Which of the following is NOT a method of measuring beef quality?

The correct choice, which indicates that age assessment is not a method of measuring beef quality, highlights an important aspect of beef evaluation. While age can provide some insights related to tenderness and flavor, it is not a direct measure of quality in the same manner as other methods listed.

Carcass weight is a clear indicator of the yield and economic return potential of the beef, as heavier carcasses generally translate to more meat. Marbling score assesses the intramuscular fat distribution, significantly influencing the tenderness, juiciness, and flavor, which are all crucial components of beef quality. Color analysis informs us about the freshness and wholesomeness of beef, with color being an important visual cue for consumers regarding the meat's appeal.

In contrast, while age assessment may indirectly affect some quality traits, it does not directly measure the beef's quality attributes like tenderness, flavor, or juiciness that are essential for the overall evaluation of beef. Thus, it stands apart as a less relevant metric when specifically discussing beef quality.