Evaluation of Lactose in Milk and Dairy Products

Milk is an emulsion containing fat, protein, carbohydrate, vitamins, minerals and water. Lactose is the main carbohydrate presented in milk and dairy products. This sugar is composed by one unit of glucose and one of galactose. Metabolism of lactose depends on enzyme lactase which hydrolyzes this sugar. In some cases, lactase may be absent or an insufficient quantity in human body. Deficiency in lactase production causes numerous symptoms such as diarrhea; abdominal pain and bloating that characterize lactose intolerance. The aim of this work was to evaluate concentration of lactose in milk and dairy products to determine the effect of the processing and to calculate the quantity of each product which can be consumed without symptoms in lactose intolerant. Results obtained show lactose concentration of 4.42% w/v in Milk; 3.5% w/w in Minas cheese; 9.9%w/v in condensed milk and 4.76%w/v in yogurt. Portion innocous ranged from 60 to 170 mL depending on each product.