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.

Snakeskin gourami (Trichogaster pectoralis) is one of the most common fish in paddy field and river in Vietnam. It lives in waters at low dissolved oxygen and high organic accumulation. It has a high meat yield and favouritely consumed as dried fish in Vietnam. Farming area of snakeskin gourami has been opened dramatically in recent years. Therefore, it’s necessary to have an appropriate processing and preserving approach to accelerate its commercial value in local and international markets. Objective of the present study focused on the different aspects such as ethanol treatment to eliminate fishy ordor; addition of salt, sorbitol, as well as dry temperature that affected to to water activity (aw), microbial load (coliform, cfu/g), sensory score of dried snakeskin gourami (Trichogaster pectoralis). Shelf-life of the dried product was also evaluated during preservation. Results showed that 40% ethanol at ratio 20:80 for primary treatment; 2.0% of salt soaking; 1.0% of sorbitol addition; 46°C of drying were appropriate to maintain water activity (aw=0.65). By preserving under vacuum in PA bag, the dry-salted snakeskin gourami still extended the product shelf-life for 12 months without any deterioration.

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Pineapple (Ananas comosus) was a non-climacteric fruit popularly distributed in Vietnam and other tropical regions. It was highly preferred by great appearance, wonderful texture, special flavour and perfect nutritional value. Moreover, it was also a good source of minerals, vitamins and antioxidants beneficial for human health. In harvesting season, it was highly perishable under ambient storage due to its high metabolic and moisture content resulting in quality degradation. This research evaluated the possibility of hot water treatment to the retention of quality attributes during storage. Pineapple fruits were dipped in hot water at different times and temperatures 30/35 (as control), 50/45, 52/40, 54/35, 56/30, 58/25, 60/20, 62/15 (°C/s). They were drained for 30 mins and stored at the ambient condition at the relative humidity of 85-90% for 15 days. In 3 day-interval, these fruit groups were taken to evaluate weight loss, firmness, decay index, total soluble solids (TSS), ascorbic acid. Results showed that there was a significant difference between the control and 7 treated groups. Pineapple fruits treated by hot water at 56/30 (°C/s) showed the lowest weight loss (0.15±0.05 to 1.34±0.01%), the lowest decay index (1.03±0.02 to 1.63±0.02), the most firmness (19.43±0.00 to 18.63±0.03 N), the highest TSS (24.35±0.02 to 23.01±0.01oBx), the highest ascorbic acid content (18.59±0.01 to 17.79±0.02 mg/100 g). Application of hot water submergence provided an alternative to chemical treatment to extend pineapple stability during storage and improve its marketability in distribution

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