UNIVERSITI TUNKU ABDUL RAHMAN
UNIT DESCRIPTION : Food Chemistry
NAME : Yong Zhi Rhen
ID : 1307297
YEAR & SEMESTER : YEAR 3 SEMESTER 2
PARTNER’S NAME : Tan Kai Jie, Bernard Hiew, Leng Li Zhou
Practical group : P1
EXPERIMENT NO. : 3
EXPERIMENT TITLE: Measurement of Extent of Nonenzymatic Browning
DATE : 15/1/2016
LECTURER : Dr. Khoo Kong Soo
Experiment 3
Title:
Measurement of Extent of Nonenzymatic Browning
Objectives:
1. To understand the Maillard reaction.
2. To use simple model system to study factors that affect the rate of the Maillard reaction
Introduction: Browning is the process of becoming brown which normally referring to food. Browning has an important economic cost, causing deterioration of the value of product in the market of food. There are two type of browning reaction, one is enzyme-catalyzed and another one is non-enzymatic. Enzymatic browning is a chemical process, involving polyphenol oxidase, catechol oxidase, and other enzymes that create melanins and benzoquinone from natural phenols, resulting in a brown color.
Non-enzymatic browning is a chemical process that produces a brown color in foods without the activity of enzymes. The two main forms of non-enzymatic browning are caramelization and the Maillard reaction. Maillard reaction is a reaction between reducing sugars and amine resulting in browning and flavor development. Low
Introduction: Enzymes are needed for survival in any living system and they control cellular reactions. Enzymes speed up chemical reactions by lowering the energy needed for molecules to begin reacting with each other. They do this by forming an enzyme-substrate complex that reduces energy that is required for a specific reaction to occur. Enzymes determine their functions by their shape and structure. Enzymes are made of amino acids, it 's made of anywhere from a hundred to a million amino acids, each they are bonded to other chemical bonds.
There are few vegetables and fruits that turns to the color brown if their surface is exposed to oxygen. Once the veggies or fruits been exposed to oxygen, then the browning begins to appear, and electrons and hydrogen will be removed. This happens because of an enzyme called catechol oxidase. The enzyme will act on its substrate catechol to form a yellow compound which then reacts with the oxygen in the air and change into benzoquinone. The more concentration of the enzyme, the more browning appears.
Exploration Title: Effect of Temperature on rate of Osmosis Submitted By: Abdulkarim Kamal Date Submitted: October 19th 2015 Subject: Biology HL Teacher: Mr. Nick Aim: This is an investigation to determine the relation between temperature of a solution (sucrose) and the rate of osmosis Scientific Context: Osmosis is defined a passive transport process in which a fluid diffuses across a semi-permeable membrane, from an area of high solute concentration to an area of low solute concentration and vice-versa. There are various factors that could potentially influence the rate of osmosis; these factors include volume, concentration, and temperature. If all external factors that may interfere with rate of osmosis are controlled, the results will show equal amounts of fluid on both sides of the barrier (membrane); this is known as an “isotonic” state.
The topic of research is, “how fast does an Alka-Seltzer tablet make gas?”. In the experiment, the scientists will be measuring the chemical reaction rates that occur, when 1 Alka-Seltzer tablet is placed in a specific temperature of water. The independent variable during the experiment will be the temperature of the water (degrees Celsius). The dependent variable during the experiment will be, the rate in which gas is produced (in seconds). The constants of the experiment, will be the amount of water used and the Alka Selter compound.
Dependent Variable amount of product (glucose and fructose) produced 2. Independent Variable temperature 3. Controlled Variables pH, amount of substrate (sucrose) present, sucrase + sucrose incubation time Effect of Substrate Concentration on Enzyme Activity 1. Dependent Variable amount of product (glucose and fructose) produced 2.
1% glucose, 1% maltose and 1% lactose all progressively get positive results by changing colours to reddish brown at the end of this experiment. In this case the aldehyde functional group that is present in the products (monosaccharides and some disaccharides) in this reaction is able to reduce copper in the presence of alkali and this produces colour changes while converting to an aldose sugar. Honey is made of fructose and glucose which instantly turned brown after the test-tube was placed in the boiling water because of its active aldehyde and carbonyl group. The copper (II) sulphate present in the Benedict’s solution reacts with electrons from the aldehyde group which results in a redox reaction to from cuprous oxide, a red brown precipitate that seen in all of the above mentioned solutions (Hill, 1982). Beer also gave positive results because it contains aldehydes and ketones (i.e. acetone, trans-2-butenal, furfual) during its beer production process where the sugars are converted through fermentation (Hill, 1982).
55 degrees celcius Table 6: Effect of Sucrose Concentration on Sucrase Activity Optical Density 35 g/L 30 g/L 25 g/L 20 g/L 15 g/L 10 g/L 5 g/L 0 g/L 1 1.007 0.974 0.950 0.926 0.849 0.734 0.515 0.003 2 1.002 1.011 0.947 0.937 0.834 0.766 0.496 0.002 3 0.980 0.998 0.944 0.932 0.838 0.754 0.495 0.001 average 0.996 0.994 0.947 0.932 0.840 0.751 0.502 0.002 Effect of Sucrose Concentration on Sucrase Activity 5. State how sucrase activity changes with increasing sucrose concentration. First sucrase activity increases greatly. After 10 g/l sucrase activity continues to increase but at a slow rate until it reaches 30 g/l. At 30 g/l to 35 g/l sucrase activities mostly stayed the same
1.1 Abstract The purpose of quantitative analysis of protein using a spectrophotometer is to measure the concentration of proteins in a given sample. The experiment is conducted by laboratory method (Biuret Test) and using spectrophotometer to analyze the absorbance of reactants at 540 nm, hence determining the concentration of the proteins in a given sample. The purpose of stopped enzyme assay to study B-galactosidase is to determine the effect of temperature and concentrations of substrate on enzyme activity.
Abstract – Methyl trans-cinnamate is an ester that contributes to the aroma of strawberry. It can be synthesized by an acid-catalyzed Fischer esterification of a methanol and trans-cinnamic acid under reflux. The solution was extracted to obtain the organic product, and evaporated residual solvent The yield was 68%, but there is some conflicting data regarding the purity. The melting point, IR, GC-MS indicate a highly pure desired product whereas 1H NMR shows there are unreacted reagents still present.
Typical applications pertain to the quantitative and/or qualitative analysis of food composition, natural products, food additives, flavor and aroma components, a variety of transformation products, and contaminants, such as pesticides, fumigants, environmental pollutants, natural toxins, veterinary drugs, and packaging materials. And particular food applications involving GC, such as carbohydrates and amino acids. Lipids and accompanying lipophilic compounds. flavors and aroma. GC can be used for the direct separation and analysis of gaseous samples, liquid solutions, and volatile solids.
What is the effect of temperatures 10°C , 20°C, 40°C, 60°C and 70°C ± 1/°C on yeast fermentation when baking bread? ii. Aim: The focal aim of this experiment is to investigate the effect that temperature has on the growth and respiration of yeast (Saccharomyces cerevisiae) fermentation. iii.
Dependent The time taken for the bluish -black color to fade away (color of Iodine solution mix with starch solution ). The rate of enzyme reaction Minutes (min) Table 1.1 – Table shows the controlled variables in the experiment variables Units Measures of controlled variables.
- It is hydrolysis because it breaks down the polypeptides and involves the insertion of a water molecule. 10. Why were the results of the canned (cooked) pineapple different than the results of the fresh, raw pineapple? - Because most of the canned pineapples’ bromelain was destroyed in the canning process while the fresh pineapple still contains bromelain causing the reactions to be different. 11.
Joshua Miller 12/18/17 Fermentation Lab report Introduction The term fermentation refers to the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat (wikipedia). Sugars are converted to ethyl alcohol when fermentation happens. In this experiment we determined if yeast cells undergo fermentation when placed in a closed flask with no oxygen. Glucose and yeast are mixed together in a closed flask and allowed to incubate for about one hour.
This experiment aims to separate the components of the green colored food dye and get the TLC profile of each eluent collected. III. Experimental Procedure Before starting with the column chromatography for food dye, the right solvent must be chosen between 2-butanol with acetic acid, ammonia in butanol, 1 part 1-butanol 1 part acetic acid, and 2 parts methanol 1 part water. In choosing the appropriate solvent for column chromatography, the solvent system must give a TLC profile wherein most of the spots are well separated and has a Rf value within 0.3-0.5.