Texture profile analysis

The textural characterisation of the jellies was made by using the empirical technique of Texture-Profile Analysis (TPA) that allows the evaluation of the following parameters fracturability, hardness, cohesiveness, adhesiveness, springiness, gumminess and chewiness. 

Texture profile analysis is an empirical technique of double-penetration that simulates two bites of the jaw action. Data obtained from the Force-time plots enable the evaluation of seven texture parameters (Figure 1). 

The data from sensory evaluation and texture profile analysis of the jellies made with amidated pectin and sunflower pectin were subjected to Principal component analysis (PC) using the statistical software based on Jacobi method (Univac, 1973). The results of PC analysis are shown in figure 7. The plane of two principal components (F1,F2) explain 89,75 % of the variance contained in the original data. The attributes related with textural evaluation are highly correlated with the first principal component (Had.=0.95, Spr.=0.97, Che.=0.98, Gum.=0.95, Coe=0.98, HS=0.82 and SP=-0.93). As it could be expected, spreadability increases along the negative side of the axis unlike other textural parameters. 

Paraskevopoulou, A., and Kiosseoglou, V. (1997). Texture profile analysis of heat-formed gels and cakes prepared with low cholesterol egg yoUc concentrates. /. Food Sci. 62, 208-211. 

Pons, M., and Fiszman, S. M. (1996). Instrumental texture profile analysis with particular reference to gelled systems. /. Texture Stud. 27,597-624. 

For mashed potato texture, profile analysis (TPA) and cone penetration tests are performed with a TA HDi Texture Analyser (Stable Micro Systems Ltd, Godaiming, UK). During the tests, the mashed potatoes are kept at 55° C by means of a temperature-controlled Peltier cabinet (XT/PC) coupled to a separate heat exchanger and PID control unit. For the cone penetration tests, a spreadability rig is used, consisting of a 45° conical perspex probe (P/45°C) that penetrates a conical sample holder containing 7 0.1 g of mashed potatoes (Alvarez et al., 2005 Canet et al., 2005b Fernandez et al, 2006). 

A detailed method to perform texture profile analysis (TPA) on raw and cooked potatoes has been described by Kaur et al. (2007). The raw or cooked cylindrical pieces are prepared as described... 

Figure 9.2 A typical texture profile analysis force-time curve for raw potato. (Source Singh et al., 2008).

Table 9.2 Texture profile analysis parameters of raw potatoes of different cultivars... 

Gels for quantitating gel characteristics were prepared In screw capped centrifuge tubes (22 X 100 mm) by heating at 100 C for 15 min C14, l, l, ). Gel strength was determined by a penetration technique using the Instron fitted with a disk probe (6.0 ran diameter) (15.16). Instrumental texture profile analysis on gel sections (1.5 X 1,0 cm) was done on an Instron fitted with a... 

H2.1 General Compressive Measurements H2.2 Textural Measurements with Special Fixtures H2.3 Texture Profile Analysis... 

Figure H2.3.1 A generalized texture profile analysis curve from the Instron Universal Testing Machine. A1, area 1 A2, area 2 A3, area 3. The dotted lines indicate the times at which hardness is measured. See text for further discussion. Reprinted from Pons and Fiszman (1996) with permission from Food and Nutrition Press.

Table H2.3.1 Parameters and Units of Instrumental Texture Profile Analysis"...

Breene, W.M. 1975. Application of texture profile analysis to instrumental food texture evaluation. J. Texture Stud. 6 53-82. 

TMCS trimethylchlorosilane imidazole TMG tetramethylguanidine TMP 1,1,3,3-tetramethoxypropane TMS trimethylsilyl TNBS trinitrobenzenesulfonic acid TOCSY total correlation spectroscopy TPA texture profile analysis TPCK Af-tosyl-L-phenylalanine chloromethyl ketone... 

Martinez, O., Salmeron, J., Guillen, M.D., and Casas, C. 2004. Texture profile analysis of meat products treated with commercial liquid smoke flavourings. Food Control 15, 457-461. 

A double compression test, in which the same sample is subjected to two consecutive compressions and unloadings , forms the basis of the Texture Profile Analysis (TPA) technique, which yields mainly empirical... 

Most mechanical tests developed for fats are empirical in nature and are usually designed for quality control purposes, and they attempt to simulate consumer sensory perception (3, 4). These large-deformation tests measure hardness-related parameters, which are then compared with textural attributes evaluated by a sensory panel (3, 5). These tests include penetrometry using cone, pin, cylinder and several other geometries (3, 6-12), compression (13), extrusion (13, 14), spreadability (15, 16), texture profile analysis (2), shear tests (13), and sectility measurements (14). These methods are usually simple and rapid, and they require relatively inexpensive equipment (3, 4, 17). The majority of these tests are based on the breakdown of structure and usually yield single-parameter measurements such as hardness, yield stress, and spreadability, among others (4, 17-20). The relationship between these mechanical tests and the structure of a fat has, however, not been established. The ultimate aim of any materials science endeavor is to examine the relationship between structure and macroscopic properties. 

Texture determination textural properties of starch gels were determined using a TA-XT2 texture analyzer (Stable Micro Systems, Scarsdale, NY, USA). A textural profile analysis (TPA) test was performed using a 0.50 S sphere (0.5 in. diameter) probe on gels equilibrated to room temperature to measure hardness and adhesiveness. Only the samples with starch concentration of 10% (% s/w) could be analyzed because they had a texture that fell within the detectability limit of the instrument. At least ten replicates were rim for each gel. 

FIGURE 5.21 Hardness, cohesiveness, adhesiveness, and elasticity, as determined by texture profile analysis, of high-pressure sausages (350 MPa, 15 min, 7°C) stored at chilled temperatures (2 + 1°C). ( ) Control without chitosan ( ) with 1.5% chitosan powder. Different letters (a, b, c) indicate significant differences p < 0.05). (From Caballero, M.E.L. et al.,... 

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