Theses and Dissertations

Issuing Body

Mississippi State University


Silva, L. Juan

Committee Member

Tidwell, Diane

Committee Member

Matta, Frank

Date of Degree


Original embargo terms

MSU Only Indefinitely

Document Type

Graduate Thesis - Campus Access Only


Food Science and Technology

Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Food Science, Nutrition and Health Promotion


Microbial recovery methods for frozen blueberries, and postharvest sanitation treatments on microbial load and sensory attributes of berries were studied. Previously frozen rabbiteye blueberries were subjected to hand-mixing, machine-mixing, stomaching, vortexing, and homogenization. Aerobic (APC) and yeast and mold (YMC) counts did not differ amongst treatments but homogenization, stomaching, and vortexing tended to yield a higher recovery, with vortexing resulting in the choice method for YMC possibly due to cell disruption and colony breakage. Fresh highbush blueberries were treated with hot water (60 - 90°C) with an oxidizing agent (0 - 0.1% Boxyl®) for 10 – 30s. Water temperature was the most influential (p<0.05) factor on microbial reduction, wax/bloom and color. Holding berries at 75°C for 20s (without antimicrobial) or dipping in 200ppm chlorine for 10s resulted in 0.90 and 1.80 log reduction of APC and yeast, respectively; and 0.80 (200ppm/10s) and 2.90 (75°C/20s hot water) log reduction in mold counts.