Benders'dictionary of nutrition and food technology

171The Rubner conversion factors for metabolic energy yield are:protein 17 kJ (4.1 kcal); fat 39 kJ (9.3 kcal); carbohydrate 17 kJ(4.1 kcal)/g.The Atwater factors also allow for losses in digestionand incomplete oxidation of the nitrogen of proteins: protein16.8 kJ (4 kcal); fat 37.8 kJ (9 kcal); carbohydrate 16.8 kJ(4 kcal)/g.The following factors are generally used: carbohydrate 17 kJ(4 kcal); fat 38 kJ (9 kcal); carbohydrate (as monosaccharides)17 kJ (4 kcal); alcohol 29 kJ (7 kcal); sugar alcohols 10 kJ (2.4kcal); organic acids 13 kJ (3 kcal)/g.energy drinks Beverages containing glucose, vitamins, minerals,herb extracts and caffeine, and sometimes other ingredients,claimed to provide energy and to promote alertness andwell-being. Some now contain artificial sweeteners instead ofglucose, so negating the claims to be a source of (metabolisable)energy.energy expenditure The total energy cost of maintaining constantconditions in the body, i.e. homeostasis (basal metabolic rate,BMR) plus the energy cost of physical activities. The averagetotal energy expenditure in western countries is about 1.4 ×BMR; a desirable level of physical activity is 1.7 × BMR.energy, kinetic Energy due to the motion of an object.energy, potential Energy due to the position of an object.energy requirements Energy requirements are calculated fromestimated basal metabolic rate and physical activity. Averageenergy requirements for adults are 8 MJ (1900 kcal)/day forwomen and 10 MJ (2400 kcal)/day for men, but obviously varywidely with physical activity.energy-rich bonds An outdated and chemically incorrect conceptin energy metabolism, which suggested that the bond betweenADP and phosphate in atp, and between creatine and phosphatein creatine phosphate, which have a high chemical freeenergy of hydrolysis, somehow differ from ‘ordinary’ chemicalbonds.enfleurage A method of extracting essential oils from flowersby placing them on glass trays covered with purified lard orother fat, which eventually becomes saturated with the oil.enocianina Desugared grape extract used to colour fruit flavours.Prepared by acid extraction of the skins of black grapes; it is bluein neutral conditions and red in acid.eNose TM An array of sensors attached to a gas chromatographsimulating the human olfactory response, used to profile flavours– an ‘electronic nose’.See also znose.