Carbohydrates: Monosaccharides and Disaccharides

AS1  COURSE 4010[pic 1][pic 2]

FOOD & NUTRITION BASICS

LABORATORY REPORT[pic 3]

LAB 1   CARBOHYDRATES

Year  2018__         Sem 1  

DUE DATE  Next FNB practical

NAME (CAPITALS) WONG TSZ YING                         GROUP LETTER    D          

This work is the product of my own efforts and has not been copied from any other sources except where full acknowledgement has been given.

SIGNED________________________________________ Student No._20082222_

Carbohydrates: Monosaccharides and Disaccharides

Introduction

Carbohydrate are essential to food (human diet) as energy source. Not only for energy, but also can have other function like taste and texture. This report discusses five experiment to study the properties of carbohydrate including physical, functional and sensual.

Experiment 1:  Relative solubility of Carbohydrate, Glucose and Galactose.

Result and discussion

Table 1 - Data from experiment

Solubility is a result of an interaction between polar water molecules and the ions which make up a crystal.^[1] Carbohydrate can dissolved with water because it have the hydroxyl group which are charge. Water have hydrogen bond and it also have negative and positive electrical charge, which can attract carbohydrate and will then destroy the structure of it. And it caused dissolved.

Compare to the published values, it have a quite difference results. Since it have some error or limitation may made, like solution flow out by accident.

Conclusion

Referring to table 1, glucose was more soluble than galactose since glucose was dissolved with 6.09 grams and galactose was dissolved with 2.35 grams, which is mean that the mass of glucose can dissolved more than galactose in water. Also the graph shows that the saturation point of glucose are higher than galactose. Although these two are both monosaccharides and similar molecular structure, they are different solubility. And this can be linked to hydrogen bond with water molecule. For these sugar use of human, solubility in water of glucose molecules allow them to pass through the cell membrane into cell. Therefore, it can be transport in the blood and provide energy to us. What’s more, since the solubility of it, it can also affect the water potential of human system.

Experiment 2 and 3 : Relative sweetness and salt taste threshold

Result and discussion

Table 2 - data from experiment

According to the graph, our group member both sweetness and salt tastes are close to each other. In sucrose both threshold are number 4 bottle, also glucose, maltose and salt threshold are similar (between 7-8, 8-10 and 1-2).

Compare to sugar and salt thresholds, we can taste the salt when concentration is lower, but sugar is higher required. Our sensitivity to each of the fundamental tastes is related to how much of them we do (or don't) need. We need a lot of sugar, and so we're the least sensitive to it; we're about 10 times more sensitive to salt than sugar, causing us to consume less of it. ^[2] Also, our mouth have sodium chloride receptor which use to taste salty but sweetness are more variant .That is why we can taste salty more easily.

Experiment 4: Measuring sugar concentration

Result and discussion

Table 3 - data form experiment

“%Brix” - Degrees Brix is the sugar content of an aqueous solution. One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by mass.^[3] Therefore the statistics of measurements (refractive index) can shows the level of sweetness which means sugar concentration.