Read about the Catholic blessing of the grapes. It is a Catholic tradition to have a priest bless grapes, preserve them, and then to eat them during times of famine, war, etc. Pious belief being this sacramental blessing will help sustain them spiritually. And possibly as a miraculous food.
The Church has not forbidden one particular blessings of the grapes devotion originating from a Marian mystic from Italy, named Moma Rose. It’s basically the same idea, but Mary in that apparition, it is permitted to believe, gave instructions what prayers to say before putting them in jars of brandy. The pious belief being one blessed grape would sustain you one 24 hour day during a disaster with no food.
We ourselves bought a big bunch of grapes, and per our local trad priest, will be having him bless them tomorrow after the traditional Mass, and then later put them in the jars of brandy, following the prayers. Will post pics here. I encourage everyone to also have grapes blessed for what is coming, in addition to prepping. It’s a special devotion (and fun for kids), which at least imparts a special blessing during disasters when you piously eat a blessed grape, the Church encouraging the use of sacramentals, including blessed holy water, candles, blessed foods, etc.