1. EFFECT OF EGG WHITE PRE-TREATMENTS ON ANTIOXIDANT ACTIVITY OF ITS HYDROLYSATE.
- Author
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Astri Suryani Prawulanari and Jirawat Yongsawatdigul
- Subjects
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EGG whites , *CHRONIC kidney failure , *IRON ions , *NUTRITIONAL value - Abstract
Egg white is considered as one of the best food proteins and hydrolysis can be applied to increase its nutritional value and reveal antioxidant activity. Low molecular weight of egg white hydrolysate was also beneficial for the chronic kidney disease (CKD) sufferers. However, hydrolysis of egg white protein typically results in relatively low yield. Thus, pre-treatment methods to increase yield of hydrolysate should be sought. The objective of this research was to compare the use of ultrasound, microwave, and steam sterilization (121°C) prior to hydrolysis of egg white by 10% (w/w protein) Alcalase on degree of hydrolysis (DH) and antioxidant activity of the hydrolysate. Ultrasound at intensity of 41.5 W/cm² applied to boiled egg white was found to produce hydrolysate with the highest DH of 45.4%. Antioxidant activities of egg white hydrolysate were examined by 2, 2'-azinobis- (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP), and ferrous ion chelating capacity (FICC) assays. Raw egg white subjected to sterilization for 5 min resulted in the hydrolysate exhibiting the strongest ABTS radical scavenging activity with approximately 64% inhibition. In addition, 30-min steam sterilization the most powerful pre-treatment yielding peptides with FRAP of 22 µM Trolox equivalence. Boiled egg white subjected to ultrasound at intensity of 41.5 W/cm² obtained hydrolysate with FICC of 1800 µM EDTA equivalence. Since there were several measured parameters, and pre-treatment methods affected these parameters differently. [ABSTRACT FROM AUTHOR]
- Published
- 2022