Study the effect of different temperatures 3 different Ph on the activity of Salivary Amylase on Starch


Salivary glands produce salivary amylase, an enzyme. Each individual action of any salivary amylase is effective on different available starch. Changes in the temperature directly impact the nature of salivary amylase. At the time of digesting, all the food particles are digested and this helps in generating energy from food. The main reason for executing this experiment is to understand the impacts of different pH and temperatures on salivary amylase.

What is Salivary Amylase?

Figure 1: Salivary amylase

Another important term, associated with salivary amylase is ptyalin. Overall, oral perception of all kinds of starches is affected by salivary amylase and it is said to work on starch metabolism pre-absorptively. In relation to any ingested starch, the enzyme influences associated plasma glucose levels.

Aim of the Experiment

The main aim of this experiment is to study and understand the effects of variations in pH levels and temperature on each significant activity of salivary amylase on any starch.

Required Materials

In performing the experiment, some materials are required and these are as follows.

  • Droppers

  • Test tubes

  • Water

  • Ice cubes

  • pH tablets

  • Iodine solution

  • Saliva solution

  • Droppers

  • Thermometer

  • Three separate test tubes with iodine

  • Beaker with water

  • Starch solution with NaCl

  • Wire gauze

  • Bunsen burner

The Process to Experiment with pH Effects

In this specific experiment, a proper starch solution is to be made. In this preparation, distilled water is to be taken in a bottle of 100 ml. In this portion of water, the starch of 10 gm is to be mixed. All this starch is to be mixed properly and the solution is made. In the saliva of every living organism, salivary amylase is present. In understanding the effects of this experiment, a verified starch in an iodine solution can be the most effective one.

  • Approximately 1% of the starch solution with 3ml of NaCl solution is to be taken in a beaker.

  • This is to be divided into three equal portions and placed in three test tubes.

  • Different pH tablets are to be used at that time in marking each individual impact of the enzymes.

  • In the first test tube, a 5-pH tablet, in the second test tube, a 6.8 pH tablet, and in the third test tube, an 8-pH tablet is to be put. The temperature is measured to be set to 37-degree Celsius.

  • In every tube, a little portion of saliva is to be put after that and the reaction is recorded.

  • Changes in the solution’s colour can be noted.

  • The iodine drop is to be mixed for the second time and the next changes in colour are to be followed.

The Process to Experiment with Temperature Effects

The starch solution with each individual iodine and amylase is to be regarded as important to experiment with the changes in salivary amylase at different temperatures. All three test tubes are to be left under the cap in measuring each different change.

  • A solution with 15 ml starch and 3 ml NaCl is required for this.

  • In a beaker, a few ice cubes are to be put and the temperature is to be ensured at 50C.

  • In this beaker, tube A is to be transferred.

  • Two other beakers are taken and filled with water. These two beakers are heated up to 370C and 500C. These two temperatures are to be constant.

  • Tube B is transferred to that particular beaker with 370C and tube C is placed in the other beaker.

  • In all these three test tubes, 1 ml of saliva is mixed.

  • A little portion of solution from all these three tubes is to be taken.

  • After a certain interval, this solution is poured with a little dropper and the changes of colour at each step are to be followed.


The experiment of identifying changes in pH levels is important as each significant function of salivary amylase can be detected by this experiment. Different pH levels are the reason behind all changes in colour. The range of pH levels is effective and the most suitable pH level is considered to be 6.8. This is not of a high acidic range and therefore provides an average reaction rate. At this specific range, the starch is found to be easily digested in the stomach.

The test tube, which was set at 50°C, is found to reach an achromic point. At this high temperature, all enzymes are denatured. At a low temperature, the enzymes are deactivated. A longer time is required for starch in digesting at any temperature other than 370C.


In digesting food, an existing enzyme in the saliva plays the most important role which is known to be salivary amylase. This saliva is helpful for the starch as it digests disaccharides significantly. In performing a complete digestion process, pancreatic amylase helps the most. Both the temperature and the pH level are effective in relation to creating change within any digestion process. Changes in the colour of the solution during the experiment indicate the completion of the whole digestion procedure.


Q1. What is the optimum temperature for executing an experiment in salivary amylase?

Ans. 37 degrees Celsius is the most appropriate and optimum temperature. In executing the experiment with efficiency and with the most beneficial outcomes, this temperature can be regarded as the most suitable one.

Q2. What is the reason behind the segregation of an enzyme?

Ans. At a certain time, an enzyme is often found to segregate at a high temperature. The main reason behind such an action is that all enzymes are a significant kind of protein.

Q3. What is indicated by the transformation of the solution into an orange colour?

Ans. In understanding the nature of any experimental solution, the transformation of colour is to be followed properly. In an experiment, a pale yellow and orange coloured solution indicates that the whole digestion of the included starch is completed.

Updated on: 24-Apr-2023


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