Reduction of acrylamide content of ripe olives by selected additives

A model system based on alkali-treated olive juice heated at 121 °C for 30 min was used to screen different additives (salts, amino acids, antioxidants) for potential inhibition of acrylamide formation in ripe olives. The most-efficient inhibitors found were sodium bisulphite, l-cysteine, and l-arginine. These compounds, as well as other sulphur-containing compounds (N-acetyl-l-cysteine, reduced glutathione, methionine) and several natural products (tea, oregano, rosemary, garlic), were then added to black ripe olives prior to sterilisation to evaluate their effect on both the acrylamide content and the sensory quality of olives. Sodium bisulphite had the highest impact on the acrylamide level in black ripe olives without a negative repercussion on sensory quality. Arginine and blanched garlic showed promising results. SH-containing compounds such as l-cysteine, N-acetyl-l-cysteine, or reduced glutathione were as effective as sodium bisulphite in reducing acrylamide, but did generate unpleasant off-flavours.