The tan foliage is probably last year's dead foliage. If the grass survived the winter, it should be starting to send up new, green foliage. It also should have been cut back to the ground long before this.

What zone are you in? Pampas grass is an evergreen grass and while it can be expected to have some dead fronds after winter, if the entire grass is a uniform dead-looking tan, chances are it may not have survived the winter cold. Since it is an evergreen, cutting back is optional, not necessarily a requirement, depending on your location and its appearance. True pampas grass (Cortaderia selloana) is not reliably hardy much below zone 7. And yes, if it survived the winter, it should be showing signs of new growth by now.

my pampas grass is the colour of corn i would like to know if you think it has survived the winter

Corn can be many colors; green, green with white or yellow stripes, yellow, red, tan, etc..

A photo would help.

What hardiness zone are you in, or...how low did your winter temperatures go?