Evaluation of Physicochemical, Functional and Morphological Characteristics of Starch Extracted from Defatted Conophor Seed (Tetracarpidium conophorum)

Aim: Starch is the main carbohydrate store for numerous crops and each crop has distinct and unique characteristics. This study was aimed at investigating the physicochemical composition, functional properties and morphological characteristics of starch extracted from defatted Conophor seed flour.

Place and Duration: Food Chemistry Laboratory, Department of Food Science and Technology, and Biochemistry Laboratory of the Federal University of Technology, Akure, from March 2023 to September 2023.

Methodology: Conophor seeds were washed, shelled manually, oven dried, milled into coarse flour and then defatted using solvent extraction method with the use of a soxhlet extractor. The defatted flour was air dried and grounded into fine powder. Starch was extracted by sedimentation at pH 11.0 and then oven dried and grounded into powder. The physicochemical composition, functional properties and morphological characteristics of Conophor starch were studied.

Results: The physicochemical study shows that Conophor starch was abundant in carbohydrate (77.26%) but had a low protein (4.46%), fat (1.99%) and fibre (1.20%) content. Mineral content of the starch were high with calcium (194.17mg/g), copper (0.05mg/g), manganese (0.42mg/g), magnesium (4.26mg/g), iron (0.34mg/g), zinc (1.59mg/g), phosphorus (26.1mg/g), sodium (23.20mg/g) and potassium (37.13mg/g). The functional property of Conophor starch showed a high water absorption capacity (513.33%), oil absorption capacity (347.57%), emulsion capacity (45.48%), emulsion stability (50.00%), swelling index (246.67%), gelation capacity (12.00m/v) and low foaming capacity (12.69%) and foaming stability (3.26%). Conophor starch had a low pasting property with peak viscosity (14.00 RVU), final viscosity (16.00 RVU) and set-back viscosity (4.00 RVU).

Conclusion: The study showed Conophor starch to be a rich source of mineral which makes it suitable for use as a supplement and its functional property makes it capable to be used in some industrial processes. However, the low paste quality of the starch renders it unsuitable for use in food processes that requires high paste formation but may be considered suitable for use in non- food related industries.