On a bright afternoon, when you stop in front of the nut section of the supermarket with a pack of smooth, shellless cashews in your hand, have you ever wondered: how did these delicious cashews "break out" from their hard shells and make their way to our tables safe and sound? Cashews occupy a place in the nut world with their unique sweetness and rich nutritional value, but their processing is little known, beguiling the complex and fascinating story behind it
The natural mysteries and structure of cashew nuts
Cashews, a nut with a unique shape, hide a wealth of nutrients and complex natural properties. Not only is it a favorite snack for many, but it is also a food with significant health benefits. However, the uniqueness of cashew nuts lies not only in its taste and nutritional value, but also in its unique way of growing and structure.
The environment in which cashew nuts are grown
Cashew trees are tropical evergreen trees native to Brazil and have since been widely planted in tropical regions around the world. The tree is adaptable to a wide range of soil types, but good cashews are usually sourced from well-drained, sandy soils. Cashew trees have a long ripening cycle and need to be patient to see ripe fruit.
The unique structure of cashew nuts
Cashew nuts have a peculiar structure, each one clings to a fleshy false fruit, the cashew apple, which is bright in color and sweet in taste, but it is usually not suitable for long-distance transportation, so it is less common outside of the country of origin of cashew nuts. The real cashew nut is located underneath the cashew apple and is protected by a hard shell. Not only is this shell strong, but it also contains a special chemical, cardanol, which is the main reason cashews need to be hulled and sold.
The Secret of Cashew Husks: Deadly Beauty
Despite the delicious and nutritious nature of cashew kernels, there are potential dangers hidden in their shells. The cardanol contained in cashew nut shells is a strong skin irritant that can cause skin inflammation and may even trigger severe allergic reactions in some people.
Chemical properties of cardanol
Cardanol (Urushiol) is an organic compound that is widely found in cashew nut shells. Skin that comes into contact with cardanol may experience erythema, swelling, itching, and even blisters. This reaction is not because cashews are toxic themselves, but because of an allergic reaction of the body's immune system to cardanol.
Treatment and removal of cardanol
Considering the potential risks of cardanol, the processing of cashews includes a series of steps designed to remove or neutralize the toxic components in the cashew nut shell. These steps include heat treatment to decompose or inactivate cardanol. In addition, cashew processing also needs to be carried out in special equipment to prevent the spread of cardanol and protect the safety of workers.
Although cardanol can cause adverse effects when it comes into contact with the skin, it has a unique use in some specific areas, such as the production of industrial paints. This seemingly paradoxical phenomenon illustrates the multifaceted nature of matter and the wisdom of humans in using them.