Change the connection strings in MVC3 to publish in IIS

Change the connection strings in MVC3 to publish in IIS

I need to change the connection strings un my mvc proyect because is local
and now I need publish in a server but I dont have idea how write the
connection strings and they are the next
<add name="cnn" connectionString="Data
Source=SISTEMAS-PC\SQLEXPRESS;Initial Catalog=FoodGroups;User
ID=FoodGroup; Password=Food" providerName="System.Data.SqlClient" />
<add name="DefaultConnection" providerName="System.Data.SqlClient"
connectionString="Data Source=(SISTEMAS-PC\SQLEXPRES)\v11.0;Initial
Catalog=aspnet-MvcApplication1-20130730182253;Integrated
Security=SSPI;AttachDBFilename=C:\Users\Sistemas\Desktop\proyectos
TI\foodGroup2\foodGroup\App_Data" />
<add name="FoodGroupsEntities"
connectionString="metadata=res://*/Model1.csdl|res://*/Model1.ssdl|res://*/Model1.msl;provider=System.Data.SqlClient;provider
connection string=&quot;data source=SISTEMAS-PC\SQLEXPRESS;initial
catalog=FoodGroups;user
id=FoodGroup;password=Food;MultipleActiveResultSets=True;App=EntityFramework&quot;"
providerName="System.Data.EntityClient" />