Benders'dictionary of nutrition and food technology

187expands and rises in the water, the rise being measuredcontinuously.ferric ammonium citrate The form in which iron is sometimesadded to foods. Occurs as brown-red scales (16.5–18.5% iron)and as green scales (14.5–16% iron).ferritin The main iron storage protein in tissues; also found inserum, where the concentration reflects the total amount ofstorage iron in the body, and therefore permits assessment ofiron status over the range from deficiency, through normal tooverload. Although it provides the most sensitive index of irondepletion, its synthesis is also significantly reduced in responseto trauma and infection.See also acute phase proteins; transferrin receptor.ferrous gluconate iron salt of gluconic acid, used in iron supplementsand as a colouring agent in olives.ferrum redactum See iron, reduced.FFA Free fatty acids, see fatty acids, free.FIAF See fasting-induced adipocyte factor.fibre, crude The term given to indigestible part of foods, definedin the UK Fertiliser and Feedingstuffs Act of 1932 as the residueleft after successive extraction under closely specified conditionswith petroleum ether, 1.25% sulphuric acid and 1.25% sodiumhydroxide, minus ash. No relationship to dietary fibre (see fibre,dietary).fibre, dietary Material mostly derived from plant cell walls whichis not digested by human digestive enzymes but is partiallybroken down by intestinal bacteria to volatile fatty acids thatcan be used as a source of energy. A large proportion consists ofnon-starch polysaccharides; these include soluble fibre thatreduces levels of blood cholesterol and increases the viscosity ofthe intestinal contents and insoluble fibre (cellulose and cellwalls) that acts as a laxative. Earlier known as roughage or bulk.fibre, insoluble The part of dietary fibre (or non-starch polysaccharide)that is not soluble in water – cellulose, hemicellulosesand lignin. These increase the bulk of the intestinalcontents.fibre, soluble The plant gums and small oligosaccharides indietary fibre (or non-starch polysaccharide) that are solublein water, forming viscous gels.fibric acids A variety of analogues of clofibric acid (chlorophenoxyisobutyrate),including bezafibrate, clofibrate (the ethyl ester),fenofibrate and gemfibrozil (which is not halogenated), used intreatment of hyperlipidaemia.They lower vldl and ldl,and raisehdl, by stimulation of lipoprotein lipase (EC 3.1.1.34).fibrin See fibrinogen.