Enzymatic Hydrolysis of Tenebrio molitor (Mealworm) Using Nuruk Extract Concentrate and an Evaluation of Its Nutritional, Functional, and Sensory Properties

• Published in: Foods Vol. 12; no. 11; p. 2188
• Main Authors: Chewaka, Legesse Shiferaw, Park, Chan Soon, Cha, Youn-Soo, Desta, Kebede Taye, Park, Bo-Ram
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29-05-2023; MDPI
• Subjects: alcalase; Amino acids; Angiotensin; Biological activity; Enzymes; Feeds; Fermentation; flavourzyme; Food science; Hydrolysates; Hydrolysis; Insects; nuruk; Nutritive value; Peptides; Peptidyl-dipeptidase A; protease; protein hydrolysate; Proteins; Reagents; Saltiness; Sensory properties; Sodium; Subtilisin; Sweetness; Tenebrio molitor; Vantaa Finland; South Korea; United States > US; Finland; protease; nuruk; Tenebrio molitor; alcalase; flavourzyme; protein hydrolysate
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods12112188

Enzymatic protein hydrolysis is a well-established method for improving the quality of dietary proteins, including edible insects. Finding effective enzymes from natural sources is becoming increasingly important. This study used nuruk extract concentrate (NEC), an enzyme-rich fermentation starter, to produce protein hydrolysate from defatted
(also called mealworm, MW). The nutritional, functional, and sensorial properties of the hydrolysate were then compared to those obtained using commercial proteases (alcalase and flavourzyme). The protease activities of the crude nuruk extract (CNE), NEC, alcalase, and flavourzyme were 6.78, 12.71, 11.07, and 12.45 units/mL, respectively. The degree of hydrolysis and yield of MW hydrolysis by NEC were 15.10 and 35.92% (
/
), respectively. MW hydrolysate was obtained using NEC and had a significantly higher free amino acid content (90.37 mg/g) than alcalase (53.01 mg/g) and flavourzyme (79.64 mg/g) hydrolysates. Furthermore, the NEC hydrolysis of MW increased the antioxidant and angiotensin-converting enzyme inhibitory activity, with IC
values of 3.07 and 0.15 mg/mL, respectively. The enzymatic hydrolysis also improved sensory properties, including umaminess, sweetness, and saltiness. Overall, this study found that the NEC hydrolysis of MW outperformed commercial proteases regarding nutritional quality, sensory attributes, and biological activity. Therefore, nuruk could potentially replace commercial proteases, lowering the cost of enzymatic protein hydrolysis.