Research on the losses of nutrients of yoghurt during the production of straned yoghurt

IV ABSTRACT RESEARCHS ON THE LOSSES OF NUTRIENTS OF YOGHURT DURING THE PRODUCTION OF STRAINED ( TORBA ) YOGHURT Milk is a white liquid that is secreted from mammary glands of cow's, sheep's, goat's and buffalo's and has special taste, flavour and viscosity. It is a product that can be easily spoiled. While some amount of produced milk is consumed as drinking milk, an enourmous amount of it is evaluated as milk products. So it is benefited from valuable foodstuff for a longer time and according to human deligth, different dairy products are produced. One of these products is yoghurt. Yoghurt is readily spoiled due to the conditions of storage and preservations because of 85 percent water in it. That is why human being has attempted to produce differents kinds of yoghurts which is kept fresh for a longer time. Strained yoghurt which is known as torba yoghurt in Turkish society is a very important and very common foodstuff. It is traditionally produced in the middle and small plants and by the people who live in urban locations. In this study, the losses of nutrients during the production of strained yoghurt by conventional method were investigated. The samples of milk were taken from a small dairy plants in Manisa. After normal yoghurt had been produced from cow's milk, it was strained for 12 hours in cloth bag made of bezayağı that contains 15 x 22 fibre / cm2. The nutrients in both normal yoghurt and whey had been determined and the losses of nutrients during the production of strained yoghurt were calculated as follows; thiamin % 51,80, riboflavin % 60,49, protein % 7,18, fat % 0,77, lactose % 71,14, sodium % 70,22, potassium % 68,16, calcium % 65,64 and phosphour % 50,21 in normal yoghurt. The least loss among the amino acids is % 2,24 tyrosin and the most loss is % 1 1,38 in histidine. Among all nutrients the loss of lactose was found to be the highest (% 71,14) and the loss of fat to be the lowest ( % 0,77 ).