the food composition according to the invention may be an oil - in - water or water - in - oil emulsion . suitable oil - in - water emulsions include reconstituted milk , ice creams , mayonnaises , salad dressings , etc . water - in - oil emulsions include savory or sweetened filling or spreading pastes , margarines , meat emulsions , coffee &# 34 ; creamers &# 34 ; or confectioner &# 39 ; s custard . an emulsion may be in liquid , paste - like ( semisolid ) or solid form , i . e . in the last case dried and reconstitutable with water , for example in the case of a whole milk or a coffee creamer . an emulsion of the type in question may be gelled , for example in the case of acidified milks , yoghurts and desserts . the composition may be a dispersion of solid particles in the fat , such as for example coating pastes and chocolate . the fats content of a composition is generally in the range from 10 to 90 % by weight . the caloric moderator may make up 10 to 100 % by weight of the lipid phase , depending on the caloric moderator effect which it is desired to obtain . it has in effect which it is desired to obtain . it has in effect been found that the rate of absorption of a mixture of the caloric moderator and a fat is inversely proportional to the content of the caloric moderator in the mixture . in certain applications , for example as frying oil , the caloric moderator may be used on its own or in admixture with an oil . in this particular application , the excellent stability of the caloric moderator to hydrolysis and to heat treatment represent a very significant advantage . the level of incorporation of the caloric moderator is advantageously from 10 to 90 % by weight of the lipid mixture for the lactic fats and vegetable oils commonly used . one particular application is the partial replacement of cocoa butter or lactic fats in chocolate or filling or coating pastes . in this case , the level of incorporation compatible with the physicochemical properties of cocoa butter is from 10 to 15 % by weight , based on the cocoa butter , in the case of chocolate or up to 100 % in the case of filling or coating pastes . the caloric moderator may be prepared in known manner by chemical esterification of the polyol with the fatty acid or fatty acid mixture in the absence of an organic solvent , this method having been applied to the re - esterification of fatty acids with glycerol described , for example , in fat . sci . technol . 89 , 480 - 485 . the esterification reaction takes place in a reactor equipped with a stirrer , with means for keeping the temperature at a value close to the reflux temperature of the mixture of reactants and with means for removing the water of reaction by distillation . the reaction is carried out in the presence of a catalyst , for example zinc chloride , with a slight excess of polyol over a period of 2 to 4 h at 150 ° to 170 ° c . a vacuum of 2 . 7 to 27 mb ( 2 to 20 mm hg ) is then applied and distillation is continued for 1 to 3 h . after cooling to ambient temperature , the mixture is taken up in a solvent , for example hexane , and the zinc chloride is separated by filtration . the product obtained may then be purified by chromatography , for example on alumina . alternatively , the mixture is directly subjected , i . e . without being taken up in a solvent , to refining without degumming , i . e . by neutralization , decoloration , evaporation of the solvent and , finally , deodorization . in a variant of the synthesis , the esterification may be carried out in a known manner by the enzymatic method using a non - specific lipase , for example of yeast . a lipase of candida cylindracea , for example , may thus be used . this is done by a batch process in which the fatty acids are dissolved in a hydrocarbon , for example n - heptane or n - hexane , for example in a concentration by weight of 2 to 10 %. the polyol is mixed with approximately 10 % water containing an excess of enzyme in relation to the fatty acids , for example approximately 3 parts by weight enzyme to 2 parts by weight fatty acid . the aqueous phase ( ph approx . 7 . 2 ) and organic phase are introduced with vigorous stirring at a temperature of 20 ° to 55 ° c . and preferably at a temperature of 40 ° to 45 ° c . the reaction -- in heterogeneous medium -- takes place at the interface between the two phases and is displaced towards the formation of ester because the ester passes into the organic phase as it is produced . in one preferred continuous variant of this enzymatic synthesis , the reactants may be introduced into an enzyme immobilized , for example , on resin , silica or cloth in a reactor which enables a smaller quantity of enzyme to be used . the caloric moderator may advantageously be protected against oxidation by incorporation of an antioxidant , preferably a liposoluble antioxidant , for example a tocopherol or ascorbyl palmitate . finally , the present invention relates to a process for the production of a hypocaloric food , characterized in that a caloric moderator of the type defined above is incorporated in the food . in one particular application intended for the production of a fried food , for example potatoes , noodles , meat or breaded fish , a vegetable or fruit coated with a frying mix , the process is characterized in that the food is fried in the presence of a caloric moderator of the type defined above . the invention is illustrated by the following examples in which parts and percentages are by weight , unless otherwise stated . ______________________________________ % ______________________________________oleic acid 70stearic acid 10palmitic acid 10linoleic acid 5myristic , palmitoleic and arachic acids 5______________________________________ are mixed with 0 . 56 g zinc chloride in a reactor equipped with a stirrer and the mixture is heated with stirring to 160 ° c . the reactor is purged with nitrogen during the heating phase . 9 g 2 , 3 - butanediol in racemate form are then gradually added with stirring . the reactor is provided with a descending condenser kept at 15 ° c . by circulation of cold water . after a reaction time of 3 h at 160 ° c ., a vacuum of 5 mb is applied and the water is continuously eliminated with the remaining 2 , 3 - butanediol by evaporation over a period of 2 h . after purification of the liquid obtained by passage of a 1 : 1 solution in hexane over a column of aluminium oxide , a purified ester containing approximately 0 . 2 % free fatty acids is collected : refractive index 1 . 4635 at 20 ° c ., viscosity 49 mpa . s at 20 ° c . and density 0 . 895 ( g / cm 3 ) at 22 . 4 ° c . the purified product , which is pale yellow in colour , is odourless and behaves like a neutral vegetable oil , for example sunflower oil , from the point of view of its physical properties , particularly its stability to heat . 2 mol of the fatty acid mixture used in example 1 are heated with 1 % zinc chloride with stirring at 160 ° c . and 1 . 15 mol 2 , 3 - butanediol ( racemate ) are gradually added . the mixture is left to react at that temperature for 3 h , during which the water formed is continuously removed in the form of steam . a vacuum of 13 mb ( 10 mm hg ) is then applied and the reaction is continued under these conditions for 2 h . after cooling to ambient temperature , the zinc chloride is separated by filtration . after neutralization , decoloration and , finally , deodorization , a pale yellow , odourless and tasteless product is collected , its physical properties being comparable with those of a neutral oil . the procedure is as in example 2 , 2 , 3 - butanediol ( racemate ) being reacted with the following mixture of fatty acids : ______________________________________ % ______________________________________ lauric acid 13 stearic acid 33 palmitic acid 23 oleic acid 28 other acids 3______________________________________ it behaves similarly to cocoa butter from the point of view of its melting characteristics , as can be seen by studying the solid fat index ( sfi ) obtained by determination of the melting curve . thus , the sfi -- the percentage of solid &# 34 ; fat &# 34 ; existing in the &# 34 ; fatty substance &# 34 ; partially melted at a given temperature , determined by pulsed nmr ( nuclear magnetic resonance of the proton ), cf . i . u . p . a . c ., 1st supplement , 1982 , method 2 . 323 -- is shown in the following table by comparison with that of cocoa butter : ______________________________________ temperature (° c . ) sfi (%) 5 10 20 30 37 40______________________________________product of example 2 73 68 63 48 12 5cocoa butter 85 82 73 40 8 0______________________________________ 4 . 1 study of the ingestion of a diet containing the caloric moderator in obese rats 9 male rats 8 weeks old are divided into two groups of 4 and 5 taken at random , but in such a way that the average initial weights in each group are equal . the two groups are fed at will on a standard diet in which 10 % of the diet is replaced by ( a ) cornseed oil and ( b ) the product of example 2 over a period of 35 days . the rats are weighed twice weekly on days 3 and 7 and their hair , their anus , their faeces and their behaviour are observed . the diet supplied and the remaining diet are weighted after each ingestion ( the diet eaten is obtained by subtraction ) and the ration is renewed at regular intervals , still using the same quantity . the cumulated ingestion diet per animal is then determined . after 5 weeks , the animals are killed , their blood is collected and the plasma is separated . the heart and liver are removed , washed and immediately frozen , the organs then being stored at - 40 ° c . pending analysis . the results relating to the development of the weights are shown in table 1 : table 1__________________________________________________________________________groupa b differ - average average average average ence in weight average cumulated weight average cumulated weight increase weight ingested increase weight ingested increaseday ( g ) ( g ) diet ( g ) ( g ) ( g ) diet ( g ) a - b ( g ) __________________________________________________________________________ 0 0 249 0 0 249 0 0 3 27 276 83 . 6 22 271 85 . 7 5 7 62 311 203 . 8 54 303 213 . 2 810 88 . 6 337 . 6 291 . 8 75 . 1 324 . 1 301 . 5 13 . 514 122 371 416 . 7 102 . 5 351 . 5 423 . 5 19 . 517 143 . 3 392 . 3 501 . 2 116 . 2 365 . 2 508 . 3 27 . 121 169 . 5 418 . 5 618 . 3 137 . 4 386 . 4 622 . 9 32 . 124 188 . 4 437 . 4 705 . 4 148 . 3 397 . 3 704 . 6 40 . 128 209 . 9 458 . 1 827 . 8 166 . 4 415 . 4 824 43 . 531 224 . 3 473 . 3 917 . 4 174 . 4 423 . 4 918 . 8 49 . 935 247 . 2 496 . 2 1033 . 6 191 . 6 440 . 6 1031 . 4 55 . 6__________________________________________________________________________ a distinct difference in weight increase is observed from the beginning of the regime between group a ( diet containing cornseed oil ) and group b ( diet containing the caloric moderator ), group a growing larger distinctly more quickly than group b . the diet of group b contained approximately 6 % digestible fats , including 17 % linoleic acid and 1 . 8 % α - linolenic acid . these values are standard for typical laboratory diets and are considered to be sufficient for avoiding lipid deficiencies in rats . the faster growth of group a continued throughout the experiment and resulted in a difference in the weight increase of 22 . 5 % between the two groups and in a total weight difference of 11 . 2 %. the energy difference between the two diets , based on metabolizable energy of 3 . 16 kcal / g for the standard diet , represents 24 % assuming that the calorie input of the caloric moderator is zero . this is in almost perfect accordance with the observed difference in weight increase of 22 . 5 %. this shows that the caloric moderator in group b is not metabolized and that its caloric contribution is substantially zero . so far as the taking of food is concerned , there is no significant difference between the quantities ingested in the two groups throughout the study . the slight difference observed represented 2 . 2 g for group b out of more than 1 , 000 g total average intake per animal , i . e . 0 . 2 %. that there is no preference for or rejection of either diet for organoleptic reasons and that the fact that the diet of group b has a lower caloric density does not lead the animals to eat more by way of compensation , but that the presence of the moderator gives them the same feeling of fullness as , for example , the cornseed oil of the diet of group a . these observations remained valid for the entire duration of the regime . there was no major change in the eating habits of the animals in the two groups . finally , no abnormal phenomenon was observed in any of the animals . the animals of the two groups had dry , non - greasy hair , a non - greasy anus and consistent stools with no sign of diarrhoea . the stools of group b were greasy , but hard . accordingly , it appeared that no disturbing effect on the intestinal transit could be attributed to the caloric regulator . analysis of the tissue lipids of the hearts and livers revealed no trace of unmodified diol ester accumulated in the organs . the two groups showed the presence of small quantities of the diol esters which are normally observed in the liver . 5 young female mice receiving a standard diet and water at will were fed with 20 ml of the product of example 1 per kg bodyweight by cramming in a single dose . the animals were weighed on days 1 , 2 , 3 , 4 , 5 , 8 , 12 and 15 . observation of the animals showed no toxicity , mortality or abnormal behaviour . the anal part of the animals became greasy 1 . 5 h after administration of the product , although this phenomenon did disappear after 24 h . the weight increase was approximately 10 % in 15 days . two formulations of the &# 34 ; mayonnaise &# 34 ; type ( oil in water ) having the compositions indicated in columns ( a ), ( b ) and ( c ) below are prepared . the products have comparable organoleptic characteristics , but very different caloric values ______________________________________ ( a ) ( b ) ( c ) ______________________________________sunflower oil 81 41 -- liquid 2 , 3 - butanediol ester -- 40 81of example 2egg yolk 5 5 5vinegar 4 4 4salt 1 . 5 1 . 5 1 . 5sugar 1 . 5 1 . 5 1 . 5flavourings 0 . 8 0 . 8 0 . 8water qsf 100 -- -- -- kcal / 100 g 780 422 53kj / 100 g 3 , 270 1 , 770 222______________________________________ salad dressings ( oil - in - water emulsions of which the aqueous phase contains vinegar ) are prepared , starch being used as thickener . the compositions shown in columns ( d ), ( e ) and ( f ) below illustrate the reduction in caloric value obtained by using the caloric moderator . ______________________________________ ( d ) ( e ) ( f ) ______________________________________sunflower oil 42 20 -- liquid 2 , 3 - butanediol ester -- 22 42of example 2egg yolk 5 5 5salt 4 4 4sugar 3 3 3starch 9 9 9vinegar 15 15 15spices 3 3 3water qsf 100 -- -- -- kcal / 100 g 473 274 94kj / 100 g 1 , 985 1 , 150 394______________________________________ the 2 , 3 - butanediol ester -- solid at ambient temperature -- of example 3 is mixed with cocoa butter and / or cocoa butter substitutes in the quantities shown below to produce chocolate or coatings having the same physical and organoleptic characteristics , but a reduced caloric content , for the chocolate compositions ( g ), ( h ) and ( i ) shown below : ______________________________________ ( g ) ( h ) ( i ) ______________________________________cocoa solids ( fats 55 %) 32 . 8 * 32 . 8 * 32 . 8 * sucrose 48 . 3 48 . 3 48 . 3cocoa butter 19 . 2 12 -- 2 , 3 - butanediol ester of -- 7 . 2 19 . 2example 3soya lecithin 0 . 3 0 . 3 0 . 3flavourings traces traces traceskcal / 100 g 560 495 387kj / 100 g 2 , 350 2 , 070 1 , 621______________________________________ * corresponds to 30 dry matter if , in composition i , the sucrose is replaced by a sugar ( palatinit ®, an acariogenic concentrated sweetener of reduced energy value consisting of a mixture of glucosyl sorbitol and glucosyl mannitol , supplying 50 % of the calories of the product ), the chocolate obtained has a caloric value of 190 kcal or 1215 kj / 100 g .
food compositions are prepared by incorporating in a food a diester or triester of fatty acids and an aliphatic c 4 - 5 diol or triol having secondary alcohol functions . fried foods may be prepared by frying the food in the presence of the diester or triester .