Plasma-activated water effectively decontaminates steamed rice cake

Hardening of cheese is one of major issues that degrade the quality of Home Meal Replacement (HMR) foods containing cheese such as Cheese-ddukbokki rice cake (CD, stir-fried rice cakes with shredded cheese). The quality of cheese, such as pH, proteolytic, and flavor properties, depends on various lactic acid bacteria (LAB) used in cheese fermentation. The hardening of cheese is also caused by LAB. In this study, various LAB strains were isolated from CD samples that showed rapid hardening. The correlation of LAB with the hardening of cheese was investigated. Seven of the CD samples with different manufacturing dates were collected and tested for hardening properties of cheese. Among them, strong-hardening of cheese was confirmed for two samples and weak-hardening was confirmed for one sample. All LAB in two strong-hardening samples and 40% of LAB in one weak-hardening sample were identified as Latilactobacillus curvatus. On the other hand, most LAB in normal cheese samples were identified as Leuconostoc mesenteroides and Lactobacillus casei. We prepared cheese samples in which L. curvatus (LC-CD) and L. mesenteroides (LM-CD) were most dominant, respectively. Each CD made of the prepared cheese was subjected to quality test for 50 days at 10 °C. Hardening of cheese with LC-CD dominant appeared at 30 days. However, hardening of cheese with LM-CD dominant did not appear until 50 days. The pH of the LC-CD was 5.18 ± 0.04 at 30 days, lower than that of LM-CD. The proteolytic activity of LC-CD sample was 2993.67 ± 246.17 units/g, higher than that of LM-CD sample (1421.67 ± 174.5 units/g). These results indicate that high acid production and high protease activity of L. curvatus might have caused hardening of cheese.

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Non-thermal pulsed plasma activated water: environmentally friendly way for efficient surface modification of semiconductor nanoparticles

Green Chemistry ◽

10.1039/d0gc02619k ◽

2021 ◽

Author(s):

Pavel Galář ◽

Josef Khun ◽

Anna Fučíková ◽

Kateřina Dohnalová ◽

Tomáš Popelář ◽

...

Keyword(s):

Surface Modification ◽

Free Surface ◽

Thermal Plasma ◽

Environmentally Friendly ◽

Semiconductor Nanoparticles ◽

Reactive Species ◽

Pulsed Plasma ◽

Non Thermal Plasma ◽

Plasma Activated Water

Non-thermal plasma activated water can be used for cheap, easy and chemicals-free surface modification of nanoparticles, with all the reactive species originating solely in air and water.

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Analysis of plasma activated water by gliding arc at atmospheric pressure: Effect of the chemical composition of water on the activation

Journal of Applied Physics ◽

10.1063/5.0040035 ◽

2021 ◽

Vol 129 (23) ◽

pp. 233301

Author(s):

M. Wartel ◽

F. Faubert ◽

I. D. Dirlau ◽

S. Rudz ◽

N. Pellerin ◽

...

Keyword(s):

Chemical Composition ◽

Atmospheric Pressure ◽

Pressure Effect ◽

Gliding Arc ◽

Chemical Composition Of Water ◽

Plasma Activated Water

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Plasma-Activated Water (PAW) as a Disinfection Technology for Bacterial Inactivation with a Focus on Fruit and Vegetables

Foods ◽

10.3390/foods10010166 ◽

2021 ◽

Vol 10 (1) ◽

pp. 166

Author(s):

Aswathi Soni ◽

Jonghyun Choi ◽

Gale Brightwell

Keyword(s):

Fruit And Vegetables ◽

Atmospheric Plasma ◽

Model Systems ◽

Thermal Treatments ◽

Bacterial Cells ◽

Bacterial Inactivation ◽

Gas Temperature ◽

Bacterial Strains ◽

Sensory Qualities ◽

Plasma Activated Water

Plasma-activated water (PAW) is generated by treating water with cold atmospheric plasma (CAP) using controllable parameters, such as plasma-forming voltage, carrier gas, temperature, pulses, or frequency as required. PAW is reported to have lower pH, higher conductivity, and higher oxygen reduction potential when compared with untreated water due to the presence of reactive species. PAW has received significant attention from researchers over the last decade due to its non-thermal and non-toxic mode of action especially for bacterial inactivation. The objective of the current review is to develop a summary of the effect of PAW on bacterial strains in foods as well as model systems such as buffers, with a specific focus on fruit and vegetables. The review elaborated the properties of PAW, the effect of various treatment parameters on its efficiency in bacterial inactivation along with its usage as a standalone technology as well as a hurdle approach with mild thermal treatments. A section highlighting different models that can be employed to generate PAW alongside a direct comparison of the PAW characteristics on the inactivation potential and the existing research gaps are also included. The mechanism of action of PAW on the bacterial cells and any reported effects on the sensory qualities and shelf life of food has been evaluated. Based on the literature, it can be concluded that PAW offers a significant potential as a non-chemical and non-thermal intervention for bacterial inactivation, especially on food. However, the applicability and usage of PAW depend on the effect of environmental and bacterial strain-based conditions and cost-effectiveness.

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