Quality evaluation should focus on purity, volatile oil content, and physical appearance. High-quality celery seeds (Apium graveolens) should have a purity level of at least 98-99%, with minimal stalks or dust. The volatile oil content, which determines the strength of the aroma and flavor, should ideally range between 1.5% to 3.0%. Visually, the seeds should be brown to dark brown, uniform in size, and free from mold or insect infestation. For industrial extraction, the moisture content must be kept below 10% to prevent microbial growth during transit.