Plain Flour

Food · Grain · Food, Typed Supps

The refined default — and in many countries, quietly fortified.

Stage by stage

Milling (Endosperm separation): Bran and germ are removed, taking most fibre, magnesium and B vitamins with them.
Fortification (Regulated addition): Folic acid and thiamin are added back by mandate in Australia and the UK.
Gluten formation (With water and work): Glutenin and gliadin link into the elastic network that lets dough hold gas.
Digestion (Small intestine): The starch is hydrolysed rapidly, giving refined flour products a high glycaemic index.

Timing

No independent timing. What matters is the structure of what you bake — a dense sourdough and a soft white roll from the same flour behave very differently.

Time to effect

Immediate: Glycaemic response depends on the finished product.
Years: Fortification effects appear at population level, not individually.

Allergens

Contains: Gluten. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher. Depends on the product: Low-FODMAP.

Satiety

113 on the satiety index, where white bread is 100 — moderate. Modelled from the Holt et al. (1995) measurements.

Environmental footprint

1.6 kg CO2e and 648 litres of freshwater per kg, matched to "Wheat & rye" in Poore & Nemecek (2018), Science 360.

Cost band

Cheap — roughly £2 per kg, as a band midpoint rather than a price.

Key nutrients

Carbohydrate
Selenium
Manganese
Thiamin

Nutrition per 100g

Calories: 353
Protein: 10g
Carbohydrate: 73.2g
of which sugars: 1.9g
Fat: 1.3g
of which saturated: 0.2g
Fibre: 2.2g
Sodium: 3mg

Food vs. supplement

Fortified white flour delivers folic acid at population scale, which is a genuine public-health achievement — but it restores a specific list, not the fibre and mineral content milling removed.

Kitchen tip

Store wholemeal flour in the fridge or freezer — the germ’s oils go rancid within months at room temperature, which white flour’s do not.

Common myth

“Enriched flour is basically as good as wholemeal.” In reality: Enrichment adds back a defined list — typically folic acid, thiamin, sometimes iron. It does not add back the fibre, and it does not restore the full magnesium, zinc and vitamin E content the bran and germ carried. Useful public health, not a nutritional equivalence.