Fortification of milk with plant extracts modifies the acidification and reducing capacities of yoghurt bacteria

Alwazeer D., BULUT M., Tunçtürk Y.

INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, vol.73, no.1, pp.117-125, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 73 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.1111/1471-0307.12643
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, ABI/INFORM, Agricultural & Environmental Science Database, BIOSIS, CAB Abstracts, Food Science & Technology Abstracts, INSPEC, Veterinary Science Database
  • Page Numbers: pp.117-125
  • Keywords: Acidification capacity, Reducing capacity, Milk, Plant extracts, Yoghurt bacteria, ANTIOXIDANT, VIABILITY, STORAGE, CHEESE, PH
  • Van Yüzüncü Yıl University Affiliated: Yes


The acidification and reducing capacities of yoghurt bacteria were evaluated in different plant extract-enriched milk samples. The milk samples enriched with thyme and grape seed extracts exhibited the highest values of acidification capacity for Lactobacillus delbrueckii subsp. bulgaricus (LB) (0.0065 pH unit/min) and Streptococcus thermophilus (ST) (0.0068 pH unit/min). The highest values of reducing capacity were observed in thyme (-0.98 mV/min), grape (-1.92 mV/min) and green tea (-0.75 mV/min)-enriched samples for LB, ST and mixed culture of LB + ST, respectively. The fortification of yoghurt with plant extracts modified the acidification and reducing activities of starters, thus changing the fermentation time and quality attributes of the product.