Which variables should be controlled when measuring the granulometry of a chewed bolus? A systematic review

Abstract

The distribution of food particles in a chewed bolus characterizes the food destruction after food oral processing (FOP). Previous reviews report that it could be affected by a lot of parameters as the number of chewing strokes, the dental status, but the conditions for producing reproducible data allowing inter‐studies comparison have not been clearly described yet. This systematic review aims to identify the variables that can affect bolus granulometry determination, and to calculate their relative weights in the median particle size (D50) variations. The systematic review focuses on granulometry expressed as D50 of the most used foods (peanuts, carrots, and almonds) and materials (Optosil and Optocal). Based on 58 studies, 5 variables among 60 being extracted could explain the D50 variations. Conceptual differences between the conditions for FOP should be considered. After Chewing‐test, the bolus is collected after a predefined number of strokes and its granulometry characterizes the effects of the dental and muscular apparatus on food destruction, while after Mastication‐test the bolus is collected at the swallowing threshold, and its granulometry reflects the outcome of the abilities of the subject to adapt his/her mastication behavior to food texture. Experimental conditions related either to physical sieving or image analysis used to analyze the collected boluses impact the D50 values. Finally, when type of test, sieving conditions, type of food or material, number of chewing strokes, and the oral status of the subjects are controlled, mean D50 values are reproducible and could be used for inter‐studies comparisons. Practical applications This review provides tables that could be useful to control mean D50 variations in further research.

Differences in comminution progress during mastication in healthy dentate and denture-wearing elderly people

“…Regarding the evaluation method for the particle analysis on mastication, Â50 is one of the most frequently used methods in this field [28]. Here, Â50 is an excellent method to characterize the particle size distribution with one representative value [29]. On the other hand, it is possible to evaluate two indices, particle homogeneity and size, separately using this method.…”

“…Several studies reported higher retrieve rates using silicone dental impression material as artificial test food [31]. However, Bonnet et al stated that the use of non-edible test material would be debatable, especially in the studies that aim to investigate swallowing threshold [29]. They mentioned synthetic materials, such as dental impression materials, were not supposed to be swallowed but induce nonnutritive mastication that generally depends on voluntary command and is more detached from neuro controls compared with mastication of natural food.…”

Effect of process-induced common bean hardness on structural properties of in vivo generated boluses and consequences for in vitro starch digestion kinetics

“…This finding was in agreement with previous studies stating that PSD of different chewed foods depends on food type but not on individuals, despite variations in masticatory parameters between subjects (11)(12)(13)15) . It has been previously reported that subjects adapt their mastication behaviour depending on factors such as physical food characteristics, including food texture (13,45) . Moreover, it has been postulated that a precisely determined bolus texture, which seems to depend on both particle size reduction and the creation of a cohesive bolus through lubrication with saliva, has to be achieved before swallowing occurs (11,13,15) .…”

Food matrix structure (from Biscuit to Custard) has an impact on folate bioavailability in healthy volunteers

“…The validation of these hypotheses could be done by in vivo (in appropriate animal models) or in vitro studies via a fine analysis of kinetics of food disintegration along the gut. From mechanical disintegration of food bolus in the mouth [34], to chemical and enzymatic disintegration of the bolus within the stomach and the duodenum/ileum [30,35] including interaction between folates and lipids (and maybe proteins) present in custard/milk in particular, many strands remain under research about the major food parameters that determine food behaviour during digestion and the related nutritional consequences.…”