IMG 103/3: FOOD CHEMISTRY
LABORATORY REPORT
TITLE : MEASURING pH LEVELS AND WATER
ACTIVITY OF FOODS
NAME:
MATRIC NO:
GROUP: 2
DATE OF EXPERIMENTAL WORK: 13 MARCH 2013
DATE OF SUBMISSION: 20 MARCH 2013
TITLE: MEASURING pH LEVELS AND WATER ACTIVITY OF FOODS
ACTIVITY 1
Introduction :
This experiment was performed to investigate the pH levels of different types of food products. The pH of a solution can be determined experimentally in several ways. The pH scale is the range of pH values from 0 to 14. The paper that indicates the complete range of pH value from 0 to 14 is called the universal indicator. pH paper is a strip of filter paper that is soaked in universal indicator and then dried. An electronic pH meter is used for more precise measurements. A pH meter determines pH from the electrical potential between two electrodes in a solution. The potential varies with pH and activates an analog or digital meter calibrated to read pH directly to the nearest 0.01 or 0.001 unit. pH value is used to measure the solution acidity and alkalinity based on its concentration of hydrogen ion. An ion is an atom or molecule that has gained or lost of electron, and thus has a negative or positive charge. The pH scales measures the concentration of those charges, assigning them a value from 0 to 14.Pure water at room temperature (77 Fahrenheit), for example has a pH of 7.0 and is considered as a neutral. Water with a pH below 7 is defined as an acid and above 7 is an alkaline. So a pH measurement of 0 represents the strongest acid, and a pH value of 14 represents the strongest alkaline. pH levels is very important in food industry as some of the microorganisms can live within a certain range of pH.
Objectives : * To recognize the pH value of most of the household products using universal paper and calibrated pH meter * To be able to classify the household food products according to their range of pH values
Materials :