It depends on a couple of factors:
1. How well was the body embalmed? I have been a funeral director for a long time, and I can tell you that not all bodies embalm equally well! Those we receive at the funeral home quickly after death usually embalm well, though it's no guarantee. The arteries and veins have not been obstructed by clotted blood, and the pressure from the embalming machine clears the vascular system more efficiently, replacing the blood with the proper amount of preservative solution to insure proper distribution throughout the body. The capillary beds can be better-saturated, as well. Variables such as disease and drugs (such as chemotherapeutic drugs), or even trauma, can impede the embalming process.
2. How much time will be passing between the embalming and the funeral? Often times embalming may do too good a job at preservation, and, in fact, it may dry the tissues to the point of dessication, if left too long unburied or un-cremated. The longest I was forced to keep a deceased in the funeral home after embalming was seven weeks. The family was out of the country and was unable to return until that long a time had passed. The embalming was done well, and would have proceeded without incident if the funeral services had been more timely. But since it was weeks vs. days I was dealing with, I saw, with each passing day, that the body was starting to dessicate due to such good distribution of the embalming fluid. The cartilaginous parts such as the ears and nose narrowed, and the tissue completely dried, leaving them brittle and discolored. It was quite a shocking transformation! I was forced to wax and use tissue building agents to compensate for the tissue-loss so his family could view him. Cosmetics also played a large part in the restoration, as well. The family was amazed at how good he looked after so much time had passed (little did they know of the hours I put into the gentleman's restoration, fretting and tweaking as each day passed, just to make him presentable).
Preferably, there is a median most funeral directors would like to have, in situations where there is a delay between death and visitation. We don't do "normal" in this business, often, however, so we work with each challenge as it comes along, all the time keeping in mind that there is a family out there who wants to say goodbye to their loved one.
