Benders'dictionary of nutrition and food technology

489The root has traditionally been used as a sedative and tranquilliser,with evidence of efficacy.valgus Any deformity that displaces the hand or foot away fromthe mid-line of the body; e.g. genu valgus is knock knees, as seenin rickets.See also varus.validity Of an assay, the extent to which a method measures whatit purports to measure.See also accuracy; precision; sensitivity; specificity.valine An essential amino acid, abbr Val (V), M r 117.1, pK a 2.29,9.74, codons GUNu; rarely, if ever, limiting in foods.valzin, valzol See dulcin.vanadium A mineral known to be essential to experimentalanimals, although sufficiently widespread for human dietary deficiencyto be unknown. Its precise function is unknown, althoughit acts as an activator of a number of enzymes.vanaspati Indian; purified hydrogenated vegetable oil; similar tomargarine and usually fortified with vitamins A and D. Alsoused to prepare ghee (vanaspati ghee).vanilla Extract of the vanilla bean, fruit of the tropical orchidAracus (or Vanilla) aromaticus and related species. Discoveredin Mexico in 1571 and could not be grown elsewhere, becausepollination could be effected only by a small Mexican bee, untilartificial pollination was introduced in 1820. Main growingregions now Madagascar and Tahiti.The major flavouring principle is vanillin (chemically methylprotocatechuic aldehyde), but other substances present aid theflavour. Ethyl vanillin is a synthetic substance which does notoccur in the vanilla bean; 3.5 times as strong in flavour, and morestable to store than vanillin, but does not have the true flavour.vanillin See vanilla.VaporPrint TM imaging A graphical representation of the flavourprofile obtained using a znose TM ‘electronic nose’.variety meat American name for offal.varus Any deformity that displaces the hand or foot towards themid-line of the body; e.g. genu varus is bow legs, as seen inrickets.See also valgus.vasoactive intestinal peptide (VIP) Protein secreted by thepancreas; over-secretion can cause severe diarrhoea.vasoconstriction Constriction of the blood vessels; the reverse ofvasodilatation.vasodilatation (vasodilation) Dilation of the blood vessels; thereverse of vasoconstriction. Caused by a rise in body temperature;serves to lose heat from the body.