Download Eicosapentaenoic Acid(EPA), Docosahexaenoic

Eicosapentaenoic Acid(EPA), Docosahexaenoic Acid (DHA) Levels
and Microbiological Stability of Yoghurt Supplemented with
Microalgae Nannochloris spp.
A. Sibel Akalın1 Özlem Tokuşoğlu2 Necati Akbulut1 Sule Aycan3
1
Ege University, Faculty of Agriculture, Department of Dairy Technology, 35100,
Bornova, Izmir, Turkey
2
Celal Bayar University, Akhisar M Y. O., 45200, Manisa, Turkey
3
Celal Bayar University, Department of Chemistry, 45200, Manisa, Turkey
Microalgal biomass has been utilized for many years in human nutrition due to its high
protein and nutraceutical content such as Eicosapentaenoic acid EPA (20:5n-3),
Docosahexaenoic acid DHA (22:6n-3). In addition, the growth of yogurt starter bacteria
in milk is promoted by microalgae extracellular products. The objectives of this study
were to utilize the microalgae Nannochloris spp. as a potential yogurt supplement and
natural food additive, to investigate the effect of Nannochloris spp. on the growth of
yogurt starter bacteria, and to determine the EPA and DHA levels of new yogurt product
during storage at 4 °C for 35 days. Nannochloris spp. starter cultures were obtained
from the Culture Collection of Algae and Protozoa, Dunstaffnage Marine Laboratory,
Scotland, UK. The isolation of microalgae from cultures was done in the solid state via
the agar method at Pinar Deniz A.S., Izmir, Turkey. Yogurt starter culture was obtained
from Chr. Hansen A/S, Hørsholm, Denmark. Yogurt manufacturing process was done in
the Ege Univ., Dept. of Dairy Technology, Izmir. Microbiological analyses and the EPA,
DHA contents of yogurt samples were performed at regular intervals. The EPA and
DHA contents were analyzed using a 30-m (with 0.20 microm. film tickness), 0.25-mminside-diameter WCOT fused-silica Supelcowax-10 capillary column installed on a
Hewlett-Packard 5890 gas-liquid chromatography (GC) with a flame ionization detector
(FID). The new product was standardized and the methods used were quick, sensitive,
and repeatable. The Nannochloris spp. biomass had a beneficial effect on the survival
of yogurt starter bacteria during storage (P < 0.01).