Today, there is high regard for foods with positive effects on human health as well as nutritional value. Probiotic dairy products -- especially yogurt -- are popular all over the world. In this study, potato and rice starch in yogurt were examined to understand the effect on growth and survival rates of the probiotic bacteria Lactobacillus Acidophilus at concentrations of 0.1%, 0.5 % and 1%. Each of these three concentrations was held at 4° C for 21 days and then measured for pH, acidity, and percentage of syneresis. Probiotic bacteria counts were then compared with the control sample, a probiotic yogurt without prebiotic substances. -- (That last sentence isn't really logical as written...)

Today, food products which have positive effects on human health in addition to nutritional value are highly regarded. Probiotic dairy products, especially yogurt, are popular the world. In this study potato and rice starch at the concentrations of 0.1%, 0.5 % and 1% in yogurt were examined to understand each concentrations effect on growth and survival of the probiotic bacteria Lactobacillus Acidophilus. The samples produced in three replications and maintained at 4 ° C during 21 days ( OR during 21 days of storage at 4 ° C ) were evaluated in terms of pH rate, acidity,and syneresis percentage. Probiotic bacteria counts were then compared with the control sample. i.e. probiotic yogurt without prebiotic substances. - add what you hope to accomplish by looking at the results here- some minor grammar issues and a few places where it was better to just end the sentence instead of using a comma/and. I'm no expert though so take this version with a grain of salt