“Contrary to conventional wisdom boiling vegetables in salted water isn’t about seasoning them nor is it about making the water boil faster, sooner or more vigorously.”
Have you ever steamed vegetables? For years we’ve been told steaming was healthier than boiling – right? Did you ever notice after steaming broccoli, for an example, all that green water in the bottom of the pot or microwave container when you remove the veggies? Why is it green? The green color is from the chlorophyll (remember botany?) that is water soluble – so the steam hits the veggies and as it heats the broccoli it also causes the water inside the veggie to heat up and to leak out – simple science. The chlorophyll comes along with the leakage. Guess what else leaks out? Many of the nutrients because they too are water soluble.
BUT consider this technique instead: Plunging fresh vegetables into boiling salted water (also called par-boiling or blanching.)
This plunge technique places the veggies smack dab in the midst of a science experiment known as reverse-osmosis. The boiling salted water is a different saturation or density than water inside the vegetables and science tells us all the water in the pot – both salted and inside the broccoli – wants to “equalize.” Normally the water inside the veggies would be drawn to the salted water by a process called osmosis…but by heating the salted water to boiling it changes the pressure – the boiling water being higher in pressure – which reverses that process and the hot salty water wants to get into the veggies. BUT if the veggies are already pretty hydrated – they are fresh, right? – there isn’t any room. Some of the salty water does get in, but not much. Meanwhile the veggies heat up and in a short time they cook just enough to enjoy “al dene” but the water soluble stuff, the chlorophyll and nutrients in the veggies remains inside. Remove the heated veggies from the water, rinse under cold or hot tap water and most of the salt on the surface is removed. You end up with al dente vegetables retaining more color and nutrients.
Translation: A quick boil or “blanch” in salted water will not leach water soluble nutrients from the vegetables and very little salt actually gets into the vegetables – ergo it is actually a much healthier way to prepare vegetables. Based on my experiences with steamed vegetables and all that green water – and after trying this method and being pleased with the results – I recommend you prepare veggies by quickly par-boiling them in lightly salted boiling water.
How about that! ~CB