The problem with using other acids is that while they will work, they don't work as efficiently to prevent browning. Ascorbic acid is the speediest inhibitor and it has the greatest long-range effect (slows browning the most). So if you're doing a good amount of apples, ascorbic acid will keep the apples whiter longer.

It's basically 1/2 tsp. per 2 1/2 cups of water or its crushed equivalent in tablets. If the tablets aren't pure vitamin C, you may want to up the amount a little.

Carol

I forgot to add for larger amounts. 6 Vitamin C tablets per gallon. If there are fillers in the tablets water may be cloudy but it's harmless.

Carol

Vitamin C tabs can also contain starch, binders, or other fillers, something you usually don't want to add to a dip. Another alternative is the use of sulfur. Wine making supply stores offer both. The sulfur is also a powder and is used to prevent browning as well, but some people are sensitive to sulfur, sodium metabysulfate or potassium metabysulfite. In any case ascorbic acid is probably the better choice. You just simply are making a 'dip' for the apples. The ascorbic acid solution you dip them in for about 1 minute, then drain, but do not rinse or pat dry. The small residual amount will attach itself to the apple slices. You can find ascorbic at many nature food stores, as well as on line. It only needs to be food grade ascorbic acid. A while back I got a great deal on a pound of it, only to find it was not a food grade ascorbic, so its used as an anti-fungal spray on my outdoor plants instead.

I dried many potato slices and without ascorbic or sulfur, they turn black. I tested both dips and found the sulfur dip worked better there.

Lemon juice works better than vit. C tablets I think.

Dave

Lemon juice has only about 35% ascorbic or vit C. Its more for flavor as opposed to color retention and oxidation protection.

You know, you can buy powdered Vitamin C in a pharmacy (not powdered....more like crystallized/granulated). It's handy to have a bottle on hand, not only for canning (to limit oxidation) but also to improve bread doughs, if you're a baker. And of course, it's cheaper than Fruit Fresh, and you don't have to crush Vitamin C tablets. I used about 1/4 teaspoon per pint when I made Vidalia onion relish a few months ago, and the jars are still bright yellow! And I added about 1/2 teaspoon per quart of applesauce that I made yesterday.

Hope this helps--Gina

Here is a link that might be useful: Lindsey's Luscious (my food blog)

Thanks all -- Carol, your post was particularly helpful since a source I saw online said I needed something like 4 Tablespoons of crushed tablets per liter, which seemed really excessive... And Gina, I'm actually already a fan of your blog, so its nice to know you post here. I'll take a look for granulated Vitamin C in the drugstore...

Emily

As metioned, Vit C tablets contain corn starch and other fillers and binders. That may be the reason a lot of tabs need to be crushed. If I don't know whats in a vitamin C tablet beyond the C, I will never use them in canning. Even for that powdered Vitamin C may also have things like silicone dioxide as an anti caking agent or other additives. Just be sure that if you do use a vitamin C, that is got enough of the REFINED ascorbic acid to be effective. Canned goods like apple sauce will not usually darken right off, but the inside surface will start to brown after about a month or so, if there was no, or very little, ascorbic added.

I use the crystals, but sometimes they can be difficult to locate on short notice. An alternative is to look for tablets without fillers. There are a few brands out there in health food sections.

Carol

When I buy Citric, I usually get a big 1-2 pound bag. Ascorbic is also found on line in half pound bottles from some on like drug stores. That way, I will not easily run out soon. I also keep a big bag of the acid blend here too. Below is a site that sells an 8 ound amount and a 3 pound jar. Its still cheaper than the Fruit Fresh..

Citric acid source- http://www.myspicesage.com/citricacid.html?gclid=CPDYwo7ik5YCFQO2FQodHzLzFQ

Here is a link that might be useful: Ascorbic Acid

Great info all above! i am getting ready to cut up apples to freeze for future pies this winter and all I have are 1000 mg vitamin C, from only ascorbic acid, capsules. easy to open and in very very fine powder form so should mix with water decently. Glad this thread is still here.

OP is discussing dehydration. I don’t acidulate apples for freezing at all.