Shiro Shoyu, or white soy (which has more of a beautiful golden sheen if truth be told) and is a touch lighter and sweeter, but far saltier than a regular shoyu. Shiro Shoyu has a higher ratio of wheat to soybeans in its production (somewhere close to 90:10) and is fermented for far less time - around three months - which contributes both to its flavour and visual appeal. 

The light colouring means it can be used when presentation is of particular importance - for example, letting the natural pink blush of sashimi tuna shine on the plate, or when creating a light consume style broth.