Shelf life extension of white mushrooms (Agaricus bisporus) by low temperatures conditioning, modified atmosphere, and nanocomposite packaging material

Development of ultra-thin poly(L-lactic acid)-based films integrating toughness, barrier properties, and gas selectivity: Towards gas-permeation controllable green food packaging

High costs and low performance have constrained the application of bio-based materials in food packaging. Herein, a series of ultra-thin poly(L-lactic acid-iconic acid N-diol) (P(LA-NI)) copolymer films were developed using a "one-step" polycondensation process with integrated toughness, barrier properties, gas selectivity, and quality control features. The massive branched structure and gg conformers in P(LA-NI) act as "internal chain expansion" and "internal plasticization". Meanwhile, P(LA-NI) contains numerous polar groups and unique nanoscale microphase structures to realize excellent CO2, O2 barrier, CO2/O2 selectivity, anti-fogging, and UV shielding functions. The atmosphere within the package spontaneously achieves the desirable low O2 and high CO2 levels when packaging button mushrooms with high respiratory metabolism. Eventually, the shelf life of button mushrooms reached 24 days, >3-fold extended. This PLLA-based film meets "dual carbon" and "food safety" goals and has vast potential for fresh food preservation.

Infusion of active compound into sliced button mushrooms through vacuum impregnation to improve functionality: Comparing response surface methodology and artificial neural network

The present study explores the infusion of active compounds (ascorbic acid and calcium lactate) into sliced button mushrooms (Agaricus bisporus) to increase the nutritional value and reduce the browning effect of sliced mushrooms using the vacuum impregnation (VI) technique. The aim was to functionalize the vacuum-infused sliced mushrooms and evaluate the physicochemical properties of button mushrooms for diversifying food use. The central composite design was implemented to determine the optimized condition for the process with four independent factors, that is, immersion time (IT) 30-90 min, solution temperature (ST) 35-55°C, solution concentration (SC) 4%-12%, and vacuum pressure (VP) 50-170 mbar. The optimum VI processes obtained were ST-40°C, SC-8%, VP-140 mbar, and IT-65 min with a desirability function of 0.77. Statistically, two models (response surface methodology [RSM] and artificial neural network [ANN]) were employed to compare the better performance for the prediction of VI operational process parameters. The RSM model showed a better prediction of VI process parameters than the ANN model, with a higher R2 value (0.9228 vs. 0.8160) and lower root mean square error value (1.4004 vs. 2.1751), χ2 (2.4491 vs. 5.2762), mean absolute error (1.1177 vs. 1.1611), and absolute average deviation (4.3532 vs. 5.6746) for water loss. A similar pattern was observed for solute gain, ascorbic acid, titratable acidity, color change, firmness, and pH. Therefore, the VI process was found to be an effective method for enhancing the nutritional properties of sliced mushrooms. These findings concluded that the RSM model is more efficient for better prediction with good accuracy of the VI process than the ANN model.

Pre- and Postharvest Strategies for Pleurotus ostreatus Mushroom in a Circular Economy Approach

Mushroom cultivation presents a viable solution for utilizing agro-industrial byproducts as substrates for growth. This process enables the transformation of low-economic-value waste into nutritional foods. Enhancing the yield and quality of preharvest edible mushrooms, along with effectively preserving postharvest mushrooms, stands as a significant challenge in advancing the industry. Implementing pre- and postharvest strategies for Pleurotus ostreatus (Jacq.) P. Kumm (oyster mushroom) within a circular economy framework involves optimizing resource use, minimizing waste, and creating a sustainable and environmentally friendly production system. This review aimed to analyze the development and innovation of the different themes and trends by bibliometric analysis with a critical literature review. Furthermore, this review outlines the cultivation techniques for Pleurotus ostreatus, encompassing preharvest steps such as spawn production, substrate preparation, and the entire mushroom growth process, which includes substrate colonization, fruiting, harvesting, and, finally, the postharvest. While novel methodologies are being explored for maintaining quality and extending shelf-life, the evaluation of the environmental impact of the entire mushroom production to identify areas for improvement is needed. By integrating this knowledge, strategies can be developed for a more sustainable and circular approach to Pleurotus ostreatus mushroom cultivation, promoting environmental stewardship and long-term viability in this industry.

Antimicrobial and hydrophobic cellulose paper prepared by covalently attaching cinnamaldehyde for strawberries preservation

The demand for paper-based packaging materials as an alternative to incumbent disposable petroleum-derived polymers for food packaging applications is ever-growing. However, typical paper-based formats are not suitable for use in unconventional applications due to inherent limitations (e.g., excessive hydrophilicity, lack antimicrobial ability), and accordingly, enabling new capabilities is necessity. Herein, a simple and environmentally friendly strategy was proposed to introduce antimicrobial and hydrophobic functions to cellulose paper through successive chemical grafting of 3-aminopropyltriethoxysilane (APS) and cinnamaldehyde (CA). The results revealed that cellulose paper not only showed long-term antibacterial effect on different bacteria, but also inhibited a wide range of fungi. Encouragingly, the modified paper, which is fluorine-free, displays a high contact angle of 119.7°. Thus, even in the wet state, the modified paper can still maintain good mechanical strength. Meanwhile, the multifunctional composite papers have excellent biocompatibility and biodegradability. Compared with ordinary cellulose paper, multifunctional composite paper can effectively prolong the shelf life of strawberries. Therefore, the multifunctional composite paper represents good application potential as a fruit packaging material.

Recent advances and role of melatonin in post-harvest quality preservation of shiitake (Lentinula edodes)

Shiitake mushrooms are renowned for their popularity and robust nutritional value, are susceptible to spoilage due to their inherent biodegradability. Nevertheless, because of their lack of protection, these mushrooms have a short shelf life. Throughout the post-harvest phase, mushrooms experience a persistent decline in quality. This is evidenced by changes such as discoloration, reduced moisture content, texture changes, an increase in microbial count, and the depletion of nutrients and flavor. Ensuring postharvest quality preservation and prolonging mushroom shelf life necessitates the utilization of post-harvest preservation techniques, including physical, chemical, and thermal processes. This review provides a comprehensive overview of the deterioration processes affecting mushroom quality, covering elements such as moisture loss, discoloration, texture alterations, increased microbial count, and the depletion of nutrients and flavor. It also explores the key factors influencing these processes, such as temperature, relative humidity, water activity, and respiration rate. Furthermore, the review delves into recent progress in preserving mushrooms through techniques such as drying, cooling, packaging, irradiation, washing, and coating.

Development and characterization of active poly (3-hydroxybutyrate) based composites with grapeseed oil and MgO nanoparticles for shelf-life extension of white button mushrooms (Agaricus bisporus)

Poly (3-hydroxybutyrate) (PHB) is undoubtedly a potential substitute for petroleum-based non-biodegradable food packaging materials due to its renewability, high crystallinity, biocompatibility, and biodegradability. Nonetheless, PHB exhibits certain shortcomings, including low flexibility, moderate gas barrier properties, and negligible antimicrobial and antioxidant activities, which limit its direct application in food packaging. Loading essential oils can increase flexibility and induce antimicrobial and antioxidant activities in biopolymers but at the cost of reduced tensile strength. In contrast, nanofiller reinforcement can increase the tensile strength and barrier properties of such biopolymers. Therefore, to harness the synergistic effects of essential oil and nanofiller, PHB-based films incorporated with 5 wt% grapeseed oil (GS) and varying concentrations (0.1-1 wt%) of MgO nanoparticles (MgO NPs) were prepared in this study following simple sonication-assisted solution casting technique. Physicochemical, tensile, microstructural, optical, barrier, antimicrobial, and antioxidant properties were then evaluated for the prepared composite films. FESEM analysis of the PHB-based films with 5 wt% GS and 0.7 wt% MgO NPs (PHB/5GS/0.7MgO) confirmed its compact morphology without any aggregates, pores, or phase separation. In comparison with pristine PHB, the PHB/5GS/0.7MgO films demonstrated higher tensile strength (by 1.4-fold) and flexibility (by 30-fold), along with 79 and 90 % reduction in water vapor and oxygen transmission, respectively. In addition, PHB/5GS/0.7MgO showed good UV-blocking properties, 65.25 ± 0.98 % antioxidant activity, and completely inhibited the growth of Staphylococcus aureus and Escherichia coli. Moreover, PHB/5GS/0.7MgO films proved beneficial effects in terms of extending the shelf-life of white button mushrooms up to 6 days at ambient room conditions.

Enhancement of quality and self-defense capacity of Agaricus bisporus by UV-C treatment

BACKGROUND

Agaricus bisporus with a completely white appearance is popular with consumers. However, A. bisporus is susceptible to senescence and spoilage, which results in browning and oxidative tissue damage, with limited shelf life. This study investigated the effects of shortwave ultraviolet (UV-C, 1.0 kJ m-2 ) irradiation on quality features, enzymatic browning, and defense properties of A. bisporus stored at 4 °C for 21 days.

RESULTS

After storage, UV-C irradiated A. bisporus had increased quality of sensory, color and hardness characteristics; it exhibited higher content of total phenolic, brown melanin precursors, including γ-glutaminyl-4-hydroxybenzene, γ-glutaminyl-3,4-dihydroxybenzene and tyrosine, lower accumulation of malondiadehyde, hydrogen peroxide and superoxide radical, and maintained membrane integrity in comparison to control samples. Besides, A. bisporus treated by UV-C showed lower degree of browning and higher level of self-defense capacity, which may be ascribed to the enhancement in activities of superoxide dismutase, catalase, phenylalanine ammonia lyase, chitinase and β-1,3-glucanase activity, while inhibiting polyphenol oxidase activity during storage.

CONCLUSION

These results indicate that the higher self-defense capacity with UV-C treatment might be the mechanism associated with the delay of senescence in Agaricus bisporus. Therefore, UV-C treatment is suggested as a potential practical application in mushrooms. © 2023 Society of Chemical Industry.

Screening of Lactiplantibacillus plantarum NML21 and Its Maintenance on Postharvest Quality of Agaricus bisporus through Anti-Browning and Mitigation of Oxidative Damage

Browning and other undesirable effects on Agaricus bisporus (A. bisporus) during storage seriously affect its commercial value. In this study, a strain, Lactiplantibacillus plantarum NML21, that resists browning and delays the deterioration of A. bisporus was screened among 72 strains of lactic acid bacteria (LAB), and its preservative effect was analyzed. The results demonstrated that gallic acid, catechin, and protocatechuic acid promoted the growth of NML21, and the strain conversion rates of gallic acid and protocatechuic acid reached 97.16% and 95.85%, respectively. During a 15 d storage of the samples, the NML21 treatment displayed a reduction in the browning index (58.4), weight loss (2.64%), respiration rate (325.45 mg kg-1 h-1), and firmness (0.65 N). The treatment further inhibited Pseudomonas spp. growth and polyphenol oxidase activity, improved the antioxidant capacity, reduced the accumulation of reactive oxygen species, and reduced the malonaldehyde content and cell membrane conductivity. Taken together, the optimized concentrations of NML21 may extend the shelf life of A. bisporus for 3-6 d and could be a useful technique for preserving fresh produce.

Influence of Storage Temperature on Levels of Bioactive Compounds in Shiitake Mushrooms (Lentinula edodes)

Shiitake mushroom (Lentinula edodes) hold high nutritional and medicinal value as they contain an abundance of health-promoting compounds. However, the effect of long-term postharvest storage on the variation in the levels of health-promoting compounds has not been extensively studied. In this study, we investigated the changes in the levels of phenolic compounds, antioxidants, eritadenine, and ergothioneine in shiitake mushrooms stored at three different temperatures (1, 3, and 5 °C) for 4 weeks. Compared to mushrooms stored at lower temperatures, those stored at 5 °C exhibited a higher level of total phenolics in their pileus after 2 weeks of storage; however, storage at 5 °C also increased the deterioration of the fruiting body of these mushrooms. In mushrooms stored at all temperatures, the eritadenine content in the pilei tended to increase up to 2 weeks of storage. In contrast, the ergothioneine content in the pileus decreased during storage, with a significantly lower level detected in mushrooms stored at 5 °C for 4 weeks. Together, these results suggest that the mechanisms underlying the accumulation of phenolics and eritadenine may be related to mushroom deterioration during storage. Our findings indicate that the levels of health-promoting compounds in shiitake mushrooms are influenced by storage temperature, suggesting the potential to control adjustments of specific bioactive compounds by regulating storage conditions.

LC/MS- and GC/MS-based metabolomic profiling to determine changes in flavor quality and bioactive components of Phlebopus portentosus under low-temperature storage

Introduction

Low temperature is the most common method used to maintain the freshness of Phlebopus portentosus during long-distance transportation. However, there is no information regarding the nutritional changes that occur in P. portentosus preserved postharvest in low temperature.

Methods

In this study, the changes in flavor quality and bioactive components in fruiting bodies stored at 4 °C for different storage periods were determined through LC/MS and GC/MS analyses. Sampling was performed at 0, 3, 5, 7, and 13 days storage.

Results and Discussion

Based on the results, the metabolites present in caps and stipes were different at the same period and significantly different after 7 days of storage. A total of 583 and 500 different metabolites were detected in caps and stipes, respectively, and were mainly lipids and lipid-like molecules, organic acids and derivatives, organic oxygen compounds and others. Except for prenol lipids and nucleotides, the expression levels of most metabolites increased with longer storage time. In addition, geosmin was identified as the major contributor to earthy-musty odors, and the level of geosmin was increased when the storage time was short.

Conclusion

The variations in these metabolites might cause changes in flavor quality and bioactive components in P. portentosus. Variations in these metabolites were thoroughly analyzed, and the results revealed how storage processes affect the postharvest quality of P. portentosus for the first time.

Effect of nanopackaging on the quality of edible mushrooms and its action mechanism: A review

With higher demands for food packaging and the development of nanotechnology, nanopackaging is becoming a research hotspot in the field of food packaging because of its superb preservation effect, and it can effectively resist oxidation and regulates energy metabolism to maintain the quality and prolong the shelf life of mushrooms. Furthermore, under the background of SARS-CoV-2 pandemic, nanomaterials could be a potential tool to prevent virus transmission because of their excellent antiviral activities. However, the investigation and application of nanopackaging are facing many challenges including costs, environmental pollution, poor in-depth genetic research for mechanisms and so on. This article reviews the preservation effect and mechanisms of nanopackaging on the quality of mushrooms and discusses the trends and challenges of using these materials in food packaging technologies with the focus on nanotechnology and based on recent studies.

Emerging technologies for preservation and quality evaluation of postharvest edible mushrooms: A review

Edible mushrooms are the highly demanded foods of which production and consumption have been steadily increasing globally. Owing to the quality loss and short shelf-life in harvested mushrooms, it is necessary for the implementation of effective preservation and intelligent evaluation technologies to alleviate this issue. The aim of this review was to analyze the development and innovation thematic lines, topics, and trends by bibliometric analysis and review of the literature methods. The challenges faced in researching these topics were proposed and the mechanisms of quality loss in mushrooms during storage were updated. This review summarized the effects of chemical processing (antioxidants, ozone, and coatings), physical treatments (non-thermal plasma, packaging and latent thermal storage) and other emerging application on the quality of fresh mushrooms while discussing the efficiency in extending the shelf-life. It also discussed the emerging evaluation techniques based on the various chemometric methods and computer vision system in monitoring the freshness and predicting the shelf-life of mushrooms which have been developed. Preservation technology optimization and dynamic quality evaluation are vital for achieving mushroom quality control. This review can provide a comprehensive research reference for reducing mushroom quality loss and extending shelf-life, along with optimizing efficiency of storage and transportation operations.

Evaluation the effects of temperature and packaging conditions on the quality of button mushroom during storage using e-nose system

In this study, the effects of different packaging conditions on the quality of button mushrooms and some its chemical properties (pH and TSS) using an e-nose system equipped with ten sensors have been investigated. The button mushrooms were packaged using two types of films in two atmospheric modes. They were stored at 25 and 4 °C for ten days. During the storage, they were tested every other day. The results showed a mild increase in pH levels in all treatments during the ten days. Changes in TSS in ordinary polyethylene film-packed samples and ambient atmosphere at room temperature showed the highest value. Moreover, investigating the sensor response during the storage period showed that the most significant changes in the response of all sensors occurred in samples packed with polyethylene film and ambient atmosphere at 25 °C. Also, the scoring diagram of principal component analysis (PCA) showed that the completely distinct groups were detectable at two temperatures, two packaging films, and two different packaging atmosphere. At the same time, there was an overlap between the groups in six storage times. The support vector machine (SVM-C) and artificial neural network (ANN)classified the samples with 81 and 66% accuracy in six different storage times. The values of R 2 for predicting TSS and pH using PLS (partial least squares regression), MLR (multiple linear regression) and PCR (principal component regression) ranged between 51 and 68 and 54-59%, respectively, however prediction of TSS had a higher accuracy.

Graphical abstract

Improving the nutritional quality and bio-ingredients of stored white mushrooms using gamma irradiation and essential oils fumigation

Mushrooms are highly perishable in nature and deteriorate within a few days after harvesting due to their high respiration rate and delicate epidermal structure. Consequently, the shelf-life of freshly harvested mushroom is limited to 1–3 days at ambient condition. Hence, the current investigation was carried out to study γ-irradiation effects (1.5 and 2.0 kGy) and essential oils (EOs) fumigation including geranium (60 and 80 μL/L) and lemongrass (40 and 60 μL/L) on nutritional quality (Vitamins C and D2) as well as bio-ingredients such as total soluble proteins, phenolic and flavonoids contents, antioxidant activity were determined as an origin of potential natural antioxidant plus the profile of phenols and flavonoids identified by HPLC. As well as activities of some enzymes (PPO, SOD, PAL, and APX) of Agaricus bisporus mushroom at 4 °C during storage time for twelve days. The findings showed that there was a reduction in the contents of Vit. C and vitamin D2 in all mushroom samples during storage, where the essential oil treatment especially 60 μL/L of geranium and 40 μL/L of lemongrass gave the least decrease (3.42 and 3.28 mg/100 g FW, respectively) of ascorbic acid content compared to the other treatments while the irradiated samples (1.5, and 2.0 kGy) gave the lowest decrease of vitamin D2 (106.30 and 114.40 mg/kg DW, respectively) at the end of storage time. The content of the bio-ingredients content was affected by the storage periods, and the samples treated with oil fumigation gave the best content and the same trend happened with the antioxidant activity. The enzymes activity increased by the storage period, especially after 4 days of storage, and then the activity decreased after that. Quantification of phenolic and flavonoid compounds affected by storage periods in all treatments and the EO-treated mushrooms gave the best amount of them. Thus, samples of mushrooms treated with oil fumigation especially 60 μL/L of geranium and 40 μL/L of lemongrass can successfully increase the nutritional value plus maintain the value of the mushrooms during storage time.

One-Step Synthesis of Poly(L-Lactic Acid)-Based Soft Films with Gas Permselectivity for White Mushrooms (Agaricus bisporus) Preservation

Proper packaging can extend the shelf life and maintain the quality of mushrooms during storage. The purpose of this study is to investigate the preservation of Agaricus bisporus using copolymer-modified poly (L-lactide-co-butylene fumarate) and poly (L-lactide-co-glycolic acid) (PLBF and PLGA) packaging. Shelf life and quality were evaluated over 15 days of storage of Agaricus bisporus at 4 ± 1 °C and 90% relative humidity, including weight loss, browning index (BI), total phenolics (TP), ascorbic acid (AA), malondialdehyde content (MDA), electrolyte leakage rate (EC), and superoxide dismutase (SOD) and catalase (CAT). The results showed that mushrooms packaged in PLBF films exhibited better retention in BI, TP, and AA than those with PLLA, PLGA, or polyethylene (PE) films. They can reduce the rate of weight loss, EC, and MDA, which in turn increases the activity of SOD and CAT. PLBF and PLGA have substantially improved flexibility in comparison with PLLA. They also significantly reduced oxygen (O₂) and carbon dioxide (CO₂) permeability and changed the gas permeability ratio. These positive effects resulted in the effective restriction of O₂ and CO₂ in these packages, extending the post-harvest storage period of white mushrooms.

Nitric Oxide Made a Major Contribution to the Improvement of Quality in Button Mushrooms (Agaricus bisporus) by the Combined Treatment of Nitric Oxide with 1-MCP

Browning is one of the major effects of shelf-life responsible for the reduction in the commercial value of the button mushrooms (Agaricus bisporus). In this study, the individual and the combined effects of exogenous sodium nitroprusside (SNP, a nitric oxide donor) and 1-methylcyclopropene (1-MCP) on the quality of button mushrooms were evaluated. The results demonstrated that mushrooms treated with SNP+1-MCP promoted reactive oxygen species (ROS) metabolism thereby protecting cell membrane integrity, hindering polyphenol oxidase (PPO) binding to phenolic compounds, and downregulating the PPO activity. In addition, the SNP+1-MCP treatment effectively maintained quality (firmness, color, total phenol, and flavonoid) and mitigated oxidative damage by reducing ROS accumulation and malondialdehyde production through the stimulation of the antioxidant enzymes activities and the enhancement of ascorbic acid (AsA) and glutathione (GSH) contents. Moreover, the correlation analysis validated the above results. The SNP+1-MCP treatment was observed to be more prominent on maintaining quality than the individual effects of SNP followed by 1-MCP, suggesting that the combination of NO and 1-MCP had synergistic effects in retarding button mushrooms senescence, and NO signaling molecules might be predominant in the synergy.

Effect of Chitosan Nanoparticles as Edible Coating on the Storability and Quality of Apricot Fruits

Apricots are a fragile fruit that rots quickly after harvest. Therefore, they have a short shelf-life. The purpose of this work is to determine the effect of coatings containing chitosan (CH) as well as its nanoparticles (CHNPs) as thin films on the quality and shelf-life of apricots stored at room (25 ± 3 °C) and cold (5 ± 1 °C) temperatures. The physical, chemical, and sensorial changes that occurred during storage were assessed, and the shelf-life was estimated. Transmission electron microscopy was used to examine the size and shape of the nanoparticle. The nanoparticles had a spherical shape with an average diameter of 16.4 nm. During the storage of the apricots, those treated with CHNPs showed an obvious decrease in weight loss, decay percent, total soluble solids, and lipid peroxidation, whereas total acidity, ascorbic acid, and carotenoid content were higher than those in the fruits treated with CH and the untreated fruits (control). The findings of the sensory evaluation revealed a significant difference in the overall acceptability scores between the samples treated with CHNPs and the other samples. Finally, it was found that CHNP coatings improved the qualitative features of the apricots and extended their shelf-life for up to 9 days at room temperature storage and for 30 days in cold storage.

Effect of Silver Nitrate (AgNO3) and Nano-Silver (Ag-NPs) on Physiological Characteristics of Grapes and Quality during Storage Period

The aim of this study was to evaluate the effects of silver nitrate (AgNO3) and nano-silver (Ag-NPs) on the physiological and biochemical characteristics, and quality of grape bunches during a cold storage period. For investigations, two varieties of grapes were used, Shine Muscat and Kyoho, with different concentrations of AgNO3 and Ag-NPs on post-harvest dipping. The data indicated that AgNO3 and Ag-NPs enhanced the fruits’ longevity and quality. Depending on the data analysis, it was found that the lowest weight loss value was obtained from Ag-NP treated grapes, followed by AgNO3 treated grapes, while the highest loss occurred in the control grapes. Immersion of grape bunches in Ag-NPs was the best application for maintenance of overall storage quality for both cultivars. In the same trend, treatment with Ag-NPs produced the best results for soluble solids content (SSC), titratable acidity (TA), malondialdehyde (MDA) content, polyphenol oxidase (PPO), pyrogallol peroxidase (POD), and pectin methylestraese activity (PME). It was concluded that Ag-NPs and AgNO3 were helpful in maintaining the quality of grape bunches up to 30 days, while grape bunches under control conditions were spoiled with 30 days of cold storage.

Non-destructive assessment of quality parameters of white button mushrooms (Agaricus bisporus) using image processing techniques

Considering that appearance of white button mushroom (WBM) as the trigger for registering its quality, this study was aimed at analyzing the visual cues by the application of image processing tools. While L-a-b colour space and skewness was used for estimating chromatic and morphological characteristics; onset of discolouration of WBM was predicted by hyperspectral image analysis. Undamaged (UD) and damaged (D) mushrooms were stored under refrigerated conditions (3-5 °C and 90% R_h). RGB and hyperspectral images were acquired on alternate storage days 1, 3, 5, 7 and 9. Weight loss, texture and moisture content of stored mushrooms were also recorded during the storage period. Colour changes in stored UD and D were found to be in b (21.55) and a (2399) value, respectively. Browning index in D was 83-212% higher than UD mushrooms across the storage period. Weight and firmness losses in D were higher by 65.9 and 31.4%, respectively than UD. Morphological characteristic in terms of aspect ratio and roundness were not found to vary significantly over the storage period for both UD and D mushrooms. Chemometrics revealed that multiplicative scatter correction was the best pre-processing tool and that onset on discolouration is conspicuous in the spectral region of 520-800 nm. k-NN fared better than PLS-DA for correct classification (100%) of UD and D mushrooms.

Influence of biopolymer coatings on the storage stability of osmotically dehydrated mushrooms

The main aim of this research was to apply biopolymer coatings on osmotically dehydrated mushrooms and monitor their quality during storage. Mushrooms were osmotically dehydrated in sugar beet molasses (80% dry matter) under optimized conditions (45 °C for 5 hours), as previously reported elsewhere. Two different biopolymers were chosen: chitosan, a polysaccharide polymer, and zein, a protein polymer. A non-treated mushroom sample was chosen as a control sample. The mushroom samples were analysed for sugar and protein content, as well as water loss and microbiological profile. An increase in sugar content was the most noticeable in the osmotically dehydrated mushrooms compared to the control sample due to the use of molasses as a hypertonic solution. The contribution of used biopolymer coatings to the sugar and protein content of the coated and osmotically treated mushrooms was negligible. Chitosan coating contributed to better storage stability of treated mushrooms by lowering the moisture loss and microbial count. For this reason, chitosan treated sample was chosen for further examination related to the evaluation of its baking potential as a filling in a traditional stuffed pie-like layered bakery product - burek. Burek was stuffed with fresh mushrooms, osmotically treated mushrooms or osmotically treated mushrooms coated with chitosan. The sensorial assessment proved that control burek and burek samples with osmotically dehydrated mushrooms coated with chitosan were the most preferred groups based on odour and overall impression.

Influence of biopolymer coatings on the storage stability of osmotically dehydrated mushrooms

The main aim of this research was to apply biopolymer coatings on osmotically dehydrated mushrooms and monitor their quality during storage. Mushrooms were osmotically dehydrated in sugar beet molasses (80% dry matter) under optimized conditions (45 °C for 5 hours), as previously reported elsewhere. Two different biopolymers were chosen: chitosan, a polysaccharide polymer, and zein, a protein polymer. A non-treated mushroom sample was chosen as a control sample. The mushroom samples were analysed for sugar and protein content, as well as water loss and microbiological profile. An increase in sugar content was the most noticeable in the osmotically dehydrated mushrooms compared to the control sample due to the use of molasses as a hypertonic solution. The contribution of used biopolymer coatings to the sugar and protein content of the coated and osmotically treated mushrooms was negligible. Chitosan coating contributed to better storage stability of treated mushrooms by lowering the moisture loss and microbial count. For this reason, chitosan treated sample was chosen for further examination related to the evaluation of its baking potential as a filling in a traditional stuffed pie-like layered bakery product-burek. Burek was stuffed with fresh mushrooms, osmotically treated mushrooms or osmotically treated mushrooms coated with chitosan. The sensorial assessment proved that control burek and burek samples with osmotically dehydrated mushrooms coated with chitosan were the most preferred groups based on odour and overall impression.

Preparation and characterization of chitosan/zein film loaded with lemon essential oil: Effects on postharvest quality of mushroom (Agaricus bisporus)

In this study, different concentrations of lemon essential oils (LEO) were incorporated into chitosan/zein complex film (C/Z/L films) to improve its antioxidant and antimicrobial capacity, and the effects of C/Z/L films on mushroom quality were evaluated at 4 °C for 12 d. The antioxidant and antimicrobial activity of C/Z films were effectively improved by addition of LEO in a concentration-dependent manner. What's more, EAB value and gas permeability increased while TS value and water vapor permeability decreased upon the gradual increase of LEO content. During the entire storage, C/Z/L films were effective in suppressing PPO and POD activity of mushrooms as well as inhibiting the growth of microorganism. Mushrooms packaged with the film containing 6% LEO showed the lowest browning index and respiration rate. In addition, the C/Z/L film-treated mushrooms exhibited higher antioxidant capacity and more satisfactory texture properties. The results of our study presented that C/Z active film loaded with LEO could be used to maintain the postharvest quality of mushrooms.

The effect of carbon dioxide on the quality of the mushrooms

Mushrooms' quality may be significantly changing depending on their type, strain, growing cycle, packing, cooling, postharvest handling (PHH), and conditions of storage. This work aimed to define the influence of the type and mushrooms' strain, the regime of the PHH by carbon dioxide on their preservation (marketability, loss of weight (LW)), changes in the chemical substances, and physiological activity (intensity respiration (IR) and heat release (HR)). Mushrooms Agaricus bisporus (AB) (strains ІБК-25 and ІБК-15) and Pleurotus ostreatus (PO) (strains НК-35 and Amycel 3000) were used for testing. Three regimes of treatment by CO2 with a concentration of 20% were applied: 2 h; 12 h and 22 h. The control was the mushrooms without treatment by CO2. Changes in the chemical substances such as dry matters (DM), protein nitrogen (PN), and ascorbic acid (AA) in the researched mushrooms were observed. The best result of mushroom preservation was provided by the regime of CO2 treatment during 12 h. The yield of marketable AB was 94.9% (IBK-25) and 94.2% (IBK-15) comparison to control 93.5%, and 92.5%, respectively. The regime of PHH 2 h almost has no influence but 22 h harmed this indicator. PHH of mushrooms by carbon dioxide was promoted to preserve the DM and increasing concentration of CO2 was supplied better results. Thus, DM at the end of storage in the AB of strain IBK-25 depend on the regime were 8.5, 8.6, and 8.4%, against – 8.3% in the control variant. Significant quantitative changes in the PN and AA as a result of treatment by CO2 were not established. PHH also affected the IR and HR. The increased duration of treatment by CO2 inhibited the intensity of physiological processes in the mushrooms. But, as in previous cases, the best result was provided PHH by 20% CO2 during 12 h. Similar trends of treatments effect by carbon dioxide were observed in the mushrooms of PO.

Bioactive components of mushrooms: Processing effects and health benefits

Mushrooms have been recognized for their culinary attributes for long and were relished in the most influential civilizations in history. Currently, they are the focus of renewed research because of their therapeutic abilities. Nutritional benefits from mushrooms are in the form of a significant source of essential proteins, dietary non-digestible carbohydrates, unsaturated fats, minerals, as well as various vitamins, which have enhanced its consumption, and also resulted in the development of various processed mushroom products. Mushrooms are also a crucial ingredient in traditional medicine for their healing potential and curative properties. The literature on the nutritional, nutraceutical, and therapeutic potential of mushrooms, and their use as functional foods for the maintenance of health was reviewed, and the available literature indicates the enormous potential of the bioactive compounds present in mushrooms. Future research should be focused on the development of processes to retain the mushroom bioactive components, and valorization of waste generated during processing. Further, the mechanisms of action of mushroom bioactive components should be studied in detail to delineate their diverse roles and functions in the prevention and treatment of several diseases.

Development of Active Packaging to Extend the Shelf Life of Agaricus bisporus by Using Plasma Technology

In this study, a preservation package that can extend the shelf life of Agaricus bisporus was developed using plasma modification combined with low-density polyethylene (LDPE), collagen (COL), and carboxymethyl cellulose (CMC). Out results showed that the selectivity of LDPE to gas can be controlled by plasma modification combined with coating of different concentrations of CMC and COL. Packaging test results applied to A. bisporus showed that 3% and 5% of CMC and COL did not significantly inhibit polyphenol oxidase and β-1,3-glucanase, indicating no significant effect on structural integrity and oxidative browning. The use of 0.5% and 1.0% CMC and COL can effectively inhibit the polyphenol oxidase and β-1,3-glucanase activity of A. bisporus, leading to improved effects in browning inhibition and structural integrity maintenance. P-1.0COL can effectively maintain gas composition in the package (carbon dioxide: 10–15% and oxygen: 8–15%) and catalase activity during storage, thereby reducing the oxidative damage caused by respiration of A. bisporus. The current study confirmed that the use of plasma modification technology combined with 1.0% COL can be used in preservation packaging by regulating the respiration of A. bisporus, thus extending its shelf life from 7 to 21 days.

Structural and Functional Properties of Fluorinated Silica Hybrid Barrier Layers on Flexible Polymeric Foil

The reported work was focused on sol–gel-derived organically modified and fluorinated silica coatings deposited on elastic polymeric foil. The structure and topography of the coatings were tested by infrared spectroscopy and microscopic studies. The functional properties were determined using thermal analysis, surface analysis, and oxygen permeability tests. The barrier feature of the investigated materials against oxygen was correlated with the properties of the coatings. The hybrid (organic–inorganic) structure of the coatings was proven, demonstrating the presence of a silica network modified with alkyl and fluoroalkyl groups since precursors with the isooctyl group or different lengths of the fluoroalkyl chains were used for the syntheses. The coatings were free of defects and had a smooth surface except for the sample containing the longest fluoroalkyl chain (perfluorododecyl group), which showed a wrinkle-like surface. The hydrophobic character of the coatings increased, whereas the oxygen permeation coefficient values decreased (reaching a fourfold lower coefficient in comparison to the bare substrate) with a higher content of the fluorinated carbon atoms in the structure. The results were enriched by the information from the thermomechanical analysis as well as nanoindentation and scratch tests giving values of the glass transition temperature, thermal expansion coefficient, coatings adhesion, and hardness of the investigated systems.

Enhancement in physicochemical parameters and microbial populations of mushrooms as influenced by nano-coating treatments

White button mushrooms are greatly high perishable and can deteriorate within a few days after harvesting due to physicomechanical damage, respiration, microbial growth of the delicate epidermal structure. For that reason, the present research work was applied to evaluate the effect of chitosan combination with nano-coating treatments on physicochemical parameters and microbial populations on button mushrooms at chilling storage. Nano coating with the addition of nisin 1% (CHSSN/M) established the minimum value for weight loss 12.18%, maintained firmness 11.55 N, and color index profile. Moreover, O₂% rate of (CHSSN/M) mushrooms was the lowest at 1.78%; while the highest rate was reported for CO₂ 24.88% compared to the untreated samples (Control/M) on day 12. Both pH and total soluble solid concentrations increased during storage. Results reported that the (CHSS/M) mushroom significantly (P < 0.05) reduced polyphenol oxidase activity (24.31 U mg^-1 Protein) compared with (Control/M) mushrooms that increased faster than the treated samples. (CHSSN/M) treatment was the most efficient in the reduction of yeast and mold, aerobic plate microorganisms (5.27-5.10 log CFU/g), respectively. The results established that nano-coating film might delay the aging degree and accompany by marked prolongation of postharvest mushroom freshness.

The combined effect of coating treatments to nisin, nano-silica, and chitosan on oxidation processes of stored button mushrooms at 4 °C

Agaricus bisporus is an edible fungus with a limited shelf life due to high moisture loss, browning, respiration, self-dissolve, lack of physical protection, rotting, and microbial attack. Mushrooms have been coated with nisin, nano-silica, and chitosan films in order to extend the shelf life, preserve quality and oxidation activities. The results showed that treating the mushrooms with chitosan and nano-silica (CH-AN-SILICA) increased superoxide dismutase activity (SOD—6.53 U kg⁻¹), total phenolic content (TPC—0.39 g kg⁻¹), and malondialdehyde content (MDA—1.63 µmol kg⁻¹). CH-AN-SILICA treatment exhibited the highest scavenging against 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals. While, CH-AN-SILICA with the addition of nisin as an antimicrobial agent preserved almost the reactive oxygen species such as hydroxyl radicals (OH—0.33 µmol g⁻¹), superoxide anion (O₂^•−—0.271 mmol s⁻¹ kg⁻¹), and hydrogen peroxide (H₂O₂—21.54 µmol g⁻¹). Besides, both CH-AN-SILICA and CH-AN-SILICA/N enhanced the catalase (CAT) activity and reduced the respiration rate. The results indicated that the combination of nisin, nano-silica, and chitosan coating films was effective in providing a longer storage life with acceptable quality in mushrooms.