Venezuelan White Cheese: Composition and Quality ¹

Area of Science:

• Food Science and Technology
• Microbiology
• Public Health

Background:

• Queso blanco is a staple cheese in Venezuela, crucial to the local diet.
• Understanding its compositional and microbial profile is essential for food safety and quality assessment.
• Previous characterizations of Venezuelan queso blanco are limited, particularly regarding retail-level products.

Purpose of the Study:

• To analyze the basic compositional characteristics of Venezuelan queso blanco.
• To assess the microbial profile, including indicator organisms and potential pathogens.
• To investigate variations between 'soft' (pasteurizado blando) and 'hard' (duro) commercial types.

Main Methods:

• Retail-level survey of Venezuelan queso blanco.
• Determination of moisture, sodium chloride, fat, and protein content.
• Microbiological analysis for total fecal coliforms, Escherichia coli, Salmonella, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Lactobacillus, yeasts, and molds.

Main Results:

• Significant variations in moisture, salt, fat, and protein content were observed between soft and hard queso blanco.
• Soft queso blanco: 50.6% moisture, 2.5% NaCl, 21.4% fat, 19.2% protein, pH 5.7.
• Hard queso blanco: 39% moisture, 5.0% NaCl, 27.4% fat, 24.5% protein, pH 5.3.
• High levels of fecal coliforms, E. coli, and Staphylococcus aureus (including enterotoxigenic strains) were detected.
• Pathogens such as Salmonella were identified.
• Other microorganisms including Bacillus cereus, Clostridium perfringens, Lactobacillus, yeasts, and molds were present.

Conclusions:

• Considerable variability in queso blanco composition suggests inconsistent manufacturing processes and potential quality control issues.
• The prevalence of indicator organisms and pathogens poses significant food safety risks to consumers.
• Further investigation into the relationship between microbial load, specific pathogens, and compositional factors is warranted.