Texture exponent 32

The resistance to compressive deformation (hardness) was evaluated under ambient conditions using a TA HD Texture Analyser (Stable Microsystem Ltd., Surrey, UK) with a load cell of 5 kg. The results were processed using the Texture Exponent 32 software program (Stable Microsystem Ltd., Surrey, UK). The hardness was measured by compressing the formulations (n = 3) in the middle, at the tip, and vertically with the help of a 6 mm-diameter (P/6) probe using a trigger force of 0.001 N, a penetration depth of 2 mm, a test speed of 1 mm/s, and a return distance of 10 mm.

PLA (M_w = 280 kDa, M_w/M_n = 1.98) used in this experiment was obtained from Natureworks LLC (Blair, NE, USA). Acetyl tributyl citrate (ATBC) was purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China). Nano-Ag was purchased from Wanjing New Material Co., Ltd. (Hangzhou, China). Dichloromethane, methanol, NaOH, hydrogen peroxide, Na₂CO₃ were obtained from Chengdu Kelong Chemical Co., Ltd. (Chengdu, China). DPPH, Guaiacol were purchased from Sigma (St. Louis, MO, USA). All the reagent were analytical reagent. Texture analyzer (Texture Exponent 32, Stable Micro Systems Ltd., London, UK), Colorimeter (WSC-S; Shanghai Precision Instrument Co., Ltd., Shanghai, China), Digital Refractometer (MZB 92, Shanghai Miqingke Industrial Testing Co., Ltd., Shanghai, China), PH meter (Merck, Barcelona, Spain), spectrophotometry (UV-1800, Mapada Instruments Co., Ltd., Shanghai, China), Centrifuged (TGL-16M, Xiangyi Centrifuge instruments Co., Ltd., Shanghai, China).

The volume of breads was determined by rapeseed displacement according to the AACC Method 10-05.01 [32 ]. Specific volume was calculated as loaf volume and bread weight ratio.
Bread porosity was determined using Zhuravlev device (Biomer Ltd., Krasnoobsk, Russia) according to a previously described method by Cizeikiene et al. [33 (link)].
Analysis of bread texture was performed by means of a TA.HD.Plus texture analyzer (Stable Microsystems, Godalming, UK) according to AACC 74-09 with some modifications [34 ]. Trigger force was set at 0.049 N. Two slices of mechanically sliced bread (7 mm thick) were compressed with 25 mm aluminum cylindrical probe at 1.7 mm/s speed. The original software Texture Exponent 32 (Stable Microsystems, Godalming, UK) allowed the measurement of peak positive force (N), which describes hardness and peak negative force (N) describing bread stickiness. Analysis was performed 24 h after baking. The results are means of ten replicates.

The firmness of the tomatoes was measured by means of a standard puncture test, performed with a Texture Analyzer TA-TX2 (Stable Micro Systems Ltd., Surrey, UK; software: Texture Exponent 32, Stable Micro Systems Ltd.). The penetration depth was equal to 10 mm and a crosshead speed of 2 mm s⁻¹ was used. Tests were carried out using a cylindrical probe with a diameter equal to 5 mm and a flat end. Firmness was determined as the maximum force registered during the test. Firmness was measured at the same locations where the skin color and biospeckle activity were determined.

Bread crumb firmness, cohesion, adhesion, springiness, and chewiness were measured on a TA‐XT2 texture analyzer (Texture Technologies Corp.) according to AACC method 74–09 modified with a 10 N load cell and a probe speed of 1.7 mm/sec, set 10 mm from the bread surface using a with a TA‐4 acrylic cylinder (25‐mm diameter, 35‐mm tall) probe. Applications software (Texture Exponent 32, V6.1.13.0, Stable Micro Systems Ltd.) and system macros were applied without modification. Texture measurement (12 values) was performed using three center samples from four loaves per treatment. Two bread slices were combined to make a 25‐mm thick sample for compression to 60% deformation. After initial deformation, samples rested for 5 s, followed by a second compression cycle. Firmness was a measurement of the maximum force of the first compression. Cohesiveness was the positive area of work of the second compression divided by that of the first compression. Springiness was expressed as the ratio of the distance of the detected height during the second compression and the original compression distance. Adhesiveness was measured as the negative area of compression one. Chewiness is expressed as firmness multiplied by cohesiveness and springiness. Samples were tested 24, 72, and 120 hr after baking.

The firmness of T. aurantialba was determined by a penetration test, using a texture analyser (Texture Exponent 32, Stable Micro Systems Ltd., London, UK) equipped with a cylindrical probe of 2 mm diameter. The sample was penetrated 5 mm in depth. The speed of the probe was fixed at 2 mm∙s⁻¹. From the force versus time curves, firmness was defined as the maximum force (Newton, N) [15 (link)].