Over time fresh basil gives it a bitter metallic aftertaste for us. Learned that the hard way. ;) So you need to go VERY easy on it - less is better.

Using dried basil gives better results in my experience. Or add the fresh leaves whole while it is cooking but remove them before filling the jars. You can even put the leaves in a cheesecloth spice bag - makes it easier to remove them. Then taste before jarring to see if you may want to add a bit of sugar.

Dave

Thanks dave - I will try adding fresh leaves while cooking and removing them before jarring. With that - there would be no change to my process - still use 2 tbs of lemon and bwb as I have in the past?

I have put small amounts of fresh basil leaves, and also of fresh garlic, in with tomato sauce. Similar amounts to what you're thinking---I would put just 2 or 3 leaves in a pint jar, and a half-clove of garlic. From looking at approved recipes for seasoned sauces with various additions, I felt quite confident that that small amount of low-acid stuff wouldn't change the process or amount of lemon juice I needed.

Mostly I've stopped bothering, though, because the effect was so subtle. To make a sauce taste really basil-y you need to add a LOT, and that can become bitter over time as Dave says. So mostly I make big batches of plain sauce and small batches of an approved pasta-ready seasoned sauce for just plunking over spaghetti on a tired night.

THough a jar with a bit garlic clove and a sprig of basil looks nice for gift-giving! ;-)

Zabby

Yes, I used to add a couple of leaves per jar, but some basil has an off bitter taste that will not go well. Its always better to add the herbs at heating and serving time. On the other hand a few dried thyme leaves or oregano leaves will work well.