Sorry, but you're not convincing me as what you feed it (out of the four default foods) doesn't matter.
Here's my methods of getting Tamagotchi:
Tensaitchi
Version: 4
Family: Mame
Recommended teacher: Mr. Turtlepedia
Recommended foods: Melon, Icecream, Beef, Omelet, Fish
How to get: After getting a Yangu Mametchi or Yangu Robotchi, you'll need to raise your Intelligence skill points. Choose Mr. Turtlepedia as the teacher. Keep a lookout for the recommended foods, these raise intelligence points (the melon actually raises all of the points up by 1). Make sure intelligence points are highest so you'll get Mametchi as an adult. Before the matchmaker's first visit, raise your intelligence points to at least 350 and have a combined total of at least 100 in the other two areas.
Makiko
Version: 4
Family: Meme
Recommended teacher: Ms. Flower
Recommended foods: Melon, Donut, Cherries, Cupcake, Cheesecake
How to get: After getting a Yangu Memetchi or Ichigotchi, you'll need to raise your Style skill points. Choose Ms. Flower as the teacher. Keep a lookout for the recommended foods, these raise style points (the melon actually raises all of the points up by 1). Make sure style points are highest so you'll get Memetchi as an adult. Before the matchmaker's first visit, raise your style points to at least 350 and have a combined total of at least 100 in the other two areas.
Nonbiritchi
Version: 4
Family: Kuchi
Recommended teacher: Mr. Canvas
Recommended foods: Melon, Grapes, Sandwich, Corn, Bananas
How to get: After getting a Yangu Kuchipatchi or Oniontchi, you'll need to raise your Kindness skill points. Choose Mr. Canvas as the teacher. Keep a lookout for the recommended foods, these raise kindness points (the melon actually raises all of the points up by 1). Make sure kindness points are highest so you'll get Kuchipatchi as an adult. Before the matchmaker's first visit, raise your kindness points to at least 350 and have a combined total of at least 100 in the other two areas.