The present invention relates to a kind of heat sterilization compositions, include: the protein source of 5% to 20% amount by weight of the composition, and the protein source includes protein hydrolysate Wherein the protein source is handled in the continuation method using at least one endopeptidase, typically lasts for the time of finite length. Furthermore, the heat sterilization high protein composition that the present invention relates to a kind of with low viscosity and without bitter taste, endopeptidase comprising hydrolyzing temperature-sensitive protein source and at least one heat inactivation, the hydrolysis temperature-sensitive protein source have 20% to 50% protein degree indicated with NPN/TN. The invention further relates to a kind of continuation method for being used to prepare heat sterilization composition, the composition includes the protein source containing protein hydrolysate, and the described method comprises the following steps: (i) provides the aqueous solution of protein source (ii) continuous hydrolysis step is carried out, wherein handling the aqueous solution of the protein source by heating and continuing the time of 2 minutes to 20 minutes finite lengths at 40 DEG C to 90 DEG C using at least one endopeptidase (iii) make the endopeptidase heat inactivation. The invention further relates to a kind of viscosity for controlling heat sterilization high protein composition and the methods for preventing its bitter taste, the method includes providing the aqueous solution of the aqueous solution of protein source and the protein source described at least one endopeptidase continuous hydrolysis, then make the endopeptidase heat inactivation. Finally, heat sterilization composition is used to prepare the present invention relates to protein hydrolysate and/or the purposes of the viscosity for controlling liquid composition, the protein hydrolysate is prepared in continuation method as described herein by the time for handling finite le
