In this video, we're going to begin our lesson on the process of desiccation, and how it is used as a physical method to control microbial growth. Although some microbes can survive for years without water, most microbes require water at a pretty constant rate in order to grow effectively. The process of desiccation is the process of drying out or removing moisture or water from something in order to prevent it from growing effectively. Generally, the process of desiccation results in the inhibition of microbial growth. Recall from our previous lesson videos when we talked about osmosis and tonicity that the addition of solutes such as salt, for example, can create what's known as a hypertonic environment. Hypertonic environments are capable of drawing out water from cells via osmosis in order to dehydrate those cells. The dehydration of those cells generally results in the inhibition of growth.
If we take a look at our image down below, we can get a better understanding of this process of desiccation, which again is like drying out. We have these images of the cactus and the sun to remind you of dried-out areas. Notice over here on the left, we're just showing you an image of desiccated soil, again to help you associate desiccation with drying out. Over here, we're showing you some meat that's actually being salted in order to create a hypertonic environment on the outside of the meat. Notice all of this salt that's on the outside of the meat, and this is called salt curing. It can help to preserve the meat, in order to delay microbial growth and inhibit microbial growth.
Essentially, what happens by adding the salt is creates a hypertonic environment, which, recall from our previous lesson videos, is an environment that has more solutes on the outside of the cells. Water, in terms of osmosis, always flows from hypotonic solutions towards hypertonic solutions. So, if the outside is hypertonic, water flows towards the outside of the cell via osmosis. When water leaves these cells, it desiccates or dries out the cells. Basically, what we get is what's called a, dried out or a crenated red blood cell here. Ultimately, this is also going to happen with microbes as well, and it will dry out and dehydrate those microbes and inhibit their growth. And really, that's the main idea behind the salting out here, is that it helps to inhibit and prevent microbial growth to preserve the meat.
This here concludes our brief introduction to desiccation as a physical means of controlling microbial growth, and we'll be able to get some practice applying these concepts and learn more about other physical methods of controlling microbial growth as we move forward in our course. So I'll see you in our next video.