Benders'dictionary of nutrition and food technology

288made. US legislation sets precise levels at which claims may bemade.Lowry reaction Sensitive technique for colorimetric determinationof protein using the Folin–Cioucalteau tungstate, molybdate,phosphate reagent, which reacts with tyrosine in proteins.Sensitivity 1 ng/mL, maximum absorbance 660 nm.lox American (originally Yiddish) name for smoked salmon; seealso lax.lozenges Shapes stamped out of mixture of icing sugar, glucosesyrup and gum arabic or gelatine with flavourings, then hardenedat 32–43°C.LRNI Lower reference nutrient intake; see reference intakes.LSM TM A low-sodium milk containing 50 mg/L; ordinary milkcontains 500 mg/L.lucerne See alfalfa.luciferase An enzyme that catalyses an ATP-dependent oxidationof a bioluminescent compound (luciferins of various types),leading to emission of visible light. Widely used as a reportergene in genetic engineering, and for assay of atp. Fireflyluciferase is EC 1.13.12.7, bacterial luciferase is EC 1.14.14.3.Luff–Schoorl method For determination of starch and sugars.Sugars are extracted using ethanol, then starch is hydrolysedusing hydrochloric acid and the resultant glucose is extractedafter neutralisation. Sugars are determined in the extracts afteroxidation using copper reagent, linked to the reduction ofpotassium iodide to iodine, and titration of iodine with sodiumthiosulphate.luganeghe Italian; pork sausage that is not twisted intolinks.lumichrome Product of ultraviolet irradiation of riboflavin(vitamin b 2 ) in neutral solution; some is formed in vivo on exposureto sunlight and is excreted in the urine. May also arise as aresult of intestinal bacterial metabolism of riboflavin. Formed inmilk on exposure to sunlight.See also lumiflavin; sunlight flavour.lumiflavin Product of ultraviolet irradiation of riboflavin (vitaminb 2 ) in alkaline solution; soluble in chloroform, and provides thebasis of a fluorimetric assay for the vitamin.See also lumichrome.luminacoids Japanese term, introduced 2003, to include alloligosaccharides, polyols, resistant starch, indigestible dextrins,resistant proteins and other compounds of plant or animalorigin that may undergo (bacterial) metabolism in the intestinallumen; a broader definition than either dietary fibre or nonstarchpolysaccharide.