During breaks, coffee, tee, water and cookies will be served. For lunch, a visit to the Mensa I (cafeteria) is recommended, which is located close to the Audimax (opening hours: Mo - Fr 11.15 - 14.00 h).
Mensa 1 am Westring, Westring 385, 24118 Kiel
Here you can eat at reasonable prices.
Additionally, the "Campussuite" is located on the campus, where you can get tasty snacks.
Of course, the city offers numerous restaurants as well.