Discussion:
Acidity number or acid value is defined as the mass of sodium hydroxide expressed in milligram used to neutralize one gram of acidic substance. This measurement is very important in order to understand the substance’s long term stability and corrosiveness in order to compare the quality of the oil. Fats are converted into fatty acid and glycerol during rancidification and increasing acidity of the sample. More sodium hydroxide is needed to neutralize the acid, and hence acidity number increases. (Peter.J.W, 2007) Therefore, the smaller the acidity number, the higher the quality of the oil. Free fatty acids concentration affects oil recovery and it determines the grade and price of the oil. Rancidification lowers nutritional value
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of the food and it may cause health diseases. Besides, the acidity number is also affected by the freshness of the oil. The oil will undergo many rancidification as the time passes. In this experiment, we express our acidity number as the percentage of free fatty acids (%) by using the formula given. In this experiment, phenolphthalein acts as indicator in acid-base titrations.
As the sodium hydroxide is added to the oil sample, the free fatty acids will undergone neutralization to form sodium carboxylate and water. Purple color can be observed due to alkaline and must last for 10 seconds to resemble as an endpoint of the titration.
Based on the Table 2, the A4 oil sample has the highest free fatty acids among all the six oil samples, followed by A2, A1, A3, A6 and A5. Therefore, A5 oil sample can be said that it has the highest quality. By comparing the results given, we have found some possible oil for our oil samples, A3 and A4. According to Peter J.W (2007), the possible oil for A3 and A4 are refined olive oil and soybean oil respectively.
According to Frank D.G (1994), acid value could be determined by the potentiometric method. Potentiometric titration uses an electrode to detect the change of electric potential instead of phenolphthalein. This is a more accurate and common method for highly colored oil or fats. The free fatty acids are in non-aqueous medium, titrating with a solution of potassium hydroxide in isopropanol. There are other numerous methods to determine acid value, such as Thermometric titration, measurement of metal-fatty acid complexes, enzymatic methods, methods using a fatty acid binding protein and spectroscopic methods (Cyberlipid, n.d). Chemical titration is suitable for this experiment because it is low in cost, simple oil samples
and does not need much technique and skills. There are some precautions for titration that have to be followed in order to increase the accurateness of the experiment. Firstly, the air bubbles in the nozzle of the burette has to be eliminated before taking any reading. The burette has to be checked for any leakage before the experiment begins. The drops of phenolphthalein should be fixed to ensure the consistency of the experiment. To prevent the dilution of sodium hydroxide due to water residue in the burette and mixing of other substance, the burette can be rinsed with sodium hydroxide solution. Conclusions: Based on the results tabulated, the acidity number of the oil samples are arranged in ascending order as below: A4 > A2 > A1 > A3 > A6 > A5
Compress the safety bulb, hold it firmly against the end of the pipette. Then release the bulb and allow it to draw the liquid into the pipette.
This pH homeostasis lab is used to show how acids and bases react when submerged into different solutions - water, a homogenate, and a buffer. A homogenate is blended up water and the cell tissue. They are used to show how much pH the cells have when adding an acid or base to it. A buffer is a solution that doesn’t change it’s pH level, even when acid or base is added to it. They are important to help all living things maintain homeostasis.
To uncover organic compounds like carbohydrates, lipids, proteins and nucleic acid, by using tests like Benedict, Lugol, Biuret and Beta Carotene. Each test was used to determine the presents of different organic molecules in substances. The substances that were tested for in each unknown sample were sugars, starches, fats, and oils. Moreover, carbohydrates are divided into two categories, simple and complex sugars. Additionally, for nonreducing sugars, according to Stanley R. Benedict, the bond is broken only by high heat to make make the molecules have a free aldehydes (Benedict). As for Lipids, there are two categories saturated and unsaturated fats. One of the difference is that saturated fats are mostly solids and have no double bond (Campbell Biology 73). The Beta Carotene test works by dissolving in a lipid, thus giving it color to make it visible. Moreover, proteins are made out of amino acids that are linked by a polypeptide bond (Campbell Biology 75). The purpose of this experiment was to determine whether an unknown class sample or food sample had any carbohydrates, lipids, or proteins in it. The expected result of the lab was that some substances would be present while other would be absent.
The weight of the final product was 0.979 grams. A nucleophile is an atom or molecule that wants to donate a pair of electrons. An electrophile is an atom or molecule that wants to accept a pair of electrons. In this reaction, the carboxylic acid (m-Toluic acid), is converted into an acyl chlorosulfite intermediate. The chlorosulfite intermediate reacts with a HCL. This yields an acid chloride (m-Toluyl chloride). Then diethylamine reacts with the acid chloride and this yields N,N-Diethyl-m-Toluamide.
This lab contains two different procedures to titrating vinegar. One procedure uses phenolphthalein while the other uses a pH meter. Bothe procedures can be found on “An Analysis of a Household Acid: Titrating Vinegar” by the Department of Chemistry at APSU.
Sesame seed oil: This oil is packed with B-complex vitamins, which is essential if you have an autoimmune or chronic disease that could impact the levels of vitamin B in your body. Vitamin B is essential for optimal health. It is also very high in the antioxidant vitamin E, which plays a part in the prevention of heart disease and
...nerated and replaced by fat. Recently, specific compounds in the oil have been identified, they produce regeneration that is even more amazing than that produced by the oil itself. (Gerras, 1056)
4. Lorenzo’s Oil is 4 parts oleic acid to 1 part erucic acid. It forces enzymes in the body to use oleic acid instead of saturated fatty acids. It turns off the "synthesis" spout in the sink. (The other spout is the "intake" spout from food that is eaten.
The citric acid cycle is an amphibolic pathway. It utilises both anabolic and catabolic reactions; the first reaction of the cycle, in which oxaloacetate (a four carbon compound) condenses with acetate (a two carbon compound) to form citrate (a six carbon compound) is typically anabolic. The production of the isomeric isocitrate is simply intramolecular rearrangement. The subsequent two reactions are typically catabolic, producing succinate (a four carbon compound), which is then oxidised, forming fumarate (a four carbon compound). Water addition produces malate and then oxidised for regeneration of oxaloacetate. Thus the cycle can be seen to exhibit both anabolic and catabolic processes to form its intermediates.
Before you go on to try any other type of oil (or really any other type of food), cleanse your palate with water and slices of green apple
Fatty acids such as linoleic acid, linolenic acid and arachidonic acid are known as essential fatty acid because they cannot be synthesized in the body so must be supplied in the food. Human being lacks the ability to introduce double bonds in fatty acids beyond carbons 9 & 10. About 20 different fatty acids are synthesized from the two essential fatty acids linoleic acid and linolenic acid. Omega three fatty acid is synthesized from linolenic acid and omega six fatty acid is synthesized from linolic acid.
The crude extract obtained by solvent extraction was subjected to various qualitative tests to detect the presence of common chemical constituents as:
1. The labels have fallen off of three bottles thought to contain hydrochloric acid, or sodium chloride solution, or sodium hydroxide solution. Describe a simple experiment which would allow you to determine which bottle contains which solution.
...eicosapentaenoic acid), and ALA (alpha-linolenic acid) are considered to be the three main fatty acids.
The actual, theoretical, and percent yield of sodium chloride was found. Sodium Carbonate was mixed with hydrochloric acid and the liquid was boiled until there was nothing left. The result was the production of salt, or sodium chloride.