Why is my icecream bitter?

Melon should be fine in ice cream, I think yours was just a bad specimen. While you say it was not as bitter fresh it still was not a tasty melon, its possible that during the puree/ice cream making process the combination of ingredients enhanced the bitterness.

Your best bet would be to try again but insure that the melon you start with is good and sweet. I have never used guar gum making ice cream before, so I don't know if you are better off leaving it out or not.

It's no surprise to me that you describe the final taste as being similar to a raw gherkin, because both melons and gherkins are closely related to the cucumber.

Melons actually do have bitter notes; according to McGee, they contain "green, grassy compounds" as well as sulfur compounds, the latter being the same sort of thing you'd find in garlic.

Since melons only get sweeter on the vine, I would assume that the general blandness was caused by the melons being harvested too early and possibly sitting on the grocery store shelf for a long time.

If there was noticeable bitterness beyond what you tasted in the raw fruit, it was probably just because you got a concentrated dose of it in puree form. Overcooking it would also increase the bitterness, but you say it wasn't exposed to heat (could the custard still have been very hot when you incorporated the melon?).

There is no way it was a reaction with guar gum - it's a very common additive in melon-based drinks and desserts. It's also extremely unlikely to have been a normal reaction with the cream; I've made melon mousse and other dairy items with melon and never noticed any kind of unusual bitterness.

The only other possibility I can think of is that there may have been a problem with the cream itself. This varies quite a bit from brand to brand and region to region, but most of the time, the "cream" you buy does not just have cream in it; for example, I'm looking at a typical supermarket carton that contains cream, milk, skim milk powder, dextrose, and a bunch of E numbers, and even some sodium citrate. These creams can easily take on bitterness before they go sour. So if you were using the typical supermarket brand of heavy cream, and it was sitting in your fridge for a while, that may have been a contributing factor.

All in all, I think it was probably a very random and unfortunate combination of factors that would have been due to the specific ingredients used rather than the types of ingredients. I doubt you'd get the same results if you tried again with fresh melons, cream, and eggs.

I had the same exact problem with both melon ice creame and pineapple ice cream. I tasted the ingredients before mixing them (cold). The bitterness came after the mixture left sit in the refrigerator for a while. I suspect the fruites had a chemicals reaction to stainless stell pot I left the mixture in but not sure what caused it....

I would like to answer your question based on my personal experience with honeydew melon, because I always want to prepare honeydew melon when it is available in the market. Adding sugar and water to the melon will not introduce bitterness in the mixture, however the moment I add milk (evaporated or condensed) and after mixing, the result will be a bitter mixture. So there is really a negative result combining milk and honeydew melon.

I had a similar problem with pineapple ice cream and found this: http://www.all-about-food.org/tips/faq/milk-become-bitter-kiwi.php

From this page:

Why does milk become bitter if you add kiwi?

If you combine milk, yogurt or curd with fresh kiwifruit, it will become bitter and viscous.

The reason for this unpleasant effect is due to the proteolytic enzyme actinidin of the kiwifruit. This enzyme breaks down milk proteins (casein) into smaller sub-units (peptides, amino acids), which are responsible for the bitter taste. Pineapple and papaya can also make milk taste bitter because of its proteolytic enzymes bromelain (in pineapple) and papain (in papaya).

After reading all questions and answers I am still left with out an answer to my question.

I have made pineapple ice cream and papaya ice cream and to my astonishment it was so bitter! I used fresh pineapple, it came out bitter with the custard base, then I used the one from the tins and it was perfect. So I went and do a research and found out that when using fresh pineapples you should first cook it with some sugar. I have not tried it as yet.

As to the papaya I was so disappointed. The pureed papaya was not bitter, the custard was not bitter, and when I combined the fruit with the custard it was not bitter! But while in the Ice Cream maker I tasted it and could not believe what I tasted so I tasted again and it was very bitter, more than the pineapple, so maybe I have to cook the papaya with sugar first too.

I hope this info is of some use to others.

I just made cantaloupe gelato base for the first time and had this problem too. I added a bit more sugar and some lime juice and so far it's much more edible, lol. Bitter flavors are usually basic, so maybe the acid is helping neutralize it?