Roasting plays a pivotal role in nut processing. This step gives the nuts a unique aroma. And roasting even changes the texture and colour. The browning occurs by way of the so-called Maillard reaction. This involves protein and sugar components reacting to one another when exposed to heat. This results in the formation of brown pigments known as melanoidins. These are known for exerting an antioxidative effect and ensure that the nut has a longer shelf life.
Antioxidants protect the body against free radicals. There is, thus, a discussion as to whether the substances produced during roasting might even prevent the occurrence of cancer. In 2011, a study successfully demonstrated that the content of polyphenols exerting an antioxidative effect increases when cashew kernels are roasted – independent of the duration of roasting and the temperature. Additionally, the body is supposed to be able to assimilate magnesium and calcium from roasted nuts better than it can from raw nuts.
Furthermore: It is essential that peanuts are roasted prior to consumption. Classed, in botanical terms, as leguminous plants, they contain – just as beans or peas do – ingredients that are harmful to health, these however being destroyed upon heating.