Meat pies usually spoil as a result of the growth of molds. Their spores usually contaminate the product during cooling and storage prior to packaging. Spoilage by mesophilic bacilli and clostridia may occur if pies are stored under warm conditions. Traditional Shepherds pie may be cooked in bulk and will be subject to spoilage by clostridia or bacilli if not cooled rapidly after cooking.
NatanaclTM is effective against mold, while NisinZTM is effective against mesophilic bacilli and clostridia in meat filled pies.