Thank you for a terrific class!

Good one and welcome back. You were missed.

Nice lesson. And very useful now that summer approaches! Don't forget your suntan lotion everyone, we don't want any unwanted Enzymatic browning;p

Thank you for the great lesson. Rouxbe is great as always!!

I do, however, have a question. Often, I roast my cauliflower with olive/canola/safflower oil and what ever herb I am inclined to that particular day. If I were to add an acid (say in a spray bottle to disperse it evenly) in order to keep the cauliflower white(r) when roasting would this work? Is it even desirable? I happen to love the roasted flavor, but sometimes the color is unappealing. I want the brown roasted part, but on a whiter background. Gosh, one would think I was referring to a painting. There is some thing wrong with us foodies. Seriously. And in keeping with Iain G, you put suntan lotion on your face, arms, etc. DON'T FORGET THE TOPS OF YOUR FEET! A friend developed skin cancer in that location recently, who knew?

I like to steam cauliflower and other vegetables. If steaming a veggie that benefits from an acid cooking environment, should the acid be in the steaming water or applied to the vegetable?

We will cover other cooking methods for veggies, such as steaming, roasting and braising down the road, even sous vide hopefully.

Unless cooking the vegetable in a liquid medium, adding acids topically during the cooking won't really benefit. Adding an acid to the steaming water won't benefit the pigment that much. Roasting will alter some pigments, but not as dramatically as simmering, and create desired caramelization.

So if not simmering or blanching, don't go out of the way to put an acid on your food, unless you want that flavour there.

Thank you very much, this lesson is really helpful.

I suspected an acid spray would not really help after a little investigation in my various cookbooks and on the Net, but KNEW I'd receive an informed reply here at Rouxbe. My roasted cauliflower comes out very nice; I'm working on sauces instead of herbs now as I need to keep it interesting and the BF prefers more complex food. I have done that with broccolini already, but do not think it will convert from green to white vegatable, although the theory will. Once again Tony M thank you much.

Is there any way that I can make purple mashed potatoes ?? I think it will look really good but I heard that after boiling purples potatoes they tend to loose their beautiful color ...

To make purple mashed potatoes is really just the same as making regular mashed potatoes. The darker the purple the more deep the color will be, but when cooked they usually do loose some color. I personally have never been able to keep that deep color when cooked.

Here is a recipe from another blog site for purple mashed potatoes - http://www.restaurantwidow.com/2007/07/pretty-purple-p.html
Here's another link for purple potato gratin with bacon - http://www.eatingoutloud.com/2008/02/purple-potato-gratin-with-bacon.html

Happy Cooking!

Thank you very much I'll try that ...

Do you think that steaming would retain the color in purple potatoes? I know it's a nice way to prepare taters for mashing.

I think that steaming would help to retain some of the color because the potatoes will be will be in less water.

Another eye opening lesson, thanks!

I have a question. Why in almost all cooking, e.g. vegetables, pasta, et al is one told to begin with cold water? I asked that question in Tuscany during a cooking class and the answer was something about hot water might have more "rust from the pipes" than would the cold water. I think there was a language problem in the Q and A. Please give me an explanation that makes sense, or is it just habit?

The reason for this is - as you said - because water is heated by hot metal which can lend water a metallic taste which is undesirable, always use cold water, some times you actually need to use filtered or bottled water

Despite the language barrier, your Tuscan teacher was correct. Hot water can absorb off flavors from sitting in heating tanks and pipes. Depending on where you live and how old your hot water system is, this can be more of an issue for some. Here at Rouxbe, we prefer to start with cold water (especially when making stock or cooking pasta/vegetables).

There is a lot of discussion on the subject (see this thread on Chowhound). Hope this helps.

According to "The Silver Spoon" in it's "Cooking Terms" section there is the following:

Add While Cold
To add an ingredient to a liquid or sauce before heating. For example, meat it put in cold water when the flavour of the stock is more important than that of the meat.

Add While hot
To add an ingredient to a hot or boiling liquid or sauce. For example, meat is put in hot water when the flavour of the meat is more important than that of the stock.

I've always taken this to mean that starting from cold is liable to leach more flavour out of the ingredient added (ie. if you were making stock, you'd want to start with cold water)

I think that you may be misunderstanding the response above. We were referring to the water that is coming from the tap (before the cooking even starts). We were saying that it is best to start with cold tap water rather than hot tap water, as hot tap water can sometimes have off flavors from the pipes.

You are correct in what you were saying about adding ingredients to cold or hot water.

Hope this clears things up for you. Cheers!

Is there method to preserve exposed bananas for a short time.
Relative to the veggie preservation video I should submerge them in a "acid" water. Is this correct?

Carlos

If you squeeze a bit of lemon juie onto the bananas, like when making a fruit salad, it will help keep them from going too brown; however eventually they will go mushy. I would not suggest that you submerge them in an acid water as this will only make them mushy. For the best results, peel and eat or use the banana immediately. Cheers!

I am still a bit confused about the acid matter with lid on and lid out. What is the difference between the natural acids of green vegetables that cannot condensate with the lid on, and the acid added to the liquid with other pigment families, that can condensate with the lid on?

Green veg pigment, chlorophyll, reacts adversely with all acids - all other pigments do not, in fact most welcome it. When cooking veg in water, some acids are released by the veg at the surface level. With a lid on, these acids condensate and can denature the green pigment. Other pigments are not affected, but often require additional concentration of acids (especially white and red pigments) to preserve their colour.

thanks a lot....it helps me to my culinary lesson!!!