Experiment about efficiency of bisulphite as wine preservative

[herich]

Homework Statement

Could you suggest an experiment to determine the efficiency of sodium hydrogensulphate(IV) as a wine preservative?

2. The attempt at a solution
I just think that since wine contains ethanol, which would be oxidized in air to form ethanoic acid slowly, by comparing the pH value of the wine between a sample exposed to air and a control can the efficiency be determined.

But how can I CALCULATE the efficiency? or are there other better and more convenient ways?

 

[nate808]

One possible experiment to determine the efficiency of sodium hydrogensulphate(IV) as a wine preservative is to set up a controlled experiment with two groups of wine samples. One group would have the sodium hydrogensulphate(IV) added as a preservative, while the other group would not have any preservative added.

The samples can be stored at the same temperature and conditions for a certain period of time, and then the pH values of each sample can be measured. The group with the preservative added should have a lower pH value, indicating that the preservative was effective in preventing the oxidation of ethanol.

To calculate the efficiency, you can compare the initial pH value of the wine before adding the preservative to the final pH value after the storage period. The percentage of change in pH can then be used to determine the efficiency of the preservative. For example, if the initial pH was 4 and the final pH was 3, the efficiency would be calculated as (4-3)/4 * 100 = 25%.

Other factors that can affect the efficiency of the preservative, such as the concentration of the preservative and the storage conditions, should also be taken into account in the experiment. This experiment can be repeated multiple times to ensure accuracy and to determine an average efficiency value.

 

[Blueshift5]

Thank you for your question. I would suggest the following experiment to determine the efficiency of bisulphite as a wine preservative:

1. Prepare two identical samples of wine, one with bisulphite added and one without (control).
2. Label the samples accordingly and store them in identical conditions.
3. Measure the initial pH of both samples using a pH meter.
4. Allow both samples to sit for a predetermined amount of time (e.g. one week).
5. After the predetermined time has passed, measure the pH of both samples again.
6. Compare the change in pH between the sample with bisulphite and the control sample.
7. The sample with bisulphite should have a lower change in pH, indicating that the bisulphite was able to preserve the wine better.
8. To calculate the efficiency, you could use the following formula: Efficiency = (pH change in control sample - pH change in sample with bisulphite) / pH change in control sample x 100%.

Alternatively, you could also measure the amount of ethanol remaining in both samples after the predetermined time and compare the difference. The sample with bisulphite should have a lower decrease in ethanol content, indicating better preservation.

I hope this helps. Please let me know if you have any further questions or if you would like to explore other methods for determining the efficiency of bisulphite as a wine preservative.