Producers make Pistachio Kernel from all types of Pistachios. A quality factor for kernels is their sizes. The more the color of the kernel`s second skin is violet and sharp the more it is popular among users. Higher the level of fat in pistachio kernels the tastier it is. Another interesting fact about pistachios without shell is that as the kernel size grows the color of kernel tends to more yellow-ish. So, if the kernel is premature its color is more green.