Dog food allergies account for roughly 20 percent of all dog allergies.  The most common symptom of a food related allergy in dogs is itchy skin particularly on feet, legs, armpits, ears, face and anus.  Baldness from biting and scratching, hot spots and skin diseases can be consequences of an untreated food allergy.  There are many ingredients that may cause food related allergies in dogs.  These are though not prohibited to; meat, chicken, eggs, wheat, corn, fish and soy.  

Before treating a food allergy you should cure any secondary contagions or conditions that are occurring like skin infections, mange, yeast-related infections, and so on.  Once all these are cured then a food trial can start.  

Most allergies are linked with a selected protein of carbohydrate that is in the food or treats the dog is eating.  A food trial or elimination diet consists of feeding the dog a food containing a protein source and carbohydrates that the dog has never had before.  The trial is composed of 12 weeks of only this food.  This implies no treats, rawhide or any other type of dog gnaw (pig ears, bully sticks, and so on.), flavored medicines, toys or toothpaste of any kind.  

If the food for the elimination diet has a version in a can you can use bits of this as treats.  The dog must not ramble giving them access to eating things in the yard that can cause these symptoms.  I believe that you get the point; you don’t have to quarantine the dog but make sure the diet is all they’re eating or playing with.  At the end of the trial the dog is reintroduced to the food they were given to begin with to confirm the allergen is in the food.  

The remedy for these allergies is avoidance of the things that worsened them in the 1st place.  Short term relief for the symptoms can be achieved thru the use of antihistamines and steroids but the sole cure is thru avoidance of the offensive ingredients.  At this time your veterinarian may prescribe a particular sort of food to put your dog on or you can investigate a homemade diet.  If you opt to use a homemade diet it can afford you the ability to control exactly everything that goes into the food.  
Commercial dog foods aren’t bound by law to list each ingredient on the pet food label.  If you go the homemade route makes sure your formula contains all of the nutrient elements your dog wants.

Go to Dog Food Allergies for more info which will help you to understand more about Homemade Dog Food For Dogs With Allergies