Study On The Manufacturing Technique Of Instant Selenium-Enriched Pleurotus Eryngii Pickle

Selenium(Se)is one of the essential trace elements for its health benefits to human.The probiotic Lactic acid bacteria(LAB)can transform toxic inorganic Se into safe and bioavailable organic Se,so it can be used as a safe and efficient carrier for Se supplementation.Although fresh Pleurotus eryngii(P.eryngii)is a kind of edible fungus with high nutritional value,it is perishable,which restricts its circulation.Lactic acid fermentation is a simple and practical technology,which can maintain and improve the safety,nutrition,sensory characteristics and the shelf life of fruits and vegetables.Therefore,to produce Se-enriched P.eryngii pickle by virtue of LAB has broad application prospects.In this study,fresh P.eryngii was used as the main raw material.The optimum Se addition method,the optimum amount of Se addition,the optimum seasoning technology,sterilization method and storage temperature for the manufacture of Se-enriched P.eryngii pickles were explored.Finally,an instant Se-enriched P.eryngii pickle with a bright red color,spicy flavor,and crisp taste was developed,which might provide an alternative Se supplement way for Se-deficient population and enrich the deep processing form of P.eryngii.The main results are as follows:(1)Compared with adding sodium selenite directly into the fermentation substrate,the way to inoculate Se-enriched LAB was more beneficial to the growth and metabolism of LAB in the fermentation substrate.And the latter had a stronger improve effect on the total phenol content and DPPH radical scavenging activity.Se content in the fermented P.eryngii body was so high that there was a toxicity risk when eating.Therefore,it is necessary to explore the appropriate initial supplemental level of Se.In addition,Se-enriched LAB inoculation provided a desirable sour and umami taste.The treatment group of inoculating Se-enriched LAB had the most abundant volatile compounds,especially ester compounds.Moreover,the higher amounts of characteristic flavor substances were detected in the Se-enriched LAB treated group.(2)Determination of Se content showed that the optimum Se content was 7.89 ± 0.25?g/g FW under the medium Se supplemental level.Medium Se supplementation level had the strongest elevate effect on the total phenol content and DPPH free radical scavenging activity.Compared with the low Se and high Se level treated groups,medium Se level treated group had the strongest reduced effect on decreasing oxalic acid level.And the elevate effect of citric acid,malic acid and EUC levels was the strongest in the medium Se level treated group.The main aroma substances of low Se and high Se level treated groups were alcohols,acids and esters,which presented wine,cream and fruit fragrance.While the main aroma substances of medium Se level treated group were aldehydes and furans,and the overall flavor characteristics were fruit,grass and fatty fragrance.(3)The instant capsicol Se-enriched P.eryngii pickles had the best sensory quality.The pasteurized and high-temperature treated samples had an inferior sensory quality to unsterilized samples.In addition,compared with storing at 25?,samples stored at 4? had obtained a better sensory quality.The above results indicated that the inoculation of Se-enriched LAB was the most suitable way for manufacturing Se-enriched fermented P.eryngii.The medium Se supplementation level(0.4%(v/v))could endowed the final product with safer and better quality characteristics.Compared with pasteurization and high-temperature sterilization,there was no significant decline for the sensory quality of the unsterilized instant capsicol Se-enriched P.eryngii pickles after stored at 4? for 30 days.All indicators of the instant capsicol Se-enriched P.eryngii pickles prepared by the above technology met with relevant standards,which could be recognized as a novel,safe,nutritious and delicious Se-enriched food.