| Di-acetyltartaric esters of monoglycerides, abbreviated DATEM, are anionic oil-in-water emulsifiers that are used throughout the world as improvers for bread-making and cake-making etc. Among the benefits found for this class of synthetic emulsifiers are excellent emulsifying ability, improvement of product volume, retardation of food staling and prolonging shelf life. The improver effect of the commercial product is well characterized, however, up to now no information is available about the influence of the acyl residue on the effect of DATEM in the application of the fried bread stick. To answer the question of which fatty acid residue is the most effective, In the present paper a systematic study to determine the influence of fatty acid chain length on the improver effect of DATEM is presented. Therefore, monoacylglycerols based on fatty acids with different chain lengths were synthesized and the corresponding DATEMs were prepared. The basic indicator of DATEM such as saponification value and acid values were determined, the characterization of major component of DATEMs was also performend by the determination of the molecular masses by Mass Spectrometry. at last The activity of synthesized DATEMs and commercial DATEM products was studied by means of rheological methods and a fried-bread-stick frying test. The effects of DATEMs on dough rheology and baking results are reported here.Firstly, Optimization of DATEMs Synthesis and basic indicator. DATEMs with fatty acids of chain lengths 8:0-20:0 were synthesized. Then some basic indicators of DATEMs such as saponification value and acid value were determined, and the result were reasonable. Mealwhile the DATEMs emulsion ability were determined, The DATEMs are exhibited in magnitude sequence: 14:0 DATEM, 12:0 DATEM, 18:0 DATEM, 8:0 DATEM, 20:0 DATEM, 10:0 DATEM.Secondly, Characterization of major components of DATEMs. 8:0-20:0DATEMs were titrated by lead acetate, and the precipitation happened, which indicated the synthesized DATEMs met experiment requirement.18:0DATEM was analysed by high performance chromatograph(HPLC),1-stearoyl-2,3-di-diacetyltartrylglycerin,1-stearoyl-3-diacetyltartrylglycerin,1-stearoyl-2-acety-l-3-diacetyltartrylglycerin and monoacylglycerol were identified. A commercial DATEM sample and 18:0 DATEM were investigated by IR mearsurement, the results showed that there were same functional group in both product.. The molecular masses of the three major components of 18:0DATEM were determined by Mass Spectrometry, according to the possible components of DATEMs, these three componets were: 1-stearoyl-2,3-di-diacetyltartrylglycerin,1-stearoyl-3-diacetyltartrylglycerin,1-stearoyl-2-acetyl-3-diacetyltartrylglycerin. And the content of these three components were more than others, which could be deduced from the strong Mass Spectrometry peaks. The other DATEMs were also investigated by Mass Spectrometry . And the three major components of other DATEMs were also indentified by the molecular masses difference from 18:0 DATEM. Then the related basic indicators of DATEMs such as saponification value and acid values were determined by some experimentations. Through these experimentation mearsurement, the final DATEMs were up to grade. Thirdly, Effect of DATEMs on dough Rheology. Dough rheology was tested by extensograph and farinograph measurements after addition of synthesized DATEMs. The effect of 14:0DATEM, 16:0DATEM, 18:0DATEM and 20:0DATEM on dougn extensograph were obvious. However only a slight effect of DATEMs on dough water absorption was observed. To study the Effect of DATEMs on dough Rheology, the frequency and temperature scanning rheology test were also carried out, the effect of DATEMs on elastic mldulus and viscous modulus were similar. Because of the diffirent interaction between DATEMs and dough componts, some DATEMs endowed the dough with high modulus, the others decrease the dough modulus.Fourthly, application of DATEMs in fried bread stick. Variation of the acyl residue from 8:0 to 20:0 showed that palmitic acid (16:0) had the best effect on the frying activity of DATEMs (volume rate increased by 58.6%, the oil rate increased by 0.7%). With the factors—orthogonal experiment, the optimization of fried bread stick bulking agent without aluminum is discovered. The ingredients based on the flour were as follows: 2.0%, sodium Bicarboate; 0.3%, 16:0DATEM; 2.6%, potassium bitartrate; 2.4%, calcium biphosphot. The results indicated that the bulking agent without aluminum can take the place of the traditional alum in the application of fried bread stick.
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