Effect of processing methods on the nutritional values and anti-nutritive factors of <i>Adenanthera pavonina</i> L. (Fabaceae) seeds

Abstract

This research aimed at determining the effect of processing on the nutritional and anti -nutritional values of “food tree” [Adenanthera pavonina L. (Fabaceae)] seeds, a highly nutritional and underutilized legume. The seeds were separated into three groups namely, boiled, roasted and raw. Quantitative analysis was carried out to measure their proximate, minerals, vitamins and anti -nutrients compositions. Analysis of variance was used to analyze the treatment groups and Duncan’s multiple range tests to determine significant difference at P ≤ 0.05. The results show that processing significantly affected the nutritional and anti -nutritional constituents. The values for proximate composition in the raw, roasted and boiled seeds were: proteins (15.79±0.04, 18.86±0.02 and 23.25±0.02, respectively), carbohydrates (56.60±0.02, 54.89±0.02 and 52.05±0.02 respectively), fat (9.78±0.02, 11.70±0.02 and 11.40±0.02, respectively), crude fibre (9.80±0.04, 9.70±0.04 and 5.85±0.02, respectively), moisture (3.88±0.03, 0.10±0.02 and 3.20±0.02, respectively) and ash (4.03±0.01, 4.75±0.02 and 4.25±0.01, respectively). The values for mineral compositions in the raw, roasted and boiled se eds were: calcium (25.61±0.34, 30.34±0.02 and 80.88±0.02, respectively), magnesium (18.97±0.01, 22.76±0.01 and 60.68±0.02, respectively), phosphorus (7.00±0.06, 6.40±0.15 and 5.80±0.10, respectively), potassium (3.31±0.00, 2.43±0.02 and 4.23±0.02, respectively) and iron (0.41±0.02, 0.41±0.01 and 1.23±0.01, respectively). The values for vitamin compositions in the raw, roasted and boiled seeds were: β carotene (1458.33±0.01, 416.67±1.20 and  416.67±0.08, respectively) and vitamin E (22.50±0.02, 9.24±0.02 and 12.69±0.01, respectively). The mean values for anti-nutrient compositions in the raw, roasted and boiled seeds were: tannin (1.21±0.00, 0.049±0.00 and 0.15±0.00, respectively), phytate (5.16±0.02, 3.50±0.01 and 1.50±0.02, respectively), oxalate (0.34±0.00, 0.13±0.00 and 0.11±0.00, respectively), cyanide (1.17±0.00, 0.95±0.00 and 0.32±0.00, respectively) and trypsin inhibitor (0.92±0.01, 0.36±0.01 and 0.90±0.01, respectively). The results show that processing changed the nutritional constituents and reduced the anti-nutrients in the seeds of A. pavonina and boiling proven to be the best processing method.

Key words: Processing, techniques, nutritional, anti-nutritive, Adenanthera  pavonina, seeds.