The Influence of pH and Sodium Hydroxide Exposure Time on Glucosamine and Acrylamide Levels in California‐Style Black Ripe Olives

Acrylic acid, N ‐acetyl‐glucosamine and glucosamine were investigated for their role in the formation of acrylamide in California‐style black ripe olives [CBROs]. Levels of acrylic acid and glucosamine are reported for the first time in fresh (333.50 ± 21.88 and 243.59 ± 10.06 nmol/g, respectively) and in brine‐stored olives (184.50 ± 6.02 and 165.88 ± 11.51 nmol/g, respectively). Acrylamide levels significantly increased when acrylic acid (35.2%), N ‐acetyl‐glucosamine (29.9%), and glucosamine (124.0%) were added to olives prior to sterilization. However, isotope studies indicate these compounds do not contribute carbon and/or nitrogen atoms to acrylamide. The base‐catalyzed degradation of glucosamine is demonstrated in olive pulp and a strong correlation ( r 2 = 0.9513) between glucosamine in olives before sterilization and acrylamide formed in processed CBROs is observed. Treatment with sodium hydroxide (pH > 12) significantly reduces acrylamide levels over 1 to 5 d without impacting olive fruit texture.