This is an unflown package of white bread. The bread is made in small cubes and sealed inside a plastic envelope. A cosmonaut can break off small bite-sized pieces without shedding crumbs inside the spacecraft.
The Director of the Memorial Museum of Cosmonautics donated this item to the museum while visiting Washington, D.C.
This object is on display in Human Spaceflight at the Steven F. Udvar-Hazy Center in Chantilly, VA.