Where can I find Acid preserves in Greppen?

Acid preserves can also be found in these cities:

Altdorf Baar Buchrain Buochs Cham Ebikon Emmen Goldau Hitzkirch Horw Ibach SZ Ingenbohl Kriens Küssnacht Lucerne Malters Rain Rotkreuz ZG Sarnen Sempach Stans Steinhausen Unterägeri Urswil Wädenswil Zug

You can also find this in Greppen:

Desserts Dessert Baking Mixes Cake Glaze Peanut Butter Ice Cream Rice Dishes Vegetable Juices Instant Iced Coffee Cheese Roll Canned Fish