GB1012474A - Mixed fatty acid monoester compositions and their use in bakery mixes and other comestibles - Google Patents

Abstract

A monoglyceride emulsifying agent in which the monoglyceride does not readily convert to the stable but less active b -polymorphic crystalline form, consists of a partial ester composition comprising 35 to 60 mole per cent of at least one fatty acid mono-ester of glycerol and 40 to 65 mole per cent of at least one fatty acid mono-ester of 1,2-propanediol concurrently solidified therewith, the fatty acid moieties of the mono-esters consist essentially of saturated fatty acids having 16 to 20 carbon atoms and at least 75, preferably 90, moles per cent of the fatty acid moieties are the same in the two esters, and a substantial proportion of the mono-ester(s) of glycerol is in a normally unstable polymorphic crystalline form. The fatty acid moieties should have less than 5 mole per cent of unsaturated acid moieties. Preferred moieties are palmitoyl, stearoyl and mixtures thereof, and the fatty acid moieties of hydrogenated soybean oil and hydrogenated lard, but those derived from other hydrogenated fats and oils (specified) may be employed. The partial ester composition may be in the form of a powder or an aqueous dispersion containing 30-70% by weight of water, and may include a mixture of glycine and phosphoric acid as an anti-oxidant and sorbic acid as a mould inhibitor. Many other conventional antioxidants and mould inhibitors are mentioned. The composition may be incorporated into a baking mix such as a bread mix or a foam-type or triglyceride-containing cake mix, in a portion of 0.1-3.0% by weight based on the baking mix. The partial ester composition may be prepared by rapidly cooling a molten mixture of the esters by spray chilling to form a powder containing the mono-ester(s) of glycerol predominately in the a -polymorphic crystalline form. It is stated that the partial esters of 1,2-propanediol in the composition change from the a -polymorphic form to the b -prime (b 1)-polymorphic form shortly after being solidified or crystallized, in which form they exhibit substantial stability. The fatty acid partial esters of glycerol and 1,2-propanediol can be prepared separately and then admixed or, alternatively, such mixtures can be prepared by inter-esterifying a triglyceride having suitable fatty acid moieties, or free fatty acids, with glycerol and 1,2-propanediol and thereafter separating out a suitable partial ester composition. According to an example, 1160 grams fully hydrogenated lard flakes, 244 grams glycerol, 304 grams 1,2-propanediol and 1.7 grams strontium hydroxide were reacted for two hours at 250 DEG C. The reaction product was distilled in a molecular centrifugal still. The excess propylene glycol and glycerol were removed by stripping and a mixed 1,2 - propanediol mono - ester - glycerol mono-ester was distilled at between 90 DEG and 130 DEG C. and at a pressure of 20 microns of mercury. The distillate, amounting to 35% of the reaction product, had a composition of 0.43 moles of glycerol mono-ester and 0.57 moles of 1,2-propanediol mono-ester. A mixture consisting of 312 grams of the distillate, 0.02% glycine in a 4% glycerol solution and 0.02% phosphoric acid in a 33% glycerol solution was heated to 85 DEG C. and thereafter spray-dried to a powder readily dispersible in water at room temperature. Only 4% of the glycerol monoester was in the b -crystalline form, with the remainder in the a -crystalline form. Other examples disclose the preparation of glycerol monostearate, 1,2-propane-diol stearate and other mono-esters of 1,2-propanediol. The effects upon bread and cakes baked from doughs or cake mixes containing the partial ester composition is also given.