CHAPTER ONE

1.0  INTRODUCTION

1.1    Background of the Study

Persea americana mill or Avocado is a tropical native American fruit. It belongs to the Lauraceae family. The name ‘Avocado’ has been derived from the Aztec word ‘ahucatl’. ‘Alligator pear’ and ‘butter fruit’ are its’ alternative names. It has been traditionally cultivated for food and medicinal purposes due to its high nutrition content as well as for its therapeutic properties. The earliest archeological evidence of this fruit dates back to 8^th century BC, where its seeds were found buried with a mummy, in Peru. Since then it has been used for the treatment of scabies, dander and ergotism by Mexican folk and Saint Antonius respectively in ethnomedicine. It was also used by women in the form of an ointment and also for treating skin eruptions. During the mid-1800’s, the cultivation of Persea Americana spread across Asia. Today, it cultivated and harvested worldwide.

The general definition of spreads include, but not limited to, spreads made from edible vegetable oil or animal fat or a combination of both such as margarine, cheese and butter and those obtained from fruits and vegetables such as jams, preserves and marmalades. It is largely known that margarine is a water-in-oil emulsion. Margarine consists of a continuous oil phase and with a finely dispersed discontinuous aqueous phase. Butter is perhaps the traditional spread developed since the inception of ancient food technology and its production technology has since not changed much. It is obtained by churning the cream that has been separated from warm cow’s milk to a product consisting of unaltered fat globules and moisture droplets embedded in a continuous phase of butterfat. From the studies of Pearson (1970) and Man (2002), butter contains butterfat, water and curd which is made up of casein, lactose and mineral matter. Another variety of spread is cheese which is mainly made from curd produced from the coagulation of souring milk. The souring is done by rennin, an enzyme obtained from the inner lining of the fourth stomach of the calf (Man, 2002).

Jam, jelly and marmalade preparations constitute yet another category of spread. The basic principle of jam and marmalade manufacture is the boiling together of fruit, sugars and water. For marmalade, the peel is cooked separately prior to mixing in. Jelly manufacture involves boiling the fruit with water and then the extract after filtration is boiled with the sugars (Kirk and Sawyer, 1991).

Many researchers discuss the nutritional value of margarine and other spreads largely around two components. These are the total amount of fat and the types of fat (saturated fat, trans-fat) as components of the formulation. It has been concluded by some researchers that the saturated fatty acids in triglycerides contribute to elevated blood cholesterol levels (Keys et al., 1965; Mensink et al., 2003; EFSA, 2004; EFSA, 2005; IoM, 2005), which in turn has often been linked to cardiovascular diseases. It has been observed that firmer margarines contain more saturated fat (Bruijne and Bot; 1999).

Willet et al., (1993), Hu et al., (1997) and Hayakawa et al., (2000) have also indicated a strong link between earlier death and consumption of high amounts of trans-fats which had been common in many spread formulations not quite too long ago. Trans-fats which do not occur naturally in vegetable fats are a consequence of partial hydrogenation of the oils, a requirement for some spread formulation procedures. According to some researchers Duijn, (2005) and Floter and Duijn, (2006) many industries have gradually moved away from using partially hydrogenated oils since the mid-nineties and now produce new spreads that contain less or no trans fats.

Though it has been proven that the intake of cholesterol has less effect on high blood cholesterol levels than saturated fat, the Food and Drugs Administration (FDA) of the United States of America has warned that healthy people should not consume more than 200 mg of cholesterol per day. However butter which contains high levels of cholesterol which is rapidly consumed heartily several times daily in the form of the varied spreads. Though margarine may contain no cholesterol due to their preparation procedures, the abundant saturated fat in margarine induces the bad type of cholesterol (low density lipoproteins) in the course of human metabolisms (Sebedio and Christie, 1998).

Margarines and other spreads excluding butter are however, important sources of vitamin E and, they contribute 14 % of total vitamin E intake in adults, 17 % in boys and 16 % in girls in the United Kingdom (British Nutrition Foundation, 2004). Possibly this may be the case in many affluent societies which many countries are now aspiring to become. For instance, there are various types of spread ranging from cheese, butter, margarine to fruit spreads on the Nigerian market (Mpere, (2008), Personal communication).

Due to problems associated with consumption of such as cheeses and margarines, alternatives which can deliver the functionalities required in traditional spreads with less nutritional problems are being sought. Persea americana fruit also known as avocado pear or alligator pear, comes in handy. Avocado pear is a seasonal fruit and native to the tropics and sub-tropics such as tropical America, Far Asia and Cuba (Purseglove, 1968; Pamplona-Roger, 2007). Purseglove (1968) has described the flesh of the fruit of the avocado as generally pale yellowish-green and softly succulent with buttery consistency even though inferior varieties may be fibrous in nature.

It is well known that avocado fruits ripen best when they have been detached from the tree. On ripening it yields to gentle, palm pressure and can be stored in the refrigerator for several days but once the flesh is cut and exposed they tend to brown rapidly due to enzymatic browning reactions (oxidation of the iron salts) (Pamplona-Roger, 2007). It has been observed that the darkening or browning process can be lessened when the unused portion of an avocado pear is covered with a plastic wrap, removing as much air as possible. Studies have shown that avocados do not freeze well but avocado puree can be frozen, although it may be slightly watery when thawed (Morton, 1987).

Avocados are very nutritious, high in unsaturated fat and at their buttery best when used in raw preparations but when they are cooked for long periods, their delicate flavour is diminished and in some instances they can become bitter (Purseglove, 1968; Morton, 1987). Avocado is thought to promote physical beauty when applied to the skin and is therefore used in cosmetics formulations and as an aphrodisiac (Purseglove, 1968; Bergh, 1992).

1.2    Statement of the Problem

1.3    Objectives of the Study

1. To examine the effect of medicinal and health values of avocado pear fruits among health care workers
2. To examine the effect of nutritional values of avocado pear fruits among health care workers
3. To examine the effect of cosmetic values of avocado pear fruits among health care workers

1.4    Research questions

1. What is the effect of medicinal and health values of avocado pear fruits among health care workers
2. What is the effect of nutritional values of avocado pear fruits among health care workers
3. What is the examine effect of cosmetic values of avocado pear fruits among health care workers

1.5    Hypothesis

1. There is no significant effect of medicinal and health values of avocado pear fruits among health care workers
2. There is no significant effect of nutritional values of avocado pear fruits among health care workers
3. There is no significant effect of cosmetic values of avocado pear fruits among health care workers

1.6    Significance of the Study

The empirical findings of this study offers relevant policy insights to stakeholders such as NGOs, agricultural marketing firms, group members and county government in enhancing such marketing groups. First, information on group dynamics will help to facilitate NGOs in their decisions regarding planning, organizing and provision of group trainings, funding and other incentives.

The affiliated agricultural marketing firms would utilize the findings to make evidence- based decisions in contractual terms and agreement processes, planning and organizing their collective marketing days and dispatching the members‟ earnings from group sales.

1.7    Delimitation of the Study

          In every research work, it is likely that the researcher may encounter some limitations. The researcher encountered some challenges during the period of carrying out this research. Some of these challenges include the dearth of materials for a proper and effective research work constituted a major limitation. Again, how to get the true and required information from the students through questionnaire also constituted a constraint in the study.

          Finally, there was the problem of convincing the health care workers on the primary objectives of the questionnaire so as to give the true and required information. However, the intervention of the clerks in the facility who took time to clear the air and convince his workers helped the investigator to administer the instrument successfully.