The extraction of oil from tobacco (Nicotiana tabacum L.) seeds

Abstract

The classical extraction (maceration) of oil from the seeds of a tobacco (Nicotiana tabacum L.) plant strain, type Otlja, was carried out using n-hexane and petroleum ether as extracting solvents at different temperatures (25 ?C, 40 ?C and the boiling temperature) and seeds-to-solvent ratios (1:3, 1:5 and 1:10 w/v). The effects of the process factors on the kinetic parameters and the oil yield were assessed using the full factorial experiments 24. The oil yield was increased if the seeds were grounded before the extraction and by increasing the extraction temperature and by decreasing the seeds-to-solvent ratio. n-Hexane was somewhat more efficient than petroleum ether in the tobacco seed oil (TSO) extraction. The oil yield of 23.5 g/100 g of seeds (based on dry weight) was achieved using n-hexane at the seeds-to-solvent ratio of 1:10 w/v and the boiling temperature for the time of 60 minutes. The maceration was found to be less efficient in recovering the TSO than the Soxhlet extraction where the maximum oil yield of 31.1 g/100 of dry seeds was obtained. The kinetics of the oil extraction was described using the model of unsteady diffusion through plant material. The major fatty acid (FA) of oil recovered from the TSO was linoleic acid. The high acid value (37 mg KOH/g) indicated that the content of the free FA in the oil was quite high.