For those looking for a way to predict Nectar Flavor Quality (Amazing/Great/etc.), here's what I've found out after digging through the game's code. There's no set table or way that EA determines the flavor quality. Below is a long explanation as to why.
It takes the names of your 10 ingredients, lines them up alphabetically (e.g. "Apple, Apple, Grape, Grape, Grape, Life Fruit, etc."), and then dumps them into a "Randomizing" algorithm. The reason I put random in quotes is because the same recipe will consistently produce the same flavor quality nectar (at least on the same computer). (Sorry if I'm bursting anyone's bubble that random numbers generated from a computer aren't really random.) As such, without replicating the Randomizing algorithm outside of the game, it's not possible to predict Flavor Quality (since changing one letter in one name would be sufficient to give you a completely different flavor quality, and we can't even do that - we have to change out a whole fruit).
Additionally, this may explain why amazing recipes vary on some people's computers. I haven't taken a look at EA's Randomizing algorithm directly (I just see that they're using a function called "Random"), but I know from experience with other programs that random algorithms can either be implemented directly within the code of a program, or they can use something from the computer they're operating on in order to generate the random numbers. Now, given the consistency that we've seen, I would think that the random algorithm they're using here is dependent only on their code, but perhaps within their code they do use something else besides just the formula to generate the random number (like a numeric value corresponding to the language you're using? - If the names they're using to generate the Apple, Apple, Grape, Grape list is based on the current user's language, this would seem very plausible.)
Anyway, I wasted a bunch of time on this and hopefully can save some people some time. If anyone's ambitious and thinks they can replicate EA's randomizer code, I'll tell them where to find it.