Effect of Drying Methods on Odorous Compounds and Antioxidative Activity of Gelatin Hydrolysate Produced by Protease from B. amyloliquefaciens H11

Abstract

Gelatin hydrolysates with antioxidative activity produced by protease from Bacillus amyloliquefaciens H11 with different hydrolysis times were prepared. Alpha-amino group content and antioxidative activities increased with increasing hydrolysis time (p < 0.05). When gelatin hydrolysate prepared with hydrolysis time of 3 h (GH-3H) was subjected to freeze drying and spray drying, the powder obtained from spray drying showed a decrease in antioxidant activity as measured by DPPH and ABTS radical scavenging activities, ferric-reducing antioxidant power, and metal chelating activity. Spray-dried gelatin hydrolysate (GH-3H-SD) showed higher whiteness with lower fishy odor and off-odor associated with fermentation. This was concomitant with the decreases in several odorous compounds in the sample, except for nonanal, which was higher in comparison with the powder obtained by freeze drying. Thus, spray drying could be an effective drying method to improve color and reduce undesirable odor of gelatin hydrolysate.

Keywords:

• Antioxidative activity
• B. amyloliquefaciens H11
• Gelatin hydrolysate
• Odor
• Spray drying

Notes

Different lowercase letters within the same column indicate significant differences (p < 0.05).

Different uppercase letters within the same row indicate significant differences (p < 0.05).

Different lowercase letters within the same row indicate significant differences (p < 0.05).

*Mean ± SD (n = 3).

Different lowercase letters within the same column indicate significant differences (p < 0.05).

ND: not detectable.

Different lowercase letters within the same column indicate significant differences (p < 0.05).

Different uppercase letters within the same column under the same medium indicate significant differences (p < 0.05).