Inverstigation Of The Correlation Between Salivary Secretion And Food Preference

The oral processing of food begins with the first bite,and finish until the end of swallowing,food must be processed through the oral cavity before digested and absorbed by the human body.Salivary secretion and compositions change with the age,eating habits and oral environment of the person,reflecting the health of the human and the perception of taste.This subject is to discover the differences between salivary biochemical components and secretion from different ages,analyze the relationship between the salivary compositions and human aging and dietary preferences.Results can be uesd for food development,especially for special obstacles.The specific research contents and results are as follows:1)The salivary compositions of stimulated saliva(SS)secretion by chewing parafilm,chewing beeswax and using citric acid solution and unstimulated saliva(US)collected under resting were measured in this part.After centrifugation for 30 min under three different centrifugal forces of 500×g,1500 ×g and 15000 ×g,results analyzed by using two-way analysis of variance,to choose a method not only with the least influence on the measurement of salivary biochemical indicators,but also remain original physiological characteristics of saliva after collecting.Finally,500 ×g centrifugal force with almost no interaction with parafilm was selected for saliva collection.The collected saliva can both satisfy the determination of salivary biochemical indicators and preserve the physiological properties of saliva.2)Saliva biochemical components of 109 volunteers aged 21-89 among 1 university,2 nursing homes and 5 communities in Hangzhou were measured in this part,including salivary flow rate,total salivary protein content,salivary a-amylase activity(sAA),and lipolysis,carbonic anhydrase VI(CA-VI)and cystatin SN content,pH,sodium,magnesium,potassium,calcium ion content were determined.Correlation analysis,principal component analysis and clustering were used to explore the differences about biochemical composition of saliva with age.Two distinct correlation were found,total protein vs.?-amylase(US=0.470,p<0.01;SS=0.465,p<0.01);salivary lipase vs.cystatin SN(US=0.493,p<0.01;SS=0.461).Age has a certain influence on salivary secretion ability,but there are large differences among individuals.After cluster analysis,the great differences about salivary compositions were shown,which can be used as the basis for evaluating human saliva secretion ability.3)Food preferences results among 103 participants in the salivary secretion test were collected in this part,cluster analysis was used to study the correlation between food preferences and salivary biochemical components,and the differences of saliva between clusters group measured with data analysis.The difference between biochemical components and its relationship with sweetness,bitterness,and fatty taste sensitivity among 20 volunteers were measure.The standard chemicals are sucrose,6-n-propylthiouracil(PROP)and oleric acid respectively.Result founds that people with different food preferences had different sensitivity to fatty taste(p<0.05),and there was a significant difference in sweetness sensitivity between different saliva secretion groups(p<0.05).The experiment also found that the perception of fatty taste was moderately positively correlated with fatty diet preference person(recognition threshold(RT),r=0.577;stimulus threshold(ST)r=0.603),and there was a certain negative correlation with BMI value(recognition threshold r=-0.609,stimulus threshold r=-0.501).