The Changing Of Carbohydrate In The Za-chilli And Its Effect On The Edible Quality

Za-chilli,a fermented product by lactic acid bacteria in Chongqing,Sichuan,Guizhou,or minority living areas,is produced by the anaerobic fermentation of the mixture of broken fresh red chili and rice flour mainly.It can be cooked directly or used as a seasoning for cooking dishes.Its unique flavor is deeply loved by the craving consumers.In this study,corn,indica and waxy rice were used as experimental materials to study the changes in carbohydrate composition and physicochemical properties of starch and the possible mechanism was initially explored.1.Changes in General Ingredients during the Fermentation and it's Sensory EvaluationThe results of the determination of the basic ingredients of the of Za-chilli showed that the protein and fat content of three kinds of Za-chilli decreased significantly during the fermentation,but the ash content did not change significantly.The carotenoid and capsaicin content decreased significantly during the fermentation(p<0.05).The results of the carbohydrates composition showed that the total sugar content of three kinds of Za-chilli decreased significantly during fermentation(p<0.05).Starch,the main carbohydrate,was continuously decomposed and utilized during the fermentation with a significant decline(p<0.05).Dietary fiber,a type of important non-digestible carbohydrates in Za-chilli,showed a downward trend.Reducing sugars,soluble total sugars,crude polysaccharides,and oligosaccharides showed a trend of increasing first and then decreasing.It is related to the decomposition of starch and dietary fiber.During the fermentation process,the sensory quality of Za-chilli gradually increased with the progress of fermentation,reaching a peak on the 40 th day of fermentation and finally showing a downward trend.The color,texture,aroma,and taste of Za-chilli reached a good balance,the evaluation score reached the highest.The correlation analysis showed that the sensory evaluation of Za-chilli was coordinated by various sugars,starch and dietary fiber.2.Changes of Starch Properties and Their Effects on Edible QualityStarch is the most abundant carbohydrate in Za-chilli,and its change will have an important impact on the quality of the Za-chilli.In this experiment,starches extracted from three different Za-chilli were used as experimental materials to study on the relationship between its physicochemical properties,nutritional properties and food quality.The results showed that the starch granules became small and the surface became rough after fermentation,and only the corn starches of the three kinds of starch had obvious polarized cross,but as the fermentation proceeded,the polarized cross region became pale or even disappeared.The study of the degree of expansion showed that the fermentation significantly reduced the solubility of starch,and the swelling degree of the three starches varied.Fermentation increased the degree of expansion of corn starch,reduced the degree of swelling of and indica rice.the viscosity of starch characteristics studies showed that the waxy rice starch of Za-chilli was highest,followed by corn,and indica rice was lower,which was related to the composition of the Za-chilli starch.The study of the retrogradation characteristics of the three corn starches of Za-chilli was more susceptible to retrogradate,followed by indica rice,and waxy rice.The study on the freeze-thaw stability of starch shows that the precipitation rate of corn,indica rice starches of Za-chilli is larger than waxy rice,and the freezing and thawing stability is poor,easy to retrogradate.The study on the transparency of starch shows that there is a tendency for the transparency of the Za-chilli starch to decrease with the progress of the fermentation.This may be due to the fact that the microorganisms and the acid production during the fermentation process changing the crystal structure of the starch granules.The correlation analysis showed that the physicochemical properties of Za-chilli starch could only affect one aspect of the sensory evaluation of Za-chilli,while the comprehensive evaluation on the color,texture,aroma,taste and mouthfeel of Za-chilli was influenced by various physical and chemical characteristics.The study on the nutritional characteristics of three kinds of Za-chilli starch showed that the contents of amylopectin and amylose in the process of fermentation were reduced,and the amylopectin had a greater tendency to decline,which was easier to hydrolyze with amylopectin structure.The study of the digestive characteristics of three kinds of Za-chilli starch,and it was found that the content of RDS and SDS is relatively high,and the content of slow-digesting starch in corn and indica rice is much higher.Studies on the glycemic index and the hydrolysis index of Za-chilli starch from three starch sources show that fermentation can increase the glycemic index of starch.3.Preliminary research on the mechanism of carbohydrate changes in fermentationFor Za-chilli,the growth and decay of microorganisms,population and types,and extracellular enzyme properties have a crucial influence on the control of the entire fermentation system.Carbohydrates,as the main carbon source for microbial growth,are closely related to microorganisms.For this reason,the growth and decay of microbial population during the fermentation process of Za-chilli were studied.The results showed that the three microorganisms can produce different activities of amylase,cellulase,protease and lipase.Changes in starch and dietary fiber are mainly affected by the extracellular enzymes of microorganisms.Under the combined action of extracellular amylase,extracellular cellulase,and water and acid in the environment,they are decomposed into small molecules for microbial growth and lactic acid,Ethanol,acetic acid,etc.production.These end products,intermediates,and small molecules in the system are all involved in the biochemical reactions of the Za-chilli,forming a unique flavor.