Butternut squash seed

Butternut squash is a trailing vine whose pear-shaped fruit has pale tan skin and orange flesh. The seeds sit in a bulb-shaped cavity at the wide end of the fruit and are plump, flat, oval and cream to pale tan, with a thin, slightly fibrous husk.

They are smaller and thinner than the typical pumpkin seed. When roasted, they become crisp and golden with a toasty, mildly sweet flavour, and the soft husk is edible, unlike that of some other squash types.

Whole seeds are sold in the shell by specialty seed merchants, usually for planting, and most of the seeds eaten are home-roasted by cooks as a by-product of squash.

Cucurbita moschata, the species to which butternut squash belongs, was domesticated in Mesoamerica or northern South America several thousand years ago, with archaeological finds in Mexico and Colombia. The modern butternut was bred in Massachusetts in the 1940s by Charles Leggett, who developed it into a smooth-skinned, small-seeded, sweet-fleshed winter squash.

Today it is grown widely in the United States, Australia, South Africa, and Europe.

The genus Cucurbita is from the Latin word for gourd, and moschata means musky, a reference to the aroma of the plant.

Native peoples across the Americas cultivated squashes, often together with corn and beans, in the so-called three sisters planting. People ate the flesh, and the seeds as well, and squash seeds are among the most common archaeological plant finds in the Americas.

European explorers took squashes home to Europe, Africa and Asia, where they were adapted to local cooking. The butternut squash itself is a modern American variety, popularised through seed catalogues and farm stands from the 1940s and became widely popular for its keeping quality and sweet flavour. Australia and South Africa grow it in large quantities, often under the name butternut pumpkin.

Roasting squash seeds is a seasonal domestic tradition, particularly in North American autumn kitchens, along with pumpkin seeds at Halloween.

In Mexico and Central America, squash seeds are ground into sauces such as pipian.

Scoop out the seeds, rinse off the pulp, dry them and toss them with oil and salt or spices, then roast at a moderate heat until crisp. They can be sprinkled over soups, salads and roasted vegetables, or mixed into trail mix and granola.

Roasted and ground, they add body to sauces and spreads. The seeds can also be sprouted or planted to grow squash, although seed saved from hybrid squash may not come true.

In some countries, whole squash seeds are chewed as a snack, cracking the husks with the teeth.

Squash seeds in general supply unsaturated fats, protein, fibre, magnesium, zinc and other minerals, and some plant sterols. Research on pumpkin seeds, a close relative, links them with modest effects on urinary symptoms and blood lipids in small studies, but there is little research specifically on butternut seeds.

They are best viewed as a nutritious snack, and their calorie density suggests small portions.