Biotechnology for the functional improvement of cereal‐based materials enriched with PUFA and pigments

Abstract

Cereals as the major food supply are deficient in essential nutrients, such as PUFA and pigments. Biotechnological techniques based on solid state fermentation (SSF) and genetic engineering have been developed to naturally prepare functional cereals enriched with PUFAs and carotenoids. SSF represents a promising approach where the selected fungi (Zygomycetes) effectively utilize and transform raw cereal substrates to cereal‐based bioproducts containing high amounts of valuable PUFAs and carotenoids. Depending on the strain, types of cereal substrates, and cultivation conditions, a range of cereal‐based bioproducts enriched with PUFAs (up to 2.4% GLA, 4.2% AA, 2.1% dihomo‐gamma/linolenic acid, 2.3% eicosapentaenoic acid) and pigments (8.5 mg beta‐carotene/kg prefermented cereals) have been prepared. In addition, cereals (barley, wheat) consisting of gamma‐linolenic and stearidonic acids have been prepared by genetic transformation of the fungal fatty acid Δ6‐desaturase gene. Such functional prefermented cereal‐based bioproducts are characterized by the acceptable nutritive, functional, and flavor values, the improved antioxidant, radical‐scavenging, and thermal oxidation properties as well as the enhanced safety; therefore they may find applications in the food/feed fields.Practical applications: Cereals lack a number of nutrients, such as PUFAs and pigments which are essential for human well‐being due to their healthy, dietary, and functional properties. However, cereals could be considered as challenging sources of these compounds if they are naturally modified with the aim to contain PUFAs and pigments. Therefore the biotechnological preparation of cereals enriched with PUFAs and carotene pigments by fungal SSF has been developed. This natural technique is promising for the application of prefermented “bioproducts” in various fields and such cereal materials enriched with PUFAs and carotenoids might be considered as new types of inexpensive functional cereal‐based food and feed supplements.