The above revelation of the Quran carried a scientific fact on the formation of milk in the cattle's, which could be unveiled only after thousand years of its descent.
The development achieved during the 12th C.E. by the Muslims give us glimpse of the scientific fact in the aforesaid verse. Imam Rhazes after mentioning the digestive, absorptive and cleaning process of the blood said, "...there are many veins between the livers and the udders, through those veins the blood passes to the udder, the udder is a fleshy white gland, when the blood comes there, God changes the blood into the milk."
The modern findings also confirm the Quran. From the stomach, the food after digestion passes into the belly i.e. in the intestines. The chemical reaction occurs in the intestine. Certain substances from the contents of the intestine (refuse) pass into the vessel of intestinal wall, and from there they pass into the blood stream. Some times by way of the liver or via complex system, they are absorbed in the blood and transported to all the organs of the body. Among them are the mammary glands, which produce milk.
Thus, there is no doubt that our milk comes from betwixt the refuse and the blood. The Prophet (sallallaho alaihi wasallem) was reciting a scientific fact on physiology when man was far away to reach to that part of the knowledge.
It is a damn mistake to think that the Prophet (sallallaho alaihi wasallem) had not reached to the depth of that knowledge. Allah did reveal him, opened his chest to the Quranic knowledge, and made him the exponent of His book.