Corona Discharge Power of Plasma Treatment Influence on the Physicochemical and Microbial Quality of Enoki Mushroom (Flammulina velutipes)

Abstract

Plasma treatment was widely known as an effective technology applied for contact-surface decontamination. Enoki (Flammulina velutipes) was an edible-medicinal mushroom with different phytochemicals and bioactive components beneficial for human health. Enoki mushroom had high respiration rate therefore it was highly perishable after harvesting. Moreover, it was greatly susceptible to microbial contamination but it was not feasible to be decontaminated by normal water washing. It’s urgent to extend shelf-life and control microbial criteria on this mushroom in dry manner without aqueous treatment. Corona discharge plasma was among 4 kinds of diverse cold atmospheric pressure plasma sources widely applied in food industry. This study demonstrated the influence of corona discharge plasma power values (control, 120, 150, 180, 210 W) on the physicochemical and microbial characteristics of Enoki mushroom during 10 days of storage at ambient temperature. Results showed that Enoki mushroom should be treated at 150 W of corona discharge plasma power to retain weight loss, total soluble solid, vitamin C in acceptable values while reducing total Aerobic count, Coliform, Enterobacteriaceae as much as possible. At the 10th day of storage, the weight loss, total soluble solid, vitamin C, total Aerobic count, Coliform, Enterobacteriaceae were recorded at 3.35±0.07%, 6.98±0.03 oBrix, 14.81±0.04 mg/100 g, 4.71±0.05 log CFU/g, 3.17±0.02 log CFU/g, 2.13±0.01 CFU/g, respectively. Findings of this research proved that corona discharge plasma pretreatment would be appropriate to maintain physicochemical properties and retard microbial loads on Enoki mushroom during preservation.

Recent advances in quality preservation of postharvest golden needle mushroom (Flammulina velutiper)

“…The golden mushroom has a high respiration rate and is susceptible to spoilage after harvest. Additionally, it is susceptible to microbial contamination and cannot be decontaminated by normal water washing 25 . As such, the application of drying methods to extend the shelf life of F. velutiper and control the microbiological standards has become an urgent priority.…”

“…Plasma is one of four widely used cold atmospheric pressure plasma sources in the food industry 84 . Minh et al 25 . investigated the effect of corona discharge plasma power (control, 120, 150, 180, 210 W) on the physicochemical and microbiological characteristics of F. velutiper stored at room temperature for 10 days.…”

“…Despite the abundance of nutrients and high physiological activity after harvesting, the vigorous respiratory metabolism increased the degree of senescence and water content, and high susceptibility to environmental stress (opening and stalk elongation) and microbial infestation (including pathogenic bacteria and spoilage bacteria) lead to the decay of F. velutiper . As such, its shelf life is short (generally 3–5 days), severely hindering the development of the golden mushroom industry 14,22‐26 …”

New preservation and detection technologies for edible mushrooms: A review

“…It is used in edible mushroom preservation, where it can preserve the color, pH, and texture of mushrooms and reduce weight loss rates 63 . Minh et al 64 . used corona discharge plasma to treat F. velutipes and showed that it could maintain physicochemical indicators such as weight loss, soluble solids, and ascorbic acid in the product, while effectively slowing the total bacterial count.…”

“…62 It is used in edible mushroom preservation, where it can preserve the color, pH, and texture of mushrooms and reduce weight loss rates. 63 Minh et al 64 used corona discharge plasma to treat F. velutipes and showed that it could maintain physicochemical indicators such as weight loss, soluble solids, and ascorbic acid in the product, while effectively slowing the total bacterial count. Pourbagher et al 65 treated A. bisporus using surface media blocking discharge plasma technology, a method that effectively inhibited enzymatic browning and inactivated Pseudomonas torulosa, extending the storage life of the mushroom.…”