Artisan Good Questions:

[Vertumage]

Is it better, to pickle veggies, or jam fruits, or does it not matter too much. I am using kegs mainly to make pale ale, and blueberry and cranberry wines.

[SNEED]

just use whatever has the highest base price per item, so big stuff like starfruit, melons, pumpkins etc

[abbi]

blueberries sell for 50, 62 and 75 (regular to gold quality). With tiller profession its 55, 68 and 82.
made into wine, they sell for 150, 187, 225 and 300, and 210, 262, 315 and 420 with the artisan profession. If you make preserves, they sell for 150 and 210 (with artisan profession) So, it makes more sense to make wine vs preserves if you have enough kegs.

[Numbers]

Wine sells for more at the end but preserving stuff produces more "gold per day" since it's a lot faster. I personally just keep a full cellar worth of starfruit wine coming from the greenhouse for aging and put the rest of my farming output in preservative barrels.

Edit: Processing farm things into artisan goods will always produce more gold but it's got the time cost as well. I don't think twice about dumping raw goods for quick cash if I need to. Artisan is for long term income.

[desertpunk3912]

Best to check the wiki. In general veggies are worth more pickled and fruit is worth more fermented into wine. Blue, black, and salmonberries are better turned to jam. They're worth the same as wine in half the time. Hops and wheat are worth more as beer. Pumpkin and cabbage are worth more as juice.

https://stardewvalleywiki.com/Preserves_Jar

https://stardewvalleywiki.com/Keg

[I Kinda Fail]

My rule of thumb is typically...

If the produce has silver or gold star, sell it, unless it's a loved gift. (Like pumpkins, melons, strawberries)

If it has no stars, keep it, and have a big fat stack of 'em. I try to keep a few of everything from that season in a chest, but I still have one "main" crop per season whose sole purpose is conversion. My strawberries became wine until I was able to get a bunch of starfruit. My massive blueberry crop for making jelly was swapped out for cranberry jelly; I now keep 1 stack of blueberries in reserve, and sold all the rest. I replaced the 24 blueberry plants in my greenhouse with coffee.

Short version: Hops and wheat always become beer. Expensive stuff like starfruit or melons are typically better as wine or juice. Cheap stuff like green beans or blueberries are better as jelly and pickles.

[FunWithEndermen]

I'd like to add: keep everything you'll need for the community center bundles unless you've done them all already.
Second, keep at least one of each vegetable because you get a seed maker somewhere around the second year. You can make your own seeds and not have to buy them. This includes ancient seeds and gem berries (fruits)?
If you haven't got the mayor's shorts yet keep a melon to make a pink cake. Give it to Marnie on her birthday.
And if you have not yet won the grange display keep some gold pumpkins and melon jelly. That will help you win.

[Snowy Sprout]

Based on the time it takes to work vs profit made, I would say pickle everything, make beer or pale ale in kegs, and use casks to age cheese. the only exception is ancient fruit wine, which is my end-game goal for the greenhouse and a shed full of kegs, to make a full-on winery.

[ignis]

Jar: 2 x base + 50 for everything
Keg: 3 x base for fruits, 2.25 x base for vegetables

Fruits are usually better in kegs, but ones with less than 50 base sell price are better in jars.
Vegetables almost always are better in kegs, unless their base sell price is over 200 (pumpkins and red cabbage).

But since jars are also much faster, kegs outperform jars only for beer and ale. Still, wine has its benefits - you don't need to reload kegs every second day, you don't need as much farming space and it is good to use with casks for max profit (melon, starfruit or ancient fruit wine).