Cm 3500d

The spread factor (diameter/thickness) of the non-gluten shortbread cookies was measured and calculated according to the American Association of Cereal Chemistry (AACC) (10–50.05) [26 ]. The loss rate was determined by comparing the weight of the cookies before and after baking. The hardness of the cookies was measured by using a texture analyser (TA.XT2i Texture Analyzer, Stable Micro System, Goldaming, Surrey, UK) with a P5 cylindrical probe under the following operating conditions: compression (return to start), test speed of 1.5 mm/s, strain deformation of 80%, 20 mm limit, and trigger force and speed of 10 gf and 10 mm/min, respectively [4 (link)]. The colour values (CIE L*; lightness, CIE a*; redness, and CIE b*; yellowness) of the cookies were measured by using a reflectance spectrophotometer (CM-3500d, Konica Minolta Sensing, Inc., Osaka, Japan). The water activity of the cookies was measured by using a water activity meter (Aqualab, Pullman, WA, USA).

Cookie chroma was measured according to the method of Siti Rashima (30 (link)). The color of biscuits was measured by a Konika Minolta reflectance spectrophotometer CM-3500d (Konica Minolta Sensing INC, Osaka, Japan) and the results were expressed using the CIE Lab color system. The three independent measurements of parameters a^* (redness), b^* (yellowing), and L^* (lightness) were conducted at different locations of the biscuit surface. The value E was calculated according to the equation:

The color differences were evaluated using a spectrophotometer (CM-3500d; Minolta, Kyoto, Japan). A white plate was used for standard calibration before measuring each specimen. The specimens were assessed according to the obtained a*, b*, and L* values, and ΔE* values were calculated according to the CIE Lab system. The color measurements were averaged at various locations on each specimen.

Color analysis of the samples was performed using a portable colorimeter (Minolta CM-3500d, Tokyo, Japan). The instrument registered the light transmittance of the juices and expressed the results in the CIELAB color system. Internal calibration was performed with an opaque material provided by the manufacturer, and with distilled water. Pomegranate juice samples were poured in quartz cells with 1 mm of optical path. Measurements were carried out at room temperature. Samples were analyzed in triplicate.
Total soluble solids were measured using a digital refractometer DBR 95 (Giorgio Bormac s.r.l, Carpi, Modena, Italy) and expressed as Brix. Measurements were performed in triplicate. The pH of the samples was measured with a digital pH meter (Inolab pH level 1, WTW GmbH, Weilheim, Germany). A single measurement of pH was performed for each sample. These measurements were performed for the five juices (NT, HT, HPP, CO₂, CO₂-US) at two points of storage (0 and 28 days).

The oil color was measured according to the CIELab system under 2 degrees and DL65 illumination conditions, using a spectrophotometer (Konica-Minolta CM-3500d, Osaka, Japan). Palette colors were described using three parameters: lightness (L*, from black to white), and the chromatic components a* (from green to red), and b* (from blue to yellow). The other parameter used was chroma [C* = (2a*+2b*)/2].
Chlorophyll and carotenoid pigments were measured by using a spectrophotometer (Shimadzu UV-160A; Kyoto, Japan). The maximum absorption at 670 and 470 nm is related to the chlorophyll and carotenoid fractions, respectively. They were used for calculation of the total content of these pigments in olive oil according to the method described by Minguez-Mosquera et al. [26 (link)]. The values of the coefficients of specific extinction applied were E0 = 613 for pheophytin as a major component in the chlorophyll fraction and E0 = 2000 for lutein as a major component in the carotenoid fraction. The pigment contents were calculated as follows: $\mathrm{Chlorophyll}\left(\mathrm{mg}/\mathrm{kg}\right)=\frac{A_{670}\times DF}{613\times Ws}$
$\mathrm{Carotenoid}\left(\mathrm{mg}/\mathrm{kg}\right)=\frac{A_{470}\times DF}{2000\times Ws}$
where A is the absorbance, DF is dilution factor, and Ws is the sample weight.

The colour stability after irradiation and water sorption of the 3D printing resin was determined according to ISO 4049:2019 standards [31 ]. The specimen was disc shaped, 15 mm in diameter and 1.0 mm in height.
The specimens used in the colour stability test were prepared as in Figure 1. The CIELAB coordinates of each specimen were measured using a spectrophotometer (CM-3500d; Konica Minolta, Sensing Inc., Osaka, Japan). In the CIELAB system, the location of a particular shade in the colour space is defined by three coordinates: L*, a*, and b*. L* respresents the lightness of the object being evaluated. The a* value represents the colour on the red–green axis and b* represents the colour valueon the yellow–blue axis. Three sites were measured at random for each specimen, and the mean values and standard deviations were obtained. The classified specimens were subjected to colour comparison (ΔE) based on ISO 4049:2019 standards [31 ]. ΔE was calculated using the following equation: $$\Delta E={\left[{\left(\Delta L^{*}\right)}^2+{\left(\Delta a^{*}\right)}^2+{\left(\Delta b^{*}\right)}^2\right]}^{1/2}$$