6/26/2013 Addendum: I just wanted to say that from the comments down below, what the Ga people of Ghana call alasa is NOT the abiu/yellow star apple (Pouteria caimito) but instead the white star apple, Chrysophyllum albidum, which is also known as the African star apple. It too is in the Sapotaceae family so I was not too far off initially in 2007. Read here for more information on this fruit.
Someone asked for the nutritional analysis of alasa in the comments section. If you have access to the Journal of the Science of Food and Agriculture, you might be able to get access to this 1982 Nigerian article, Nutritional value & mineral contents of Chrysophyllum albidum fruit. This other scientific article states that it has 100 times the vitamin C levels of an orange. Now that’s impressive!
People in the comments have provided other local names. Adisaa in Twi. Udara in Igbo (Nigeria). Thanks readers and commentators. This has been a very exciting process. I’m especially pleased with the bonus identification of yooyi as velvet tamarind (Dialium indum).