Check this out http://www.foodscience.csiro.au/oilvine-text.htm it's about botulism growth in preserved veg.

The slimy stuff is probably not botulism (but probably contains it, hopefully at low enough levels to prevent illness). It's probably just the peppers dissolving slightly in the oil. Refrigeration would help.

Why do you use hot olive oil? It's not going to be any more sterile and you could be destroying the good parts of the oil. I suggest adding a good slug of vinegar and then the cold/room temperature oil. That should take care of any nasties.

whenever i do roasted peppers i end up just freezing them in portioned zip bags.. they thaw perfectly and then you can pull out 1 bag at a time to  put them in a jar and add some good oil to keep in fridge . when your close to done that jar pull another zip bag out of the freezer and your laughing... i will also tend to add any extra veggies i have grilled to the jar .. grilled  asparagus or mushrooms or eggplant  marinated in with the peppers for a day or two  is wicked on any sandwich.       mm this is making me soo hungry now.

I'm just in the process of making this now.  I'm taking a recipe from River Cottage Preserves book (p198).  It is originally for Asparagus preserved in oil but suggests substituting with char-grilled peppers.

It brings 200ml of water and 300 ml of cider or white wine vinegar to the boil, then it's removed from the heat and covered to keep warm.  The char grilled veg are dipped into the hot vinegar bath and left for 3-4 minutes.  "This sharpens the flavour of te asparagus (or in this case pepper), while the acidity assists in preventing bacterial growth."

Remove from the vinegar bath, pack it into the jar with herbs, etc.  Add 70ml lemon juice to the jar (again for acidity to fight bacteria) and then add olive oil (unheated).  Store in cool, dark place, leave 6 weeks to mature.  Consume within 4 months.  Store in fridge once opened.

I'm going to try Ashen's freezer portion idea too, and see which works the best.

This may seem a bit odd, but....I think the idea of freezing peppers, whether they be raw or roasted is great. But when you take them out and want to put them into a jar of oil, perhaps for a few weeks before use, could you use cheaper vegetable oil, rather than olive oil? If you added some fresh herbs such as rosemary, thyme, mint, would the taste be as good? and perhaps less calories?

Thanks, Ashen. Good info!