Testing Food for Nutrients
Purpose
The purpose of this experiment was to find out the nutrient content of unidentified food samples and to use chemical reagents to see if the unidentified foods for sugar, starch, protein and fat (lipid) content. After comparing the color changes in each unknown substance then you will be able to see the amount of sugar, starch, protein or fat there is in the unknown substance.
Introduction
Carbohydrates are used for energy and structural support in cell walls of plants and exoskeletons of crustaceans and insects. They are also used to make cell structures and can make a large group of chemical compounds. Carbohydrates are also made up of carbon, hydrogen and oxygen. The testing solution for carbohydrates is Benedict and iodine. Next is proteins, they help bulk up all solid materials inside your body, such as your muscle, hair, skin, and inside organs. Proteins also make up some hormones which help with the chemical control in the body. They
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Materials
• Glass test tubes/rods
• Safety googles
• Burner
• Brown paper
Procedure
Testing for Carbohydrates: sugar
1. Place 5 test tubes into a rack and then label them 1-5.
2. Add the unknown into their own test tube, about 20 drops.
3. Add about 5 drops of benedict into each test tube.
4. Mix each one with a glass rod and always make sure to wipe the glass rod after each use.
5. Carefully heat the test tubes in the heated bath of water for 5 minutes.
6. After carefully taking them out, observe each test tubes color and then fill Table 2 with the results. Testing for Carbohydrates: starch
1. Place 5 test tubes into a rack and then label them 1-5.
2. Add 20 drops of the unknown into the labeled tubes.
3. Then add about 1 – 2 drops of Lugol’s solution into each test
The purpose of this lab was to test different substances using various procedures to see what biomolecules were present and ultimately find out what restaurant Anna Lyza had eaten at before she died. For the first control test, we used vegetable oil to test for lipids. So, if the solution does not contain lipids, it does not become translucent when placed onto a paper bag square and held up to a light. So, it is a negative result. However, in the presence of lipids, the solution will become translucent when placed onto a paper bag square and held up to a light. Therefore in this case, the result is positive. On the other hand, we used albumin egg to test for proteins in another control test. If the solution does not contain proteins, it will not experience any color change and so it is a negative result. When there are proteins existing in the solution, it will turn bluish/purplish and for this reason it is a positive result. Furthermore in the third control test, we used dextrose to test for simple carbohydrates such as glucose. If the solution does not contain simple carbohydrates, it will not undergo any color change and will remain a blue color. So, it is a negative result in this circumstance. If there are simple carbohydrates present in the solution, the solution will turn reddish and so the result is positive. For the last control test, we used starch solution to test
2. Four unknown samples were included in the lab kit: flax seed meal, potato starch, egg whites, and dried milk. Using the results of the biochemical testing, determine which number corresponds to the correct unknown. (8 points)
My unknown organism #6 is Morganella morganii, which is a gram-negative bacillus rods commonly found in the environment and also in the intestinal tracts of humans, mammals, and reptiles as a normal flora. (3, 5) This bacterium Morganella morganii, was first discovered in the 1906 by a British bacteriologist named H. de R. Morgan. (2) Despite its wide distribution, it is an uncommon cause of community-acquired infection and is most often encountered inpostoperative and other nosocomial settings. (2, 3) Morganella morganii infections respond well to appropriate antibiotic therapy; however, its
7)a) You would do the Benedict’s reagent test for simple sugars and the Lugol’s solution or Iodine test for polysaccharides and starch. To test the lipids you would use the Sudan iV test and Biurets reagent test for protein.
Carbohydrates are composed of carbon, hydrogen, and oxygen. Carbohydrates can come from fruits, vegetables, and grains. There are two different kinds of carbohydrates. The first being simple carbohydrates, which are sugars. Glucose, fructose, and galactose fall under the sugar category. Then you have your complex carbohydrates, which are starch in grains, glycogen stored in our muscles, and fiber. When it comes to energy within our body glucose is a major source of energy. When our body does not get enough carbohydrates to supply enough glucose, our body will make glucose from proteins. I applied this to my life by making sure I eat fruits, vegetables, and grains to get my carbohydrates every single
main functions - primary energy source, fat and protein metabolism, energy reserves in stored glycogen, blood glucose fuels brain and CNS
Analysis: In this experiment, every substance tested positive for at least 1 organic compound. Corn oil tested positive for lipids. Honey and oats tested positive for starch. Honey, apple juice, and unknown 1 tested positive for sugar. Egg white, gelatin, and unknown 2 all tested positive for proteins. So, not a single substance didn't test positive for at least 1 organic compound. All the indicators used in this experiment change color when in the presence of a compound; therefore, they chemically react with the compound. No errors were made during this experiment
Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of the very nature of this ubiquity, it is important to be able to determine between different strains of bacteria. An example of this is determining the causative agent for a disease so that the patient will be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic infections in places outside of the digestive tract to our detriment, such as with a urinary tract infection. Some strains of bacteria are common to nosocomial infections, and identifying these bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the morphology and characteristics of each strain of bacteria help us to better understand the role of bacteria in the body as well as helps us understand how they can cause illness, and what treatment regimen to set in place. In lab this semester, a sample of unknown
1) What does the body use carbohydrates for? One of the main jobs of carbohydrates is to provide fuel for the body to do its job. So if we want to run or walk somewhere or play sports or even work -- all of those activities use carbohydrates. It is our main energy source and helps the body maintain energy.
Aim: To classify unknown substances according to their structure type and to observe how the structure of materials affects their uses.
An unknown was given to our group from the professor. The unknown was in nutrient broth, the group received unknown number 3. And the task was to identify the unknown and try to make an educated guess, and identify the unknown #3.
The guiding question of this ADI lab was, “What are the identities of the unknown compounds?” The goal of this lab was to understand the relationships between moles and molar mass to find the identity of unknown compounds. The mole can be used to measure small amounts of a substance or is used to convert from unit to unit using dimensional analysis. One mole is equivalent to the molar mass in grams of that substance. If you start with the moles of an unknown substance, multiply it by a given compound’s molar mass, and then divide it by however many moles are in the compound of your choice, you will get the mass of the compound. With that answer you can then compare with mass of the compound in the bag to determine its identity. We first started
Carbohydrates are the product that made up from carbon, hydrogen and oxygen. Carbohydrates are form by the combination of carbon dioxide and water molecules. The carbohydrates contain two specific functional group in it which is the hydroxyl groups and carbonyl groups.A reducing sugar is a type of sugar with is an aldehyde group.This means that sugar can act as a reducing agent.The procces of reducing sugar is isomerisation,example of reducing sugar islactose,maltose,glucose and fructose.All monosaccharides are capable of reducing other chemicals such as copper (II) sulphate to copper oxide.Beside that disaccharides such as maltose and lactose are reducing sugar,however sucrose is non reducing
Half of each tube’s contents are poured into a new test tube each respectively after the tubes are incubated for 1 hour. One set of tubes is tested for:
7.When water bath is ready, put each test tube into the water bath. Wait 5 minutes.