Original research articleEffect of fat and salt reduction on the changes in the concentrations of free amino acids and free fatty acids in Cheddar-style cheeses during maturation

- The increase in FAA and FFA during maturation depended on level of fat and/or salt.
- Reducing fat significantly increased the mean concentration of FAA at times ≥90 d.
- FAA decreased on reducing salt content in the full-fat cheese.
- FFA decreased on reducing fat content but were unaffected by salt reduction.

The study investigated the effects of reducing fat content from 33 (full-fat, FF) to 22 (reduced-fat, RF) or 16 (half-fat, HF) % on the concentrations of total and individual free amino acids (FAA) and free fatty acids (FFA) in Cheddar-style cheeses with 1.9 (full-salt, FS), 1.2 (reduced-salt, RS) or 0.9 (half-salt, HS) % NaCl over a 270 d maturation period at 8 °C. Both FAA and FFA increased continuously during ripening, from ∼1200 and 230 mg/kg at 30 d to 5500 and 1593 mg/kg, respectively, in FFFS at 270 d. Reducing fat content resulted in higher concentrations of FAA (e.g., from 5500 mg/kg in FFFS to 6400 mg/kg in HFFS at 270 d) and lower levels of FFA (e.g., from 1593 mg/kg in FFFS to 1140 mg/kg in the HFFS cheese at 270 d). Reducing salt content from 1.9 to 1.2 or 0.9 % resulted in a significant decrease in FAA in the FF cheese, from 5500 mg/kg in FFFS to 4000 mg/kg in FFHS at 270 d. Salt content did not significantly affect the concentration of FAA in RF or HF cheeses, or the concentration of total or individual FFA in the FF, RF or HF cheeses.