Since Hongzhi did not pursue the matter further, Qi Younian certainly wouldn't volunteer information about adding salt to ice. Adding salt to ice is the key to successfully transferring cold to the Ice Cream. Whether this secret could be kept safe if told to Prince Yu was Prince Yu's responsibility. If the key was revealed to Hongzhi at this time, it wasn't that Qi Younian didn't trust him, but that Hongzhi's assurance ultimately wasn't as authoritative as that of Prince Yu.
"Would the young master like to know the ingredients required for making Ice Cream?" Qi Younian changed the subject, discussing the composition of ingredients for Ice Cream.
Hongzhi quickly waved his hands, "No need, Sixth Master only asked me whether Ice Cream could be made during winter." Having said this, he bowed to Qi Younian, "Old Sir, I must take my leave now, Sixth Master is waiting for my response."
"Why the hurry, young brother? Why not sit down for a tea and some snacks before you go?"