Is it normal this white substance in my canned green peas?
Looks like starch. Several sites I find mention this for different vegetables containing starch, and they all seem to quote Causes and Possible Solutions for Problems with Canned Foods from the National Center for Home Food Preservation (note that these are guidelines for canning):


  Problem:
      Cloudy liquid (sometimes denotes spoilage)
  
  Causes and solution:
      1. Starch in vegetables   - Select products at desirable stage of maturity. Do not use overmature vegetables. If canning potatoes, use fresh boiling water to cover and not cooking liquid from preparing hot pack.
      2. Minerals in water      - Use soft water.
      3. Additives in salts     - Use pure refined salt (pickling or canning salt) without additives.
      4. Spoilage               - Prepare food as directed with published canning process. Process by recommended method and for recommended time.


I would just drain and rinse them, and let my taste and smell be the ultimate guide.

Another guideline formulated a little differently