Materials Hazelnuts were purchased at a local market in
Karaj, Iran in November of 2012. The kefir grains used in
this study were obtained from a household in Tehran (Iran)
in September of 2012. These grains were sub-cultured in
milk at 20oC with twice or thrice weekly transfers to
sterilized cow’s milk before use in a main culture. Cheese
whey was also obtained from a semi-industrial dairy product
pilot plant located on the campus of the Agriculture and
Natural Resources College of Tehran University in Karaj,
Iran. All chemicals used were of analytical grade and were
purchased from Merck Chemical Co. (Darmstadt, Germany)
and Sigma-Aldrich Co. (St. Louis, MO, USA).