Quercus spp. nuts for human consumption

Acorns from the Quercus spp. trees can be found in copious amounts in the tropical and temperate regions and have a significant role in gastronomy, folk medicine and animal feed in these regions. Erstwhile, these nuts were an excellent food source during scarcity times, but nowadays acorns are largely perceived as animal feed and are far from being as widely used as other common nuts. Despite their large availability, only reduced quantities of acorns are curretly being used for human nutrition, so a new management approaches and usage of the produced wordwilde acorns would foment and contribute positively to the planet's sustainability. These nuts have an excelent nutritional profile and are a good source of bioactive compounds with numerous health benefits and relevant biological activities, which can contribute to health maintenance and well-being. In other to take advantage of these benefits, various technologies have been used to extract several compounds from different acorn species and several acorn-based functional products are under development, among which some are already found in today's market. The incorporation of acorn in food matrices has shown to improve food properties and nutritional profiles without affecting negatively the sensory characteristics and consumers' perception of these new foods. A brief description of the acorn history, production, and sustainability was done in this chapter. The core of this chapter involves the acorn transformation and use for human consumption. Thus, an extensive revision about the study and the use of acorn oils, flours, extracts, and beverages was done. The nutritional composition and the bioactive compounds naturally present in acorn were described, as well as the effect of their bioactivities on human health. Some green processing and extracting technologies were also discussed. Additionally, a section about tannins and acorn toxicity was also presented and discussed.