Treatment of onion skin waste using dielectric barrier discharge cold plasma processing

Senguler B., Kırkın Gözükırmızı C., Donmez H., Unal S.

Food Science and Nutrition, vol.12, no.10, pp.8387-8393, 2024 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 12 Issue: 10
  • Publication Date: 2024
  • Doi Number: 10.1002/fsn3.4448
  • Journal Name: Food Science and Nutrition
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Agricultural & Environmental Science Database, Food Science & Technology Abstracts, Greenfile, Directory of Open Access Journals
  • Page Numbers: pp.8387-8393
  • Keywords: antioxidant activity, cold plasma, color, microbial quality, onion skin, total phenolic content
  • Istanbul Gelisim University Affiliated: Yes

Abstract

Onion skin constitutes a major part of industrial food waste, and cold plasma technology can be employed in the treatment of onion skin. Onion skin waste was ground and exposed to dielectric barrier discharge cold plasma (DBDCP) at 40 kV for 10 or 20 min. Samples that were not DBDCP treated were used as the control. The changes in the color, microbial load, total phenolic content (TPC), and antioxidant activity of the onion skin waste upon treatment were evaluated. An increase in the b* and C* values of the onion skin powder (OSP) was obtained after the DBDCP treatment. The DBDCP process also decreased the total mesophilic aerobic bacteria and yeast–mold counts of the OSP by up to 0.92 and 0.97 log cfu/g (colony-forming units per gram), respectively. In addition, the TPC and antioxidant activity, as determined by 2,2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and ferric-reducing antioxidant power (FRAP) methods, were increased for up to 59% and 28%, respectively, depending on the treatment time. In conclusion, the findings of the study show that using DBDCP processing in the treatment of onion skin waste can reduce microbial count while enhancing TPC and antioxidant activity.