Value chains of be it food, machinery, etc. are demand driven and profit driven. Thus unless the "merchandise" of interest in this case for public nutrition benefit is efficient and cost-effective, the consumers that most need the said good will remain in the fringe of the market driven solution. Staple crops, biofortified or not, are part of cost-effective (though not optimally so) value chains of different scopes and quality. On the other hand, the value chains of the other elements of diets that constitute "diversified" dietaries are much more susceptible to losses due to physiological decay, seasonality of the fruits and vegetables and nuts, intensity of labor for production, particularly because undertakings such as homestead or community orchards (food gardens) do not typically benefit from economies of scale or links to market.
Dr. Erick Boy-Gallego