Removes parasites from raw_milk

data/json/items/comestibles/dairy.json

@@ -7,6 +7,7 @@
     "copy-from": "milk",
     "spoils_in": "12 hours",
     "price": 19,
+    "contamination": 30,
     "description": "This is raw, unhomogenized and unpasteurized milk from a cow.  It couldn't be any fresher unless you drank it straight from the cow, which might upset it.  Depending on your dietary sensibilities, you might want to pasteurize or even boil this before drinking."
   },
   {

src/consumption.cpp

@@ -949,6 +949,14 @@ bool player::eat( item &food, bool force )
         }
     }
 
+    // chance to get foodpoisoning from bacterial contamination
+    if( !will_vomit && !has_bionic( bio_digestion ) ) {
+        const int contamination = food.get_comestible()->contamination;
+        if( rng( 1, 100 ) <= contamination ) {
+            add_effect( effect_foodpoison, rng( 6_minutes, ( nutr + 1 ) * 6_minutes ) );
+        }
+    }
+
     if( will_vomit ) {
         vomit();
     }

src/item_factory.cpp

@@ -1678,6 +1678,7 @@ void Item_factory::load( islot_comestible &slot, JsonObject &jo, const std::stri
     assign( jo, "stim", slot.stim, strict );
     assign( jo, "healthy", slot.healthy, strict );
     assign( jo, "parasites", slot.parasites, strict, 0 );
+    assign( jo, "contamination", slot.contamination, strict, 0, 100 );
     assign( jo, "freezing_point", slot.freeze_point, strict );
     assign( jo, "spoils_in", slot.spoils, strict, 1_hours );
     assign( jo, "cooks_like", slot.cooks_like, strict );

src/itype.h

@@ -149,6 +149,9 @@ struct islot_comestible {
     /** chance (odds) of becoming parasitised when eating (zero if never occurs) */
     int parasites = 0;
 
+    /** probability [0, 100] to get food poisoning from this comestible */
+    int contamination = 0;
+
     /** freezing point in degrees Fahrenheit, below this temperature item can freeze */
     int freeze_point = temperatures::freezing;