Cold-pressed rapeseed oil (CPRO) is a rich source of bioactive components, but it is more susceptible to deterioration due to absence of chemical refining. Proper storage conditions are essential to maintain oil quality. This study evaluated the quality properties of seed-stored oil (SSO) and oil-stored oil (OSO) under various storage conditions. Both the seeds and the CPRO obtained from the ‘Jungmo7001’ and ‘Yuryeo’ varieties were stored for 24 months at 4℃, 25℃, and ambient temperature (AT). After 24 months, the acid value (AV) at 4℃ was lower than at 25℃ and AT. Additionally, the AV increased by 3.0-fold in SSO and 1.9-fold in OSO at AT compared to initial storage levels. OSO was found to be relatively more stable against oxidation than SSO. The canolol content in SSO increased with both storage temperature and period, but this was not observed in OSO. However, no changes in fatty acid composition or tocopherol content were noted based on the storage conditions, indicating that these properties remained relatively stable during storage. These results provide foundational data for the stable distribution of CPRO.
In this study, quality properties of rapeseed oil by different roasting temperatures (140, 160, 180, and 200℃) were investigated. Roasted-pressed oil (RPO) showed a decrease in lightness and an increase in redness and yellowness with an increase in temperature compared to cold-pressed oil (CPO). In addition, the β-carotene and tocopherol content also increased in RPO as the roasting temperature increased. The tocopherol content increased by 18~20% in RPO at 200℃ compared to CPO. This increase in bioactive components led to improved radical scavenging activity dependent on roasting temperature, and RPO at 200°C showed a 2.7-fold improvement compared to CPO. Finally, it was observed that higher roasting temperatures resulted in an extended oxidation induction period, increasing by up to 3.3 times. In conclusion, roasting is an effective method for enhancing the oil functionality of domestic rapeseed varieties. This study provides basic data for producing high-quality oil.