When I make tzatziki, sometimes I drain the cucumbers and sometimes I don’t. Conventional wisdom says you should, but in my experience it doesn’t always make a noticeable difference. I suspected that removing the seeds might reduce the cucumber’s water content, and I also wondered whether grating releases more liquid than dicing — which could be why many recipes insist on draining.
Last week I decided to test this while making a double batch for a party. Using two cucumbers, peeled and halved, I prepared four portions in different ways: seeded and diced, diced with seeds, seeded and grated, and grated with seeds. I weighed each portion, sprinkled 1/4 teaspoon of salt on them, and left them to drain overnight. The next morning I measured the liquid each one had released and reweighed the drained portions to normalize for slight differences in the starting amounts. The results are shown in the table below.
| Type of Prep | Undrained Weight | Drained Weight | Percent of Weight Lost |
| Seeded, Diced | 79 g | 64 g | 19% |
| Diced with Seeds | 98 g | 88 g | 10% |
| Seeded, Grated | 92 g | 66 g | 28% |
| Grated with Seeds | 91 g | 64 g | 30% |
The data from this small trial doesn’t definitively prove whether seeding consistently reduces water loss — the seeded and unseeded results aren’t uniformly different. However, it is clear that grated cucumber releases noticeably more liquid than diced cucumber. My partner, Zoe, dislikes grated cucumber in tzatziki because it can disappear into the yogurt, but for this experiment I grated some anyway to test the water release.
Putting the cucumber results in perspective: the goal of draining is to create a rich, creamy tzatziki rather than a watery one. Even after an overnight drain, each grated half-cucumber released only about a tablespoon of liquid, and each diced half released even less. In total the cucumbers yielded less than 1/4 cup of liquid. By contrast, draining the yogurt produced almost 3 cups of liquid overnight — a far larger contribution to overall moisture.
Conclusion:
Draining the yogurt is essential for creamy tzatziki. Draining the cucumber matters far less, though if you prefer to grate your cucumber it’s worth draining it as well to reduce extra liquid. Focus on using properly drained yogurt first, and treat cucumber draining as a secondary step depending on your chosen preparation (grated versus diced) and how dry you want the final sauce to be.
Learn how to drain yogurt if you haven’t already — proper yogurt drainage will have the biggest impact on texture and creaminess.