Food oral processing is a new field of food science in recent years.It is the initial stage of human digestion of food.This process is not only the chewing and digestion of food,but also the evaluation of food texture and flavor.Chewing is an important part of oral processing.Changes in chewing parameters(chewing frequency,chewing time)will affect consumers’ perception of food texture and taste intensity.The research on chewing behavior can help consumers better adjust their eating behavior,promote a healthier lifestyle,and provide more reference for product design.The seeds of Euryale sibiricum are rich in nutrients.They can be used as a new type of oil crop or food raw material in some food formulations to increase the content of ω-3 fatty acids and dietary fiber.It has great research potential and development and utilization value in food,health care products and other industries.In this paper,biscuits with Chia seed addition of 0%,5%,10%,15%,and 20 % were used as research objects to explore the changes in the basic properties of Chia seed biscuits and the effects of chewing parameters on the taste quality of Chia seed biscuits.Finally,based on support vector machine(SVM),a support vector machine classification model was establish ed for biscuit bolus at different chewing times to analyze the chewing degree of the bolus.The research contents and results are as follows:1.The quality of Chia seed biscuits was evaluated.Five kinds of biscuits with 0%,5%,10%,15% and 20% Chia seed s(accounting for wheat flour)were made to explore the effect of Chia seeds on the quality of biscuits,including basic components,physical and chemical properties,chew parameters of evaluators and sensory evaluation.The results showed that the addition of chia seeds improved the nutritional value of biscuits.The fat,protein and dietary fiber of chia seeds were higher than those of wheat flour and rich in polyphenols.With the increase of chia seeds,the fat,protein,ash content and antioxidant prope rties of biscuits increased significantly,and the starch content decreased significantly.The addition of Chia seeds will enhance the hardness and fracture of biscuits,reduce the ductility of biscuits,and the Maillard reaction and caramelization reactio n in the heating process will deepen the color of biscuits,which will adversely affect the appearance of biscuits.The chewing parameters of biscuits by ten sensory evaluators showed that the chewing frequency of the evaluators increased with the increase of the amount of Chia seeds added.2.The effects of chewing frequency and chewing time on the taste quality of Chia seed biscuits were investigated.Five biscuits were processed by oral processing.The texture characteristics,moisture content and image texture analysis of the pellets after o ral processing were measured at different chewing frequencies(70 times/min and 90 times/min)and chewing times(15 s,30 s,45 s).Finally,in vitro experiments were conducted to evaluate the funct ional properties of biscuits.The results showed that with the increase of chewing frequency and time,the biscuit particles were ground more thoroughly,the saliva secretion increased,the moisture content of the food pellets increased,the texture of the food pellets became softer,and the surface of the food p ellets was smoother.The results of in vitro starch digestion showed that dietary fiber inhibited the digestion of starch,and the content of resistant starch was the highest under any chewing parameters.The changes of chewing parameters had no significant effect on the in vitro antioxidant results,and the addition of Chia seeds made the biscuits have higher antioxidant activity than ordinary biscuits during oral and gastrointestinal digestion.3.Based on principal component analysis,a SVM classificatio n model for the chewing degree of food balls was constructed.Based on the six texture features and four image texture features of the bolus under different chewing time,the principal component analysis method was used to reduce the dimension.Three,four and five principal components were selected to replace the original variables,and the chewing time of the bolus(15 s,30 s,45 s)was used as different categories to construct the SVM classification model.The final accuracy of the model was determined by5-fold cross validation.The results show that no matter how many principal components are selected,the total accuracy of the model classification is above 90%,and the classification effect is good.The accuracy rate is the highest when five principal components are selected,which is 98.05%. |