Comparison between the nutritional quality of flour obtained from raw, roasted and fermented sesame (Sesamum indicum L.) seed grown in Nigeria.

BACKGROUND: The most common form of utilization of sesame seed is its roasting, which supplies nutrients to the diet. Therefore, in view of the nutritional values of sesame seeds, the present study aimed at investigating the effect of roasting and fermentation 011 the nutritional quality of sesame flour.

MATERIAL AND METHODS: Nigeria grown white sesame seeds (NC'RI-98-60) were collected from National Cereal Research Institute (NCRI). Badegi. Nigeria. The seeds were divided into three portions, and treated as raw. roasted and fermented sesame seeds respectively. Each of the samples was milled, sieved and analysed for chemical composition using standard methods. Animal studies were used to evaluate the raw and processed sesame in terms of nutritional and histopathological qualities.

RESULTS: The ranges of proximate contents from sesame were: protein 15.4-26.5 g/100 g. fat 52.4-62.8 g/100 g, crude fibre 3.34-3.89 g/100 g. ash 3.93-6.78 g/100 g. carbohydrate 11.7-13.4 g/100 g and energy value 550.7-593.7 kcal/g. Among the minerals, calcium was highest (464-567 mg/100 g) followed by phosphorus (442-508 mg/100 g). magnesium (399-455 mg/100 g) and potassium (336-489 mg/100 g). Total essential amino acid was within the range of 26.66-32.73 mg/100 g and these values were higher than FAO/WHO dietary requirement for infant and adult. Fatty acid profiles of raw. roasted and fermented sesame showed a predominance of oleic acid (46.43%, 44.20%, and 43.16%, respectively) followed by linoleic acid (36.76%. 39.02%, and 39.67%); while the least was behenic acid. The unsaturated/saturated fatty acid ratio ranges between 5.01-5.13. Phytate and oxalate concentrations of fermented sesame were significantly reduced than other food samples. In general, fermented sesame was found to have to have better nutritional quality as indicated by rat growth response. Correspondingly, the Food Efficiency Ratio (FER) value of 0.16 was higher than raw and roasted sesame respectively. Significantly higher Protein Efficiency Ratio (PER) value was also obtained for fermented sesame. The organ to body ratios of the test animals were influenced by treatments as recorded on heart, kidney, spleen, liver and pancreas.

CONCLUSION: The present study investigated the effect of roasting and fermentation 011 the nutritional quality of sesame flour. The findings showed that roasting and fermentation could enhance the nutritional quality of sesame seeds without detrimental effect 011 human.