My sister took my place in the spotlight, but

Question

Berry was supposed to be studying for her big chemistry exam, when she came up with this riddle instead and just had to post it:

I am extinct, yet pretty much everybody knows what I am like.

Despite what my name sounds like, I am not disgusting at all.

My sister took my place in the spotlight, but nobody thinks she is as sweet as I am to people.

You can still see me in the frozen aisle of most grocery stores.

On the periodic table, I am considered to be three metals that do not fit perfectly together.

(The first sentence may or may not apply to me right now... :P )

HINT:

The first sentence holds an important clue (especially the bold word).

HINT #2:

The bold word relates to the category that the "thing" is in.

HINT #3:

You might find the answer quite "appealing".

Answer 1

Are you a

Gros Michel Banana? It's often known as Big Mike or Fat Michel/Mike.

I am extinct, yet pretty much everybody knows what I am like.

It was the most common banana in the world before the 1950s.

Despite what my name sounds like, I am not disgusting at all.

It sounds "gross" but it isn't.

My sister took my place in the spotlight, but nobody thinks she is as sweet as I am to people.

Cavendish subcultivars replaced Gros Michel bananas thanks to Panama disease in the 1950s. Gros Michels were sweeter and creamier than the current Cavendish bananas.

You can still see me in the frozen aisle of most grocery stores.

Frozen bananas can be found in the frozen aisles of grocery stores; they also come in strawberry banana foods and ice creams.

On the periodic table, I am considered to be three metals that do not fit perfectly together.

Barium + Sodium + Sodium = Ba+Na+Na = Banana.

Hints:

Bananas are botanically members of the berry family (second hint); they also have peels (third hint).

Answer 2

Maybe it's

Mars

I am extinct, yet pretty much everybody knows what I am like.

The planet Mars is now a dead celestial body. Pretty much everybody knows what it is.

Despite what my name sounds like, I am not disgusting at all.

Probably a wordplay with "to mar" meaning "to damage". The Mars bar is pretty good actually.

My sister took my place in the spotlight, but nobody thinks she is as sweet as I am to people.

The sister here is the Moon which the world was focused on until recently but which is less inhabitable than Mars.

You can still see me in the frozen aisle of most grocery stores.

A wordplay with the Mars bar which has a frozen variant.

On the periodic table, I am considered to be three metals that do not fit perfectly together.

With the letters from Mars, you can build the chemical symbols Am (americium), Sr (strontium) and Sa (Samarium) which are three metals.

(The first sentence may or may not apply to me right now... :P )

An allusion to recent evidences that there may be life on Mars.

Answer 3

Are you a

Raspberry?

I am extinct, yet pretty much everybody knows what I am like.

The original raspberry species may be extinct but current new species are not.

Despite what my name sounds like, I am not disgusting at all.

Blowing raspberries are sounds used to signify derision or disapproval (maybe raspy = disgusting as well?).

My sister took my place in the spotlight, but nobody thinks she is as sweet as I am to people.

Raspberries are part of the rose family, but roses aren’t as sweet as raspberries.

You can still see me in the frozen aisle of most grocery stores.

Raspberries can be found in frozen fruit.

On the periodic table, I am considered to be three metals that do not fit perfectly together.

Radium + Sulfur + Phosphorus = RaSP (three elements, yes I know not all metals, that don’t fit perfectly together). Or if we use the commonly misused elements, Radium + Sodium + Potassium = RaSP (even though Sodium = Na and Potassium = K).