Determination of crude fiber

Determination of petroleum fiberDietary fiber abide be defined as sum of polysaccharides and lignin that argon not digested by human digestive enzymes. The major components of dietary fiber are cellulose, noncellulose such(prenominal) as hemicelluloses and pectin, lignin, and hydrocolloids (gums, mucilages, and algal polysaccharides). Human nourishmentstuffs contain mainly noncellulose polysaccharides, some cellulose and myopic lignin. The average proportions of noncelluloe polysaccharides. Cellulose and lignin for common foodstuff are about 70%, 20% and 10% respectively(Laura and other 2003).The crude fiber mode was developed in the 1850s to estimate indigestible carbohydrate in animal prevails. Since an easy election was not available, fiber in human foods was measured as crude fiber until the early 1970s (except for Southgate in England). Crude fiber rule is one of the gravimetric method that measures the organic food resiimputable remain after sequential digestion with 0.255N sulphuric stifling and 0.313N sodium hydroxide ancestors, followed by oven-drying at 104C overnight and ignition in muffle furnace at 600C for 3 hours. The compounds removed are predominantly protein, sugar, starch, lipids and portions of both the structural carbohydrates and lignin. Crude fiber method measures variable amounts of the cellulose and lignin in the sample, alone hemicelluloses, pectins, and added gums or hydrocolloids are solubilised and removed. Therefore, crude roughage measurement drastically underestimates dietary fibre in foods since it measures only cellulose and lignin. As a result, crude fiber method is only adequate for endeavor of fiber in animal feed product, but not suitable for human food abstract as lignin is significant to human health (James N.BeMiller 2003)Determination of carbohydrateCarbohydrates are main(prenominal) in food because carbohydrates provide energy, enhance immune function and bear out cellular communications. Carbohydrat es are converted into energy to allow our cells to function. There are two major types of carbohydrates such as complex carbohydrates and simple carbohydrates. convoluted carbohydrates are glycogen in human tissue and cellulose in seed down tissues. Simple carbohydrates are monosaccharide such as glucose, fructose, galactose and disaccharides standardised maltose, lactose and sucrose (DeWayne McCulley 2005). The most important sources of carbohydrates are plant food such as fruits, vegetables and grains. Milk and milk products contain the carbohydrates lactose (milk sugar) but meat, fish and poultry have no carbohydrate at all. iodine gram of carbohydrates has four calories. To find the number of calories from the carbohydrates in a serving, cipher the number of grams of carbohydrates by four. For example, one whole bagel has about 38 grams of carbohydrates, equal to about 152 calories (Carol Ann Rinzler 2006). The determination of carbohydrates is one of the most frequently i ndispensable analyses in the food analysis laboratory and has considerable application in nutritional and biochemical studies. The variety of food and beverage products from food manufacturers continues to expand. This variety, combines with raised expectations of quality and consistency from the consumer, has created a need for analytical methods that provide circumstantial data on the composition of both raw materials and final products. Analyses for carbohydrates must(prenominal) be applicable to simple ingredients, complex processed foods, and fractions or components separated in nutritional studies. (Eliasson, 2006) There are several methods of carbohydrate analysis and can be divided into physical methods and chemical method. Physical methods by and large determined some overall features of the sugars in food such as total carbohydrates. The physical methods include refractometry, polarimetry and hydrometry. Un wish well physical methods, chemical methods are able to dete rmined more than specific features, for example, reducing sugar. In this experiment, carbohydrates in foods were determined by difference after knowing the content of other food components. The accuracy of the by difference method depends on the determination of other food components and does not make any distinction amidst the available and nonavailable carbohydrates. The advantage of this method is carbohydrates content can be measured without carry out an experiment (Nollet 2004).Determination of Vitamin CAscorbic acid (vitamin C) which forms cementing mall such as collagen in the body is important in vex healing and increasing resistance to infections. This vitamin also enhances the absorption of non-heme iron and whitethorn protect against some cancers and cardiovascular disease. Milk contains only a little amount of ascorbic acid (0.94 mg per 100g milk). Processing or film to mania such as pasteurization reduces the vitamin C content of milk. The current RDA for vitam in C for most adults is 60mg per day (Gregory and others 1999). Besides, pregnant women need a moderate increase for vitamin C during last trimester to meet the needs of the growing fetus. The vitamin C content in food is strongly influenced by length of time on the shelf and in the storage and cooking practice likes the heating and exposure to copper or iron or to mildly alkaline conditions destroys the vitamin (World wellness Organization 1998).The AOAC method for determining vitamin C in food is found upon the reduction of the dye 2, 6-dichlorophenolindophenol (DCPIP) with ascorbic acid in an acid solution. DCPIP is used as the titrant because it only oxidizes ascorbic acid and not other substances that might be present. Besides, it acts as a self-indicator in the titration because it changes to another color when in excess analyte (ascorbic acid). In the oxidized form, DCPIP is purplish-blue in neutral or alkaline solution, and pink in acid solution the reduced form of dye is c olorless. The solution pull up stakes remain colorless as more DCPIP is added until all of the ascorbic acid has reacted. As soon as the next drop of DCPIP solution is added at the solution and the solution is turn to light red or pink due to the excess DCPIP, the end point of the titration is reached. Hence, the ascorbic acid is oxidized to dehydroascorbic acid by DCPIP solution. However, this method is not capable of determining dehydroascorbic acid content that presents more or less 80% of vitamin C activity shown by ascorbic acid. The plot below show the reaction between ascorbic acid and 2, 6-dichloroindophenol (DCPIP). (Ball 1997)Redox reaction between ascorbic acid (vitamin C) and 2, 6-dichlorophenolindophenol (DCPIP).Before using DCPIP to quantitatively measure vitamin C, the stringency of the DCPIP solution must be known. The concentration of DCPIP solution can be determined by react the DCPIP solution with a solution of ascorbic acid with a known concentration. This is known as standardizing the solution and it must be done before determine the concentration of vitamin C of sample. The vitamin is very allergic to oxidative deterioration, which is enhanced by high pH and by the front man of ferric and cupric ions. For this reason, the entire analytical procedure needs to be performed at low pH and in the presence of a chelating factor if necessary. (Ronald and Landen 2003) For example, ascorbic acid is extracted from food and titrated with the indicator in the presence of acid like oxalic acid. These acids are used to preserve the correct acidity for reaction and to void auto oxidation of ascorbic acid.1. James N.BeMiller. 2003. Carbohydrate Analysis. In S. Suzanne Nielsen. Food Analysis. tertiary ed. New York Kluwer Academic/Plenum Publishers. p144-169.2. Laura E. Matarese, Michele M. Gottschlich. 2003. Contemporary nutrition support practice a clinical guide. 2nd ed. ground forces Saunders. 173-175p.3. Carol Ann Rinzler. 2006. Nutrition fo r Dummies. 4th ed. USA Wiley Publishing. 102p.4. DeWayne McCulley. 2005. Death to Diabetes The Six Stages of Type 2 Diabetes Control Reversal. South Carolina BookSurge. 56p.5. 3. Ann-Charlotte Eliasson. 2006. Carbohydrates in food. 2nd Edition. USA CRC Press. 2-3p.6. Handbook of Food Analysis Physical mental picture and Nutrient Analysis. 2nd ed. USA Marcel Dekker, Inc. 387-393p.7. G. F. M. Ball. 1997. Bioavailability and analysis of vitamins in foods. united Kingdom Chapman Hall. 521-523 p.8. Gregory D. Miller, Judith K. Jarvis, Lois D. McBean. 1999. Handbook of dairy foods and nutrition. 2nd ed.USA CRC Press. 24p9. World Health Organization. 1998. Vitamin and mineral requirements in human nutrition. China Sun Fung. 135-137p.10. Ronald R.E and W.O.Landen, Jr, 1999. Vitamin Analysis. In S. Suzanne Nielsen. Food Analysis. tertiary edition. New York Kluwer Academic/Plenum Publishers. New York. p 182.