The main aim of the present study was to predict the growth of the food spoilage yeast Debaryomyces hansenii by multivariate data analysis (MVDA) using temperature, pH and NaCl concentration as growth parameters. Growth of five strains of D. hansenii (DHI, DHII, DHIII, DHIV and DHV) was measured as optical density at 620 nm (OD620) at different values of temperature, pH and NaCl concentrations. It was found that salt was the most important factor, which affects yeast growth followed by temperature. The growth of all yeast strains was reduced by increasing salt concentration and decreasing temperature. On the other hand, pH was found to have a little effect on the growth of D. hansenii. Strain DHII was the most salt-tolerant strains among the five yeast strains investigated. Partial least squares (PLS) prediction model was created out using pH, temperature and NaCl concentration to predict the growth of D. hansenii. The model was acceptable with a correlation of 0.86. The developed PLS model will help in optimizing the food process conditions that will prevent food spoilage by D. hansenii.

The main purpose of the present study was to isolate, identify and quantify bacteria in Palestinian fresh lamb meat. Phenotyping and 16S rRNA gene sequence analysis was used to identify bacteria present in lamb meat samples. Thirty-four bacterial isolates were obtained from 20 samples of fresh lamb meat collected from 4 meat shops in Tulkarem city in Palestine. Bacterial counts were in a range of 3 x 103 - 1.5 x 105 cfu / g with Staphylococcus aureus being the highest in numbers among other bacteria. Enterobacteriaceae and Staphylococcaceae were the predominant bacterial families detected in fresh lamb meat samples. Two bacterial isolates, which were not identified by phenotyping, were identified by 16S rRNA gene sequence analysis. There was an agreement between phenotyping and 16S rRNA gene sequencing in identification of 19 bacterial isolates. On the other hand, a disagreement was observed between phenotyping and 16S rRNA gene sequencing in identification of the remaining bacterial isolates. Fresh lamb meat seems to be a good medium for growth of various bacterial species