The present invention relates to delayed release oral formulations comprising active ingredients and modified proteins used as excipients. The proteins have chemical modifications such as succinylation, deammation, glutarylation or phosphorylation which decrease the isoelectric point of the protein compared to the protein's native isoelectric point and enhance protein-protein interactions, thereby reducing solubility and swelling, and delaying release of the active ingredient when the formulation is ingested orally. Particularly, the invention relates to tablets that comprise an excipient of chemically-modified food proteins such as soy proteins or -lactoglobulin useful for delaying release of an active ingredient such as a pharmaceutical drug or a probiotic.