A method of forming an edible meat substitute product includes obtaining a liquid waste stream from a pea protein processor. The method includes adjusting the pH of the liquid waste stream to be in a range of 5.5 to 6.0 so as to form a growth media. The method includes growing fungal cells in the growth media comprising the liquid waste stream obtained from a pea processor such that the fungal cells produce a mycelium mass. The method includes separating the mycelium mass from the growth media. The method includes concentrating the mycelium to obtain a fibrous mycelium mass having a protein content of greater than 40 wt % of a dry mass of the mycelium.