Study On Processing Technology Of Compound Konjac Vermicelli

The ultrasonic-hot water bath swelling process was used to make compoundvermicelli in this experiment, with konjac purified powder and soybean proteinisolated as raw materials, to solve problems of bad dispersion and poor quality.At thesame time, the water-keeping agent of calcium hydrogen phosphate was used toreduce the dehydration ratio of vermicelli.Specific test contents and conclusions wereshowed as follows:(1)The test used the method of two factor randomized experiment with theadditive proportion between konjac purified powder and soybean protein isolatedand the additive level of water volume in room temperature. Considered compoundvermicelli gel strength and mixed liquid swelling time, it was the conclusion that theadditive proportion between konjac purified powder and soy protein isolated was2:1(2.00g:1.00g), and the additive level of water volume was60ml.(2)The method of ultrasonic-hot water bath was used to swell konjac-soy proteinisolated mixed liquid. Based on single factor experiments, it found that mixed liquidswelling time was influenced by ultrasonic power, ultrasonic time and hot bathtemperature, but had nothing to do with ultrasonic temperature.(3)Based on single factor experimenst, the five level four factor of quadraticorthogonal rotating combination experimental design was used to optimize theultrasonic-hot water bath swelling process, and established mathematical regressionmodel, which built relationships of vermicelli gel strength and ultrasonic power,ultrasonic time,ultrasonic temperature and hot water bath temperature. With the helpof anova analysis, the influence order was ultrasonic time> ultrasonic power>ultrasonic temperature> hot water bath temperature. From the theory and practicalconsiderations, it was the best choice that ultrasonic power70W, ultrasonic time4.2min, ultrasonic temperature52.4℃and hot water bath temperature44.6℃for theultrasonic-hot water bath swelling process.(4)The compound vermicelli made by the ultrasonic-hot water bath swellingprocess, which was compared comprehensively to those that made by the room temperature swelling process, the hot water bath swelling process and the ultrasonicswelling process on texture characteristics, vermicelli basic quality characteristics andsensory characteristics. The results indicated that compound vermicelli made byultrasonic-hot water bath swelling methoud were improved on the characteristics ofhardness, viscosity, chewiness, breaking rate, whiteness and sensory obviously.However, compared with the other three swelling methods,there were no significantdifference on characteristics of elasticity, conherency and cooking loss,but the highestdehydration ratio was obtained.(5)NaCl and urea were respectively added to compound vermicelli made by fourkinds of swelling methods to study the influence on compound vermicelli gel strength.The results showed that the vermicelli gel strength decreased gently when added NaCl,and decreased sharply with the addition of urea, what's more, the latter vermicelli gelstrength obviously lower than the former one on even ground. It could infer thatelectrostatic interaction and the hydrogen bonding interaction in konjac-soybeanprotein isolated system were inhanced in some degree respecticely, with the methodof hot tub swelling,ultrasonic swelling and ultrasonic-hot water bath swelling, but tothe hydrogen bonding interaction primarily.(6)Based on the method of two factor randomized experiment, the test studiedthe influence of the addtion level of Ca(OH)₂and calcium hydrogen phosphate oncompound vermicelli gel strength and dehydration ration. The results showed that thebest addtive levels which were based on the additive amount of konjac purifiedpowder were2.75%Ca(OH)₂and10.00%calcium hydrogen phosphate.