In my experience, whether or not you peel a fruit or vegetable has more to do with how easy it is to digest than any level of toxins. If you're going into the realm of herbs, however, then you need to be more careful, as some are quite potent. But as long as we're sticking to fruits and veggies, here's my advice, and it's pretty simple:
Clearly things like melons, and corn don't have edible peels, simply because their outer layer is too difficult for us to masticate, and then digest... Things like citrus peels can be digested, but not when they're raw. They need to be pickled, cooked (think of marmalade) or turned into a zest. When it comes to soft, thin peels, like apples, pears and kiwi, it's more of a personal preference. Some don't like the feel of a furry kiwi slice going down, but I don't mind it, so I slice it right into my cereal.
In the realm of veggies... Yes, stems are great for you. If it's really difficult to chew it, it's not going to be broken down enough for your stomach to handle it, and extract anything useful from it. Ex: Broccoli stems - they'll benefit even from some light steaming, and they're GREAT for you. But raw? Rather difficult. The florets however are a classic raw snack. That's my general guideline. Same with artichokes. They need some kind of cooking in order to be digested. But carrots? Kale? Celery? Simple chewing pulls them apart enough to make the extraction of nutrients easy for the body.
Hope that helps!
Mindy
P.S. A great tip for raw kale - not everyone likes the consistency of raw kale because you have to chew it for soooo long. BUT, if you massage it with a bit of lemon juice, and a touch of olive oil until it softens, and the color brightens (5 minutes or less), it's easier to chew, very tasty, and you haven't cooked any of the nutrients out of it!
I would do two things to make them more palatable.
- Boil the briefly (5-10 mins depending on how hard of a veg they are) in salted water. Something like a tablespoon of kosher salt per 4 quarts water (3.7L water).
- After they are parboiled, I then will saute, simmer, or braise (depending on the recipe/mood/vegetable) in a highly flavored sauce or spice mix until they are cooked.
So if I was cooking the carrots and (green/string?) beans and wanted to use chili powder I would chop some onion and saute that in olive oil while the other veg parboils. Then, add 1-2 tablespoons chili powder to the onions (and maybe some garlic, because everything is better with garlic) and let those flavors meld while you drain the veg. Once you have the veggies drained add them to the onions and spice with a bit of liquid (wine, beer, stock; maybe 1/2 cup) and let them cook on low until they are as done as you would like them.
Best Answer
I suppose dropping the bags in liquid nitrogen for a few minutes, and then storing in the freezer might suffice.
mostly fish, but not a bad read: http://www.fda.gov/downloads/Food/GuidanceRegulation/UCM252416.pdf
Edit post clarification of the question:
Liquid nitrogen is still fun if you can find an excuse, and highly effective.
In a less drastic direction, simply doing the processing on pre-cooled (below 38F, preferably 33F) vegetables (and preferably in a walk-in cooler held below 38F) should keep things out of the botulism growth zone, and putting them in a -20F freezer for long enough (do some test runs where you actually stick a thermometer in a test bag) to get the center of the mass down below 0F before transfer to a 0F freezer (assuming that's your standard freezer temperature) would likely suffice. A cold brine step might help freezing get started faster but would be messy as compared to just using a -20F freezer (perhaps with racks to separate bags and extra air circulation, so you don't have bags packed together until after they are frozen through.) Depending on scale, maybe just size the -20F unit for a days production and clear it out at the start of each day after holding product overnight.
If processing in a warmer environment, you'll want to minimize time between "being held pre-cooled" and "being packed and frozen" - and especially "time between being vacuum-packed and being frozen." But giving the workers warm coats and hot coffee (and breaks) while working in a cooler will be safest. You will also need to sanitize any equipment on a regular schedule, which will be more often if they are not cold (and you'll need to check the temperature of the food contact parts of any machines when they have been running for a while.)