Juan Pablo Chavez Garcia | ALES Graduate Seminar

A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc course-based Final Exam Seminar by Juan Pablo Chavez Garcia. This seminar is open to the general public to attend.

Thesis Topic: Subcritical water hydrolysis of fava bean concentrate to obtain bioactive compounds

MSc with Dr. Marleny Aranda Saldana.

Seminar Abstract:

Pulses like fava bean are food commodities worldwide. They can be fractionated resulting in fava bean concentrates that can be hydrolyzed to bioactive compounds, including peptides and essential amino acids. Subcritical water processing is an environmentally friendly alternative that can improve the biological value of fava bean concentrate by increasing the contents of bioactive peptides, amino acids and minerals. The main objective of this study was to assess the effect of subcritical water processing conditions (temperature, pressure and time) to obtain fava bean hydrolysates with antioxidant activity. Hydrolysis reactions were carried out in a Parr 4590 system. Fava bean concentrate solutions were treated at 160-220°C and 50 or 100 bar for 10-60 min. Hydrolysates obtained were characterized for physicochemical properties (pH, conductivity, colour, etc), mineral and phosphate contents and antioxidant capacity using the FRAP and DPPH methods. The highest yield (80.3±0.2% w/w) of hydrolysates was obtained at 180°C and 50 bar for 40 min. Subcritical water processing increased the phosphate (401±14 mg/kg hydrolysate) and calcium (57.6±1.1 mg/kg hydrolysate) contents due to the hydrolysis of phytic acid, which is responsible for the low availability of minerals such as phosphorous and calcium in fava bean concentrate. Subcritical water influenced the pH and conductivity values. Finally, subcritical water proved to be effective to produce fava bean hydrolysates with high antioxidant activity (129.1±0.9 meq ascorbic acid and 91±1% of DPPH inhibition). The hydrolysates can be further dried and used as antioxidants, emulsifiers and gelling agents with high digestibility in the food industry.