Yoshon (ישן)

Foods made from grain that took root before a certain point in the year — a stricter grain standard that mostly affects flour-based foods.

The Bible restricts 'new grain' (called chadash) — grain that took root after last year's Passover — until a certain date in spring. Grain that already passed that point is 'yashan' / 'yoshon' (literally 'old'), and is unrestricted. It applies to the five grains: wheat, barley, oats, spelt, and rye.

Products outside the Land of Israel.

Historically many people were lenient about new grain grown abroad; a growing number today specifically keep yoshon. Why: A major authority (the Bach) held this restriction doesn't apply to grain grown on non-Jewish-owned land; combined with uncertainty about exact planting dates, many relied on a lenient view outside Israel. As tracking improved, keeping yoshon became more practical.