Biotechnological processing procedures of collagen-containing raw materials for creation of functional foods - Anna V. Shсhekotova, Irina S. Khamagaeva, Vladimir Zh. Tsyrenov, Natal'ya V. Darbakova, Sof'ya N. Khazagaeva (Известия вузов: Прикладная химия и биотехнология)