Effect of germination and boiling on the phytochemical content of four Nigerian pulses

Abstract

Background: Nutritionally, pulses are good sources of protein, fibre, antioxidants, rich in iron, potassium and are excellent sources of folate. Bioavailability of micronutrients in plant-based diets to a greater extent could depend on pre-treatment.

Methods: Four Nigerian pulses namely cowpea, pigeon peas, lima beans and adzuki beans were obtained in north south and south-south zones of Nigeria. The pulses were pretreated (germinated and boiled) and the effects of the pretreatment on the phytochemical were assessed using standard methods.

Results: Germination significantly decreased the phytate content of the lima beans (22.25 to 13.18 and 9.40 to 9.2018mg/100g), lima and adzuki bean (24.72 to 23.07 and 13.00 to 2.30mg/100g). Germination increased the phenol content of the Cowpea (0.73 to 0.85mg/100g), pigeon pea (0.82 to 0.87mg/100g), lima beans (0.57 to 0.6718mg/100g) and adzuki beans (0.72 - 0.81mg/100g). However, none of the observed differences were statistically significant (p < 0.05). Only the phytate and saponin content of cowpea (22.25 - 8.24 and 9.40 to 3.20 and adzuki beans (24.72 - 14.01 and 13.00 to 10.10mg/100g). and the phytate content of pigeon peas and lima beans (14.83 to 12.36 and 13.76 to 6.59mg/100g) were significantly decreased (p < 0.05) by boiling.

Conclusion: Boiling is the most effective in reducing the concentration level of phytate, phenol and saponin content in cowpea, pigeon pea, lima beans and adzuki beans.

Keywords: Effect, germination, boiling, Nigerian pulses, flours