Prevention of anal leakage of polyorganosiloxane fluids used as fat substitutes in foods

Abstract: What is disclosed are food compositions which contain a polyorganosiloxane fluid as a fat substitute and an anti-anal leakage agent. The anti-anal leakage agents comprise C₁₂-C₂₄ essentially saturated fatty acids or edible, digestible sources thereof; non-degradable, water insoluble fibers of plant origin and silica.

Description: The present invention relates to a method of controlling the anal leakage of polyorganosiloxane fluids used as fat substitutes in food by adding an anti-anal leakage agent of the type disclosed hereinafter to the liquid siloxane or to foods containing the same. US-A-4,005,195 describes the use of anti-anal leakage agents in combination with liquid polyol fatty acid polyesters to provide pharmaceutical and food compositions for the treatment and or prevention of hypercholesterolemia while avoiding undesired anal leakage of the liquid polyesters. Examples of preferred polyols include erythritol, xylitol, sorbitol, glucose and sucrose, and examples of the fatty acids include hexaoleic, heptaoleic and octaoleic acids. The anti-anal leakage agent is preferably an edible C₁₂₋₂₄ saturated fatty acid or salt thereof, such as hydrogenated palm oil or natural or synthetic cocoa butter. US-A-4,461,782 describes low calorie baked products which comprise from 12 to 60% of a non-absorbable, non-digestible liquid polyol fatty acid polyester, from 25% to 85% of a mixture of microcrystalline cellulose and flour in a weight ratio of cellulose to flour of from 3:2 to 9:1, and, as an anti-anal leakage agent, from 10% to 50% by weight of the polyol polyester of a fatty acid having a melting point of 37°C or above, or of an ester of such fatty acid. Non-degradable polyorganosiloxane fluids can be substituted for fats in food compositions (EP-A-0,205,273 - Dow Corning Corporation). However, rats fed a diet containing about 6.5% by weight of polyorganosiloxane fluid exhibited undesirable anal leakage of the siloxane fluid. It has now been determined that this undesirable affect can be obviated by combining the polyorgano siloxane fluid with certain anti-anal leakage (AAL) agents. The types of AAL agents which can be used to overcome the above-described anal leakage problem are disclosed herein. According to the present invention there is provided a low calorie food composition comprising non-fat ingredients and fat ingredients wherein 0.1% by weight to 100% by weight of the total fat ingredients have been replaced by a fat substitute which is an edible, non-absorbable, non-digestible liquid siloxane polymer of the general formula (CH₃)₃SiO[(CH₃)₂SiO] b Si(CH₃)₃ wherein b has an average value of 25 to 500 and which fat substitute is characterised in that it contains an anti-anal leakage agent which is particulate silica having a surface area of at least 10m²/g, in an amount sufficient to prevent leakage of said liquid siloxane through the anal sphincter. The fat substitute generally comprises at least 10% to 50% by weight of particulate silica, the balance being liquid siloxane. The particulate silica preferably has a surface area of at least 80m²/g, more particularly a surface area of from 300m²/g to 400m²/g. For the purposes of this invention, the silicones can be described as polyorganosiloxanes which have an organic carbon content of at least fifteen (15) weight percent. Included within the scope of this invention are those siloxanes having organic substitutions wherein the organic substitution is linked to the silicon atom through a carbon/silicon bond. Such a limitation distinguishes the siloxanes useful in this invention from those wherein there is no organic substitution such as partial hydrolyzates and condensates of Si(OR)₄ wherein R is an alkyl radical. Further, this invention contemplates small amounts of-Si-O-C- bonded materials wherein the hydrolyzable by-products of such materials are not toxic to the human body, such as for example, ethanol, glycerol, sucrose and other organic sugars. In order to minimize the possibility of absorption of the siloxanes in the gastrointestinal tract, the siloxanes preferred for this invention should not contain significant amounts of material with molecular weights of less than 500 g/mole. By "significant", it is meant that there should be less than about 10 weight percent of such low molecular weights materials present in the composition, based on the total siloxane present. Preferred for this invention are siloxanes that are essentially free of low molecular weight materials as defined. Also, preferred for this invention is a polyorganosiloxane fluid of the general formula (CH₃)₃SiO[(CH₃)₂SiO] b Si(CH₃)₃ wherein b has an average value of 25 to 500. The siloxanes of this invention need not necessarily be truly soluble or miscible with the other components of the foods in which they are being used. They may be combined with the food either separately or in combination with the anti-anal leakage agent. The polyorganosiloxane fluid may be substituted in the food in a quantity of about 0.1 to 100 percent of the total food composition. The amount of siloxane used will depend on the amount of fat in the food composition. Types of food compositions within the scope of this invention include salad oils and salad dressings; dairy products such as cheese, cottage cheese, milk, ice cream, whipped cream and yogurt; baked goods such as cakes, pie crusts, cookies, bread, cereal, doughnuts and crackers; shortening substitutes; margarine; mayonnaise; peanut butter; and other food compositions where the fat component can be substituted with silicone oil. The class of materials which provide the anti-anal leakage effect described herein is particulate silica. To be effective at the concentrations claimed herein the particulate silica should have a surface area of greater than 10 m²/g as determined by the BET method. The BET method of measuring surface area is based on the adsorption of nitrogen at its boiling point under 1 atm pressure and measures both the interior as well as the total surface area of the particles. For the present invention, it is believed that the exterior surface area of the particle is the critical area. In cases where particles have considerable surface area interior to the particle, it is anticipated that one skilled in the art will appropriately adjust the weight of silica used to provide the requisite exterior surface area. Preferred is a silica with a surface area of at least 80 m²/g and most preferred is a silica with a surface are of about 300 m²/g to about 400 m²/g. The silica particles used as the AAL agent may be produced by any process adequate to produce the required surface area including grinding, milling, precipitation and vapor phase deposition. The AAL agent may be incorporated into the food composition either separately or by first being combined with the siloxane fluid. The AAL agent and fluid in combination or individually may be added to the food as appropriate during formulation, processing or preparation. It is preferred that the AAL agent be present in the final food composition at a concentration of at least about 10% by weight of the combined siloxane and AAL agent portions of the food composition. It is more preferred that the AAL agent be present in the final food composition at a concentration of at least about 20% by weight of the combined siloxane and AAL agent portions of the food composition. It is most preferred that the AAL agent is present at a concentration of about 20% to about 50% by weight of the combined siloxane and AAL agent portions of the food composition. These concentrations as specified reduce or abolish anal leakage of the siloxane fluid. Those skilled in the art will recognize that the disclosed AAL agent, that is, particulate silica if found normally in a food may allow adjustment of the actual AAL agent required to be added to the food. In addition, it may be recognized that diets containing the disclosed AAL agents could reduce the amount of AAL agent needed in a food composition to prevent anal leakage. The concentrations presented in the food compositions of this invention are those which reduce or prevent anal-leakage in the absence of other potential sources of AAL agent activity. The following non-limiting examples illustrate the composition of this invention. Example 1 As a control food composition a polyorganosiloxane fluid of the general formula (CH₃)₃SiO[(CH₃)₂SiO] b Si(CH₃)₃ wherein b had an average value of about 35 was blended into Purina Rat Chow 5012 Meal (Ralston Purina Company, St. Louis, Missouri) in the proportions of: 1500 g rat chow + 105 g siloxane fluid. A group of five adult rats weighting 275-350 g was allowed ad libitum access to this food composition as their exclusive diet for seven days. Animals were observed daily for evidence of anal leakage. Within 48 hours of access to this diet, all animals demonstrated slight to moderate anal leakage of the siloxane fluid. Example 2 To the food composition of Example 1 was added silica with an average surface area of about 300 m²/g to about 400 m²/g in the proportions of 1500 g rat chow + 105 g siloxane fluid + "n" g silica wherein n was 1, 3, 7, 15 or 30 g. Other experimental details where the same as in Example 1. A separate group of five animals each was used for each food composition tested. All test groups displayed a reduction in the incidence and severity of anal leakage in relation to the control group of Example 1. In general, as more silica was added to the diet the time to appearance of anal leakage increased and the number of animals displaying anal leakage decreased. Only the test group receiving the diet containing 30 g of silica was free of all signs of anal leakage of siloxane fluid. Example 3 To the food composition of Example 1 was added silica with a particle size of 32-63 micrometer in the proportions of: 1500 g rat chow + 105 g siloxane fluid + 30 g silica. Other experimental details were the same as given in Example 1. Silica of this particle size at the concentration tested effected a reduction in the severity and incidence of anal leakage of siloxane fluid in relation to the control group of Example 1. However, complete abatement of the anal leakage in all animals of the test group was not achieved.

Claims: A low calorie food composition comprising non-fat ingredients and fat ingredients wherein 0.1% by weight to 100% by weight of the total fat ingredients have been replaced by a fat substitute which is an edible, non-absorbable, non-digestible liquid siloxane polymer of the general formula (CH₃)₃SiO[(CH₃)₂SiO] b Si(CH₃)₃ wherein b has an average value of 25 to 500 and which fat substitute is characterised in that it contains an anti-anal leakage agent which is particulate silica having a surface area of at least 10m²/g, in an amount sufficient to prevent leakage of said liquid siloxane through the anal sphincter. A composition according to Claim 1, wherein said fat substitute comprises at least 10% to 50% by weight of particulate silica, the balance being liquid siloxane. A composition according to Claim 1, wherein the particulate silica has a surface area of at least 80m²/g. A composition according to Claim 3, wherein the particulate silica has a surface area of from 300m²/g to 400m²/g.

Inventors: RYAN JOHN WILLIAM, RYAN, JOHN WILLIAM
Applicants: DOW CORNING, DOW CORNING CORPORATION
Application year: 1989
Main classification: A23L1
IPC codes: A23C9, A61P1, A23C19, A21D2, A23C13, A23L1, A61K31, A23G9, A23D9