Here's a list of basic (raw) items I've found so far that the new storehouses will hold.
Vanilla
Red Liquorice
Green Liquorice
Ginger
Caramel
Chocolate
Cinnamon Bark
Gelatin
Apples
Apricots
Bananas
Blackberries
Potatoes
Carrots
Blueberries
Red Grapes
White Grapes
Pumpkins
Pumpkin Seeds
Cedar Sap
Elm Sap
Oak Sap
Maple Sap
Yew Sap
Rice
Rye
Wheat
Barley
Clay all tiers
Fungus all tiers, caps and strips
Fish all tiers
Ruxus Flank
Chicken Breast
Arbotus Flank
Salt, ground and rock
Pepper (new)
Sugar, cane and refined
Eggs
Milk