diff --git a/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoalGenerator.java b/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoalGenerator.java
index 6fb7e05e9..c2c9e3d7b 100644
--- a/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoalGenerator.java
+++ b/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoalGenerator.java
@@ -79,7 +79,7 @@ public class TileEntityCoalGenerator extends TileEntityInventoryBase implements
                 this.maxBurnTime = burnTime;
                 this.currentBurnTime = burnTime;
 
-                this.slots[0] = StackUtil.addStackSize(this.slots[0], -1);
+                this.slots[0] = StackUtil.addStackSize(this.slots[0], -1, true);
             }
 
             if(flag != this.currentBurnTime > 0){
diff --git a/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoffeeMachine.java b/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoffeeMachine.java
index 32b0402d6..950600fd4 100644
--- a/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoffeeMachine.java
+++ b/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityCoffeeMachine.java
@@ -157,7 +157,7 @@ public class TileEntityCoffeeMachine extends TileEntityInventoryBase implements
                                 CoffeeIngredient ingredient = ItemCoffee.getIngredientFromStack(this.slots[i]);
                                 if(ingredient != null){
                                     if(ingredient.effect(output)){
-                                        this.slots[i] = StackUtil.addStackSize(this.slots[i], -1);
+                                        this.slots[i] = StackUtil.addStackSize(this.slots[i], -1, true);
                                     }
                                 }
                             }
diff --git a/src/main/java/de/ellpeck/actuallyadditions/mod/util/StackUtil.java b/src/main/java/de/ellpeck/actuallyadditions/mod/util/StackUtil.java
index ccfbfab57..9b5940b78 100644
--- a/src/main/java/de/ellpeck/actuallyadditions/mod/util/StackUtil.java
+++ b/src/main/java/de/ellpeck/actuallyadditions/mod/util/StackUtil.java
@@ -50,8 +50,12 @@ public final class StackUtil{
     }
 
     public static ItemStack setStackSize(ItemStack stack, int size){
+        return setStackSize(stack, size, false);
+    }
+
+    public static ItemStack setStackSize(ItemStack stack, int size, boolean containerOnEmpty){
         if(size <= 0){
-            if(isValid(stack)){
+            if(isValid(stack) && containerOnEmpty){
                 return stack.getItem().getContainerItem(stack);
             }
             else{
@@ -63,6 +67,11 @@ public final class StackUtil{
     }
 
     public static ItemStack addStackSize(ItemStack stack, int size){
-        return setStackSize(stack, getStackSize(stack)+size);
+        return addStackSize(stack, size, false);
     }
+
+    public static ItemStack addStackSize(ItemStack stack, int size, boolean containerOnEmpty){
+        return setStackSize(stack, getStackSize(stack)+size, containerOnEmpty);
+    }
+
 }