| 摘要 |
An adhesive composition comprises starch and at least 0.1% by weight based on the starch of a sodium, potassium, calcium or magnesium salt of a monoalkyl fumarate or maleate cotaining from 14 to 18 carbon atoms in the alkyl group, e.g. stearyl, cetyl or tetradecyl. A proportion of 1.6 g. of one of the specified fumarates and maleates, for example sodium monostearyl fumarate, dissolved in a minimum amount of hot water, was added to an 8% w./w. aqueous dispersion of unmodified corn (maize) starch that had been heated to 95 DEG C. for twenty minutes and the resulting starch paste was then heated at 95 DEG C. for an additional ten minutes; concentration of 0.1% and 2% of the fumarate or maleate, based on the weight of starch, were employed. The pastes produced were allowed to cool to room temperature and used to glue together two strips of paper. The pastes remained smooth and uniform upon prolonged storage (Examples 44 to 47).ALSO:The invention comprises sodium monostearyl fumarate, calcium monostearyl fumarate, sodium monostearyl maleate and sodium monocetyl fumarate. These and other sodium, potassium, calcium and magnesium salts of mono-C14 to C18-alkyl esters of fumaric and maleic acids may be prepared by treating maleic anhydride with an equivalent amount of the desired C14 to C18 alkanol and reaction of the monoester of maleic acid so formed in conventional manner to form the required maleic acid monoester salt, which salt can be isomerized to the corresponding fumaric acid monoester salt by standard catalytic methods. Alternatively, the maleic acid monoester itself may be isomerized to the corresponding fumaric acid monoester and the required salt prepared therefrom. In a further preparation the appropriate diacid can be treated with at least a dimolar amount of the C14 to C18 alkanol to form the diester, which diester is then reacted with an equivalent amount of aqueous sodium, potassium, or calcium hydroxide. Calcium and magnesium salts of the monoesters can also be prepared from the corresponding sodium or potassium salt by metathetical reaction.ALSO:A composition comprises starch and at least 0.1% by weight based on the starch of a sodium, potassium, calcium or magnesium salt of a monoalkyl fumarate or maleate containing 14 to 18 carbon atoms in the alkyl group as exemplified by stearyl, cetyl and tetradecyl. Starch pastes containing the ester-salts are stabilized with respect to viscosity and uniformity, particularly at elevated temperatures, and gelation and retrogradation are inhibited. Such compositions may be employed in starch manufacture generally, and in the production of cereal preparations and starch-containing foods including dehydrated creamed soups, pie fillings, dessert puddings, jellies and confections. Proportions in the range 0.1-4.0% of the fumarate or maleate, based on the weight of starch, are usually employed. When included in dough formulations, they act as a firmness retarder in the baked bread or cake produced, as described in considerable detail in Examples 10 to 22 and 42; the fumarate or maleate may be dry-blended with the flour used for the dough. When a paste of starch derived from maize, wheat, rice, oats or barley together with 2%, based on starch weight, of sodium monostearyl fumarate (or other of the specified fumarates and maleates) in a dry admixture is boiled, the fluid material obtained, having the consistency of unbeaten egg white, exhibits almost no surface skin on top and even after boiling for ten minutes still does not form a gel (Examples 23 to 25). Macaroni noodles and spaghetti are much firmer and less sticky after cooking, when one of the fumarates or maleates is included in the formulation with the milk component (Examples 26 and 27). Rice coated with one of the fumarates or maleates is fluffier, drier and less sticky after cooking than ordinary rice; the longer grain rice varieties require less of the ester-salt than the shorter grain rice (Examples 28 and 29). The fumarates and maleates when blended with pearl barley retard pasting and development of surface skin during cooking (Example 30). A wheaten oatmeal or farina preparation containing one of the fumarates or maleates, when heated slowly to the boil and then cooked at that point for seven minutes produces larger granules which are lighter in appearance, less pasty to the taste and contain no free water (Examples 31 and 32). When a 2% proportion, based on starch weight, of sodium monostearyl fumarate (or other of the fumarates and maleates) is added to a 5% paste of starch derived from maize, rice or tapioca, held at a temperature of 95 DEG C., the point of maximum viscosity, there is obtained upon cooling a fluid dispersion which pours readily. The amorphous material obtained by evaporating the material to dryness under reduced pressure, can be reconstituted to its original consistency by warming to 50 DEG C. There is a noticeable inhibition of granule swelling during heating when the fumarates or maleates are previously added to the starch paste at room temperature (Examples 33 to 35 and 40). The gelation of 10% wheat starch pastes is studied at three different levels of sodium monostearyl fumarate, based on starch weight. At the 2% level, the viscosity of the treated initial starch paste at room temperature does not increase even after holding at 95 DEG C. for more than an hour. At the 1% level no swelling of the starch granules occurs until a temperature of 95 DEG C. has been held for twenty minutes, whereafter the viscosity of the paste increases. At the 5% level the viscosity of the paste becomes stabilized during the holding period at 95 DEG C. although starch granule swelling is inhibited before this. When the fumarate is added in the same proportions to the wheat starch paste at the temperature of maximum viscosity, the viscosity is found to increase in every instance (Examples 36 to 38). The gluten obtained by a standard dough-washing procedure from a wheat flour dough containing 1% of sodium monostearyl fumarate (or other of the fumarates and maleates) based on flour weight, is found to be more cohesive and resists extension to a considerably greater degree (Examples 39 and 41). The addition of 0.25% based on the weight of dry solids, of sodium monostearyl fumarate to potato mash facilitates the drying of the mash to granule form by retarding the amount of starch gelation (Example 43). The fumarates and maleates impart antistaling properties to baked products such as bread, rolls, doughnuts, biscuits, cakes and pastries.ALSO:There is added to starch as a lubricant for preparing pharmaceutical tablets, at least 0.1% by weight based on the starch, of a sodium, potassium, calcium or magnesium salt of a monoalkyl fumarate or maleate containing 14 to 18 carbon atoms in the alkyl group e.g. stearyl, cetyl or tetradecyl.ALSO:A sizing composition for paper and textiles comprises starch and at least 0.1% by weight based on the starch of a sodium, potassium, calcium or magnesium salt of a monoalkyl fumarate or maleate containing from 14 to 18 carbon atoms in the alkyl group e.g. stearyl, cetyl or tetradecyl. A proportion of 1.6g of one of the specified fumarates and maleates, for example sodium monostearyl fumarate, dissolved in a minimum amount of hot water, was added to an 8% W/W aqueous dispersion of immodified corn(maize) starch that had been heated to 95 DEG C. for twenty minutes and the resulting starch paste was then heated at 95 DEG C. for an additional ten minutes; concentrations of 0.1% and 2% of the fumarate or maleate, based on the weight of the starch, were employed. A portion of each paste was then withdrawn and used to cast a film which was allowed to dry at 70 DEG F. and 50% relative humidity. The starch pastes were used to size cotton yarn at a temperature of 190 DEG F. (Examples 44 to 47). |
