Possibility of Concentrating Milk Enriched with Lemongrass (Cymbopogon) as a Preservative using Ultrafiltration Technology

Abstract

Background: This study aimed at the possibility of concentrating milk in the laboratory using ultra-filtration technology instead of the traditional evaporation method that is still used in Iraq. Methods: Therefore, 5 litres of raw, cow milk were taken from a reliable source and two different concentrations of lemongrass were added as a preservative to observe the changes occurring during concentration, chemically and microbial. The best conditions were found to concentrate the milk 2.7 once and improve it over many days with the addition of lemongrass extract as a preservative. A material with a flat membrane polyethyle-solphen with a measurement of 10 kdalton (Snyder USA) was selected. Throughout the duration of the more than three-hour experiment, the measurements were taken. Two sets of data were examined: in the first set, the flow rate was varied between 0.15 and 0.25 L/min while the trans membrane pressure (TMP) was kept constant at 2 bar. The value of 0.15 L/min was determined to be the ideal flux. In the second group, the trans membrane pressure was varied between 0.5 and 1,2 bar while the flow rate was kept constant at 0.15 L/min. At TMP 2 bar, the ideal flux value was discovered at 35°C, the permeate flux was around 5-7 L/m2.hr. Result: It was found the change of the total solid and protein were excellent percentages with time of filtration. The total number of bacteria at both concentrations decreased significantly (p less than 0.05) in the biological test results.