Effect Of Pressure Cooking On The Edible Quality Of Beef And Prediction

Beef has the characteristics of high protein,low fat and good flavor,which is widely favored by consumers.Edible quality and nutritional quality are important factors affecting beef consumption intention.Edible quality of beef can be affected by a variety of internal and external factors.Processing is the key factor in the formation of beefs characteristic flavor.However,there were few reports on the change of beef quality when cooking under the pressurized environment.This subject took beef as the research object.Firstly,we researched on the factors affecting beef consumption behavior of residents in Shanghai,which is representative of first tier cities in China,by investigating their scientific cognition,consuming behavior and cooking habits of beef.We clarified that stewing beef by pressure cooker is the more commonly used processing method.Then,the influence of pressure on beef quality was explored by analyzing the color,texture,and flavor indexes of beef cooked under different pressurized environments.Lastly,intelligent sensory technology combined with artificial sensory evaluation was used to establish the pressure-cooked beef quality prediction model.This research could provide some scientific basis for the development of beef products,culinary science and the development of kitchen appliances.The study was divided into the following three parts:1.Investigation on scientific cognition,consumption and cooking of beef in ShanghaiWe investigated and analyzed the scientific knowledge,consumption and cooking habits of beef among Shanghai residents by online study.In the survey population,women accounted for 60.95%;these volunteers mainly focused between 18-25 years old,accounting for 53%;the residence time in Shanghai is relatively balanced;the educational background is mostly concentrated in the two levels of College or University(46.04%)and master degree or above(50.12%);the occupational status is mostly salaried(48.68%)and students(45.8%).The results showed that the nutritional quality of high protein,low fat and rich minerals was the important characteristic for beef,but the edible quality had a greater impact on consumers' purchase intention;the increase of average monthly food consumption would significantly increase the consumption frequency of western style beef dishes(p<0.05);the residents born in Shanghai had a higher consumption frequency of western style beef dishes(p<0.05),The proportion of never consuming western style beef dishes decreases with the increase of residence time in Shanghai;the proportion of fresh beef purchased by people during 41-50 years old in the agricultural market was significantly higher than other people(p<0.05);the proportion of imported beef purchased by people with higher monthly income(20001RMB and above)or with overseas study background was higher;people with higher monthly food consumption per capita were more likely to buy fresh beef at the brand beef counter or supermarket and people with fitness habits were more likely to buy beef in the brand beef counter.Stewing was the most widely used cooking method of beef.Because of its time-saving and good flavor,pressure cooker became the first choice cooking utensils for beef stew.2.Effect of pressure cooking on the beef edible qualityThe color,texture,volatile flavor compounds and taste compounds of raw beef and beef cooked under different pressure were analyzed.The results showed that appropriate pressure can make the beef have a brighter color.With the increase of cooking pressure,b*value increased significantly(p<0.05);meanwhile,the hardness,elasticity,chewiness,adhesion,cohesion,resilience and shear force of beef decreased with the increase of cooking pressure,which showed that the beef cooked under higher pressure became easier to chew.A total of 364 volatile compounds were detected in beef,including acids,alcohols,aldehydes,esters,hydrocarbons,phenols,furans and their derivatives,nitrogen-containing sulfur compounds and other substances.The content of aldehydes was the highest,which means aldehydes were the main volatile flavor substance in beef samples.Various volatile components produced by the Maillard reaction of beef,such as dimethyl trisulfide,furan,pyrazine,pyridine,thiophene,had a great contribution to the aroma of cooked meat.17 kinds of free amino acids were detected in beef,and glutamic acid had a great contribution to the overall taste.Other taste compounds had the auxiliary effect on the overall taste of beef under the content of sub threshold.A large amount of flavor substances in cooked beef were dissolved in the soup,so the content of total amino acids and total nucleotides in raw beef was significantly higher than that of cooked beef(p<0.05),and the corresponding TAV and EUC values are also significantly higher than that of cooked beef(p<0.05).3.Prediction of edible quality of cooked beef under pressure based on intelligent sensory technologyIn sensory evaluation,the score of meaty,fatty,sweet and chewiness were positively correlated with overall liking,while bloody and milky flavor were negatively correlated;sulfur compounds and small molecular aldehydes had important contribution to meaty flavor and fatty flavor.Based on three intelligent sensory technologies including machine vision,electronic nose and electronic tongue,the appearance,aroma and taste of beef cooked under different pressures were analyzed.LDA model constructed by fusion data of texture information of beef,which extracted by wavelet transform,electronic nose and electronic tongue sensor data,could distinguish different beef samples;sensory characteristic prediction model was established by fusion data of three intelligent sensory combined with BPNN algorithm can effectively predict 8 sensory evaluation indicators,including brownness,clarity of texture,chewiness,fiber,hardness,juiciness,meaty odor and off-flavor.