This was announced tonight but buried away on the 'website articles' forum, but it was very useful info on the new provisioning system so thought I'd paste a copy here for people:

MSchroeder mod
10:18PM edited 10:21PM Staff Post
I’d like to take a moment and address some of the questions that have come up in this thread so far. We’re all excited to hear your feedback, and I wanted to allay a few fears. Some of this is information we’ve shared before, but I figured it would be helpful to address as much as possible here.

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1. “What happens to all of my ingredients? How do I get new ingredients I might need?”

Some ingredients will be marked as “Old”. They will no longer be used in Provisioning. However, we’ve set their value to be the same as the price of buying a new ingredient. Grocers will be selling ALL non-rare ingredients, so visiting one is recommended as a one-stop shop for your Provisioning needs. Further, Chefs will be selling all non-rare Food ingredients, and Brewers will be selling all non-rare Drink ingredients. We'll be monitoring the price of player-sold Provisioning items, as well as feedback on this and other forums, to see if and when this pricing schema should change.

Those ingredients that aren’t becoming “Old” or “Stale” will remain useful in Provisioning. However, their names and icons might change. For instance, this is the case with Oats and Tomatoes, generally considered the rarest of all Provisioning ingredients today. After the revamp, they will still be required for purple recipes, but they will change icons and names. So don’t rush off and sell all your tomatoes and oats, thinking they will become commonplace!

Of course, there are many other ways to get ingredients, as well. Like we mentioned in the article, you can now skin fish for use in meat dishes. As ever, you can check in crates, barrels, boxes, and many other places to find spare ingredients just lying around – though now this may incur the wrath of justice. You’ll also find provisioning materials on critters in the wild, as well as receiving materials of all kinds from your Hirelings and any Writs you complete.

2. “What happens to all of my recipes?”

You will still know all of your recipes. No recipes will be ‘forgotten’. However, much like the ingredients that remain, their names and the ingredients they use will change. The rest of any recipe will generally remain the same:
• All recipes have retained their quality. If you knew a purple recipe before the revamp, you will still know a purple recipe afterwards.
• All recipes remain food or drink. If a recipe was a food recipe before the revamp, it will still be a food recipe afterwards (and the same for drink recipes).
• The vast majority of recipes have retained their level. The few recipes that have changed level, have only had their level increase, to ensure maximum value for your effort.

3. “What about VR 10 recipes?”

With the Provisioner Revamp, we are introducing new Veteran Rank 10 recipes. As brand-new recipes, you will have to go out into the world and find them, much like before – no matter how many recipes you might already know.

4. “What happens to all of the foods and drinks I’ve already made?”

They will all still be edible and useful. Many of the foods and drinks you’ve made before will remain as they are today; not even their names will change (they won’t become “old”) – you just won’t be able to make them anymore. Some foods will change their names and icons, but will still be as useful as before.

5. “What’s happening with Drinks?”

During the design phase of the Provisioner revamp, we discussed the possibility of allowing players to use both a food and a drink at the same time. However, we’ve decided at this time that we want there to be an interesting choice between food and drink – some situations call for food, while other situations call for drink. To this end, we’ve improved the regeneration(s) granted by drinks by a significant margin, but we’ve left food and drink unable to stack with one another.

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We’ll be watching the usage of food and drink on PTS, and going forward on Live. If feedback and metrics show that drinks remain widely unused after the improvements, we will review our options (including but not limited to making them stack) and act accordingly.

forums.elderscrollsonline.com/discussion/146599/official-discussion-thread-for-update-6-guide-provisioning/p2