New insulation material and special paper keeps tonkatsu crumbed pork cutlets at 60 C and crisp even after 30 minutes

Professor Koichi Tozawa of Shibaura Institute of Technology’s College of Engineering and Design and Tonkatsu Hamakatsu, a tonkatsu crumbed pork cutlet restaurant chain run by Ringer Hut, have jointly developed a container that keeps takeout tonkatsu hot and crispy for at least half an hour. The new thermal insulation material and special paper used in the container allows customers to eat tonkatsu that tastes just like a freshly cooked cutlet served at a Tonkatsu Hamakatsu restaurant.

The restaurant chain has been using the box since December 7, 2018. The patent for this box is pending (patent application number: 2018-186656). 

Tonkatsu stays above 60 C after 30 minutes

Placing the new thermal insulation material underneath the cutlet and accompanying rice keeps the meal hot for longer

Thermal insulation material
The new insulation material is made from barley, a compact grain with a high heat retention capability. Previously, the restaurant chain placed tonkatsu in a container’s upper tier, which was kept warm by the heat of rice in the lower tier. The new box features the insulation material under the cutlet in the lower tier and under warm rice in the upper tier. This results in tonkatsu that is kept at over 60 C even after 30 minutes.  

Tonkatsu crumbs stay crisp for longer

Special paper for absorbing vapors placed over tonkatsu and sheet for absorbing excess oil and moisture placed underneath

Absorption sheet
Placing a special, vapor-absorbing paper over the tonkatsu and using a newly developed sheet that absorbs excess oil and moisture enables the crumbed cutlet to remain as crisp as one freshly cooked and served at the restaurant. 

Professor Tozawa researches and creates items when asked by companies in the manufacturing, service and other sectors. He received a request from Tonkatsu Hamakatsu, which wanted its popular tonkatsu takeout meals to taste more like the freshly served meals at the restaurant chain. Professor Tozawa and Tonkatsu Hamakatsu successfully developed the new container after conducting basic research and various experiments for well over a year.

SIT will continue to help create products that satisfy client companies and their customers.


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