Could you please develop on how we should understand and put into the right context some racist statements of Srila Prabhupada.

I understand your concern. Here are some of my thoughts:

1. Prabhupada lived most of his life in a world which regarded racism as being the moral equivalent of nationalism. Just as people feel they are morally justified in supporting and preferring their own families over other families, or their communities and countries over other communities and countries, or indeed just as there are groups that support women and criticize men, or vice versa, similarly before Hitler’s atrocities, people all over the world supported and preferred their race over others. This was true not only in the West, but in Japan, India and so many other regions. After WWII and Hitler, and after the Civil Rights movement, racism became perhaps the single most sensitive moral issue in the West. India is a different world, with a different history, and Indians of Prabhupada’s generation never really learned post war Western sensitivities to race.
2. Prabhupada sometimes made bold statements, but in practice, in his life, he acted as a perfect, liberal gentlemen. In the early days of ISKCON, Prabhupada personally arranged interracial, black-white, marriages, placed black disciples in high positions, and treated everyone equally. In America, even among liberals, it is common to tell race and ethnic jokes. Because of the often oppressive political correctness movements, people let off steam in this way. I would take Prabhupada’s comments in that spirit, rather than as grave declarations of his deep feelings on a subject.