Clarification of pomegranate and strawberry juices: Effects of various clarification agents on turbidity, anthocyanins, colour, phenolics and antioxidant activity


Orhan Dereli B., Türkyılmaz M., ÖZKAN M.

FOOD CHEMISTRY, vol.413, 2023 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 413
  • Publication Date: 2023
  • Doi Number: 10.1016/j.foodchem.2023.135672
  • Journal Name: FOOD CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, EMBASE, Food Science & Technology Abstracts, Metadex, Veterinary Science Database, Civil Engineering Abstracts
  • Keywords: Anthocyanins, Bentonite, Gelatine, Hot-clarification, Kieselsol, Pomegranate juice, Strawberry juice, Turbidity
  • Ankara University Affiliated: Yes

Abstract

Effects of clarification on turbidity, anthocyanins (ACNs), colour, phenolics, ascorbic acid and antioxidant ac-tivity (AA) of pomegranate (PJ) and strawberry juices (SJ) were investigated. Cold-clarification was applied to PJ using only gelatine. For hot-clarification of both juices, bentonite, gelatine and kieselsol were used. Moreover, pectolytic enzyme was added to SJ that contains pectin. Depectinization caused an increase in colour density of SJ and bentonite treatment resulted in low turbidity (9.5 NTU). However, gelatine and kieselsol significantly reduced ACN content (15%) and increased turbidity (70.1 NTU). In PJ, no step during hot-clarification provided low turbidity (93.2-162.0 NTU), while relatively low turbidity (28.7 NTU) and anthocyanin loss (9.8%) was achieved during cold-clarification. Hot-clarification of SJ showed no effect on AA and phenolics, while cold-clarification of PJ reduced both to a limited extent. Therefore, depectinization and bentonite treatment are recommended for hot-clarification of SJ and gelatine for cold-clarification of PJ.