Acrylamide in roasted almonds.
Acrylamide is a chemical that forms naturally in some carbohydrate-rich foods (e.g., potatoes, bakery products, cereals) during frying, roasting and baking. In foods, most acrylamide is formed through a reaction between the free amino acid asparagine and the reducing sugars glucose and fructose. This reaction occurs mainly during the heating of food above 250°F (~121°C) in low-moisture conditions and is part of the Maillard reaction (also known as non-enzymatic browning).
Acrylamide at concentrations found in some foods is a concern because the chemical is known to cause cancer in laboratory animals and also may be a human carcinogen.
Almonds contain free asparagine and reducing sugars, the precursors for acrylamide formation. Acrylamide is not found in raw almonds, but is found in roasted almonds. Many factors influence the acrylamide levels in roasted almonds; most importantly, the roasting conditions, but also almond composition, variety and maturity.
Since 2003, the Almond Board of California has funded numerous research projects investigating acrylamide levels in almonds. These projects have ranged from commercial product surveys, analyses of acrylamide precursors in various almond varieties, and studies on how roasting temperature and time, as well as storage after roasting, may influence acrylamide levels.
A study published in the Journal of Agricultural and Food Chemistry found that roasting at a temperature below 295°F (146°C) to achieve light- or medium-roasted product will minimize acrylamide formation in roasted almonds. The University of California researchers demonstrated that roast temperature has a much greater influence on the final acrylamide content than the process time.