The fizz is usually carbon dioxide. When water reaches an effervescent tablet, ingredients such as an acid and a bicarbonate can react. The escaping gas forms bubbles and helps the tablet break apart so its contents disperse in the water. IUPAC’s effervescent tablet definition
What the glass can tell you
If you prepare two products in clear glasses, you might see one bubble vigorously and the other fizz more gently. Look at the two labels and you may find different serving sizes or preparation instructions. The amount and appearance of the bubbles give you a view of the preparation. For the actual amount of a vitamin or mineral, read the declared quantity per serving.
| Question | Where to look |
|---|---|
| Why are there bubbles? | The tablet’s acid and bicarbonate reaction in water |
| How much of a nutrient is in it? | The nutrition panel and its serving basis |
| How long should I wait before drinking? | The preparation directions for this pack |
| What changed when a tube was left open? | The condition of the tablets and storage instructions |
Why the cap matters
Moisture can reach the dry ingredients before you intend to make the drink. That is one reason effervescent formulations often come in a moisture-resistant pack. If a tube becomes damp or tablets stick together, check the storage directions and ask the manufacturer about the affected pack. WHO tablet monograph
For the practical steps, see the first-glass preparation checklist. For shopping, the effervescent supplement guide explains how to compare the declared serving and format.