I’m not particularly worried about “food shortage” in places where food prices (including staples such as rice, corn, wheat and milk, for example) are not subsidized by a federal government. In places where relatively free markets operate, prices rise more or less gradually to inform consumers – and producers! – which items are in high demand / short supply. Producers use the information to determine when their marginally productive farms might become more profitable to improve in order to take advantage of higher prices. This tends to dampen huge spikes in price, because once the additional production occurs then price increases are mitigated.
Where the goods are subsidized and the shortage starts to occur while prices are kept artificially low and “stabilized for the masses”, then the first inklings of disaster occur when the government announces, seemingly out of the blue, that “prices for basic food items will be doubled” – or rationing occurs. In either case, shelves are stripped bare, production falls (since goods no longer make it to market, or a black market forms) and the crisis worsens.
Subsidies and other artificial mechanisms for “price stability” tend to corrupt the information channel that prices provide to market participants. It’s not magic; it’s basic communication.