Benders'dictionary of nutrition and food technology

408refractometer Instrument to measure the refractive index.TheAbbé refractometer consists of two prisms between which thesubstance under examination (jam, fruit juice, sugar syrup, etc.)is spread, and light is reflected through the solution. The immersionrefractometer dips into the solution.refried beans See frijoles.refrigerants Cooling agents in refrigerators and freezers; originallyammonia or carbon dioxide were used, subsequentlyreplaced by chlorofluorocarbons (CFCs), freons and arctons.Because of the persistence of CFCs in the upper atmosphere,where they destroy the protective ozone layer, manufacture offully halogenated chlorofluorocarbons (CFCs) ceased in mostcountries in 1995, and they are being replaced by hydrofluorocarbons(HFCs) and hydrochlorofluorocarbons (HCFCs), sometimescollectively known as hydrofluoroalkanes (HFAs),although production of these compounds is to be phased out by2015–2020.See also heat pump.refrigeration, mechanical Equipment that evaporates and compressesa refrigerant in a continuous cycle, using the cooled air,cooled liquid or cooled surfaces to freeze foods.regional enteritis See crohn’s disease.Rehfuss tube A small diameter tube with a slotted metal tipfor removing samples of food from the stomach after a testmeal.See also ryle tube.Reichert–Meissl number Measure of the steam-volatile fattyacids in a lipid.See also kirschner number; polenske number; steam distillation.relative dose response test For vitamin A status. The increase incirculating retinol binding protein after an oral dose of vitaminA; greater in vitamin A deficient subjects because in the absenceof vitamin A reserves in the liver there is accumulation of theapo-protein.relative humidity See humidity.relative protein value A measure of protein quality.release agents Compounds used to lubricate surfaces that comeinto contact with food to prevent ingredients and finished productsfrom sticking to them, e.g. fatty acid amides, microcrystallinewaxes, petrolatums, starch, methyl cellulose.relish Culinary term for any spicy or piquant preparation used toenhance flavour of plain food.remove Obsolete term for the main course of dinner.Remyline TM fat replacer made from starch.