Kaifeng Lamb Intestine Soup

Lamb intestine soup appears in Kaifeng local food writings as having been sold in the city's markets since the Ming dynasty, though Henan provincial gazetteer records suggest it took its current form during the late Qing period; the dish's precise age is debated across sources. The social origin recounted across multiple sources is consistent: a poor slaughterhouse apprentice received lamb offal as wages in lieu of money, cleaned the intestines through the night, stuffed them with blood, and began selling the cooked result from a shoulder pole before dawn, charging one or two copper coins per bowl. This predawn offal economy sat within a much older tradition: during the Northern Song dynasty, when Kaifeng served as the imperial capital, the imperial household alone consumed tens of thousands of sheep annually according to Song administrative records, and the city's markets handled a massive volume of lamb carcasses. The intestine soup represents the lower rungs of that economy — the whole-animal logic of a community that wasted nothing. The name 双肠 (double intestine) specifically refers to using both the large and small intestine together, which is the defining characteristic separating it from single-intestine variants sold elsewhere in Henan.

The intestine casing is silky and tender with a gentle chew; the blood interior is firm but yielding, its mild iron note smoothed and rounded by the sesame paste. The lamb broth underneath is thin but intensely savory. Chili powder and coriander cut the richness, brightening the iron edge, and the flatbread that comes alongside soaks up the last of the broth.

The critical transformation is blood coagulation inside the natural casing. Lamb blood — a suspension of red blood cells and plasma proteins including fibrinogen and albumin — gels when heated to 70–80°C: fibrinogen undergoes irreversible thermal denaturation and converts to insoluble fibrin, forming a tight, cohesive matrix that holds the cylindrical shape of the intestine. Adding a small amount of cornstarch before filling stabilizes the gel further and prevents the blood curd from crumbling when sliced. The intestine wall itself is dense with collagen; during the hour-long gentle simmer it partially solubilizes into gelatin, which passes into the broth and transforms the casing from tough to silky. Sichuan pepper's terpene compounds, star anise's anethole, and ginger's gingerols combine to suppress skatole (3-甲基吲哚) and related indole compounds — the primary source of intestinal off-odor — allowing the clean lamb and blood flavors to come forward.