Welcome back to our Mycotoxin Series!

Patulin wouldn’t be the first mycotoxin I’d typically introduce, but it has been in the news recently.  Patulin is produced by species of Penicillium, Aspergillus and Byssochlamys, which are filamentous fungi or “molds”.  Patulin can be found contaminating products like fruit, grains and cheese; however, apple juice is of most concern.  And let’s be real, it’s the bruised, damaged and misshapen apples that go into juice (blemish-free are reserved for fresh market’s picky consumers).  However, apples with rot (see below) should NOT go into juice or cider production due to patulin concerns.

apple with Penicillium expansum

Apple infested with Penicillium expansum, a patulin producer.
[NOTE: The blue-gray growth is the fungus. Patulin (waaaaay too small to be seen by the human eye!) is produced by the fungus and spreads into the rotten apple.]

Photo: Puel et al. 2010. Toxins (Basel). 2(4): 613–631.

In April 2013, Winn Dixie brand apple juice was voluntarily recalled due to patulin levels over 50 parts per billion (ppb).  In June 2013, researchers from the University of Granada reported that more than 50% of commercial apple juices tested contained >50 ppb patulin (50 ppb is the “limit” for patulin in both the US and EU).

Healthy apples

Healthy apples

Patulin in apple juice is of particular concern as this product is frequently served to young children.  In fact, some of the commercial juices tested in the aforementioned study were specifically produced and marketed to children. This toxin is a suspected carcinogen and symptoms of a patulin mycotoxicosis (poisoning) are gastro-intestinal inflammation and ulcers, weight loss, swelling, convulsions and impaired immune response (source).

While I’m not a medical doctor or veterinarian, eliminating the contaminated product from one’s diet often alleviates the symptoms.  However, acute mycotoxin poisonings are rare in the US (especially for humans).  Chronic exposure to low levels of mycotoxins is much more concerning and is difficult to study.  Hopefully, juice producers will step up their mycotoxin testing protocols to reduce the levels of patulin on the grocery shelves.