Sumac and za'atar: sour without liquid

Sumac is dried, ground berries from a shrub, deep red and tart from the fruit acids. It sours food without adding liquid, so it won't thin a dip or soften a crisp edge. Think of it as lemon juice in powder form.
What is in za'atar
Za'atar blends dried thyme-type herbs (wild thyme, oregano or marjoram, depending on the cook) with sumac, toasted sesame and salt. The herbs bring green fragrance, sumac brings tartness, and sesame brings nutty richness. It's often stirred into olive oil.
Test yourself
Questions from the interactive lesson, with the answer and the why.
You want a tangy hit on grilled onions that are already crisp at the edges. Why reach for sumac instead of lemon juice?
It sours them without adding liquid that would soften the edges. Juice wets the surface and softens crisp edges, while sumac is a dry powder.
True or false: Sumac is a chile powder that gets its heat from capsaicin.
False. Sumac is a tart berry powder, and its red color comes from the berries, not from chiles.
Fill the blank: Sesame seeds are toasted so heat browns them and builds a ___ aroma.
Sesame seeds are toasted so heat browns them and builds a nutty aroma. Browning creates nutty aroma compounds in the seeds.
What went wrong? You sprinkle dry za'atar over flatbread dough and bake it. Most of the blend slides off when you lift the bread.
The blend had no oil to bind it to the dough. Oil makes a paste that clings, and it carries the aroma of the herbs.
Your hummus is the right thickness but needs more tang. What is the best fix?
Sprinkle in sumac and taste. Dry sumac adds tartness without thinning the hummus.
