P2-12 Effect of Oil Roasting on Salmonella enterica Serovar Enteritidis PT30 on Coated Almonds

Tuesday, August 2, 2016
America's Center - St. Louis
Shirin Abd, Covance Laboratories, Inc., Livermore, CA
Antoinette de Senna, The National Food Lab, Livermore, CA
Anne Nillo, The National Food Lab, Livermore, CA
Carrie Ferstl, Covance Laboratories, Inc., Livermore, CA
Introduction: Almond Board of California (ABC) previously evaluated the efficacy of hot oil to reduce Salmonella Enteritidis PT30 on oil-roasted almonds and determined that a minimum process of 2.0 minutes at 260°F or above is required to provide a 5-log reduction of Salmonella on whole kernel almonds. ABC would like to determine if the oil roasting process recommended for whole kernel almonds is suitable for various sugar coated almonds which are also produced under similar process conditions.

Purpose: To evaluate the impact of different almond coatings (Honey, Xanthan, Starch) on the effectiveness of oil roasting at 260°F for various holding times to kill Salmonella on almonds.

Methods: Whole kernel almonds were artificially-inoculated with Salmonella, coated with a Honey, Xanthan, or Starch-based coating, and then oil-roasted at 260°F for 0.0, 1.0, 1.5, 2.0 minutes. Inoculated uncoated almonds were also included in the study for comparison. Log reductions following heat treatment for each treatment time between each almond product were compared using ANOVA.

Results: Log reductions of Salmonella following heat treatment at 260°F for 1 or 1.5 minutes were inconsistent, and ranged between 3.08±0.93 and 4.89±1.73 logs (n=9), or 4.87±0.38 and 6.28±0.90 logs (n=9), respectively, with standard deviations ranging from 0.35-1.73 log CFU/g for each of the different almond products. A greater than 5-log reduction of Salmonella was achieved after oil roasting at 260°F for 2.0 min, with the least amount of reduction observed on the uncoated almonds. No significant differences (P>0.05) were observed between the log reduction of Salmonella achieved for each type of sugar-coated almond after exposure to hot oil for 1.5 or 2.0 minutes.

Significance: The commercial oil roasting process at a higher temperature of 260°F for longer than 2.0 minutes should be sufficient to achieve a greater than 5-log reduction of Salmonella on Uncoated, Honey Coated, Xanthan Coated, and Starch Coated almonds.