New Delhi, Feb. 19 -- A family member of H.B. Reese has accused chocolate maker The Hershey Company of quietly changing the recipe of some of the products sold under Reese's Peanut Butter Cups brand.

"My grandfather built Reese's on a simple, enduring architecture: milk chocolate + peanut butter," Brad Reese, the grandson of H.B. Reese, wrote in a letter to The Hershey Company.

"But today, Reese's identity is being rewritten, not by storytellers, but by formulation decisions that replace milk chocolate with compound coatings and peanut butter with peanut‑butter‑style cremes across multiple Reese's products," the letter, which was also posted on LinkedIn by Reese, stated.

"How does The Hershey Co. continue to position Reese'...