PHYSICOCHEMICAL AND MICROBIAL STUDIES OF BAKED BREAD SAMPLES USING DIFFERENT IMPROVERS AS REPLACEMENT FOR POTASSIUM BROMATE

Abstract

The problem of using potassium bromate (classified as a carcinogen) as improver in bread making has led to a search for its substitute. The flour which was bought from the Oja-oba Market, Akure, Ondo State, Nigeria was mixed with four different improvers each in varying concentrations. Twelve different bread samples were baked and studies were carried out on the baked samples. Generally, the results showed that there are possible replacements for potassium bromate in baking products. Therefore this work involved the proximate composition, mineral analysis; physicochemical properties, sensory evaluation, specific loaf volume and microbial analysis of bread samples were analyzed using standard methods. The pasting properties were also studied using the rapid visco analyzer. The proximate composition (%) of the bread samples revealed that the mean and standard deviation of the samples ranges between (16.54 + 0.33) in Sample MA 2 and (26.38 + 2.66) for moisture content in sample GB. The highest fat content was recorded in sample B (25.42 + 1.34) while the lowest fat content was recorded in Sample GB (10.98 ± 0.41). The highest carbohydrate content (%) was recorded in sample TA 2 (55.66 ± 1.90) and the lowest in sample B (33.93 ± 0.42). The mineral analysis revealed that the calcium content ranges between 0.009mg/100g in Sample GB to 2.128mg/100g in Sample CA 2. The pasting parameters studied was breakdown, paste viscosity, gelatization temperature, retrogradation and pasting time. Sample GB records the lowest gelatization temperature indicating that it will require less energy in baking than others while sample N (the control without any improver) will require the greatest energy in baking than other samples. The sensory evaluation revealed that sample MA1 has the most preferred color, samples B and N not significantly different in texture while sample CA 1 was the most preferred in overall acceptability. The microbial analysis revealed that there was no microbial growth on all the cultured plates for all the bread samples. Generally, the results showed that there are replacements for potassium bromate in baking products.