Why poaching stays below a simmer
A poach holds the liquid at about 70 to 80°C (160 to 175°F). You'll see steam and the odd tiny bubble, but no real bubbling. At that heat, egg and fish proteins tighten slowly, so they set tender instead of squeezing out their water.
Vinegar helps egg whites set
Acid helps egg white proteins link up faster, so the white stays wrapped around the yolk instead of trailing through the water. Fresh eggs help too, because their whites are thick. Older eggs have thin whites that spread out.
Test yourself
Questions from the interactive lesson, with the answer and the why.
You look at a pot of water set up for poaching. Which description fits?
Gentle steam and a few tiny bubbles. Barely moving liquid keeps heat low enough to set proteins gently.
True or false: A poaching liquid should barely move, with steam rising and only a few tiny bubbles.
True. That gentle heat sets egg and fish proteins slowly, so they stay tender.
What went wrong? You poach salmon in water at a hard boil. The fish turns dry and chalky.
The heat was high and tightened the protein. Hard heat squeezes moisture out of fish protein.
Fill the blank: Fish poached in barely moving liquid stays moist because its proteins tighten ___.
Fish poached in barely moving liquid stays moist because its proteins tighten gradually. Slow tightening pushes out less water, so the fish stays moist.
How hot should poaching water be?
About 75 C. About 70 to 80°C (160 to 175°F) is steaming but not bubbling.
Why does fish poached in barely moving water hold more moisture than fish boiled hard?
Slow tightening squeezes out less water. Gentle heat lets proteins set without wringing out moisture.
