Salt Reduction Technology Based On ?-Carrageenan

High salt diet induced hypertension and other cardiovascular diseases have assumed a huge dietary crisis all over the globe.It is important for the food industries to reduce the salt in their processes.KCl has a salty taste similar to Na Cl and promotes the excretion of Na~+in the body.Therefore,using KCl as a substitute to salt can reduce the amount of Na Cl and is the most widely used salt reduction strategy.However,the bitterness of KCl affects the sensory acceptability and limits its application in food.?-car is a natural polysaccharide extracted from seaweed,which is often used as a coagulant,suspension agent,emulsifier and suspension agent in the food industry.It specifically binds to K~+,and changes from an irregular coil state to a helical state.This research mainly explores whether?-car can reduce the bitterness of KCl through the interaction between?-car and K~+.?-car was further applied to the development of low sodium salt and low sodium food.The effects of low sodium salt on the sodium intake in mice and the prevention of hypertension were also studied.(1)By means of sensory evaluation,electronic tongue and taste cell receptors,the effects of?-car on the bitterness of KCl systems with varying concentrations(0.4%KCl,0.6%KCl and 0.8%KCl)were studied,as well as the bitterness and saltiness of low sodium salt system(50%Na Cl+50%KCl).The results showed that adding?-car significantly reduced the metallic bitterness of KCl with sensory scores changing from 7-8 to 3-4,reaching a level of imperceptible intensity.In the low sodium system,the sensory score of bitterness was reduced to 1.5 under the mask of?-car and Na Cl,and it was difficult for the evaluator to perceive.In addition,with increasing?-car concentration,the saltiness of the low sodium salt system increased from 4.4 to 6.1,which was close to the saltiness of the pure Na Cl system,and achieved the reduction of sodium by 50%without changing the saltiness.The PLS results showed that the electronic tongue results were highly consistent with the sensory evaluation results.The taste cell receptors were successfully built and it showed that the masking effect of?-car on the bitterness of KCl was also applicable to the taste system of mice.(2)In order to explore the mechanism of?-car reducing the bitterness of KCl,the viscosities of these systems(0.4%KCl+?-car,0.6%KCl+?-car and 0.8%KCl+?-car)were determined,the specific binding characterization of?-car and K~+,the model of K~+release in vitro was established,and the comparative experiments of konjac and xanthan were conducted.The results revealed that the specific binding of?-car and K~+could slow down the release rate of K~+in the mouth,reduce the release amount of K~+,and the increase of viscosity prevents the transfer of K~+in the mouth,thus reducing the perception of K~+by taste receptors and the bitterness of KCl.(3)The low sodium salt containing Na Cl,KCl and?-car was prepared by oven drying method.The particle size,moisture content,density,element content,crystal structure and microstructure of the low sodium salt were also characterized.The results showed that the particle size of solid low sodium salt was about 100?m,and the content of sodium and potassium was 1:1.Most of the particles were mixtures of Na Cl,KCl and?-car after the interaction,and Na Cl and KCl existed in solid salt particles in the crystal form.Through sensory evaluation,50Na50K@15?-car was selected as the optimal formula for the model food.It was found that the low sodium salt containing?-car could reduce the bitterness of KCl in the model food,and has no effect on the acceptability of the food.The low sodium salt also improved the gel strength and texture of meat products,and improved its elasticity,masticability and juiciness.(4)By mice animal experiment,urine and feces of mice were collected through metabolic cage,the contents of Na,K and Ca released in urine of mice were detected to calculate the Na and K intake in mice.The blood of mice was collected and the content of catecholamine and creatinine in the blood of mice was measured to explore the effect of low sodium salt on Na and K intake,hypertension and kidney inflammation in mice.The results showed that when the content of Na and K in diet increased,the urine excretion of Na and K increased due to the feedback regulation mechanism.The addition of?-car promoted the excretion of Na and K.The intake of Na and K in mice is mainly related to the content of Na and K in the diet.At the same time,low sodium salt could also reduce the level of catecholamine and creatinine in the blood of mice,reduce the incidence of hypertension and relieve the pressure on the kidneys.