I don't think racism is a problem only in Singapore. It's everywhere and that's just a sad fact of life. You either choose to take it personally, or ignore it and enjoy life.
The panel of interviewers will be objective, making their decisions based on the total package of the candidates (academic results, interview performance, impression... etc), not by the colour of their skin. Whether you like it or not, selecting a cadet during an interview is a gamble. We have limited information and time to know a candidate fully. We have to go with "gut feeling" sometimes, and many times our gut tells us "no". And that's just the way it is.
I hope you don't harbour this racist feeling inside yourself. One day you may potentially become a commander, and you may have a SFO of a different race. I certainly hope you will treat him / her objectively with respect and not disadvantage him / her because he / she is different.