Lab Report for Food Test

Procedure- The procedure for this lab includes many simple steps and a few different things we are testing. Our first Procedure was to combine water and salt to see what kind of reaction it would make. First we fill the graduated cylinder with 100 ml of water. We then measured 1.0 grams of table salt on a balance to get an accurate amount. After, we took the measured amount of salt and poured it into the water filled beaker. Lastly, we watched and recorded the reaction.

The mixture was then transferred to a clean centrifuge tube via pipet, carefully not wetting the upper walls of the tube. Zinc granules were then added and the tube was immediately plugged with cotton 1/3 of the way into the tube. The tube was then warmed in a hot water bath for about 5 minutes, the folded red litmus paper was inserted at the top of the tube with a wet crease. After a few minutes, nitrate is indicated on the wet crease of the litmus paper, turning it blue. For the Carbonate test, 25 mg of carbonate sample was added to a centrifuge tube and 3 drops of 6 M H2SO4 was added. A disposable pipet was used to transfer a drop of Ba(OH)2, that hung directly from the pipet over the carbonate solution, and the observations of the drop were recorded.

In general, in the fermentation lab the more gas produced showed the level of fermentation, the food source that produced the most CO2 the fastest during the fermentation process was the sample of 0.2 M glucose at 37°C topping of at 9.2ml of CO2 produced in 40 minutes total (see Table 2). This sums up the most optimal conditions for cell fermentation was a simple monosaccharaide, glucose, and at temperature of around 37 C which is the temperature of the human body. The hypothesis was correct a simple sugar easily broken down and higher temperatures are optimal. These results showed that the simpler the sugar the better it is for breaking it down. Sucrose is a disaccharide and starch is a polysaccharide. The hardest to break down was starch. This is possible due to

Ans) the monosaccharides are called the reducing sugars this is because they contain the aldehyde group.in the experiment these are lactose, glucose, Dextrose, fructose, and maltose.

Digestion The food sample is digested by heating it in the presence of sulfuric acid (an oxidizing agent which digests the food), anhydrous sodium sulfate (to speed up the reaction by raising the boiling point), and a catalyst, in this case the Kjeldahl tablets, to speed up the reaction. This process converts any nitrogen in the food (other than in the form of nitrates or nitrites) into ammonia, and other organic matter to C02 and H20. Ammonia gas is not released in an acid solution because the ammonia is in the form of the ammonium ion (NH4+) which binds to the sulfate ion (SO42-) and thus remains in solution, which gives a greenish blue appearance: N (from flour) + H2SO4  (NH4)2SO4 + H2O

The second test that is being preformed is the Benedict’s test, this test if for reducing sugars in the solutions. A carbohydrate that has a free aldehyde(carbon double bonded to an oxygen, a hydrogen attached as well as a one open R group) functional group as part of its molecular structure is know as a reducing sugar.(Simon et al, 2015) In the

Script Introduction: The digestive system is needed in order to break down food in order to be able to use the food as energy, and my group and I have simulated the digestive process of a muffin. Mouth: In the mouth, mastication in the form of chewing takes place, which is a type of mechanical digestion. Mastication occurs when the teeth, with the incisors simulated by the knife and the molars simulated by the motor and pestle, cut the food into smaller particles, which maximised surface area. This allows the amylase enzymes in the saliva that are secreted from the salivary glands to more rapidly distribute and break down the starches in the ball of chewed muffin.

An enzyme solution was prepared by mixing one mL saliva with nine mL distilled water andthirty mL 0.5% sodium chloride. Two mL of the enzyme solution was put in a large test tube andlabeled as 4°C. Two mL of the buffered starch solution (1% stach in phosphate buffer pH 6.7)was added in a separate large test tube. Both the test tubes were incubated for ten minutes inan ice bath (4°C). The solutions were immediately mixed. Three drops of the mixture was takenquickly and two drops of the 0.001 M iodine solution was added simultaneously onto a spotplate (first well). This was the zero minute. After one minute interval (incubation continued),three drops of the mixture was taken again and two drops of the iodine solution was addedsimultaneously

Glucose which is a sugar gave a positive result. Starch is founded in plants therefore gave a negative result. Unknown which didn’t contain sugar gave a negative result. Distilled water which is the one used as a control gave a negative result. Onion Juice which contain monosaccharides and polysaccharides gave a positive result. Potato juice which has little sugars gave a positive result.

A 100mL volumetric flask was used to create diluted solutions. The first dilution was composed of 4.837g of Fe(NO3)3 and the rest deionized water. After the first sample was created, it was poured in a beaker and set aside while the flask was being rinsed out to make sure none of the solutions were contaminated. The second dilution was composed of 0.0194g of KSCN and the rest of the volumetric flask was filled to the line with deionized water. After the second sample was created it was poured in a beaker and set aside while the flask was being rinsed out. Lastly, 50mL of HNO3, was added to the 100mL volumetric flask and the rest of the flask was filled to the line with deionized water. After the last solution was

Carbohydrates are organic compounds that consist of carbon, oxygen, and hydrogen. There are four different ways that carbohydrates can be classified: monosaccharides, oligosaccharides, and polysaccharides. Monosaccharides are the simplest sugars. They are aliphatic aldehydes or ketones and most have five or six carbon atoms. Oligosaccharides are two monosaccharides linked together by the elimination of a water molecule which allows the glycosidic bond can form. Polysaccharides contain more than one glycosidic bond and are the heaviest and most prominent natural forms of carbohydrates (Mcclemmon). Carbohydrates also have the potential to be reducing sugars. This means they have a free aldehyde or ketone group that is capable of acting as a reducing agent. All monosaccharides are reducing sugars and the other forms have the potential to be one. There are several different ways to identify the bonding of a carbohydrate in the lab. In this lab, combinations of several different tests were used in order to determine which functional groups were present. Benedict’s and Barfoed’s tests both test for the presence of a reducing sugar. Benedict’s reagent produces a red precipitate when heated in a the presence of a reducing sugar. Barfoed’s reagent tests for reducing sugar as well, but does not test for it in disaccharides, so this test is used to distinguish between monosaccharides and disaccharides. Disaccharides are not oxidized

Put three drops of hydrogen peroxide (3 %) on it (after dabbing dry with paper towel) to observe the effect of pH on reaction activity

12. The crocodile clips are attached to the copper electrodes of the experimental apparatus and the power supply is turned on. Simultaneously, the stopclock is started. The thermometer is checked every 30s. 13. After 300s the stopclock is stopped and the power supply is turned off. The negative cathode is carefully removed and is dried using a hair dryer. 14. When dry the negative cathode is placed on the electronic milligram balance and its final mass is recorded. 15. The positive anode and negative anode of the experimental apparatus are disposed and the electrolyte is poured out to ensure that the anode slime (impurities) does not contaminate the solution. 16. The electrodes of the experimental apparatus are replaced with new copper strips. 17. Steps 7 to 16 are repeated. However, this time, the rheostat is adjusted using the calibration apparatus until the multimeter shows approximate readings of 0.40 A, 0.60 A, 0.80 A and 1.00 A respectively. 18. Time permitting, the entire experiment is repeated. Safety Copper sulphate may cause irritation and burns if it comes into contact with the eyes. As standard lab procedure, safety goggles and lab coats must be worn at all times. Control of Variables Volume of Electrolyte Used

Carbohydrates are molecules containing the elements carbon, hydrogen, and oxygen in a 1:2:1 ratio. Glucose (C6H12O6) is an example of a carbohydrate; also known as a simple sugar. Simple sugars or monosaccharides make up carbohydrates as its subunits. Some subunits or simple sugars combine with one another to form disaccharides (two simple sugars bonded) and polysaccharides (three or more simple sugars bonded) via dehydration synthesis. Many simple sugars (monosaccharides) are reducing sugars which means they contain free aldehyde (-CHO) or ketone (-C=O) groups and when they interact with oxidizing agents such as copper, they reduce them. Benedict’s reagent contains copper in the form cupric ion complexed with citrate in alkaline solution. When reducing sugars are presented with Benedict’s reaction, they will reduce the cupric ions (Cu²⁺) into cuprous oxide (Cu+), which is reddish orange. By testing solutions with Benedict’s reagent, we will be able to determine the reducing sugars based on their ability to produce cuprous oxide with a reddish orange product. It is expected that the positive control; reducing-sugar solution, and glucose will reduce the reagent and turn reddish orange while the negative control; distilled water, and sucrose will produce a negative result of either light blue or no color change.

(d) Dissolve all of solid KA 2 in distilled water and filter. Use separate portions of the filtrate for tests (i) to (v). (i) Add aqueous NaOH, then in excess, and warm.