PRODUCTION OF COCONUT OIL FROM COCONUT

PRODUCTION OF COCONUT OIL FROM COCONUT

ABSTRACT

This study was carried out to extract coconut oil from coconut.  Coconut oil (Cocos nucifera L.) has a unique role in the diet as an important physiologically functional food. The health and nutritional benefits that can be derived from consuming coconut oil have been recognized in many parts of the world for centuries. There are few techniques for coconut oil extraction, such as physical, chemical, and fermentation or enzymatic processes using microbial inoculum as enzymatic starter. Starter with different concentration (1.0; 2.5; 5.0; and 10%) of microbial strains were added into coconut cream and allowed to be fermented for over night. The extracted oil was analyzed for further experiment, especially on its antibacterial activity. The maximum yield of 27.2% was achieved by adding 5.0% starter. Water content, acid value, FFA, and peroxide value of the fermented coconut oil were 0.3%, 0.45%, 0.22% and 2.54% respectively. A gas chromatogram showed that this fermented oil contained high lauric acid (46.82%), and 6.01% caprylic, 7.5% capric, 17.02% miristic, 7.21% palmitic, 3.11% palmitoleic, 5.41% stearic, and 1.3% linoleic acid, respectively. An inhibitory effect of such kind coconut oil which contains potential fatty acid against bacterial growth was further examined. It was found that this edible oil exhibited antibacterial activity to inhibit the growth of Bacillus subtilis, Escherichia coli, Pseudomonas fluorescence, Bacillus cereus and Salmonella; however it showed slightly inhibitory effect when it was exposed to Bacillus cereus and Escherichia coli.

CHAPTER ONE

1.0       Introduction

Oil is extracted from a number of fruits, nut and seed for use in cooking and soap making or as an ingredient in other foods such as boiled or fried food. Oil is a valuable product with universal demand and the possible income from oil extraction is therefore often enough to justify the relatively high cost of setting up and running small-scale oil milling business.

Coconut oil is an edible oil extracted from kernel or meat of matured coconut harvested from the palm (Cocos nucifera). It has various applications in food, medicine and industry (UNIFEM, 1987).

Coconut (Cocos nucifera) grown in about 93 countries in the area of 11.8million has produces 10.9million tones of copra equivalent. Coconuts provide food, drinks, medicine, health, shelter and aesthetics. Since every part of coconut is used for mankind, it is grown as tree of life, or rather “tree of nature” one of the natural product of coconut is that coconut oil has been used from time immemorial as foods, Food ingredient and functional foods, besides used in pharmaceuticals, nutriceuticals, cosmetics and industrial uses including bio fuel, It is known as miracle oil.

Historically, coconut and their extracted oil have served man as important foods for thousands of years. The use of coconut oil was advertised in the united state, in the popular cook book at the end of 19^th century. Both the health promoting attribute of coconut oil and those functional properties useful to the homemaker were recognized 100 years ago. These attributes, in addition to some new attributes should be great interest of producing as well as consuming countries (Ellis, 1997).

Coconut oil has been a life saver for many people. The health and nutritional benefit derived from coconut oil is unique and compelling (Enig, 1998) had stated that medium chain triglycerides, a fraction of coconut oil has been identified as an important, medically efficacious food. Indeed, diet for critically ill children, premature infants and hospitalized partners used medium chain triglycerides as principle source of fat. Coconut oil when used in usual diets containing all classes of fat proves to be anticholesterogenic.

Coconut oil can be extracted through dry or wet processing. The dry processing require the meat to be extracted from the meat and it is been dried using fire, sunlight or kilns to create copra. The copra is dried under sunlight for a maximum of seven days and a minimum of five days. While wet processing uses raw coconut rather than dried copra i.e. a fresh matured coconut. Different method can be used in extracting oil from coconut and the method must be efficient for the extraction in order to yield the desired result.                  

1.1       Historical Background

The coconut(Cocos nucifera) is a member of the family Arecaceae (palm family) and is one of the nature’s gifts to mankind (William, 1997).

It is the only accepted species in the genus Cocos, and is a large palm, growing up to 30m tall, with pinnate leaves 4–6 m long, and pinnae 60–90 cm long; old leaves break away cleanly, leaving the trunk smooth and the term coconut can refer to the entire coconut palm, the seed, or the fruit, which is not a botanical nut (World Wildlife Fund, 2010).

Coconut has been part of peoples’ diet and livelihoods in the tropical countries of Asia, the Pacific, South and Central America and Africa for thousands of years. In these areas, native meals are cooked with either coconut milk or coconut oil. The coconut palm is grown throughout the tropics for decoration, as well as for its many culinary and non-culinary uses; virtually every part of the coconut palm can be utilized by humans in some manner. However, the extent of cultivation in the tropics is threatening a number of habitats such as mangroves; an example of such damage to an ecoregion is in the Petenes mangroves of the Yucatan (Foale, 2003).

Coconut palms are believed to be largely cross-pollinated, although some dwarf varieties are self-pollinating. The meat of the coconut is the edible endosperm, located on the inner surface of the shell. Inside the endosperm layer, coconuts contain an edible clear liquid that is sweet, salty, or both (Fife, 2005).

Although coconut meat contains less fat than many oilseeds and nuts such as almonds, it is noted for its high amount of medium-chain saturated fat and about 90% of the fat found in coconut meat is saturated, a proportion exceeding that of foods such as lard, butter, and tallow. There has been some debate as to whether or not the saturated fat in coconuts is less unhealthy than other forms of saturated fat (see coconut oil). Like most nut meats, coconut meat contains less sugar and more protein than popular fruits such as bananas, apples and oranges. It is relatively high in minerals such as iron, phosphorus and zinc.

Coconut oil is extracted from the kernel or meat of matured coconut harvested from the coconut palm (Cocos nucifera). Throughout the tropical world it has provided the primary source of fat in the diets of millions of people for generations. It has various applications in food, medicine, and industry. Coconut oil is very heat stable so it makes an excellent cooking and frying oil. It has a smoke point of about 360°F (180°C). Because of its stability it is slow to oxidize and thus resistant to rancidity, lasting up to two years due to high saturated fat content. In the wet process, coconut milk is made first and then the oil is extracted from the milk (Fife, 2005).

Coconut kernel is shredded and mixed with water. Then it is pressed and the oil is extracted. The resulting oil/water mixture is left to sit and it separates into two layers, watery on the bottom, creamy on top. The thicker cream is decanted off the top and the original method of separation involved heating or fermenting the milk to separate the oil. This traditional method made a very unstable oil with a short shelf life meant for quick daily use. Due to its miscible nature coconut oil cannot be separated naturally from the cream (Ohler, 1984).

All high volume modern methods incorporate heating, fermentation, and or centrifugal force to separate the oil from the water. Some minor heating is generally done afterwards (often in a low temperature vacuum chamber) to drive off excess moisture and produce a more purified product and to extend shelf life. Proper harvesting of the coconut (the age of a coconut can be 2 to 20 months when picked; the time of harvesting makes a significant difference in the efficiency of the oil making process) and the use of a centrifuge process make the best final extracted product (Woodruff,1970).

1.2       Aim and Objectives of the Study

The main objective of this project is to extract coconut oil from coconut using fermentation or enzymatic processes with microbial inoculum as enzymatic starter