How to keep Chinese eggplant purple
There is a wonderful restaurant in Woburn, MA called Lanna Thai Diner; everyone should go there. When they serve curry with Chinese eggplant, the eggplant is soft and well-cooked, but still bright purple on the outside.
I can get the right kind of eggplant (Russo's in Watertown, MA -- another place everyone should go), but when I cook it, the skin turns an unappetizing brown.
I've tried stir-frying it hot. I've tried steaming it first. I asked the guy at Lanna Thai, but he told me it was a secret recipe; not sure if he was teasing or not, but I still don't have an answer.
I have a variety of things still to try: Salt? Lemon juice? Blanching in water with baking soda?
But I'm hoping some wise soul on these boards already knows the answer!
Thanks for any suggestions.
I've never once in my life seen a bright-purple cooked eggplant. But at the same time, I don't find brown skin unappetizing in the least. A good number of cooked foods are brown. Seems natural to me.
I'll be watching this tread keenly to see whether there's some "secret" I've never known I needed!
The "secret" is to blanch the eggplant in oil beforehand.
Heat oil to 350F in a wok, large pot or large skillet. Blanch eggplant in the oil for 2 minutes. This will maintain the purple hue of the eggplant. Transfer to a plate lined with paper towel and use the eggplant as called for in your recipe.
Deep fry is a common solution, especially in the restaurant. However, i just don't really like to soak up extra fat. Steam won't work either.
Another way to keep them purple is to press them in the boiling water. The problem of this method is you need to cook them one by one.
1. Cut the eggplant in the desired shape (don't do french cut because it is harder to handle in the boiling water) and put them in the cold water immediately.
2. Boil a small pot of water and keep the water boiled.
3. Now is the key. Pick up one piece of eggplant with fork and press it down in the boling water. You can actually do a little test yourself. Soon as you release the eggplant, you'll see the side under the boiling water remains purple, while the part exposed in the air (steam) turns brown very quick.
4. Make sure the eggplant is fully cooked (you can tell by using another fork to see if it has turn soft) before you removed them out of the boiling water. The whole key is because eggplant oxide easily.
As I said, the problem of this technique is about time... because I can only do one or maybe two piece at a time. I am still thinking how can I press a lot of eggplant pieces all at once in the boiling water...
Hope this helps.
Just thought I'd follow up on this, to leave a definitive trail for any who follow:
The problem is oxygen. Hot + oxygen = brown skinned eggplant.
Forcing them under water while cooking does maintain the purple hue. (You have to force them, because otherwise they float and are exposed to the air while cooking. I used a plate with a weight on it.) Unfortunately, boiled eggplant isn't very tasty; it's rubbery and has no flavor.
"Blanching" in oil, which is effectively deep-frying, but with slightly less heat, works great. They maintain a nice hue and the flesh comes out deliciously creamy. I floated them purple side down and didn't stir them a lot, but I'm not sure this was necessary.
Of course, you pay the price in absorbed fat, so this isn't a healthy cooking technique. Once again, fat = flavor. And In this case also color.
Thanks for everyone's help and suggestions.
I suspect what the restaurant does is to deep fry the eggplant to pre-cook, as ipsedixit mentioned.
Deep frying is a very common and quick way for restaurants to get the food out.
After a minute or two of deep frying, the eggplant is allowed to drain off excess oil oil. While the eggplant is draining, the rest of the dish is finished off in another wok. The eggplant is added at the last 30 seconds to finish off cooking and coat the eggplant pieces.