Puryfying Used Cooking Oil

Abstract
The researchers are trying to figure out the effects of sedimentation, activated carbon, and decantation and boiling on purifying used coconut, palm and vegetable oil. The researcher’s experiment resulted to the change of appearance, odour and viscosity of each type of oil. The now purified cooking oil is faster to heat which makes cooking easier, faster and more efficient. The purified oil is quite beneficial however it does not take in as much taste as the unpurified ones. Overall the experiment was very successful in terms of finding the positive differences in each type of oils. The vegetable oil was the best product of all the processes because it had shown the best improvement in all aspects including appearance, odour and viscosity compared to the coconut and the palm oil in the experiment. This study can benefit people who love to cook.

Acknowledgements
The researchers would like to thank the following for making this study successful:
• The Anico family for openly welcoming the researchers into their home without hesitation.
• Ms. Michelle Baldevarona for being patient in helping with the SIP in every step of the way.
• Most of all, the Heavenly Father for blessing the researchers with minds that are capable of interpreting the information taught and transferring it to useful knowledge.

Chapter 1
Introduction
Background of the Study In the commercial world of fast food restaurants and Filipino homes, lessening expenses is one their main goals. Most fast food restaurants, such as Jollibee and McDonald’s, try to lessen expenses by reusing cooking oil. More than not, they reuse cooking oil without making sure that it is still sanitary and healthy to use in cooking. Because most Filipino dishes include the use of cooking oil, it is a primary ingredient in many dishes. Therefore, many health concerns are raised, such as increase of cholesterol due to the reused fats present when cooking oil is reused without ensuring its sanitary and nutritional value. Cooking oils undergo a complex series of changes and reactions during heating and frying. Used cooking oils could be purified by removing the odour, undesirable taste and colour substances. Activated carbon, the process of decantation, sedimentation and boiling are potential means of improving the quality of the used edible cooking oils.

Statement of the Problem Will sedimentation, activated carbon, boiling and decantation purify coconut, palm and vegetable oil? Which oil is the best product from the purification processes?

Hypothesis Purified cooking oil is equitable with unpurified cooking oil in terms of content and quality such as appearance, odour and viscosity.
Definition of Terms
Activated Carbon - is a form of carbon processed to be riddled with small, low-volume pores that increase the surface area available for adsorption or chemical reactions.
Coconut Oil - an edible oil extracted from the kernel or meat of matured coconuts harvested from the coconut palm
Decantation - is a process for the separation of mixtures, by removing a top layer of liquid from which a precipitate has settled.
Palm Oil – is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palms
Sedimentation – natural process where solid materials sink to the bottom given a period of time
Vegetable Oil - is a triglyceride extracted from a plant
Significance of the Study The study will benefit people who use cooking oil to prepare meals. This will not only save them money but it can also ensure them that their food would still be edible due to the fact that reused cooking oil can easily become rancid (spoiled) and deteriorated to the point it produces undesirable flavours and odours. Besides ruining what would have been a perfectly good meal, rancid oils also contain free radicals that are potentially carcinogenic.
Scope and Limitation This study covered the purification of used cooking oils through the use of activated carbon, the process of decantation and of boiling. The researchers used vegetable oil, palm oil and coconut oil to be experimented on. Variables such as the amount of cooking oil used, the length it took to coo, the temperature and food used to cook were controlled. On the other hand, the manipulated variables were the types of cooking oil.
Chapter 2
Review of Related Literature
Uses and Effects Filipinos are fond of using cooking oil in their homes. They are also conscious of saving money by reusing these oils. But when cooking oils are reused without purifying it, some health hazards may occur. One of these is the formation of 4-hydroxy-trans-2-nonenal (HNE) which is due to the food particles left from the previous food cooked which are reheated again. HNE can cause cardiovascular disease, stroke, various liver disorders, and cancer.
Activated Carbon Activated carbon is a form of carbon processed to be riddled with small, low-volume pores that increases its absorption of liquids when passed through it. This can remove the unwanted food particles and further purify it.
Sedimentation
Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained, and come to rest against a barrier.
Decantation
Decantation is a process for the separation of mixtures, by removing a top layer of liquid from which a precipitate has settled. Usually a small amount of solution must be left in the container, and care must be taken to prevent a small amount of precipitate from flowing with the solution out of the container. It is frequently used to purify a liquid by separating it from a suspension of insoluble particles.
Coconut Oil Coconut oil is an edible oil extracted from the kernel or meat of matured coconuts harvested from the coconut palm (Cocos nucifera). It has various applications in food, medicine, and industry. Coconut oil is commonly used in cooking, especially for frying and is a common flavor in many South Asian curries. It has been used for cooking (in tropical parts of the world) for thousands of years. Coconut oil is used by movie theatre chains to pop popcorn, adding a large amount of saturated fat in the process.
Palm Oil Palm oil (also known as dendê oil, from Portuguese) is an edible vegetable oil derived from mesocarp (reddish pulp) of the fruit of the oil palms. Palm oil is naturally reddish in color because of a high beta-carotene content. It is not to be confused with palm kernel oil derived from the kernel of the same fruit, or coconut oil derived from the kernel of the coconut palm (Cocos nucifera). The differences are in color (raw palm kernel oil lacks carotenoids and is not red), and in saturated fat content: Palm mesocarp oil is 41% saturated, while Palm Kernel oil and Coconut oil are 81% and 86% saturated respectively.
Vegetable Oil A vegetable oil is a triglyceride extracted from a plant. Such oils have been part of human culture for millennia. The term "vegetable oil" can be narrowly defined as referring only to substances that are liquid at room temperature, or broadly defined without regard to a substance's state of matter at a given temperature. For this reason, vegetable oils that are solid at room temperature are sometimes called vegetable fats.
Viscosity
The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal notion of "thickness”. Viscosity is due to the friction between neighbouring particles in a fluid that are moving at different velocities.
Chapter 3 Methodology
Subject of the Study This study made us of three kinds of cooking oil which are mainly used in Filipino homes. These cooking oils are namely vegetable oil, palm oil and coconut oil.
Materials
¼ cup of vegetable oil
¼ cup of palm oil
¼ cup of coconut oil
Activated carbon
Bottle where the decantation process will take place
Pot where boiling can happen

Procedures
1) After the cooking oil has been used, let the oil stand for a while so that the food particles can settle at the bottom.
2) Pour it through a bottle which in the middle contains activated carbon and has holes at the bottom for the oil to pass through.
3) When you've removed the solids and particulates, pour an amount of water equal to the volume of oil into a large pot or kettle with deep sides. Pour in your oil. Add about 1/2 teaspoon of salt per quart of total liquid to the pot.
4) Bring the oil and water mixture to the boil, and then boil it hard for about 5 to 10 minutes. The darker, more scorched, and/or more strongly flavored the oil, the longer you should boil the mixture.
5) Remove from the heat, and set aside to settle out. It takes about 10 to 30 minutes for the oil to completely separate and come to the top.
6) Pour off the water portion as completely as possible and discard.
7) Put the oil portion back into the deep pot or kettle. Over medium heat, bring to the boil (which for oil is hotter, obviously, than for water. Reduce heat until it is boiling and popping a bit, but slowly. The goal here is to evaporate all of the retained water. When the oil becomes very clear looking and no longer makes any sound (no popping or sizzling sounds), has no more bubbles rising, and no more steam comes to the top, it's done.
8) Allow to cool, then bottle in an airtight container for reuse.

Chapter 4
Presentation, Analysis and Interpretation of Data
Table 1: Observation after Cooking Oils Used and After the Purification Process
Type of Cooking Oil Appearance Odour
Unpurified Vegetable Oil Looks like regular cooking oil Contains a subtle scent of something burnt
Purified Vegetable Oil Very clear yellow color Smells like original vegetable oil prior to being used
Unpurified Palm Oil Very dark yellowish-brown color Contains a subtle scent of hotdog
Purified Palm Oil Slightly lighter shade than previous color Still contains a subtle scent of hotdog
Unpurified Coconut Oil Murky yellowish-brown color Contains a subtle scent of hotdog
Purified Coconut Oil Murky light yellow color Contains a subtle scent that can’t be indentified Major variations were observed before the oils were cooked and after the oils were purified with the processes of sedimentation, activated carbon, decantation and boiling using 6 regular sized hotdogs which were cooked with the temperature between 180 degrees Celsius to 190 degrees Celsius (medium heat) in the span of 5 minutes.

Table 2: Viscosity Test
Type of Oil 1st Trial 2nd Trial 3rd Trial Average
Unpurified Coconut Oil 1.28 secs 0.98 secs 1.20 secs 1.15 secs
Unpurified Palm Oil 0.99 secs 1.15 secs 1.18 secs 1.11 secs
Unpurified Vegetable Oil 1.10 secs 0.97 secs 1.15 secs 1.07 secs
Purified Coconut Oil 0.95 secs 1.03 secs 0.91 secs 0.96 secs
Purified Palm Oil 1.10 secs 0.93 secs 0.96 secs 1.00 secs
Purified Vegetable Oil 0.97 secs 1.06 secs 0.94 secs 0.99 secs
The test was done with 100ml of different cooking oils, both purified and unpurified. The weight dropped into each of the container weighed 50grams. The most viscous liquid was the unpurified cooking oils and the unpurified was the lesser viscous one. The viscosity of the cooking oils affects how fast it takes to heat it. The more viscous a substance is, the longer it will it take to heat it. Although less viscous oils are faster to heat, foods cooked in it do not take in as much as the taste of the oil compared to the more viscous one. The purified oils were less viscous due to the purification processes done with it.

Chapter 5
Conclusion and Recommendation
Summary
The outcome of the researchers’ purification of the cooking oils deemed to be successful. These positive differences were proven in the observation table and viscosity test. The three oils used, mainly coconut, palm and vegetable, all showed these differences in their appearance, odour, and viscosity.

Conclusion Our experiment proved to be successful in terms of finding key differences in both the used and purified cooking oils. Based on the tables presented; there were significant differences between the unpurified cooking oil and the purified cooking oil in terms of its colour, odour and viscosity. The purified cooking oils; however, proved to be more beneficial in those different aspects. But overall, it was the vegetable oil that was the best product of our purification process because it had the most improvement in appearance, odour and had the lesser change in viscosity compared to the other two.

Recommendations For future use and investigation, the researches recommend that a wider variety of oils, such as olive, canola and peanut, should be tested. The researchers also recommend that more purification processes should be tested with the oils to further purify it. And lastly, a nutritionist is recommended to tests the nutritive value of these oils whether or not they have changed after being used and after purifying it.