| Sesame paste?also called tahini?is a very polular semi-solid condiment paste,wildly used in hot pot,salad,pasta,dressing….However,there are many problems in sesame paste,such as simple varieties,poor taste,as well as oil separation during storage.These make it difficult to meet the consumers'demand for nutrition,healthy and stability.Therefore,developing new sesame pastes are quite essential.In this work,different varities of sesame were collected to compare the quality difference between black and white sesame paste to provided theoretical support for the next step.Then,the selected sesame was used as main raw material,peanut,syrup and stabilizers as additives to optimize the formulation of the mixed sesame paste.Finally,the quality difference between the mixed sesame paste and the commercially sesame paste were studied to give a reference for the application of the new product.Compared with white sesame paste,black sesame paste had obvious advantages in terms of the content of crude fat and the rate of colloidal stability.Black sesame paste was 6.20%lower than white one in crude fat.In the mean time,its'oil separation was 28.76%lower,which means black sesame paste was more stable.In terms of hardness,consistency,cohesiveness and viscosity,black sesame paste was higher than white sesame paste at the rate of 33.18,31.79,39.45 and 51.82,respectively.Nevertheless,Black sesame paste had obvious disadvantages in sensory quality and oxalic acid content.The oxalic acid content of black sesame sauce was 1.44 times than that of white sesame paste.As for sensory evaluation,the sensory score of black one was 65.4,which was significantly lower than white one with score of 72.6,especially in flavor,taste and overall acceptability,which was 15.10%,14.10%,and13.31%lower.As for color,particle size and rheological properties,there were some differences,but the effect on the quality of the sesame paste was not so significant.Due to the presence of melanin,there was significant difference between the two in color.In general,the particle size of black sesame paste was larger as well.Specifically,the D50 was 23.45%higher.Rheological analysis showed that all samples were non-Newtonian pseudo plastic fluids,exhibiting shear thinning phenomenon.But the area of thixotropic ring in black sesame paste was 99.10%higher than white sesame paste.In order to enhance the flavor of sesame paste,with sesame and peanut as the main raw materials,citric acid and syrup as additives,single factor,Box-Behnken test and principal component analysis were used to optimize the formulation of the blend sesame paste.The results showed that the optimal formulas for the blend sesame paste were peanut baking temperature of 140?,peanut baking time of 30 min,peanut butter of 26.6%,citric acid of0.04%,syrup content of 1.95%.The objective of this chapter was to evaluate the effectiveness of improving colloidal stability of the mixed sesame paste by incorporating palm oil,hydrogenated palm oil,wheat fiber,monoglyceride,sucrose stearate,sunflower wax and rice bran wax.It was found that sunflower wax had the lowest centrifugal oil yield,which was 77.27%lower than that of the control?with no stabilizer?,but it increased the hardness of the paste.Monoglyceride and sucrose stearate led to a reasonable effect,which could reduce the oil separation at the rate of37.32,31.67,without affecting taste,flavor,texture and fluidity of the paste.The microstructure analysis of the paste showed that the oil and protein in the mixed sesame paste were evenly distributed throughout the system.Besides,the link between protein and oil were loose.After adding the sunflower wax,liquid oil in the mixed sesame paste was trapped in crystal networks.The monoglyceride and sucrose stearate improved the stability of the paste by increasing the interaction between the oil and the protein.Through single factor and comprehensive experiments,the preferred composite stabilizers could be found,that were monoglyceride and sucrose stearate at 0.60%and 0.90%addition levels.At that time,the centrifugal oil yield of the mixed sesame paste was 5.43%,which was 63.48%lower than the control.The blend sesame paste,the commercially available white sesame paste,the commercially available black sesame paste and the self-made black sesame paste were subjected to quality analysis.It was observed that the content of crude fat,crude fiber,ash and oxalic acid were lesser in the mixed sesame paste,but crude protein,total sugar,essential amino acids,non-essential amino acids and total amino acids were the most.For example,the content of first limiting amino acid lysine was 0.66 g/100 g,which was 43.48%higher than the commercially available black sesame paste.The consistency,hardness,cohesiveness and viscosity were 239.00 g·s,38.09 g,11.38 g and 126.85 g·s in the mixed sesame paste.In the mean while,the mixed sesame paste had the best colloidal stability,with oil separation rate of5.50%.The oxidation induction time was 5.71 h,which was 7.25%lower than that of self-made black sesame paste,but 21.72%higher than the commercially available black sesame paste.Besides,the peroxide value and acid price were 0.06 g/100g,1.27 mg·g-1,which meets the standard of sesame paste.The maximum of 161 volatile substances were detected,with the highest content of pyrazines,alcohols and azoles in the formation of sesame paste flavor.As for pyrazines,the mixed sesame paste was higher than others at the rate of46.90%,28.84%,49.61%.The content of azoles was 3.45%,which was 8.41,3.14,2.04 times of the other three.The best sensory evaluation,especially in the flavor,taste,overall acceptance were observed in the mixed sesame paste. |
PDF Full Text Request