I know a little bit about this diet and can share with you what I know.
Proteins are accepted as the trigger for food hypersensitivity reactions. As such starch would be considered to be reaction free as long as it doesn’t have residual protein. In talking to RC about the quality control in their diets they reported to use DNA fingerprinting on the ingredients before being used and PCR testing as well to ensure unwanted proteins are not present. As an aside in a comprehensive review of allergens corn was the culprit in only 3% of food reactions. Other studies have found higher results but overall it hasn’t been documented as one of the top allergens.
Hypersensitivity reactions from protein chains are correlated to chain length. Shorter length chains are less likely to trigger a reaction and amino acids are reaction free. In this diet the “protein” is hydrolyzed… separated to the AA level. The AA source is from the feather shafts of chickens. RC told me they purchase this AA powder from a source I think in the Netherlands?? RC said this AA powder is the same one that is used in Neocate, a formula for infants with extreme health problems. AAFCO didn’t have a specific ingredient descriptor for this unique ingredient and hydrolyzed poultry by product aggregate in what was used.
While the AA source is from chicken the diets would theoretically be reaction free.
