The present invention relates to an improved bio availability of protein/amino acids in palm kernel cake (PKC) by reduction in expeller processing temperature and/or time and/or force of palm kernels during palm kernel oil extraction. After expelling the palm kernel cake is upgraded by enzymatic hydrolysis and fermentation. The invention relates to methods for production of the up graded PKC and the upgraded PKC as such. The upgraded PKC can be used as an animal feed e.g. for feeding mono gastric animals.
