T-butyl Hydroquinone Research Articles

Retardation of rancidity in deep‐fried instant noodles (ramyon)

AbstractThe storage stability of instant fried noodles (ramyon) was determined by accelerated aging at 63 C with organoleptic evaluation of the onset of rancidity. Three methods of extending the shelf‐life of ramyon were examined: (a) addition of 200 ppm antioxidant, butylated hydroxyanisole (BHA), t‐butylhydroquinone (TBHQ), or a polymeric antioxidant (Poly‐A) to the frying (palm) oil; (b) coating the inner surface of the polyethylene package with TBHQ equivalent to 200, 500 and 1000 ppm based on the oil in the ramyon; and (c) addition of a mixture of 200 ppm TBHQ and 200 or 500 ppm disodium ethylene‐diaminetetraacetate (EDTA) to the frying oil. When the antioxidants were added to the oil, BHA and Poly‐A approximately doubled while TBHQ tripled the shelf‐life of ramyon. The mixture of TBHQ (200 ppm) and disodium EDTA (500 ppm) in the frying oil quintupled the shelf‐life. The inner surface application of TBHQ (200 ppm) extended shelf‐life twice that of an equal amount of TBHQ in the frying oil. Rancid off‐flavors developed slowest in noodles with aw 0.3. Hexanal concentration in ramyon was a good indicator of the development of oxidative rancidity. Organoleptic evaluation showed the flavor of ramyon was objectionable when hexanal concentration reached 3.5 ppm based on the weight of ramyon (as is). The relative effectiveness of antioxidants in preventing off‐flavor in ramyon could be determined from the hexanal concentration in stored ramyon.

Studies of the Improvement of Antioxidant Effect of Tocopherols. XI.

The efficiency of tocopherol (Toc) in bringing about the oxidative deterioration of emulsified fatty foods was compared with that of other antioxidants, and the synergistic effects of the antioxidants and several synergists with Toc were investigated. Margarine, as a model of an emulsified fatty food, was prepared from lard with vitamin A and β-carotene. Its stability toward oxidation was evaluated on the basis of changes in POV, and content of vitamin A and β-carotene during storage at 25°C.1) Isopropyl citrate had little effect on the oxidative deterioration of margarine. But, other antioxidants did so to a much greater degree than Toc in the order of propyl gallate (PG) _??_t-butylhydroquinone (TBHQ) >dibutyl hydroxytoluene.2) The addition of PG or TBHQ along with a mixture of d-Tocs (m-Toc) was found to provide the most protection of margarine against oxidative deterioration. However, the addition of PG or TBHQ to margarine resulted in brownish discoloration during storage.3) Citric acid and L-ascorbyl stearate (AS) enhanced synergistically the effects of m-Toc on the oxidative deterioration of margarine. The effects of AS along with m-Toc, in particular, were almost the equivalent of these of PG. However, such effects were not observed in case of L-ascorbic acid and erythorbic acid, on being added to aqueous phase of margarine.4) PG and TBHQ disappeared within a month durig storage. Thus, some of their oxidative products appear to preserve their antioxidant activity on margarine.

Studies on the Improvement of Antioxidant Effect of Tocopherols. X.

Following the same procedure described in the previous report Yukagaku, 34, 48 (1985), the fry test was conducted so as to compare the efficiency of tocopherol (Toc) with those of other several antioxidants and investigate the synergistic effects of antioxidants along with those of Toc on the oxidation of fried foods. This test was also carried out on L-ascorbyl stearate (AS), lecithin and sucrose fatty acid esters (SE).1) In the case of potato chips fried in a lard system containing only one of the antioxidants at a time, the time required to attain POV 30 of the chip lipid fraction and for odor to be perceivable during storage at 60°C was in the order of a mixture of d-Tocs (m-Toc) =t-butyl hydroquinone (TBHQ) >propyl gallate (PG) >dibutyl hydroxytoluene (BHT). This order agreed with the results from the transference ratio of each antioxidant to the potato chips (=proportion of antioxidant content in the chip lipid fraction to that added to the lard system).2) Synergistic effects on the oxidation of potato chips come about as a result of TBHQ treatment or that of PG with m-Toc. However, the effects resulting from treatment with BHT with m-Toc were the equivalent of the combined effects of all the components. However, treatment with isopropyl citrate and m-Toc together was almost the same as that resulting from m-Tocalone.3) All tested synergists were found to cause m-Toc to have greater effect on the potato chips. The time required to attain POV 30 during storage at 60°C of lecithin>AS>SE. However, addition of lecithin or SE to the fry fat resulted in browning of the potato chips and bubbling of the fat.

EFFECTS OF FOOD ANTIOXIDANTS ON PROSTAGLANDIN BIOSYNTHESIS

ABSTRACTThis study was designed to determine the influence of t‐butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and ascorbic acid on the biosynthesis of prostaglandins. Prostaglandin biosynthesis was monitored by determining the conversion of 14C‐dihomo‐gamma‐linolenic acid and 3 H‐arachidonic acid to prostaglandin E1 (PGE1), and prostaglandin E2 (PGE2), respectively, by the microsomal fraction of bovine seminal vesicles incubated under optimal conditions. The microsomal fraction converted in high yield, all‐cis 8,11,14 eicosatrienoic acid (dihomogamma linolenic acid) to PGE1 and all‐cis 5,8,11,14‐eicosatetraenoic acid (arachidonic acid) to PGE2 and in low yield, to prostaglandin F1α and F1α (PGF1α and PGF2β), respectively. Concentrations of 6.70 μM of BHA, 5.49 μM of TBHQ, and 100.6 μM of BHT resulted in a 50% inhibition of PGE1 biosynthesis, while concentrations of 3.08 μM of BHA, 6.07 μM of TBHO. and 93.0 μM of BHT resulted in a 50% inhibition of PGE2 biosynthesis in the’ systems used. 434.0 μM of ascorbic acid resulted in a 23% inhibition of PGE1 and a 43% inhibition of PGE2 biosynthesis. These results confirm that extremely low concentrations of food anti‐oxidants can interfere with prostaglandin biosynthesis.