Mastication process

A substance which added to rubber in very small amounts (0.1-0.2 phr) speeds up the normal mastication process and produces rubber of a given plasticity in a shorter time and with less power consumption. The accelerator MBT has a peptising action but certain thiophenols, mercaptans and particularly o-o-dibenzoylaminodiphenyl disulphide are much more effective. 

We can determine what features of the chewing sequence influence assessment of particular textural characteristics of food by using this approach to examine the interaction between food and consumer during the mastication process. We should then be able to develop mathematical models for perception of textural qualities which take into account different texture combinations (for example, assessment of hardness in both elastic and brittle foods), and different breakdown patterns. Although currently at an early stage, mastication analysis shows promise for enhancing our measurement of perceived texture in foods. 

There would be considerable advantage for both sensory scientists and the food industry in knowing what consumers are measuring in order to assess particular textural properties. Despite many real advances in the instrumental measurement of food texture, we are not significantly closer to understanding the sensory cues used in consumer assessment of texture. The mastication process is adjusted to the consistency of the food bolus in real time. From studies of this process is emerging a novel approach to characterisation of food texture. 

By means of co-mastication processes some reactions of PVC with nitrile rubber could be activated which proved to be of a practical importance [303], In this case, the temperature, duration and elastomer concentration are also the main parameters influencing the process. The dependence of the impact strength on concentration and duration is illustrated by the constant level curves in the plane of the two variables. Figure 3.238. 

Some of the new polymers formed will be block copolymers although combination of like radicals will also lead to homopolymers being present. There is of course no control on block length. Furthermore, as reaction proceeds the diblock polymers formed early in the mastication process may themselves become ruptured and their subsequent recombination may lead to more complex polyblock structures, the complexity of the structure increasing with the time of the reaction. It is reasonable to presume that, as the reaction proceeds, the concentration of pure homopolymer will decrease and that... 

Experimental results using the above assumed can be compared with the literature value for elongational flow. The measured ds are 50 times lower than the literature value, meaning that the actual saliva stress in the mastication process is 50 Pa. Under shear flow, there is a rapid increase in capillary number when tld/flc > ... 

The addition of a stable free radical (product of the oxidation of 2,2,4-trimethyl-6-ethoxy-l,2-dihydroquinoline) to rubbers prior to mastication permitted the use of ESR in studying the rubber mastication process at near ambient temperature. The radical concentration has been determined in this way after a various number of masticator passes [115, 116]. 

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