Enhancement of nutraceutical components of mushroom by uv exposure and extension of their shelf-life using edible coating material adopting online assessment of keeping quality by Magnetic Resonance Imaging (MRI) technique

Abstract

To enhance the nutraceutical value and preservation of mushrooms, this study focused on augmenting two widely consumed mushroom varieties in India namely the Button Mushroom (Pleurotus ostreatus) and Oyster Mushroom (Agaricus bisporus). These mushrooms were subjected to UV light exposure to evaluate their impact on phytochemical content, including phenolics, flavonoids, folic acid, and Vitamin D2. The percent increase in phenolic content after 120 minutes of UV treatment was 0.6-fold for Agaricus bisporus and 0.7-fold for Pleurotus ostreatus. Notably, A. bisporus exhibited a particularly high phenolic content of up to 13.5 mg per gram dry weight of mushroom after 120 minutes of UV exposure, in contrast to P. ostreatus, which displayed 8.7 mg per gram dry weight of mushroom under the same conditions. This study also revealed a threefold increase in flavonoid content in Pleurotus ostreatus, rising from 1.2 mg of quercetin/g in the control to 4.1 mg of quercetin/g after UV exposure for 120 minutes. Conversely, a sevenfold increase in quercetin content was observed in Agaricus bisporus, surging from 0.45 g (control) to 3.2 g following 120 minutes of UV exposure. The exposure of UV light for 60 minutes resulted in the highest absorbance of vitamin D2 at 0.81 OD in Pleorotus osteatus compared to 0.46 in Agaricus bisporus. Additionally, applying agar or gelatine coatings led to a shelf-life extension of up to 14 days under standard storage conditions. The use of MRI for quality determination of mushrooms by evaluating the lipid profile in the samples was reported for the first time. This study has shown a significant enhancement of nutraceutical components of mushrooms with special reference to phenolics, flavonoids, folic acid, and vitamin D2 for value addition, with a simple intervention of UV treatment. Moreover, the shelf life of mushrooms could be enhanced by agar and gelatin coating thereby extending the keeping quality. The use of MRI for evaluating the quality of mushrooms has also been the hallmark of this study. The practical utility of all the above findings has immense industrial application in the large-scale production of highly nutritive mushrooms.