International Journal of Scientific and Research Publications, Volume 4, Issue 11, November 2014 1 ISSN 2250-3153 www.ijsrp.org Effect superheated steam on physical and lipid stability of reconstituted whole milk powder Ghazwan Mahdy * , Tajul A. Yang ** * Department of food science, School of Agricultural, Tikrit University, Tikrit Salah- Alddin Iraq. ** Food Technology Division, School of Industrial Technology, University Sains Malaysia, Minden 11800 Pulau Pinang Malaysia. Abstract- Milk powders are considered as food ingredients and its intervention in the manufacture of many foods and all this exposed to high temperatures when it cooked. Many of changes accrue in physical and chemical properties of milk. In this study the changes in physical properties color, viscosity, density, P H and lipid stability peroxide oxidation value (POV) and total free fatty acids (TFFA) was measured to reconstituted (WMP) whole milk powder in relation thermal treatment using superheated steam with different temperature and period time. The temperature ranged from 150-210 ° C for 5-25 min. The result for color showed in three different system (L, a, b). The superheated steam show lower different to color at the high temperature 210 ° C and long time 25 min compare with control . At the viscosity, density and P H the result of superheated steam showed clear differences at temperature 150 and 210 ° C at long time 25 min. About the lipid stability (POV peroxide oxidation value and total free fatty acids) the result of POV to superheated steam do not showed any significantly differences between sample heat treatment compare with control at 150-180 ° C and that indicates no any oxidation reaction occur between the fatty acids and molecule oxygen in superheated steam. The result of total free fatty acids content showed lower changer at the high temperature 210 ° C and long time 25 min but other sample no any significantly different show compare with control. All the result in this study showed stability of milk fat to reconstitute whole milk powder and that will be lead to maintain of nutrition value to milk fat during cooking. Index Terms- physical analysis, superheated steam, milk powder, lipid oxidation. I. INTRODUCTION ilk is one from the important products and can entered to manufacture many food because it has many properties to improve test and flavor with high nutritional value and it use in many food industry such as cake, biscuits, chocolate, caramel candy, famous Indian milk balls known as rasgulla and popular Indian sweet etc [1 ]. Milk has many compounds affected by temperature which can led to change sensorial quality to consumers which view of the color, viscosity and flavor [2 , 3 ]. Whole milk powder use to manufacture many food because it has large impact to suitability for confectionary [4 ]. The manufacture of milk chocolate it is usually preferred the powder milk product by roller drying. Effect heat treatment on the physical and chemical properties in whole milk powder was study from many researchers. Marie showed in his study that was many damage in physical properties when stored the milk at long time and also showed damage in the color that was cause by Millard reaction which occurred during the storage [4 ]. From other study the effect ultrasound with the temperature on the physical properties in sheep milk and the result were recorded changes in the viscosity, P H and density by different heat treatment with different time [5 ]. Increase of heat treatment on the milk cause increase of Millard reaction whereby Millard reaction was became very active with increase temperature [6 ]. Effect heat treatment and the storage on changes color in whole milk powder and the causes increase in color changes at high temperature and long storage that can causes damage in physical properties of product [7 , 8 ]. Many thermal methods use to process food and get good result with the least possible impact on the components of food like air oven, microwave and superheated steam oven. The superheated steam is steam that has temperature above the boiling point, that mean up the boiling point the steam will be formation than the steam convert to unsaturated steam than to superheated steam [9 ]. Superheated steam oven its new thermal method public now to cook and drying foods and it has many good advantage such as, high heat transfer capability, produces condensation heat on coming into contact with the food, provides no oxygen environment and can be obtained under normal pressure. Superheated was discover before 100 years ago but not development until 30 years ago specially in energy efficient [10 , 11 ]. Superheated steam uses to dry many products continent high fat that was to exhibit the lipid oxidation by use high temperature because has less oxygen and that it prevents formation hydroperoxide [10 ]. The objective of this study to studies effect of superheated steam on the physical changes and lipid oxidation in reconstitute whole milk powder by use different heat treatment and different time. II. MATERIAL AND METHOD Whole milk powder- The whole milk powder was supplied from Nestle company was choose (Nespray) type which purchase from the Tesco market in Penang city in Malaysia. The amounts of contents were following the standard milk powder which contented fat (28.2 g per 100 g) protein (23.6 g per 100 g) carbohydrate (39.9 g per 100 g). Reconstitute the whole milk powder- The reconstitute whole milk powder was followed instructions to the consumer listed on the package. The whole milk powder (WMP) was reconstitute by use (33) g from the powder milk and added (225) ml water after that shaking on the magnetic stirrer for (10) min, M