Daifuku is a pounded rice cake stuffed with sweet bean jam. Yukimi is an adjective that means viewing snow, so the whole name implies eating a traditional rice-bean sweet while looking at snow scenery. Daifuku can be eaten and enjoyed all-year round, but since it is made from rice which is steamed and smashed into pastry form, it can harden in just a few days or when the ambient temperature lowers.

Associate Akuzawa with her student.	Two SV-10's are measuring viscosity simultaneously.

Associate Professor Akuzawa explained, “Softness and stickiness are two things that are inseparable, and it is very difficult to treat softness and stickiness independently of each other, especially at all temperatures.” She was referring to the pastry-like crust or skin that covers this ice cream. (The next day I ran to a nearby convenience store and bought three packs of Yukimi Daifuku. On the package it says to keep it under 10 degrees below zero. I found the thin white skin very soft at such a low temperature and it had no stickiness at room temperature while I was observing it. Its softness stayed the same without becoming sticky at the different temperatures it went through progressing from freezing temperature to eating temperature. I then realized what Associate Professor Akuzawa meant to say. I kept Yukimi Daifuku in the freezer thinking I would take photos next day, but when I went back to fetch them I couldn't find them anywhere. Sawa, my daughter said, “Oh, was it you that bought them?”)

When we visited Associate Professor Akuzawa for an interview at her laboratory, she greeted us in a typical white laboratory uniform and led us into a small room adjacent to the main laboratory, where two students of hers were measuring viscosity. We could not wait to ask about the SV-10's those two students were using right behind us. “They are measuring various food materials at different temperatures to judge the right time for serving them. As food changes its characteristics in a short time, we use two SV-10's to measure the viscosity of a material at two different stages simultaneously. For instance, we collect data as to how the viscosity of convenience foods change rapidly after it is unpacked. For that we use the same material at two different temperatures simultaneously so the differences in viscosity are only attributable to temperature changes. The students are collecting a lot of data by using SV-10's that will be used for their graduation dissertation papers.” “Speedy measurement and accurate low viscosity measurement are great plus to our experiments.” “Students enjoy measuring viscosity of many different ingredients,” she added.

Beforehand I had heard that she was using our WinCT-Viscosity software in her classroom by showing the viscosity graphs projected onto a screen. She found it very effective in showing how viscosity changes as temperature changes as it shows phenomena in real time in front of the class.

She added that there are a lot of experiments taking place for food for elderly people or people who experience difficulty in swallowing. “We tend to assume elderly people appreciate soft and tender food. But people remember how the food's texture was, thus unless the food gives feeling of texture similar to what they remember, the same taste does not give the kind of satisfaction they want to have. That means making food softer and more tender for elderly people is not enough. That is why the viscosity measurement becomes important in order to give the food texture that stays in their memory. Another important subject of concern is to make food softer without increasing its stickiness that causes swallowing problems.” At this time the story of Yukimi Daifuku came up. She also explained that in serving or designing food for a hospital or a home for the elderly, to understand how the food's viscosity and stickiness change as time passes is of vital importance. Ideally the texture of a food should stay constant regardless of any temperature change.

It has been a revelation to me that the viscosity measurement of foods is such an important element in food science and research. Associate Professor Akuzawa said she would be going to the University of Iowa for a year. I can easily imagine her presenting her research and findings to new students and faculty she will encounter there by using the SV-10 and WinCT-Moisture in the class. I am sure we will soon find more break-through foods like Yukimi Daifuku for which our SV-10 has collected data.

The packaging for Yukimi Daifuku, which contains two pieces of ice cream covered with a thin pastry-like skin, which stays soft without getting sticky at all temperatures. The skin or crust of the traditional Daifuku is made of rice-cake, that hardens very quickly and its texture changes at different temperatures.