The Effect of Plasma Treated Water Unit Processes on the Food Quality Characteristics of Fresh-Cut Endive

Abstract

This study evaluated the impact of a defined plasma treated water (PTW) when applied to various stages within fresh-cut endive processing. The quality characteristic responses were investigated to establish the impact of the PTW unit processes and where PTW may be optimally applied in a model process line to retain or improve produce quality. Different stages of application of PTW within the washing process were investigated and compared to tap water and chlorine dioxide. Fresh-cut endive (Cichorium endivia L.) samples were analyzed for retention of food quality characteristics. Measurements included color, texture, and nitrate quantification. Effects on tissue surface and cell organelles were observed through scanning electron and atomic force microscopy. Overall, the endive quality characteristics were retained by incorporating PTW in the washing process. Furthermore, promising results for color and texture characteristics were observed, which were supported by the microscopic assays of the vegetal tissue. While ion chromatography detected high concentrations of nitrite and nitrate in PTW, these did not affect the nitrate concentration of the lettuce tissue post-processing and were below the concentrations within EU regulations. These results provide a pathway to scale up the industrial application of PTW to improve and retain quality characteristic retention of fresh leafy products, whilst also harnessing the plasma functionalized water as a process intervention for reducing microbial load at multiple points, whether on the food surface, within the process water or on food-processing surfaces.

Evaluation of lettuce (Lactuca sativa L.) in aquaponic system in terms of food safety

“…None of the measured force values were significantly different from the soil-grown lettuce samples. However, this may be due to the small sample size of n = 3 as in Schnabel et al (2021). Also, Lei and Engeseth (2021) stated that when compared to lettuce grown in soil, lettuce grown hydroponically has softer leaves and tighter midrib, which may be due to lignin in the cell wall.…”

Plasma-Treated Water Affects Listeria monocytogenes Vitality and Biofilm Structure

“…This basic research offers an extension of existing knowledge on the direct treatment of food products on an industrial scale. For this purpose, lettuce samples have already been treated with PTW according to industrial standards and examined for its qualitative change in color and microbial load (Schnabel et al, 2019b(Schnabel et al, , 2020(Schnabel et al, , 2021.…”

Influence of plasma-treated air on surface microbial communities on freshly harvested lettuce

“…Accordingly, a high level of food safety is obligate. Furthermore, this safety must be achieved without visually damaging the plant tissue that is purchased by consumers ( Cardinale et al, 2015 ; Schnabel et al, 2021 ).…”