Salivary secretion and chewing: stimulatory effects from artificial and natural foods

Abstract

he aim of the present study was to determine the relationship between the flow rate of saliva and characteristics of the food. Therefore, we determined the rate of saliva secretion in 16 healthy subjects in rest and while chewing natural and artificial foods (toast with and without margarine, three sizes of breakfast cake, and Parafilm). We also determined the chewing rate, number of chewing cycles until swallowing, and time until swallowing. The physical characteristics of the foods were quantified from force-deformation experiments. The results showed that the average at which mechanical failure occurred (yield force) was 1.86 ± 0.24 N for the breakfast cake and 16.3 ± 1.3 N for the melba toast. The flow rates obtained without stimulation and with Parafilm were significantly lower (P < 0.001) than the flow rates obtained from chewing food. No differences in flow rate occurred between the natural foods. The flow rates of the saliva as obtained without stimulation, with Parafilm stimulation, and with chewing on the various foods were significantly correlated (P < 0.05). There were no significant differences in chewing rate among the foods. The number of chewing cycles and the time until swallowing significantly depended on the type or volume of the food. UNITERMS: Saliva; Flow Rate; Mastication; Food. objetivo deste estudo foi determinar a relação entre o fluxo salivar e características de diferentes alimentos. Avaliou-se a taxa de secreção salivar em 16 indivíduos saudáveis, sem estimulação, na estimulação com Parafilm e na mastigação de alimentos naturais (torrada com e sem margarina e 3 volumes de bolo industrial). Determinou-se também a velocidade, o tempo de mastigação, o número de ciclos mastigatórios até o limiar da deglutição. As características físicas dos alimentos foram quantificadas através da experimentação força-deformação. Os resultados mostraram que a média em que a falha mecânica ocorreu foi 1,86 ± 0,24 N para o bolo industrial e 16,3 ± 1,3 N para a torrada. Os fluxos salivares obtidos sem estimulação e com a estimulação pelo Parafilm foram significativamente menores (P < 0,001) que os fluxos salivares obtidos na mastigação dos alimentos naturais. Não houve diferença significativa no fluxo salivar entre os alimentos naturais. Os fluxos salivares obtidos sem estimulação, com estimulação pelo Parafilm e na mastigação dos vários alimentos foram significantemente correlacionados (P < 0,05). Não houve diferença significativa na velocidade da mastigação entre os alimentos. O número de ciclos mastigatórios e o tempo de mastigação até o limiar da deglutição dependeram do tipo e do volume do alimento.

Retro-Nasal Aroma Release Is Correlated with Variations in the In-Mouth Air Cavity Volume after Empty Deglutition

“…Before samples were collected, each subject was asked to swallow to empty the mouth of saliva, and nonstimulated whole saliva was collected by instructing the subject to spit out saliva into a preweighed cup every 30 seconds for 5 min [24]. rSF was measured once during the two sessions.…”

Masticatory function, taste, and salivary flow in young healthy adults

“…A sufficient amount of saliva is important for appropriate masticatory function (1). Salivary secretion is mainly induced during eating, and the perception of food texture is mediated by saliva (2).…”

Analysis of the association between lactotransferrin (LTF) gene polymorphism and dental caries

“…Cavities may appear whether cariogenic microorganisms and carbohydrates are present in a susceptible individual during a certain time in the mouth 7 . So far, researches have investigated several biological determinants, which can influence the biofilm cariogenicity 11,30 , like saliva flow and composition 8,27 . A constant salivary flow efficiently eliminates microorganisms from oral cavity.…”