Study On The Preparation Of Diacylglycerol-based Margarine And Its Application In Bakery Foods

Margarine is a plastic fat product widely used in the field of baked goods and tea.However,the trans fatty acids and high proportion of saturated fatty acids in ordinary margarine tend to cause excessive accumulation of fat in the body,which increases the risk of obesity and cardiovascular disease.Diacylglycerol(DAG)oil is a new type of healthy structure lipid,which has physiological functions such as reducing body fat and improving lipid metabolism.However,there are few studies on the application of DAG oil replacing triacylglycerol(TAG)oil in margarine.In this study,diacylglycerol oil was used as the base oil to prepare diacylglycerol-based margarine,its physicochemical properties and flavor release characteristics were investigated,and it was applied to bakery foods such as bread and cakes.The main research contents and results are as follows:(1)Preparation and physicochemical properties of diacylglycerol-based margarine.Olive-based diacylglycerol-liquid fat(DAG-LF)and olive-based diacylglycerol-solid fat(DAG-SF)were used as the base oils to make a series of diacylglycerol-based margarines.The effect of DAG-LF/DAG-SF ratio on the physicochemical properties of margarines were investigated.The results showed that the content of saturated fatty acids in diacylglycerol-based margarines was 20～30%,and that of unsaturated fatty acids content was 70～80%.The melting point ranged from 22～46°C.The Solid fat content(SFC)curves of DAG-LF60 and DAG-LF65 showed that both of them had good stability,oil extraction resistance and mouth fusibility.DAG-LF50 and DAGLF60 had high intensity of the β’ form peaks,while the polymorph of DAG-LF65 was mainly β form.With the increase of DAG-SF content,the melting peak of margarines moved to the direction of medium temperature(30～40℃),and the melting crystallization behaviors changed greatly.The rheological properties of DAG-LF50 and DAG-LF60 showed that they had better stability against deformation,and DAG-LF65 had a softer and smoother taste.According to the physicochemical indexes,it’s determined that the oil with 50%,60% and 65% DAG-LF were suitable for the preparation of plastic fats such as margarine.(2)Study on the flavor release rule of diacylglycerol-based margarine.A simulation system of cream flavor was established to investigate the release rule of flavor substances in DAG-based margarine.The factors which influenced the release of flavor substances were also investigated.The results showed that the amount of flavor release decreased with the increase of the melting point of the base oil,and the amount of flavor release of TAG margarine with lower melting point was 1.9 times lower than that of DAG-LF50 margarine with higher melting point.Temperature significantly affected the release of flavor.With the increase of temperature,the release rate of flavor substances gradually increased.The flavor release of DAG and TAGbased margarines at 35℃ were 5.4 times and 7.2 times than that at-20℃,respectively.The compound types of flavor substances also had a significant effect on the flavor release.The acid compounds had the fastest release rate,followed by aldehydes,ketones and lactones.Acids,aldehydes,ketones,and lactones released 51%,43%,42%,and 26% respectively in DAG,and 90%,69%,62%,40% respectively in TAG.During the 10 h flavor release process,the release amount of flavor substances in DAG-based margarine reached the maximum at 4 h or 6 h,while in TAG,the release reached the peak at 2 h or 4 h.Compared with TAG-based products,the characteristic flavor compounds of milk flavor had a good sustained-release effect in DAG-based margarine.(3)Research on the application of diacylglycerol-based margarine in bakery foods.The diacylglycerol-based margarines were applied to breads,cakes and cookies to investigate the differences in properties between diacylglycerol-based margarine and commercial margarine in bakery products.The results showed that the gas holding property of DAG-LF60 and DAG-LF65 were similar to that of commercial margarine.There were no significant differences in the texture parameters of cakes and cookies prepared by DAG-LF60 and DAG-LF65 compared with commercial margarine.The texture parameters in bread applications(Elasticity,cohesion and recovery)were better than commercial margarine.Diacylglycerol-based margarine had the potential to replace ordinary plastic fat.The results of water migration during storage showed that DAG had a stronger binding force to water and could make the combination of water with protein and starch particles more tightly.DAG showed good flavor sustained release effect in bakery foods.