Litmus test (politics) Litmus test (politics) A litmus test is a question asked of a potential candidate for high office, the answer to which would determine whether the nominating official would proceed with the appointment or nomination. The expression is a metaphor based on the litmus test in chemistry, in which one is able to test the general acidity of a substance, but not its exact pH. Those who must approve a nominee, such as a justice of the Supreme Court of the United States, may also be said to apply a litmus test to determine whether the nominee will receive their vote.
Olive oil acidity by the European Commission regulation No. 2568/91) is a manual titration procedure: a known volume of the oil to be tested is added to a mix of ether, methanol and phenolphthalein, known volumes of potassium hydroxide KOH 0.1M (the titrant) are added until there is a change in the color of the solution. The total volume of added titrant is then used to estimate the free acidity. The official technique for acidity measure in olive oil is accurate and reliable, but is essentially a laboratory method that must be carried out by trained personnel (mainly because of the toxic compounds