Influence of environmental and genetic factors on food protein quality: current knowledge and future directions

Dietary protein quality is commonly defined by the bioavailability of essential amino acids, a function of amino acid composition and protein digestibility. This review assesses the potential for manipulation of amino acid composition in organisms, for improving protein quality in nutrition. Animal protein is generally regarded as higher quality than plant protein, but it is also relatively resistant to change. Plant protein quality appears more susceptible to genetic and environmental influence with seed storage protein a potentially promising target, subject to GMO regulatory limitations. There is increasing interest in alternative dietary-protein sources including insects and fungi or other microorganisms. Each may be manipulated through environment or diet. Microorganisms also enable assessment of impacts on protein quality of biochemical-pathway manipulation or tailored growth regimes. We conclude that such approaches offer the greatest potential for manipulation. These means could help in producing protein of sufficient quantity and quality to meet future demand.