Trace Metals, Potassium Bromate and Nutritional Potentials in Bread from Bakeries in Uyo, Akwa Ibom State, Nigeria

摘要

This research assessed bread from bakeries in Uyo, Akwa Ibom State, Nigeria, for trace metals, nutritive value and potassium bromate using standard procedures. Samples were collected from four bakeries coded as: A, B, C and D. Alkaloids, glycosides, steroids and saponins were present in all samples. Flavonoids were only present in samples obtained from bakery D. Quantitatively, phytochemical composition ranged from 0.08±0.00 mg/100g glycoside in samples from bakery A to 3.76±0.00 mg/100g alkaloids also in samples from bakery A. Trace metal analysis indicated that copper was only detected in samples from bakery B, and that iron levels were less than 0.009 mg/100g in all the samples, while tin was < 0.001 mg/100g in samples from bakery A and was not detected in samples from bakeries B, C and D. The levels of potassium bromate analysed by the congo red oxidation method in all the samples ranged from 6.66±0.00 to 52.19±0.00 mg/kg. With crystal violet oxidation method, they ranged from 5.09±0.00 to 58.36±0.01 mg/kg. Proximate composition ranged from 0.03±0.00 fiber in samples from A, C and D to 73.38±0.00% CHO in samples from C, while the calorific values ranged from 280.11±0.00 to 359±0.00 kcal in all the samples. Anti-nutrient composition ranged from 0.21±0.00 mg/100g tannin in samples from B to 1.68±0.00 mg/100g HCN in samples from C. Essential mineral composition ranged from 0.01±0.00 mg/100g phosphorus and sodium in samples from A and D to 1.89±0.00 mg/100g calcium in samples from B. Vitamins composition ranged from 0.19±0.00 mg/100g vitamin B2 in samples from D to 4.62±0.00 mg/100g vitamin C in samples from C. The bread samples were to some extend nutritive. The anti-nutrients and trace metals in the bread were below the levels that could cause toxicity in humans, except that the bread contained potassium bromate (banned chemicals that are hazardous to human health).