Kenneth Chang has an interesting guest post about salt on John Tierney’s blog:
… salt can remove bitterness without removing the bitter compounds.
Ms. [Shirley] Corriher described a demonstration given by Gary Beauchamp, director of the Monell Chemical Senses Center in Philadelphia. It’s an experiment you can try at home.
Get a bottle of tonic water. Take a taste. The bitterness is quinine, a compound derived from bark of the cinchona tree. There’s also a bit of sweetness from sugar or corn syrup added to offset the bitterness.
Add a bit of salt to the bottle. Take another taste. “It’s almost like sugar water,” Ms. Corriher said. “You taste a little quinine, but it’s just the change is amazing, how the salt suppresses bitterness.”
Surprisingly, salt suppresses bitterness better than sugar.
That is why some people sprinkle salt on grapefruit, cantaloupe and other fruit. (It’s apparently not known how salt suppresses the bitterness, whether the salt somehow disrupts the bitter receptors on the tongue or whether it’s some sort of post-processing by the brain.)
This reminded me of the article I linked to last week about “salt coffee” catching on in Taiwan:
A Taiwan coffee chain is enjoying sweet results after launching “salt coffee”, which produces a unique but not entirely salty taste.
Since launching salt coffee on Dec 11, the 85 Degree Bakery Cafe, Taiwan’s largest coffee chain, has changed coffee drinkers’ habits and customers are increasingly ordering it rather than black or sugared coffee.
“Public reaction surprised us. Nowadays an outlet in north Taiwan can sell 700 cups of salt coffee per day and a store in south Taiwan can sell 700 cups, which is 20 to 30 percent more than the daily sale of our brand coffee, American coffee,” Cathy Chung, spokeswoman for 85 Degree Bakery Cafe, says.
Chung says her company hit upon the idea of launching salt coffee because the trend of using sea-salt as a health ingredient in food or as cosmetics is sweeping Taiwan.
At first I dismissed this as a fad, but if salt is reducing the bitterness of the coffee that could explain its popularity. I tried it out by adding sea salt to a small sample of my morning coffee today, Stumptown’s Wondo Yirgacheffe. Adding just a little salt noticeably reduced the bitterness in the cup. Adding a bit more removed it completely. Salt works! The second pinch also made the liquid undrinkably salty.
Now I’m not actually recommending you try this. The Wondo is an excellent, gentle coffee, and it needs that background bitterness to support its more delicate flavors. Taking it away just makes it taste insipid. But you can’t always get good coffee. If you’re stuck drinking acrid brew at the airport at 5 am, then maybe this salt trick could come in handy.
Chang’s article about cooking with Shirley Corriher is also worth a read. I’m currently learning from her book Cookwise, which pairs recipes with scientific background about why they work the way they do. I started cooking in earnest recently and come to it very naive about technique, so this has been very useful for me regardless of whether I’m making her recipes (since my interests tend more toward Asian and Indian dishes I haven’t tried many of them). It makes a great resource along with McGee’s On Food and Cooking.