Food Science and Technology Project Topics

Production and Characterization of Pawpaw Seed Oil and Groundnut Oil

Production and Characterization of Pawpaw Seed Oil and Groundnut Oil

Production and Characterization of Pawpaw Seed Oil and Groundnut Oil

Chapter One

The Objective of the Study

The aim and objective of this work is the extraction of oil from papaya seed and groundnut and determine the physicochemical properties and the quality of oil extracted from papaya seeds and groundnut.


 REVIEWS ON PAWPAW (Carica papaya)

 Brief Introduction to Carica papaya and its Seed

Papaya belongs to a small family caricaceae having four genera in world. The genus carica L. is represented by four species in India, of which Carica papaya L. is the most widely cultivated and the best-known species (Jean et al., 2011). It is commonly known as Papaya Melon tree, Pawpaw or Papau, Kapaya, Lapaya, Papyas, Papye, Tapayas, Fan mu gua, papita, arand- kharpuja, papayabaum and papaya. The taxonomical classification includes Kingdom (Plantae), Order (Brassicales), Family (Caricaceae), Genus (Carica) and Species (papaya). Papaya is probably originated in southern Mexico and Costa Rica, subsequently got introduced in Australia, Hawaii, Philippines, Sri Lanka, South Africa, India and all tropical and subtropical regions. It is growing both commercially and in home garden (Marotta et al., 2006). A study conducted by University of Florida researchers Nam Dang and colleagues in Japan has documented papaya’s powerful anticancer properties and its impact on numerous lab-grown-tumors.

The papaya seed contain fatty acids, crude protein, crude fibre, papaya oil, carpaine, caricin, glucotropaeolin, benzyl glucosinolates, benzyl Isothiocyanate, benzyl thiourea, hentriacontane, ß-sitostrol, caressing and an enzyme myrosin. The seeds and the pulp of Carica papaya contain benzyl glucosinolate which can be hydrolyzed by myrosinase to produce benzyl isothiocyanate. Seed extracts have profound bactericidal activity. The seeds of unripe fruits are rich in benzyl isothiocyanate, a sulphur containing chemical that has been reported to be an effective germicide and insecticide. These substances are important for plant natural defense mechanisms (El Moussaoui et al., 2001). Medicinal uses of papaya seed are carminative, anti-fertility agent in males, counter irritant, as a paste in the treatment of ringworm, psoriasis, emmenagogue, vermifuge, liver cirrhosis and abortifacient. Seed juice is used for bleeding piles, enlarged liver and pectoral properties. Seed paste is used as anthelmintic, stimulation of menstruation or abortion.

Carica papaya seeds were approved and confirmed in some studies for their effective anthelmintic properties against nematodes found in animals (Chota, 2010). Chinoy et al., (2006) proved the anti-fertility, anti-implantation and abortifacient properties of extracts from papaya seeds. It has been established in males that the seeds of C. papaya are potential anti-fertility drugs (Lohiya et al., 2005). Pawpaw seeds are used to produce an indigenous Nigerian food condiment called ‘daddawa’, the Hausa word for a fermented food condiment (Dakare, 2004). Fermented seeds have no effects on litters of rats (Abdulazeez et al., 2009), whereas, those effects were apparent when the unfermented extract was administered (Abdulazeez, 2008). Anthelmintic activity of papaya seed has been predominantly attributed to carpaine (an alkaloid) and carpasemine (later identified as benzyl thiourea). Carpaine has an intensively bitter taste and a strong depressant action on health.

  Composition of Carica papaya

Researchers have found that differences in cultivars, growing location, sunlight exposure, agricultural practices, stage of ripeness and postharvest handling have significant effects on the chemical composition of the fruits (De-Rosso and Mercadante, 2005; Wall, 2006; Ornelas-Paz et al., 2008; Gayosso-García et al., 2011). For instance, the progression of fruit through different maturity stages results in physiological and biochemical changes that modify fruit composition and enables its consumption (Pereira et al., 2009). The loss of fruit firmness is a consequence of changes in plant cell wall constituents that lead to weak cell-to-cell links and thus lose of rigidity and firmness. The softening indicates ripening. These changes can be observed in papaya fruit tissue by means of microscopic examination (Pereira et al., 2009). For commercial production papaya fruit maturity is often based on the changes of skin colour of the fruits.

Papaya fruits have a good nutritional health profile being an excellent source of provitamin A and ascorbic acid. They rank as one of the top fruit for ascorbic acid content. There is no significant variation of the ascorbic acid content of different cultivars of the fruits but there is a large variation in the provitamin A content between the red and yellow-fleshed papaya cultivars (Chandrika et al., 2003; Wall, 2006) as well as a variation due to the level of ripeness of the fruit (Gayosso-García et al., 2011). The ripening process begins when the chlorophyll is degraded, which coincides with carotenoid synthesis and results in significant colour changes from green to yellow-orange colour. Moreover, during ripening, the content of esterified carotenoids increases, which allows esterified carotenoids to integrate more quickly into the membranes. This in turn increases the color of the fruit and its accumulation in chromoplasts (Andersson et al., 2008; Yahia and Ornelas-Paz, 2010).





Whole papaya fruits and matured groundnut were procured from local market of Owo. Most of the chemicals used in this investigation were of analytical grade. They were obtained from Department of Food Science and Technology, Rufus Giwa Polytechnic, Owo, Ondo State. The equipments were obtained from Department of Food Science and Technology, Rufus Giwa Polytechnic, Owo, Ondo State.


 Preparation of Carica papaya Seeds

The fruits were cut into two longitudinal halves and the seeds were removed by hand. The testa of the seeds were removed by squeezing the seeds between two fingers. The seeds were dried in an oven at 60ºC. The dried seeds were stored at -4ºC until required for analysis.




Table 1: Physio- chemical properties of Papaya seed oil and Groundnut oil





From the comparative examination of the physico chemical properties of papaya seed oil and groundnut oil above, it was showed that groundnut oil has a good saponification property, good quality and preservation status while papaya seed oil has a good properties such as FFA, Acid value, iodine value over groundnut oil and there is no significant difference in specific gravity. Therefore, it is concluded that papaya seed oil could be used for consumption in place of groundnut oil if properly refined and processed.


Based on the finding, the following are recommended for further knowledge and utilization of the oil.

  1. Before being considered adequate for food applications, toxicological studies need to be carried out to ascertain whether or not this oil is safe
  2. Information provided by the present study is of great importance for further chemical investigations of papaya seed oil and industrial utilization of the papaya seeds as a raw material to foods and cosmetics.


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  • Abdulazeez, A.M., Ameh, D.A., Ibrahim, S., Ayo, J. and Ambali, S.F. (2009). Effect of fermented and unfermented seed extracts of Carica papaya on pre-implantation embryo development in female Wistar rats (Rattus norvegicus). Scientific Res. Essay. 4(10):1080-1084.
  • Abdulazeez, M.A. (2008). Effect of fermented and unfermented seed extract of Carica papaya on implantation in Wistar rats (Rattus norvegicus). Thesis submitted to Department of Biochemistry, A.B.U Zaria.
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