Watch Out... This Food Can Spontaneously Combust!
You think you know something and then you come across an article and your whole world is turned upside down!
Turns out, there's a lot of things you and I probably don't know about pistachios. For starters, the tiny, green, nutty snack is actually not a nut at all! Pistachios are technically drupes - as explained by The Guardian's blog post, a type of fruit in which the seed, or pit, is surrounded by a fleshy exterior, such as peaches, cherries, and mangoes. So, when you eat a pistachio, you're really eating the seed instead of the hardened outermost layer.
Another fact you may not know about pistachios: In some parts of the world pistachios are considered capable of heating the body and are consumed in the winter as a way to stay warm during the cold months. Some research from the Asia Pacific Journal of Clinical Nutrition suggests that this nutrition packed snack does cause the body to spend more energy therefore raising its own temperature.
The most bizarre thing you may not know about pistachios is that they can spontaneously combust!
While pistachios' high fat and protein content is what makes them a good snack in freezing temperatures, it's also what can make them flammable and under the right conditions, what can cause a barrel of them during transport to combust.
Pistachios have the tendency to generate heat on its own if packed in large quantities due to its high level of fat, 45% to 55%, and low water content. The fats in pistachios can break down through reactions with the air as the nut decomposes. Absorbing too much water from the environment can cause a pistachio's fatty acids to be broken down by moisture activated enzymes, a process known as enzymatic fat cleavage. As the fat decomposes, the chemical reaction produces carbon dioxide and, if repeated over and over, can generate quite a bit of heat.
This is how a large container of pistachios sitting in a dark, humid room can spontaneously combust and why it's crucial for them to be transported under the right conditions, low temperatures and a dry atmosphere!