Theses and Dissertations


Wei-Chun Chen

Issuing Body

Mississippi State University


Silva, L. Juan

Committee Member

Matta, B. Frank

Committee Member

Schilling, W. Mark

Date of Degree


Document Type

Graduate Thesis - Open Access


Food Science, Nutrition and Health Promotion

Degree Name

Master of Science


College of Agriculture and Life Sciences


Department of Food Science, Nutrition and Health Promotion


The purpose of this study was to determine the quality and microbial load of blueberries at different maturity stages, to develop the effective microbial recovery method and to compare sanitation postharvest treatments on microbial counts of blueberries. The soluble solids and the sugar to acid ratio increased, while pH and TA decreased with maturity. Ripe berries had lower yeast and mold counts (YMC) at other maturity stages, but there were no differences on aerobic plate counts (APC). The medium pH was lower for stomaching and blending than hand massaged samples. This leads to higher recovery of microorganisms by massaging. Sodium hypochlorite at 400 ppm was effective in reducing APC but not YMC. Acidified sodium chloride was very effective, lowering APC and YMC below detectable level. All sanitation treatment did not influence sensory attributes of blueberries.