We describe a food additive comprising a PS4 variant polypeptide, in which
the PS4 variant polypeptide is derivable from a parent polypeptide having
non-maltogenic exoamylase activity, in which the PS4 variant polypeptide
comprises an amino acid substitution at position 121 with reference to
the position numbering of a Pseudomonas saccharophilia exoamylase
sequence shown as SEQ ID NO: 1. The PS4 variant polypeptide may further
comprise one or more further mutations at a position selected from the
group consisting of: 161 and 223, preferably 161A, 223E and 223K, more
preferably S161A, G223E and/or G223K, or the group consisting of: 134,
141, 157, 223, 307, 334, 33 and 34, preferably G134R, A141P, I157L,
G223A, H307L, S334P, N33Y and D34N. In preferred embodiments, the PS4
variant polypeptide further comprises a mutation at position 87,
preferably G87S, a mutation at position 178, preferably L178F, and/or a
mutation at position 179, preferably A179T.