Where can I find Baking soda in Koppigen?

Baking soda can also be found in these cities:

Bern Biberist Bremgarten bei Bern Burgdorf Derendingen Gerlafingen Grenchen Hasle bei Burgdorf Herzogenbuchsee Hinterkappelen Huttwil Ittigen Kirchberg Langendorf Langenthal Moutier Murgenthal Münchenbuchsee Oensingen Ostermundigen Solothurn Utzenstorf Zollikofen Zuchwil

You can also find this in Koppigen:

Baked Goods Yeast Fresh Pumpernickel Breakfast Cereals Olives Drinks Dry Herbs Spaetzle Snacks Horseradish