Phytochemicals in recovered seed oils from by-products of common quince (Cydonia oblonga) and Japanese quince (Chaenomeles japonica)

Nearly 100% of Japanese quince (Chaenomeles japonica) and common quince (Cydonia oblonga) fruits are processed. It generates large amounts of seeds. One of the possible utilization of seeds is oil recovery. Seeds of both quinces were tested for their oil recovery using two methods—solvent-free protocol by mechanical press and ultrasound-assisted extraction (UAE) applying n-hexane, and phytochemistry of obtained oils was studied. The oil yield was nearly twice higher from common quince than Japanese quince (20.9% and 11.2%, respectively) for UAE. Compared to UAE, screw-pressed allowed for 67% oil recovery. In general, the phytochemical profile of both quince seed oils was similar with some differences in the content of individual compounds. The two quince seed oils were dominated by the same molecules in different compound groups: fatty acids—linoleic acid; tocochromanols—α-tocopherol; phytosterols—β-sitosterol, and triterpenoid—squalene. Common quince seed oil was richer in tocochromanols, squalene, and linoleic acid, whereas Japanese quince seed oil was richer in phytosterols. The present study showed the oil potential of fruit industry by-products and the relatively high oil recovery by the environmentally friendly/healthy technique of extraction (solvent-free) to achieve ultimately high-quality products in a “Natural-Safe-Green” strategy.

Practical applications: Production of fruit each year, especially those used for processing, for example, common quince (C. oblonga), has been increasing in recent years, likely, so has processing and amounts of generated by-products, including seeds. To reduce the costs, CO₂ emissions, and other environmental safety aspects of production, different techniques of plant oil recovery are considered. The extraction method affects oil yield as well as its phytochemical composition. The generated information in the present study can contribute to improved effectiveness of the use of plant material thereby providing environmental, health, and economic benefits.