A cooling experiment using a small-scale tank with conical bottom has been conducted in order to analyze the cooling characteristics of a cream cooling storage tank, and consider an improved impeller. A cream-like liquid having viscosity adjusted with carboxymethylcellulose (CMC) was used as the test liquid. For the stirring impeller, a special anchor impeller was employed, which was equipped with blades which scrape off the tank walls at the upper part, and blades which scrape up from the bottom at the lower part. The effects on cooling rate have been measured for 4 impeller shapes and their rotational directions. The average temperature profile index I-TP and the upper/lower temperature difference profile index I-DTP are defined and used to evaluate cooling rate and uniformity inside the tank. As a result, it has been found that, with pressing by the upper blades and scraping up by the lower blades, an impeller with a 90 degrees phase difference between the upper and lower blades is superior. When this result is applied to the design of an actual manufacturing tank, and comparative tests are conducted on rotational direction, the results are as expected based on the results with a small-scale experimental tank, and these results can be expected to improve the product quality and production efficiency.