Physical And Chemical Properties Of Dietary Fiber From Lemon Pomace And Its Application In Biscuit

Lemon peel is a by-product of lemon processing.The ratio is about 50% of lemon,most of them are taken as rubbish.It wastes the resource and pollutes the environment.Research has shown that,lemon peel is rich dietary fiber,it is a good source of dietary fiber,but the study on the preparation and physicochemical index relationship preparation technology is not deep enough.In this experiment,lemon peel was used as raw material to produce dietary fiber,the four main factors including pretreatment techniques,extraction way,drying methods and product size that influence the physical and chemical properties of dietary fiber were studied,the application of dietary fiber products in biscuits was also explored.The main conclusions are as follows:Solvent effect on physical and chemical properties of lemon dietary fiber: The raw material pretreatment techniques,drying methods and product size is unchanged,lemon peel is extracted in water at 90? for 90 minutes,the product has high water holding capacity and swelling capacity;lemon peel in 85% ethanol is extracted at room temperature for 40 minutes,the product has high oil holding capacity;lemon peel in 95% ethanol is extracted at room temperature for 90 minutes,the product has high the glucose dialysis retardation index;lemon peel in 95% ethanol is extracted at room temperature for 1 minute,the product has high the cation exchange capacity,and the losses of Vc content is minimal;lemon peel in water is extracted at 60? for 1 minute,get the highest total flavonoids and total phenol content of dietary fiber.Impact of processing conditions on physical and chemical properties of lemon dietary fiber: Lemon peel is made by blanching with hot water and cooling with flowing water?extracted in 95% ethanol at 60? for 90 minutes?freeze drying? product size of 80 meshes.the product has high water holding capacity and swelling capacity;extracted in 95%ethanol at room temperature for 1 minute?freeze drying? product size of 80 meshes.the product has high oil holding capacity;extracted In 95% ethanol at 60? for 90 min?freeze drying? product size of 80 meshes.the product has high glucose dialysis retardation index(GDRI);Drying at 60?? product size of 30 meshes,the product has high cation exchange capacity.Drying at 60?? product size of 80 meshes,the product has high total flavonoids and total phenol content.Freeze drying? product size of 80 meshes.the product has high Vc.To determine the optimum processing technique of lemon dietary fiber: Lemon peel is made by blanching with hot water and cooling with flowing water?extracted in same volume water at 90? for 90 minutes?freeze drying? product size of 80 meshes.the product hashigh whiteness,viscosity,water holding capacity,swelling capacity and oil holding capacity;Lemon peel is made by freeze drying? product size of 80 meshes.It has high Vc;Lemon peel extracted in 95% ethanol at 60? for 90 minutes? freeze drying? product size of 80 meshes.It has high whiteness,the glucose dialysis retardation index,total dietary fiber,soluble dietary fiber and insoluble dietary fiber;Lemon peel drying at 60?? product size of80 meshes.It has high cation exchange capacity,total flavonoids,total phenol content and insoluble dietary fiber.Application of dietary fiber in biscuits: Lemon peel is made by blanching with hot water and cooling with flowing water?extracted in same volume water at 90? for 90 minutes?freeze drying?product size of 80 meshes?the product of lemon dietary fiber,based on the weight of the flour,The optimum addition level in the crisp biscuits and tough biscuits were2% and 1.5%,respectively.The biscuit which we make owns a complete shape,golden yellow color,and smell well,According to difference in the amount of adding dietary fiber and preparation process of the type,the physical properties of biscuits are different: With the increasing in the amount of dietary fiber added,there are no obvious regularity in water content and alkalinity;water holding capacity showed an increasing trend;hardness,fracturability,and chewing index increase in the first stage and then decrease.The experiments show that: The optimum supplemental levels that add dietary fiber to crispy biscuit and tough biscuit is 2%,1.5%,at the same time,water holding capacity,hardness,fracturability and chewing index of the both biscuits are better.