Effects of cold plasma on the color parameters of Hyssop (Hyssopus officinalis L.) using color imaging instrumentation and spectrophotometer

Abstract

This research was conducted to evaluate the effects of cold atmospheric plasma treatment on the color of Hyssop (Hyssopus officinalis L.) and also to compare the usage of the spectrophotometer vs the color imaging instrumentation for the evaluation of the treatment on the color parameters. The experiments were investigated at different treatment times of 1, 5, and 10 minutes and the voltage values of 17, 20, and 23 kV. Possible changes of color were evaluated by using CIE L*a*b* values obtained with HunterLab colorimeter and CIE L*a*b* values obtained with a digital still camera (DSC) using digital image processing (MATLAB software). The values of L*, a*, and b* of the samples were obtained using both the methods. The results revealed that the L*, a*, and b* values of the treated Hyssop samples changed with increasing the treatment time and the voltage applied. Evaluating the interaction effects revealed that there was a significant difference in the (−a*/b*) ratio. In addition, the results showed that the effects of all variables on the color parameters were significantly different in the case of the DSC using digital image processing. However, these effects were not significantly different using HunterLab colorimeter except for time variable and interaction effects of a* and (−a*/b*) ratio. The lightest green color and the maximum chlorophyll content loss were observed for 23 kV applied over 10 minutes. Based on the results, the digital image processing can be used as a practical tool to study the variations at the color of dried Hyssop leaves after cold plasma treatment.

Exploring Multifaceted Changes in Physicochemical and Nutritional Attributes of Chicken Breast Powder under Cold Plasma Treatment

“…Additionally, the b* value increased from 24.87% (CP-5) to 56.30% (CP-15) relative to CP-0, while the a* value decreased from 20.32% (CP-5) to 18.13% (CP-10) relative to CP-0. These color observations align with the findings of Rezaei et al 38 and Hemmati et al 39 The TCD is used to identify the difference in color parameters, i.e., L*, a*, and b*. According to Adekunte et al, 40 TCD can be categorized as very distinct (TCD > 3), distinct (1.5 < TCD < 3), and small difference (TCD < 1.5), with treatments exhibiting lower TCD deemed more appealing to consumers.…”

Increasing the efficiency of cumin essential oil extraction using cold plasma pretreatments

“…In freshly cut kiwi, chlorophyll reduction was observed due to CP treatments 34 . In hyssop, using CP for 10 min at 23 kV, the treated sample had a higher Δ E value (6.33) among other values 35 . Plasma modifies the superficial characteristics of materials with a chemical reaction 36 .…”

“…34 In hyssop, using CP for 10 min at 23 kV, the treated sample had a higher ΔE value (6.33) among other values. 35 Plasma modifies the superficial characteristics of materials with a chemical reaction. 36 Based on the literature review, the mechanisms may be as follows: (i) physical change following the bombardment of electrons and ions and (ii) oxidation of outer surface compounds and cell damage.…”

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“…The effect of cold plasma on color values can vary depending on many parameters, including the experimental setup, power, and treatment time. It was reported that cold plasma treatment caused changes in the color parameters of dried hyssop leaves with increasing voltage and exposure time (Rezaei et al., 2020 ).…”