Degradation of antinutrient factors in runner bean (Phaseolus coccineus) seed in processing

B.Sc. Ibitayo Esther Adeniran, BSc

Master's thesis

Abstract:

Runner beans (Phaseolus coccineus) are a rich source of nutrition but are often limited by antinutrient factors like trypsin inhibitors, phytic acid, saponins, and α-galactosides, which reduce their nutritional value and consumer appeal. This research aims to address this by studying the effects of thermal and non-thermal treatments on antinutrient reduction in runner bean seeds. Specifically, it examines the impact of treatments on antinutrient levels, liquid-solid ratios in boiling, and functional properties of white and black runner bean seeds. Various parameters, including tannin content, phytic acid concentration, and saponin analysis, were assessed using established methodologies, and the data were subjected to analysis of variance using GENSTART, 8edition 2016. Least significance LSD was also used to compare treatment means (P < 0.05). The investigation revealed significant reductions in antinutrient factors following both thermal and non-thermal treatments. Initial tannin decreased notably after soaking, from 0.01 to 0 for white seeds and from 0.33 to 0.20 for black seeds. Similarly, initial tannin concentrations decreased post-soaking, from 1.45 mg/ml to 0 mg/ml for white seeds and from 39.41 mg/ml to 23.93 mg/ml for black seeds. Saponin levels also decreased significantly during soaking, with concentrations dropping from 0.44 mg/ml to 0.04 mg/ml for white seeds and from 0.07 mg/ml to 0.02 mg/ml for black seeds. Additionally, there was a notable decrease in phytic acid concentration after soaking, particularly at higher soaking ratios. For unsoaked seeds, the phytic acid concentration was 3.84 mg/ml for white seeds and 3.76 mg/ml for black seeds, while after soaking at a ratio of 5:1, these concentrations decreased to 2.47 mg/ml for white seeds and 2.68 mg/ml for black seeds. This study underscore the effectiveness of soaking in reducing antinutrient content, thereby enhancing the nutritional quality of runner beans. The functional properties of runner bean seeds that indicates their water absorption, foaming, and emulsification capacities influenced by processing techniques was also explored. These findings are valuable for the food industry, offering insights into the development of bean-based products with enhanced nutritional profiles and functional attributes.

Keywords

Runner bean, Antinutrients, Thermal and non thermal treatment, Food industry, Nutrition, Saponin, Trypsin inhibitors, Phytate, Analysis of variance, mean startndard deviation, Tannins

Language used: English

Date on which the thesis was submitted / produced: 28. 4. 2024

Thesis defence

• Date of defence: 3. 6. 2024
• Supervisor: Ing. Olga Leuner, Ph.D.
• Reader: Ivo Doskočil, Ph.D.

Czech University of Life Sciences Prague

Faculty of Tropical AgriSciences

Master programme:
Agri-food Systems and Rural Development