Comparative Study of the Solvent Extraction and Characterization of Oil from the Seeds of Avocado, Bush Pear and Cashew

Abstract

Due to their many purposes and functions for mankind, oils from fruits and seeds are given a lot of importance today. As a result, there is a higher demand for cashew, avocado, and bush pear oils. The Soxhlet extractor and petroleum ether as the extracting solvent are used in this work to extract and characterize the oils from the seeds of Cashew, Avocado, and Bush pear. Physical and chemical studies of the extracted oil were performed alongside with the identification of any trace metals. The findings assessed the yield, color, relative density, refractive index, acid value, peroxide value, iodine value, and saponification value free fatty acid for Bush pear, Avocado pear, and Cashew seeds. The yield (%) of the oil produced from the various seeds of cashew, avocado, and bush pear oils is of specific significance. This finding reveals highest oil yield of 38.2% in Avocado pear oil, compared to 34.4% and 27.4% oil yield in Bush pear seed, and Cashew seed, respectively. In addition to being edible, Bush pear and Cashew oil's low acid value of 6.4 mg KOH/g and 7.7 mg KOH/g, respectively compared to Avocado oil's low acid value of 14.6 mg KOH/g avocado suggests that Bush pear and Cashew oils finds good applications in the paint industry. The study also showed that potassium had the highest concentration of any metal, with 45.8 mg/100g in avocado oil, compared 24.9 mg/100g and 1.68 mg/100g for Cashew seed oil and Bush pear, respectively. Zinc had the lowest concentration, with a value of 0.38 mg/100g observed in Cashew compared with 1.32 mg/100g and 2.06 mg/100g for Bush pear and Avocado, respectively. Hence, this reveals that Oils extracted from Cashew finds good applications in the production of hydraulic oil with exceptional lubrication properties. The FTIR study shows that functional groups including alkanes, alkenes, carbonyls, etc. are present in the seed oils of Bush pear, Avocado pear, and Cashew seeds.