Quality Properties, Fatty Acid Composition, and Mineral Contents of Some Citrus Seeds and Oils Extracted by Solvent Extraction

In this study, while the oil yields of Citrus seeds were found to be between 27.61% (mandarin) and 36.42% (bitter orange), the crude protein contents of seeds ranged between 10.54% (bitter orange) and 14.21% (lemon). Total phenolic and total flavonoid amounts of Citrus seeds were determined to range from 411.43 mg GAE/100 g (lemon) and 814.84 mg GAE/100 g (bitter orange) to 97.84 mg/100 g (grapefruit) and 126.48 mg/100 g (lemon). In addition, the antioxidant activity values of Citrus seeds ranged between 53.27% (mandarin) and 74.21% (lemon). Results showed some differences depending on fruit type. In general, the sugar content of bitter orange was found to be low. However, the most abundant sugar in all samples was sucrose. Oleic and linoleic acid amounts of Citrus seed oils were detected to range from 21.84% (bitter orange) and 27.58% (grapefruit) to 33.94% (lemon) and 38.67% (mandarin). According to the results, the minerals found in the greatest amounts in the seeds were phosphorus, magnesium, potassium, and calcium, followed by sodium, iron, zinc, manganese, and copper.

Automated summary

This study found variations in oil yields and protein contents of Citrus seeds among different varieties. Citrus seeds contain abundant phenolic and flavonoid compounds with antioxidant activity. The seeds also contain high levels of oleic and linoleic acids, as well as various minerals.