ryokawa619
please...somebody help me.... I'm left with only two days to answer the question...
Answer
It has three key properties that make it useful for melting point determination of organic compounds.
1. it is clear and you can see the M.Pt tube through it. It stays pretty clear on heating.
2. it can be heated to around 250C without boiling which is high enough to melt most organic compounds.
3. it does not catch fire when heated unless heated beyond the top recommended temperature.
i want know more about virgin coconut oil.?
samry siau
Answer
Refined Coconut Oil
Most commercial grade coconut oils are made from copra. Copra is basically the dried kernel (meat) of the coconut. It can be made by: smoke drying, sun drying, or kiln drying , or derivatives or a combination of these three. If standard copra is used as a starting material, the unrefined coconut oil extracted from copra is not suitable for consumption and must be purified, that is refined. This is because the way most copra is dried is not sanitary. The standard end product made from copra is RBD coconut oil. RBD stands for refined, bleached, and deodorized. High heat is used to deodorize the oil, and the oil is typically filtered through (bleaching) clays to remove impurities. Sodium hydroxide is generally used to remove free fatty acids and prolong shelf life. This is the most common way to mass-produce coconut oil. The older way of producing refined coconut oil was through physical/mechanical refining (see Tropical Traditions Expeller Pressed Coconut Oil.). More modern methods also use chemical solvents to extract all the oil from the copra for higher yields.
RBD oil is also sometimes hydrogenated or partially hydrogenated. This happens mostly in tropical climates, since the natural melting point of coconut oil is about 76 degrees F, and already naturally a solid in most colder climates. Since coconut oil is mostly saturated, there is little unsaturated oil left to hydrogenate. Hydrogenated oils contain trans fatty acids.
Virgin Coconut Oil
Virgin Coconut Oil can only be achieved by using fresh coconut meat or what is called non-copra. Chemicals and high heating are not used in further refining, since the natural, pure coconut oil is very stable with a shelf life of several years. There are currently two main processes of manufacturing Virgin Coconut Oil:
1. Quick drying of fresh coconut meat which is then used to press out the oil. Using this method, minimal heat is used to quick dry the coconut meat, and the oil is then pressed out via mechanical means.
2. Wet-milling. With this method the oil is extracted from fresh coconut meat without drying first. "Coconut milk" is expressed first by pressing. The oil is then further separated from the water. Methods which can be used to separate the oil from the water include boiling, fermentation, refrigeration, enzymes and mechanical centrifuge.
The method we use at Mt. Banahaw Health Products Corp. in the Philippines is the traditional fermentation method. The coconut milk expressed from the freshly harvested coconuts is fermented for 24-36 hours. During this time, the water separates from the oil. The oil is then slightly heated (less than boiling temperatures) for a short time (10-15 minutes) to remove moisture, and then filtered. The result is a clear coconut oil that retains the distinct scent and taste of coconuts. This is a traditional method of coconut oil extraction that has been used in the Philippines for hundreds, if not thousands of years. Laboratory tests show that this is a very high quality coconut oil, with the lauric acid content being 50 to 57%. This oil is not mass produced, but made by hand just as it has been done for hundreds of years. Our coconuts are certified organic according to strict USDA standards. In addition, all of our coconuts are hand-picked within 24 hours of harvest. Only those nuts that produce the highest quality coconut oil are chosen, while the rest of the crop is sold to copra dealers. Because of our extremely selective procedure for selecting the coconuts, we pay a higher price to the farmer. Almost all other virgin coconut oils on the market are mass-produced and do not take this kind of attention to detail that begins with choosing the right nuts. Also, the coconuts used to make our Virgin Coconut Oil are grown in very rural areas, generally far away from metropolitan areas. Since coconut trees grow just about everywhere in the Philippines, most coconut oils on the market are harvested from trees in metropolitan areas, because there is less cost to transport them to the place of manufacture. Many of our producers are in areas so remote, that if they did not use their coconuts to produce Virgin Coconut oil for us, no one would buy their coconuts because it would cost too much to transport them to manufacturing plants.
Delivering Virgin Coconut Oil to the Mt. Banahaw warehouse in 5-gallon pails. Many of our producers live in rural areas in coconut-producing communities where no roads exist, and draft animals like the water buffalo are used.
Bringing in young coconuts from the farm and loaded onto a jeepney to be transported to the market.
I love Tropical Traditions Virgin Coconut Oil, it is the best I have tried, and I will continue to use this oil forever. Kelly - Lander, WY
One of the main differences between Virgin Coconut oil and refined coconut oils is the scent and taste. All Virgin Coconut Oils retain the fresh scent and taste of coconuts, whereas the copra-based refined coconut oils have a bland taste due to the refining process. Some grades of refined copra-based oils are also now sold that have a coconut flavor, but are usually bitter and have a burnt taste to it. They are a form of "crude coconut oil" that has not undergone all of the deodorizing process, and they have a shorter shelf-life.
What is "Extra Virgin Coconut Oil?"
Some retailers and manufacturers of Virgin Coconut Oils, referring to one of the processes mentioned above, call their coconut oil "Extra Virgin Coconut Oil." But there are no other processes used to make coconut oil other than the ones mentioned above, so this classification is simply arbitrary. There is no official classification or difference between "virgin" and "extra virgin" as there is in the olive oil industry, since the two oils are completely different in fatty acid composition, harvesting procedures, and terminology.
Virgin Coconut Oil and Heat
There have been many claims made recently on the Internet that there are Virgin Coconut oils in the market that are processed without heat, and that these coconut oils are somehow superior to coconut oils that use some heat in the processing. Do these claims have any merit? Mt. Banahaw Health Products and Tropical Traditions has thoroughly researched this topic, and following are the results.
Some are claiming that there are "raw" Virgin Coconut oils that never see heat at temperatures above a certain temperature (usually slightly over 100 degrees F.) and therefore contain beneficial enzymes. However, unless one is purchasing a coconut oil that has been transported from the tropics in refrigerated containers, and is delivered to you in refrigerated delivery trucks, this is just simply not possible. To read our full explanation on why one does not want enzymes in their coconut oil anyway, see our full explanation here.
Mt. Banahaw Healthy Products Corp. was the first company to export "Virgin Coconut Oil" from the Philippines, using the traditional fermentation method as described above. Since those early days, many other producers have now entered into the local market in the Philippines with a variety of different "Virgin Coconut Oils" produced in many different ways. So in 2005 Professor Vermont P. Dia of the University of the Philippines conducted a study with some of his graduate students to analyze various Virgin Coconut Oils produced using different methods. Their results were published in December 2005, in The Philippine Agricultural Scientist, Vol. 88 No. 4, pages 462-475. The title of the article is "Comparative Physiochemical Characteristics of Virgin Coconut Oil." The results of this study have become the standard for Virgin Coconut Oil quality in the Philippines, and were published and implemented by both BFAD (Bureau of Food and Drugs) and PNS (Philippine National Standards).
They produced three batches of Virgin Coconut Oil in their laboratory using three different methods, and also analyzed six different commercial brands of Virgin Coconut Oil in the Philippines. The three batches they produced in their laboratory were all produced with little or no heat, some using refrigeration and never going above 47 degrees Celsius (less than 117 degrees F.) The values that were tested in all these Virgin Coconuts oils were: melting point, gravity, saponification, iodine, free fatty acid (FFA), peroxide value, moisture content, fatty acid composition, tocopherols, and total phenolic content. Their results found that: "while the VCOs produced by the three methods and using different varieties had some differences in chemical and quality properties, these differences may not be large enough to significantly affect the overall quality of the VCO. Further, their levels are still within the CODEX standards for coconut oil." In the 6 commercial brands they tested (where it is routinely assumed today that "no heat" is better), they found some had values that exceeded the limits of standards in areas like moisture content and FFA. The study was concluded by stating: "The effect of higher temperature (>50 C) during processing on the quality of VCO is likewise important to determine and is being investigated."
Mt. Banahaw Health Products Corp.'s Virgin Coconut Oil is not sold in the local Philippine market, as it is produced exclusively for Tropical Traditions, so we decided to send a sample to Professor Dia to analyze. We already knew that our VCO consistently tested well within standards for moisture and FFA (our moisture levels, for example, have ranged from 0.06 to 0.08 percent in 2006, where industry standards for refined coconut oils are .10%), but we had never tested for phenolic acid, an antioxidant usually associated with products like Green Tea and Olive Oil. Some have theorized that it is the polyphenols in Virgin Coconut Oil that differentiate its quality from regular refined coconut oil, where polyphenols are generally missing. The three samples Professor Dia and his students produced in the laboratory, and the six commercial samples they tested had a range of 6.29 to 8.38 mg gallic acid of phenolic content per gram of oil. When they tested the VCO of Mt. Banahaw Health Products Corp., the values were 13.21 to 13.43 mg gallic acid per gram of oil! (See Professor Dia's statement on Mt. Banahaw Health Products VCO here.) We repeated this test several times on different batches of our Virgin Coconut Oil to verify the high results. In some cases, our phenolic content was more than twice as high as other Virgin Coconut Oils they had tested.
So in terms of empirical evidence, there is no evidence anywhere that we can find that Virgin Coconut Oil produced with "no heat" is superior in any way to the traditional method of producing Virgin Coconut Oil that is used for the Tropical Traditions brand of VCO, which has been sold to hundreds of thousands of people in the US market and around the world for six years now. On the contrary, Professor Dia has verified that at least with phenolic content, our VCO tested higher than any other VCO they had tested in the Philippines. While it has not been proven that the small use of heat that the traditional fermentation method uses at the end of its process to remove moisture and impurities is the cause of these high values (we are still testing for that - could it be that without some heat there are some undesirable enzymes from the coconut meat present in the oil that are breaking down some of the beneficial properties of VCO??), it at least shows that if the methods and quality of coconuts that Mt. Banahaw Health Products Corp. producers practice are followed, that the use of heat in the process has no negative affect on the quality of Virgin Coconut Oil produced.
Powered by Yahoo! Answers
