Characterizing the Dynamic Textural Properties of Hydrocolloids in Pureed Foods-A Comparison Between TDS and TCATA

Abstract

Pureed foods, a compensatory diet for dysphagia, require the incorporation of hydrocolloids in order to be swallowed safely. The effect of hydrocolloid addition on textural dynamics of pureed foods has not yet been investigated. Starch and xanthan were added to levels that allowed products to meet the criteria of the International Dysphagia Diet Standardization Initiative. Nine pureed carrot matrices made with two concentrations of starch, xanthan, and their blends were characterized for textural evolution using two dynamic sensory techniques: Temporal Dominance of Sensations (TDS) and Temporal Check-All-That-Apply (TCATA). Each test, with four replications, was conducted with 16 panelists. Results indicate that purees were divided into two groups based on sensory responses--grainy and smooth were the primary differentiating attributes for these two groups. Grainy was associated with starch-added samples, while samples with xanthan (alone and in blends) were smooth and slippery. For both groups, thickness was perceived during the first half of processing, adhesiveness in the second half of oral processing, and mouthcoating was perceived toward the end of processing. A comparison of results from these tests showed that both TDS and TCATA gave similar information about texture dynamics and product differentiation of pureed foods.

Keywords: International Dysphagia Diet Standardization Initiative (IDDSI); carrots; dynamic perception; oral processing; pureed foods; starch; temporal check-all-that-apply (TCATA); temporal dominance of sensations (TDS); xanthan.

Figure 1

Standardized TDS curves of five pureed carrot matrices made with starch and xanthan: (A) control (no starch/xanthan), (B) 0.4% starch, (C) 0.8% starch, (D) 0.2% xanthan, and (E) 0.4% xanthan.

Figure 2

Standardized TDS curves of four pureed carrot matrices made with starch and xanthan blends (S—starch, X—xanthan, number represent the w/w percent concentration in pureed carrots): (A)—S0.4/X0.2, (B)—S0.4/X0.4, (C)—S0.8/X0.2, and (D)—S0.8/X0.4.

Figure 3

Standardized TCATA curves of five pureed carrot matrices made with starch and xanthan: (A)—control (no starch/xanthan), (B)—0.4% starch, (C)—0.8% starch, (D)—0.2% xanthan, and (E)—0.4% xanthan.

Figure 4

Standardized TCATA curves of four pureed carrot matrices made with starch and xanthan blends (S—starch, X—xanthan, number represent the w/w percent concentration in pureed carrots): (A)—S0.4/X0.2, (B)—S0.4/X0.4, (C)—S0.8/X0.2, and (D)—S0.8/X0.4.

Figure 5

Difference curves of pureed carrot matrices between control and two starch concentrations (0.4% and 0.8% w/w). TDS (left columns) and TCATA (right columns). Comparisons are made between a pair of samples, the first and second sample are depicted respectively above and below the zero line. Significantly different attributes varying between the samples are shown, calculated at 95% Fischer’s Exact test.

Figure 6

Difference curves of pureed carrot matrices between control and two xanthan concentrations (0.2% and 0.4% w/w). TDS (left columns) and TCATA (right columns). Comparisons are made between a pair of samples, the first and second sample are depicted respectively above and below the zero line. Significantly different attributes varying between the samples are shown, calculated at 95% Fischer’s Exact test.

Figure 7

Product map discriminating the nine pureed carrot matrices (w/w) made with starch, xanthan and their blends, using CVA analysis. (A) TDS, (B) TCATA. The sample names are in blue, attributes are in red and the connecting black line between the samples is an indicator of their similarities. The samples are control (no starch/xanthan), starch (0.4, 0.8), xanthan (0.2, 0.4), S0.4/X0.2, S0.4/X0.4, S0.8/X0.2, and S0.8/X0.4.

Figure 7

Product map discriminating the nine pureed carrot matrices (w/w) made with starch, xanthan and their blends, using CVA analysis. (A) TDS, (B) TCATA. The sample names are in blue, attributes are in red and the connecting black line between the samples is an indicator of their similarities. The samples are control (no starch/xanthan), starch (0.4, 0.8), xanthan (0.2, 0.4), S0.4/X0.2, S0.4/X0.4, S0.8/X0.2, and S0.8/X0.4.

Figure 8

A PCA biplot, depicting the sensory trajectory (TDS) at 11 equally spaced time points during oral processing of nine pureed carrot matrices made with starch (S), xanthan (X), and their blends (S/X). The nine samples are each indicated by a different number and each trajectory ends where the number appears in a colored square box. Some of the numbers are overlapping due to similarities. S—starch, X—xanthan. 1-Control (black), 2-S 0.4/X 0.2 (red), 3-S 0.4/X 0.4 (green), 4-S 0.8/X 0.2 (blue), 5- S 0.8/X 0.4 (turquoise), 6-S 0.4 (pink), 7-S 0.8 (yellow), 8-X 0.2 (grey), and 9-X 0.4 (navy blue).

Figure 9

A PCA biplot, depicting the sensory trajectory (TCATA) at 11 equally spaced time points during oral processing of nine pureed carrot matrices made with starch (S), xanthan (X) and their blends (S/X). The nine samples are each indicated by a different number and each trajectory ends where the number appears in a colored square box. Some of the numbers are overlapping due to similarities. S—starch, X—xanthan. 1-Control (black), 2-S0.4/X 0.2 (red), 3-S 0.4/X 0.4 (green), 4-S 0.8/X 0.2 (blue), 5-S 0.8/X 0.4 (turquoise), 6-S 0.4 (pink), 7-S 0.8 (yellow), 8-X 0.2 (grey), and 9-X 0.4 (navy blue).