Energy use in flour production

Abstract

AbstractEnergy use at three UK flour mills was studied. The primary energy required to provide the fuel and power used in milling averaged 1.16 GJ t−1 flour. Electricity accounted for approximately 80% of this value and was the sole energy source used directly in the milling process. Electricity consumption per tonne of flour showed no significant variation between a soft grist and a hard grist. The total primary energy requirement for the milling and transport of flour delivered in bulk was 1.43 GJ t−1 compared with 1.88 GJ t−1 for flour packed in 32‐kg bags, where transport and the provision of packaging material require additional energy use. Primary energy use in wheat growing was evaluated for Canada, USA, France and the UK but did not show marked differences, at about 4.4 GJ t−1 wheat. The primary energy requirement for fuel used in transporting wheat to UK flour mills was estimated to range from 1.46 GJ t−1 of Canadian wheat to 0.08 GJ t−1 of home grown wheat. In order to make available at a UK bakery flour milled from a grist of 30% Canadian, 40% French and 30% home grown wheat, the total primary energy requirement (including wheat growing, milling, transport of wheat and flour) was 6.41 GJ t−1 flour. However, flour production results in a nett production of food energy.