and tert-huty alcohol or isobutene, using an acid catalyst and then methylating. It is widely used in all types of foods such as butter, lard, and other fats, meats, cereals, baked goods, candies, and beer as an antioxidant (see Antioxidants Eood additives). Its antioxidant properties are not lost during cooking so that flour, fats, and other BHA-stabiLized ingredients may be used to produce stabilized products. 

The dihydric phenols are speciality products widely used industrially and commercially. Hydroquinone and its relative, 4-methylaminophenol (metol) are the main chemicals used for development in black and white photography. Butylated hydroxyanisole, (BHA) mainly 2,6-di-tert-butyl-4-methoxyphenol (5), an important food antioxidant is synthesised from 2,4,6-tri-t-butylphenol by reaction in methanolic solution with chlorine to give 2,4,6-tri-t-butyl-4-methoxy-... 

Vogna et al. (2004) showed that UV/H2O2 (as well as molecular ozone) was effective at oxidizing transformation products of the pharmaceutical, diclofenac. Lau et al. (2007) studied the formation of a suite of ten transformation products of butylated hydroxyanisole by including 1,4-benzoquinone, f-butyl-l,4-benzoquinone, and hydroquinone. Some of the degradates were precipitated from solutions as an orange-colored solid that could be removed by filtration. The study showed that UV/ozone and ozonation were more effective than UV alone at removal of the parent and transformation products. 

Determination of intermediates in dye synthesis (anthraquinone and derivatives), azo dyes in intermediates, products, coloring solutions and industrial effluents. Determination of aggregation number of textile dyes. Determination of food colors (e.g., of tartrazine type) in soft drinks Determination of monomers (aldehydes, acrylamide, acrylonitrile, isocyanates, methyl methacrylate, styrene, vinyl acetate) in final products and industrial effluents. Determination of initiators (azodiisobutyinitrile, benzoyt peroxide, cyclohexylperoxydicarbonate, laurylperoxide), inhibitors (hydroquinones, butylated hydroxyanisole, 4-f-butyl phenolsulphide, AAphenyt- -naphthylamine) and organo-tin stabilizers in PVC plastics... 

Figure 5.13 Separation of phenolic antioxidants by thin-layer chromatography. Solvent benzene development distance 15 cm indicators (a) borate buffer (b) 0.1% 2,6-dichloro quinonechlorimide in methanol. 1 = hydroquinone monobenzyl ether 2 = 2,6-di-rerr-butyl-phenol 3 = 2,6-di-tert-butyl-4-methyl-phenol 4 = 2,6-di-tcrt-butyl-a-methoxy-4-methyl-phenol 5 = 2-a-methyl-cyclohexyl-4, 6-dimethyl-phenol 6 = butylated hydroxyanisole 7 = butylated hydroxy toluene 8 = 4,4"-bis (2,6-di-terf-butyl-phenol) 9 = 2,2"-methylene-bis (4-methyl-6-terf-butyl-phenol) 10 = 2,2"-methylene-bis (4-ethyl-6-fert-butyl-phenol) Reproduced from Kreiner and Warner, Journal of Chromatography [119]...

Hydrotreated light straight run petroluem. See Naphtha, hydrotreated light Hydrotreated middle distillate Hydrotreated middle petroleum distillate. See Petroleum distillates, hydrotreated middle Hydrotreated (mild) heavy naphthenk distillate. See Petroleum distillates, heavy hydrotreated naphthenk Hydrotreated naphtha. See Naphtha Hydroxyacetic acid. See Glycolk acid Hydroxyaluminum distearate. See Aluminum distearate 4-Hydroxyanisole p-Hydroxyanisole. See Hydroquinone monomethyl ether Hydroxyanisole, butylated. SeeBHA Hydroxyhenzene. See Phenol... 

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