Which raw-milk quality indicators are most important for pre-pasteurization assessment?

• A. pH, temperature, and viscosity.
• B. Sometimes nothing matters; pre-pasteurization quality is not assessed.
• C. SPC, Coliform count, and Somatic Cell Count.
• D. Fat content and overall color only.

Answer: (C)

The main idea here is that pre-pasteurization quality is evaluated using microbial and udder-health indicators, because these reflect the actual safety and quality threats that pasteurization will have to deal with. The three most important indicators are Standard Plate Count, Coliform count, and Somatic Cell Count.

Standard Plate Count measures the total number of viable bacteria in the milk. It acts as a broad hygiene barometer for the farm, milking process, and handling. A high SPC means the milk carries a larger bacterial load, which can lead to faster spoilage and higher chances that heat treatment won’t be as effective at achieving quality targets after pasteurization.

Coliform count serves as a hygiene indicator for fecal contamination and overall sanitation of milking practices and equipment. Low coliform levels suggest clean processes and reduce the risk of pathogenic contamination, making pasteurization more reliably effective in ensuring safety.

Somatic Cell Count is a measure of udder health; higher SCC indicates mastitis and compromised milk quality. Milk from cows with high SCC can have altered composition and increased microbial risk, which can affect flavor, texture, and shelf life, and it signals potential quality issues that need addressing before processing.

Other options focus on properties like pH, temperature, viscosity, fat content, or color, which relate more to process control or appearance than to the microbial quality and safety status assessed before pasteurization.

So, focusing on SPC, Coliform count, and SCC provides the most direct picture of raw-milk quality relevant to safe and effective pasteurization.