A promising solution to reduce meat production is to shift towards alternative sources of proteins, such as cereal grains and legumes (Smil, 2000; Aiking, 2011). Previous results in terms of creating anisotropic structures have already been obtained using calcium caseinate (Manski 2007; Grabowska et al., 2012) and blends of soy protein isolate and wheat gluten (Grabowska et al., 2014). In meat substitute research, it is important to consider not only their structure, but also their nutritional value. In case protein isolates are used as main ingredients in a meat substitute, it would be opportune to consider fortification with important nutrients, for instance iron, to turn meat substitutes into not only sustainable, but also healthy alternatives to consumers. However, iron is a transition metal which can promote lipid and protein reactions, and hence alter the nutritional and organoleptic characteristics of food products. A solution could be to encapsulate iron, such that it would not be able to exert its prooxidant activity within the meat analogues. Encapsulation has been described as an efficient technique to preserve nutrient content and to increase their bioavailability by allowing the release of nutrients in specific environments of the gastrointestinal tract (Kuang et al., 2010). Till now, the use and stability of iron microencapsulates in plant protein-based structured foods has not been studied. This project is a collaboration between two research groups: Food Process Engineering (Wageningen University) and Laboratório de Desenvolvimento de Alimentos para Fins Especiais e Educacionais (UFRJ/Brazil).
The aim of this project is to fortify structured plant-based products with encapsulated iron. In addition, the enrichment of meat analogues with vitamins such as cobalamin (vitamin B12) will be also considered. The ultimate aim is to produce plant protein-based anisotropic structures with excellent stability and nutritional quality.
Different encapsulation systems will be tested in order to obtain stable ferrous sulfate microencapsulates, leading to high bioaccessibility of iron and minimizing nutritional and sensorial degradations in structured plant-based products. For this purpose, spray dried microcapsules, liposomes and double emulsions will be considered. We will investigate their encapsulation efficiency (EE) and physical stability, not only after preparation but also after incorporation into plant protein-based matrices made in a shearing device, and over storage. The chemical stability of the developed meat analogues (e.g., protein oxidation) will also be studied. Finally, the effect of iron fortification on the nutritional quality of these structured plant protein-based products will be assessed.
This work is supported by CNPq (Brazil).