WineLovers Discussion Group

Patricia Wells says it does. I'm doing a first-time gratin recipe from her book Simply French for dinner (recipe tomorrow) involving tomatoes, onions and potatoes. She recommends a tablespoon of sugar to reduce the acidity in the tomatoes whose acidty will make it difficult for the potatoes to cook fully. The latter, I get. Been there, seen it. But the former? I can understand why it might TASTE less acidic, but I'm surprised to read that it would actually cut the acidity. And I'm not quite prepared to believe it....

Consider a high acid wine (Riesling, for example). The same wine, bone dry, will taste more sour than the same wine with even a small amount of residual sugar. I don't see why the same wouldn't apply to tomatoes.

Sugar does not reduce or remove acidity, it merely masks it. In the wine example, if a bottle of dry wine has 7 g/l of acidity and you give it a dosage of 12 g/l of sugar (like a German Halbtrocken) it still has the 7 g/l of acidity, you just do not taste it the same way.

Jenise wrote:I can understand why it might TASTE less acidic, but I'm surprised to read that it would actually cut the acidity. And I'm not quite prepared to believe it....

I think that's just careless wording on Well's (or her editor's) part. I agree with David: Sugar masks acidity, in food and in wine, and that's why virtually every cuisine in the world, from German to Italian to Chinese, features "sweet and sour" dishes.

It's interesting thinking about the premise for the question though. The chefs statement is that the acidity in the tomato makes it difficult for the potato to cook fully. Jenise says she's witnessed this phenomenon. If sugar just masks acidity, and the acidity is still there, wont the potato cooking be equally difficult with or without the sugar? Or is there something more chemically complex going on here?

But she wasn't talking about taste, Howie. Like I said, that I understand. She said it would actually reduce the acidity which would otherwise inhibit the cooking of the potatoes. Baking soda would do that, but sugar?

David and Robin--that's exactly what I thought. And Robin, the wording is what it is--she adds sugar to the gratin and states that it's for that purpose, there's no other way to read it.

Bill--what I know about acidity is that it causes toughening, or contraction. I've never potatoes in an acidic environment before, but her assertion that acidity would make it harder for potatoes to cook fully (at least, without longer cooking time) makes sense to me. That adding sugar would somehow chemical neutralize the acidity, though, that didn't make any sense at all. I'll post the recipe so you guys can look at it.

Perhaps the addition of sugar raises the boiling point of the liquids to help facilitate the cooking of the potatoes in the same manner that syrups have higher boiling points than water. Just a thought.

Jenise wrote:Patricia Wells says it does. I'm doing a first-time gratin recipe from her book Simply French for dinner (recipe tomorrow) involving tomatoes, onions and potatoes. She recommends a tablespoon of sugar to reduce the acidity in the tomatoes whose acidty will make it difficult for the potatoes to cook fully. The latter, I get. Been there, seen it. But the former? I can understand why it might TASTE less acidic, but I'm surprised to read that it would actually cut the acidity. And I'm not quite prepared to believe it....

My strong feeling is the sugar, when all is said and done, would, principally, make the dish sweeter. The rest is something to talk about.

ChefCarey wrote:

Jenise wrote:Patricia Wells says it does. I'm doing a first-time gratin recipe from her book Simply French for dinner (recipe tomorrow) involving tomatoes, onions and potatoes. She recommends a tablespoon of sugar to reduce the acidity in the tomatoes whose acidty will make it difficult for the potatoes to cook fully. The latter, I get. Been there, seen it. But the former? I can understand why it might TASTE less acidic, but I'm surprised to read that it would actually cut the acidity. And I'm not quite prepared to believe it....

My strong feeling is the sugar, when all is said and done, would, principally, make the dish sweeter. The rest is something to talk about.

Of course given the sorry state of tomatoes in today's marketplace the sugar might actually just get the dish to where it should be in terms ofs weetness.

ChefCarey wrote:My strong feeling is the sugar, when all is said and done, would, principally, make the dish sweeter. The rest is something to talk about.

What I concluded, so I left it out. And the dish cooked in the prescribed amount of time anyway.

>Amylase is also synthesised in the fruit of plants during ripening, causing them to become sweeter.

Like I said...

Agree with the others - it masks the acidity and makes you taste it differently. In wine,

Alcohol + Sugar = Acidity + Tannin

Just because you don't taste the tannin in Zinfandel doesn't mean it isn't there.

(As mentioned) Just because you don't taste the acidity in halbtrocken, doesn't mean it's not there.

etc, etc.

John D. Zuccarino wrote:The sugar helps inhance the Amylase
Amylase is a digestive enzyme classified as a saccharidase (an enzyme that cleaves polysaccharides).

I understand what amylase is and what it does. What I don't understand is how a disaccharide such as sucrose (table sugar) enhances the enzyme's activity. And I don't understand the connection between amylase and the process of cooking potatoes. Is there amylase present in the potatoes that performs starch breakdown as they cook? I thought the potato-cooking process was more a matter of partial breakdown of the potato starches (amylose and amylopectin) by heat.

I would have expected added sugar to make the acidity of the tomatoes less noticeable on the palate (just as it makes acidity in wine less noticeable), but that it would not affect the cooking process for the potatoes any.

-Paul W.

John,

So the presence of free disaccharides such as sucrose promotes the action of the amylase present in the potato cells, thus promoting the starch breakdown?

One would assume, since acidity seems to make potatoes and other starches take longer to cook, that low pH inhibits the action of amylase.

Does that all make sense?

-Paul W.

This would seem to imply that amylase is pretty heat-stable, unlike many other enzymes that are denatured by heat.

-Paul W.

My strong feeling is the sugar, when all is said and done, would, principally, make the dish sweeter. The rest is something to talk about.

Chef, you relly cut to the chase don''t you? BTW,I agree with you.

"Chef, you relly cut to the chase don''t you? BTW,I agree with you."

I am not well known for bullshit-abiding.

I was not criticizing *you.* (Yes, even paranoids have enemies.) I have dwelled in many of those corridors myself. With a major in English literature and triple minors in history, comparative literature and philosophy, I had many undergraduate - and graduate - all-nighters. Socrates was always there, as were Buddha, Jesus Christ, Aristotle, Kant, Hegel, Hobbes, Locke, Kierkegaard, Joyce and Gerard Manley Hopkins. I cannot be bludgeoned by scholarship.