1.1 Introduction
Cashew (Anacardium occidentale L.) is a perennial tree crop, originating from South America, and now widely grown in the tropics. Cashew is a multipurpose tree crop, from which almost all parts (roots, stem, bark, leaves, apples and nuts) are used. The nut is considered the most valuable product. In the past, cashew was considered as a hardy crop, which needed little attention in terms of management and pest control. Current research findings indicate that this is no longer the case and that it is frequently attacked by various pests. This chapter deals with a number of aspects related to plant breeding, crop improvement and pest management, as well as agronomic practices that are equally crucial for cashew nut production and quality.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Essential oils are volatile oils, which occur in some trees. They occur in the leaves, blossoms, fruits, trunks, stems and/or roots of the bearing trees. However, very few of the great number of essential oil bearing species are being used for commercial production of the oils. The cashew tree is evergreen, and serves as food to many in so many ways in that all the parts are consumable and they are highly medicinal. The trees are most frequent found in coasted areas. It grows up to 12 meters high and has a spread of 25 meters. Its extensive root system allows it to tolerate a wide range of moisture levels and soil types, although, commercial production is advisable only in well-drained, sandy, loam and red soil (Denny et al 2000).
A number of essential oils are exploited by chemical and allied industries as a source of specific compounds for subsequent transformation to a wide range of synthetic products such as aroma chemicals, flavours, vitamins and pesticides. They are also valuable in the manufacture of essential balms, medicated ointments, soaps, perfumes, shampoos and other cosmetics. Various methods exist for the recovery of essential oils, which include mechanical expression, effleurage, maceration, steam distillation, water distillation, water and steam distillation and supercritical fluid extraction. Most essential oils currently in use by cosmetic, food, perfumery and pharmaceutical industries in Nigeria are imported. Perhaps, this is due to the fact that there are virtually little or no local manufacturers of these all-important industrial intermediates in Nigeria.
Therefore, for the aforementioned numerous uses of essential oils coupled with the high cost of their importation, significant increase in demand by chemical and allied industries and availability of abundant raw materials in Nigeria, there is the need to develop appropriate technology for local production of essential oils. The main commercial product of the cashew trees is the nut. In the main producing area of East Africa and India, 95% or more of the apple crop is not eaten, as the taste is not popular. However, in some parts of South America and West Africa, local inhabitants regard the apple, rather than the nut kernel, as a delicacy. In Brazil, the apple is used to manufacture jams, and alcoholic drinks (Douglas, 2005).
The cashew fruit (Anacardium Occidentale the family of Anacardiaceae) is unusual in comparison with other trees nuts since the nut is outside the fruit. The cashew apple is an edible false fruits, attached to the externally boom nut by a stem. In its raw sate, the shell of the nut is leathery, not brittle. It contains the thick vesicant oil, a thin taste skin surrounds the kernel and keeps it separated form the inside of the shell. The primary products of cashew nuts are the kernels which have value as confectionery nuts. Cashew nut shell liquid (CNSL) is an important industrial raw material for resin manufacture and the shells can be burned to provide heat for the decorticating operation.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Extraction and Production of Essential Oil from Cashew Nuts.
1.3 Statement of Problems
Investigation revealed that the most important product of the cashew tree is the nut, which is used as confectionery. Cashew shell nut liquid (CNSL), which is of great industrial importance is obtained from the seed pericarp by steam distillation or extraction. When unprocessed or improperly roasted, the cashew nut is very astringent (Abitogun and Borokini, 2009); the complete roasting makes all the allergens inactive.
Cashew nut is a high value edible nut which yields two “Oils” one of these found, between the seed coat or pericarp and the nuts. Hence, this work intends to solve the problems of extraction and production of essential oil from cashew nuts. In the third world, mostly in the villages, people still depend on herbal medicine. From literature it is know that eating the apple or their tender leaves of the cashew plant helps to relieve diarrhea. In Guyana, the stem bark are cut off cooked overnight and used for diarrhea treatment. In other parts of the world, the roots, leaves and cashew nuts are used. Since diarrhea is wide spread in the hinter land, it is essential to find out if the extracted oil will have the same effect as the whole cotyledon of the nut.
1.4 Aim and Objectives of Study
The aim of the study is to investigate the Extraction and Production of Essential Oil From Cashew Nuts. In achieving this aim, the following specific objectives were laid out as follows:
- To determine the physical properties of the essential oil produced;
- To extract essential oil from cashew nuts;
- To examine the features of essential oil; and
- To determine the chemical properties of the essential oil produced.
1.5 Research Hypothesis
In order to pursue the objective of this study, the following generalized statements have been designed to guide and aids in obtaining the result for the experiment to be conducted. For this work, the null hypothesis will be represented with H0 while the alternative hypothesis will be represented with hypothesis H1.
Hypothesis One
- H0: There is no significant advancements have been made for the utilization of the cashew nut essential oil
- H1: There is significant advancements have been made for the utilization of the cashew nut essential oil
1.6 Significance of Study
The significance of this research cannot be overemphasized. This is because the research will reveal methods of extraction and production of essential oil from cashew nuts. It will also benefit student of science Laboratory Technology because it serves as a secondary material for students who will be interested in similar topic.
1.7 Scope of Study
The scope of this research is focused on the Extraction and Production of Essential Oil From Cashew Nuts.
1.8 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
1.9 Definition of Terms
Effect: a change which is a result or consequence of an action or other cause.
Cashew: It is a multipurpose tree crop, from which almost all parts (roots, stem, bark, leaves, apples and nuts) are used. The nut is considered the most valuable product.
