4.—(1) Where the letter “a” is shown in brackets after the “X”, only one of the two simulants specified will be used in the migration test, that is to say —
(a)if the pH value of the food is higher than 4.5, simulant A will be used;
(b)if the pH value of the foodstuff is 4.5 or less, simulant B will be used.
(2) Where the letter “b” is shown in brackets after the “X”, the indicated test will be carried out with ethanol 50% (v/v).