Abstract
The influence of the texture of processed foods on parotid salivary secretion and mastication in humans were studied. Unilateral parotid saliva was collected from six subjects while they masticated and swallowed pieces of food obtained commercially. Processed foods were divided into 27 groups according to their texture, i. e., soft and hard, smooth and rough, and non-adhesive and adhesive. The water contents of the test foods were between 3% and 92%. The amounts of salivary flow showed specific fluctuations ranging from 0.01 to 1.33ml/g depending on the texture. Mastication time varied from 0.74 to 53.3sec/g. Significant correlations were observed between texture and mastication time. It was observed that the harder or rougher the texture, the greater the saliva flow and the longer the time needed for mastication up to swallowing. In nine foods having a high water content (between 70% and 92%), there was a correlation between the degree of softness and, salivary flow, and also between mastication time and the degree of softness. The rate of salivary flow for adhesive foods was higher than that for non-adhesive foods. These results indicated that the texture of processed foods obviously influences both the secretion of saliva and mastication time.
