A seasonal health advisory issued by the Ogle County Health Department in Illinois warned people about the dangers of unpasteurized apple cider, which has the potential to cause "serious illness or even death," if consumed, according to the U.S. Food and Drug Administration.

"Apple cider is a beverage made from fresh apples. It is typically a bit murky and golden-colored because it s unfiltered and unpasteurized," the department said in a Facebook post. "Most apple orchards don’t take the time to pasteurize because it is not required."

What does pasteurized mean?

Any juice, or cider that is not pasteurized, or "heat-treated," may contain harmful bacteria from the fresh-squeezed or raw fruits and vegetables used to make it, according to the FDA. That bacteria could lead to foodborne illness.

Who is at risk for consuming unpasteurized apple cider?

Children, older adults, pregnant women and people with weakened immune systems are more susceptible to the effects of food poisoning. These groups of people risk "serious illness or even death from drinking untreated juices," the FDA said.

All juices sold are not pasteurized

The FDA has received reports of foodborne illness outbreaks tied to the consumption of fruit and vegetable juice, and cider, but the agency notes that "most of the juice sold in the United States is pasteurized or is subject to non-heat processes to kill harmful bacteria."

All "untreated" juice products should be refrigerated and have warning label that says: "WARNING: This product has not been pasteurized and therefore may contain harmful bacteria that can cause serious illness in children, the elderly, and persons with weakened immune systems."