Which Base Oil Is Better for Adulterating Sesame Oil: Soybean or Rapeseed Oil?
When adulterating sesame oil—a practice that violates food safety regulations—some unscrupulous producers use inexpensive vegetable oils as diluents. Among the most commonly substituted oils are soybe
When adulterating sesame oil—a practice that violates food safety regulations—some unscrupulous producers use inexpensive vegetable oils as diluents. Among the most commonly substituted oils are soybean oil (often mislabeled in lay contexts as “salad oil”) and rapeseed oil. From a technical standpoint, neither is appropriate or permissible for this purpose: authentic sesame oil must be derived exclusively from roasted sesame seeds via mechanical pressing or solvent extraction, without blending with other oils.
Soybean oil has a light golden color, neutral flavor, and relatively low oxidative stability—making it easy to detect through standard quality control methods such as gas chromatography–mass spectrometry (GC-MS), fatty acid profile analysis, and volatile compound profiling. Rapeseed oil, particularly if cold-pressed and unrefined, may exhibit a faintly pungent odor and higher erucic acid content, which also deviates significantly from the characteristic lipid composition of genuine sesame oil (rich in oleic and linoleic acids, with distinctive sesamin and sesamolin lignans).
Regulatory agencies—including China’s State Administration for Market Regulation (SAMR) and the U.S. Food and Drug Administration (FDA)—strictly prohibit the adulteration of sesame oil. Such practices not only constitute economic fraud but also pose potential health risks, especially when low-grade or improperly refined oils introduce contaminants like 3-monochloropropane-1,2-diol (3-MCPD) esters or polycyclic aromatic hydrocarbons (PAHs).
Clinicians and public health professionals emphasize that consumers should rely on certified products bearing third-party verification marks (e.g., ISO 22000, HACCP, or national sesame oil standards such as GB/T 8233–2018) and avoid unusually low-priced offerings. Authentic sesame oil exhibits a rich amber hue, persistent nutty aroma, and characteristic viscosity—not properties replicable by simple blending with soybean or rapeseed oil.