Development of shelf-life kinetic model for modified atmosphere packaging of fresh sliced mushrooms

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.

The improvement of freezing time and functional quality of frozen mushrooms by application of probe-type power ultrasound

The study proposes a novel ultrasound-assisted freezing method for button mushrooms, which combines probe-type ultrasonication and immersion freezing. The effects of power ultrasound in both continuous and pulse modes (at five levels of 50, 100, 200, 300, and 400 W) on the freezing process and quality attributes of frozen mushrooms were investigated. Results showed that ultrasound-assisted freezing significantly reduced freezing time compared to immersion freezing, potentially due to the formation of abundant cavitation bubbles that enhanced heat and mass transfer rates. The lowest weight loss was achieved by the continuous mode of 200 W ultrasound (UC200), which may be attributed to the formation of smaller ice crystals during ultrasonication. Ultrasound also prevented acidification and resulted in the retention of the samples' pH and higher total solid solution than immersion freezing. The optimal ultrasound power and duty cycle for different freezing outcomes were determined using the TOPSIS method. UC200 was found to be the best treatment for total freezing time and minimizing weight loss, while a combination of UC200 and UC400 was optimal for gumminess and chewiness. The proposed ultrasound-assisted freezing method shows promise as an environmentally friendly and safe technique for commercial use in the future.

Effect of Ultrasound Pretreatment on the Moisture Migration and Quality of Cantharellus cibarius Following Hot Air Drying

The effect of different ultrasound pretreatment powers (0-500 W) before hot air drying on the moisture migration and quality of Cantharellus cibarius (C. cibarius) was investigated in this study. The results showed that the ultrasound pretreatment accelerated the drying rate. When the ultrasound power was 400 W, the drying time of C. cibarius was reduced by 18.90% compared with the control group. The low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) results showed that the ultrasound pretreatment increased the water mobility in C. cibarius. The scanning electron microscopy (SEM) results revealed that the ultrasound pretreatment promoted the expansion of intercellular pores. In addition, the rehydration capacity and quality characteristics of the ultrasound-pretreated dried C. cibarius were better than those of the control group. Overall, this study concluded that ultrasound pretreatment is a promising pretreatment method for the hot air drying of C. cibarius products to reduce the total drying time significantly and improve the retention rate of the total phenolics and flavonoids of dried C. cibarius.

Enhancing Shelf Life Prediction of Fresh Pizza with Regression Models and Low Cost Sensors

The waste of food presents a challenge for achieving a sustainable world. In Germany alone, over 10 million tonnes of food are discarded annually, with a worldwide total exceeding 1.3 billion tonnes. A significant contributor to this issue are consumers throwing away still edible food due to the expiration of its best-before date. Best-before dates currently include large safety margins, but more precise and cost effective prediction techniques are required. To address this challenge, research was conducted on low-cost sensors and machine learning techniques were developed to predict the spoilage of fresh pizza. The findings indicate that combining a gas sensor, such as volatile organic compounds or carbon dioxide, with a random forest or extreme gradient boosting regressor can accurately predict the day of spoilage. This provides a more accurate and cost-efficient alternative to current best-before date determination methods, reducing food waste, saving resources, and improving food safety by reducing the risk of consumers consuming spoiled food.

Shelf Life Prediction and Kinetics of Quality Changes in Pineapple (Ananas comosus) Varieties at Different Storage Temperatures

Shelf life estimation is an important factor to predict the freshness of fruits. This study aimed to investigate the shelf life and the changes in the physicochemical properties of three different pineapple varieties, namely MD2, Josapine, and Morris stored at 5, 10, and 25 °C. The effect of storage temperature on pineapple changes in total soluble solids, pH, moisture content, firmness, and colour was evaluated for 21 days of the storage period. It was revealed that different storage temperatures have a significant effect on the shelf life and quality of different pineapple varieties. The firmness and moisture content showed high regression coefficients, hence were used for the shelf life prediction of pineapple based on kinetic models. By using first-order kinetics, the coefficient of determination (R2) values for quality changes in pineapples ranged from 0.893 to 0.992. The results also demonstrated that the samples stored at 10 °C had the longest shelf life in relation to the changes in firmness and moisture content of the fruit. The findings indicated that shelf life estimation plays an important role to improve the quality preservation of fresh fruits and vegetables during storage.

Pretreatment with high oxygen controlled atmosphere enhanced fresh-cut white mushroom (Agaricus bisporus) quality via activating wounding stress defenses

BACKGROUND

High oxygen treatment has been proven to be effective in fresh-cut white mushroom preservation, however, the preservation effect and possible mechanisms in high oxygen controlled atmosphere pretreatment (HOCAP) on wounding stress are incompletely understood.

RESULTS

In this study, based on the time chosen of HOCAP research, whole white mushrooms treated with 3 h HOCAP (80% O₂  + 20% CO₂ ) and the wounding resistant responses of their slices were mainly investigated through phenylpropane pathway, reactive oxygen species (ROS) scavenging system, and ascorbate-glutathione (AsA-GSH) cycle. Results showed that 3 h HOCAP can induce the production of hydrogen peroxide (H₂ O₂ ) and superoxide anion (O₂ ^-• ) in the early stage, as well as the NADPH oxidase activity. Enzymes and endogenous antioxidants involved in ROS scavenging were enhanced by HOCAP during the whole storage. Besides, HOCAP maintained high level of phenylalanine ammonia-lyase (PAL) activity, enhanced the content of total phenolic and lignin, accelerated the AsA-GSH cycle.

CONCLUSION

The results demonstrated that HOCAP induced defense responses by increasing the ROS in the early stage which stimulated the activities of ROS scavenging enzymes, along with the capability of increasing for wounding stress defense and resistance. This study provides a theoretical pretreatment technology for fresh-cut white mushroom preservation. © 2021 Society of Chemical Industry.

Effect of Antibacterial Peptide Microsphere Coating on the Microbial and Physicochemical Characteristics of Tricholoma matsutake during Cold Storage

The effect of novel antimicrobial peptides (AMPs) and antimicrobial peptide microspheres (AMS) on the physicochemical and microbial quality of Tricholoma matsutake wild edible mushrooms was investigated. In the experiments, 1.0 g/L, 0.5 g/L of AMS, and 1.0 g/L AMPs were used as preservatives. Mushrooms coated with 1.0 g/L and 0.5 g/L of AMS as a preservative had better physicochemical and sensory qualities than did mushrooms coated with 1.0 g/L of AMPs. In the experiment, 1.0 g/L of blank microspheres without cathelicidin-BF-30 (PLGA-1.0) and distilled water was used as the control. Samples with these two treatments had minimal changes in texture, weight loss, total bacteria count, and sensory attributes. Research results suggests that the use of AMS can maintain the quality of Tricholoma matsutake wild edible mushrooms and could extend the postharvest life to 20 d.

Fresh Mushroom Preservation Techniques

The production and consumption of fresh mushrooms has experienced a significant increase in recent decades. This trend has been driven mainly by their nutritional value and by the presence of bioactive and nutraceutical components that are associated with health benefits, which has led some to consider them a functional food. Mushrooms represent an attractive food for vegetarian and vegan consumers due to their high contents of high-biological-value proteins and vitamin D. However, due to their high respiratory rate, high water content, and lack of a cuticular structure, mushrooms rapidly lose quality and have a short shelf life after harvest, which limits their commercialization in the fresh state. Several traditional preservation methods are used to maintain their quality and extend their shelf life. This article reviews some preservation methods that are commonly used to preserve fresh mushrooms and promising new preservation techniques, highlighting the use of new packaging systems and regulations aimed at the development of more sustainable packaging.

Variation in cell membrane integrity and enzyme activity of the button mushroom (Agaricus bisporus) during storage and transportation

Button mushrooms (Agaricus bisporus) were put under stimulated storage and transportation environments with different amounts of phase-change materials (PCM). Results showed that the addition of PCM effectively maintained a cooler environment and delayed a rise in temperature. And the addition of PCM, especially in a ratio 1:2 PCM:mushroom, had a significant effect on delaying the increase in cell membrane permeability, malondialdehyde and H2O2 levels, and also delayed superoxide dismutase and catalase activity. These results suggest that PCM may be candidate in postharvest mushroom during storage and transportation.

The combined impact of calcium lactate with cysteine pretreatment and perforation-mediated modified atmosphere packaging on quality preservation of fresh-cut 'Romaine' lettuce

The effect of perforation-mediated modified atmosphere packaging (PM-MAP) in combination with calcium lactate (1.5% CaL) and cysteine (0.1, 0.5% Cys) immersion pretreatments on the quality preservation of fresh-cut 'Romaine' lettuce was assessed for 12 days, at 5 and 10 °C. The shredded lettuce was packed in low-density polyethylene films (LDPE, 62 µm thickness), including different perforation numbers of 0 (N-MAP), 20 (20-PM-MAP, Diameter = 64 µm), and 40 (40-PM-MAP, Diameter = 64µm) per in square meter. Indices of quality maintenance were investigated. The total microbial counts were below the specified limits for ready-to-eat vegetables (< 6 log CFU/g) considering both pretreated 20-PM-MAP and N-MAP samples on day 12. After 8 days, a significant difference (P < 0.05) was observed in the browning index (BI), the total color difference (ΔE), and the chlorophyll content between N-MAP and 20-PM-MAP samples with better results in 20-PM-MA packages. At 10 °C, the BI in pretreated 20-PM-MAP samples was 32.44% to 58.35% less than N-MAP samples, on the last day of storage. The 20-PM-MAP samples pretreated with 1.5% CaL/0.5% Cys had the highest (P < 0.05) crispness coefficient and water content values. It seems that packaging the pretreated lettuce in 20-PM-MA packages is more effective for maintaining the visual properties (green fresh appearance) of this product, from the 8th to the 12th day of storage. PRACTICAL APPLICATION: The medium to high respiration rate of fresh-cut lettuce causes O2 level drops below its tolerance limit (<1% to 3%) inside the modified atmosphere packaging (MAP). It results in severe browning, off-odors, off-flavor, and growth of anaerobiosis. Perforated-mediated modified atmosphere packaging (PM-MAP) technology can be introduced as an alternative to a nonperforated MAP system (conventional MAP) for fresh-cut lettuce. The application of the PM-MAP system in combination with calcium lactate and cysteine immersion pretreatment (CaL/Cys) may lead to better maintenance of the physicochemical properties of this product.

The microperforated packaging design and evaluation of shelf life of fresh-sliced mushrooms

Fresh mushrooms have a very short shelf life, of 1 – 3 days because of their high respiration rate and lack of cuticles that protect the plant from external factors. In the case of fresh-sliced mushrooms, they will be more susceptible to spoilage reactions due to the increase in respiration rate as a result of a broader surface area. Conventional packaging materials can not meet the requirements for modified atmosphere packaging of fresh-sliced mushrooms. One of the techniques to extend the fresh-cut produce shelf life is the passive modification of modified atmosphere packaging technology. For highly respiring fresh-cut produce such as fresh-sliced mushrooms, the permeability properties of the polymeric materials might not be enough to provide an equilibrium gas concentration in the passive modification of modified atmosphere technology. In this case, the microperforated packaging materials can be used for passive modification of fresh-cut produce. But the microperforation process needs a design for the application of the appropriate number and diameter of microholes to meet the requirements of passive modified atmosphere packaging. For this reason in this research, the design of the microperforation process to be used in passive modified atmosphere packaging was based on the diameter and the number of microholes, and the shelf life of fresh-sliced mushrooms was determined. The samples were stored at 15 °C/80% RH, and pH, color, weight loss, textural, sensorial, and microbial analysis were performed periodically during storage. It was determined that the empirical equation used in this research can be applied to microperforated packaging design for fresh-sliced mushrooms. The shelf life of the fresh-sliced mushrooms packaged with microperforated packaging material was 8 days, while it was less than 7 days (4, 5, or 6 days) when packaged with non-microperforated packaging material. This result shows that the use of microperforated packaging material is effective in extending the shelf life of fresh-sliced mushrooms.

Influence of cellulose nanocrystals gellan gum-based coating on color and respiration rate of Agaricus bisporus mushrooms

The edible coating has been used for covering fruits and vegetables, bringing surface protection, and extending product shelf-life. Due to the outstanding properties, nanomaterials have become a part of the packaging/coating new generation, demonstrating improvements in the barrier capacity of materials starting from construction products to the food industry. In the food industry, on the other hand, Agaricus bisporus mushrooms have a limited shelf-life from 1 to 3 days because of their high respiration rate and enzymatic browning. With the aim to reduce these two parameters and prevent rapid senescence, the objective of this study was to incorporate a natural source of nanomaterials (cellulose nanocrystals (CNCs) into a gellan gum-based coating and sprayed the surface of the mushrooms with the coating material. To evaluate the effect of CNCs, oxygen consumption, carbon dioxide production rate, and color change were recorded during the mushroom storage at 4 ± 1 °C. Results showed that all coatings were able to decrease total color change (ΔE) of mushrooms from 12 to 8 at day 10 when the coating was applied in all samples compared to control. In addition, significant differences were observed in the respiration rate when CNCs were added to the mushrooms. Oxygen consumption results exhibited a 44 mL O2 /kg · day production at day 5 with 20% CNCs compared to 269 mL O2 /kg · day observed in noncoated samples. This trend was similarly observed in the carbon dioxide production rate. PRACTICAL APPLICATION: With this research, it was remarkable to see the presence of CNCs in the coating solution reduced the respiration rate and increased the shelf-life of mushrooms. Similar applications can be industrially scaled-up to protect fruits and vegetables by CNCs-based coating or packaging materials. A variety of sustainable materials are available nowadays that serve as packaging matrix, and scientists are working on expanding the compatibility of these nanomaterials. In addition, it has been studied that CNCs enhance the degradation of polymers, an effort that many companies are making to reduce the environmental impact in their products.

Effects of long-term controlled atmosphere storage, minimal processing, and packaging on quality attributes of calçots (Allium cepa L.)

Calçots are the immature floral stems of the second-year onion (Allium cepa L.) resprouts. Modified atmosphere packaging or vacuum packaging are suitable alternatives to preserve fresh-cut vegetables. The objective of this study was to evaluate the effect of postharvest storage time of raw vegetable stored under controlled atmosphere and used packaging system after minimal processing on the quality of fresh-cut calçots. Calçots used for minimal processing were stored under 1.0 kPa O₂ + 2.0 kPa CO₂ at 1 ℃ for 30 and 60 days. Fresh-cut calçots were packaged using passive modified atmosphere packaging or vacuum packaging and were stored at 4 ℃ for 15 days. Calçots stored under controlled atmosphere for 30 days presented better retention of quality and in turn, being more suitable for minimally processing. Vacuum packaging preserved the physicochemical quality of fresh-cut calçots better after 15 days. Mesophilic aerobic counts were also higher in fresh-cut calçots stored under modified atmosphere packaging, but all counts were below the recommended limits during and at the end of their shelf-life (15 days). The most suitable conservation strategy might be to store whole calçots under controlled atmosphere for 30 days and after minimally processing, packaged under vacuum in order to extend the shelf-life of fresh-cut calçots.

Lactic Acid Fermentation of Edible Mushrooms: Tradition, Technology, Current State of Research: A Review

Pickling is one of the methods for preserving food. However, this term may refer to both types of products, that is, to those subjected to lactic acid fermentation and to marinated ones (acidified) that are usually produced by the addition of acetic acid. Various raw materials are subjected to lactic acid fermentation (vegetable and animal origin), which yields food products with high nutritional and dietary value. In many regions of the world, the process of lactic fermentation is also traditionally used to preserve fruiting bodies of edible mushrooms. Mushrooms are appreciated for their organoleptic qualities as well as the presence of many different bioactive substances exhibiting healing and health-promoting properties. This article reviews the literature related to the use of lactic fermentation in the process of mushroom preservation. Particular attention has been paid to the aspects of the technological process and its impact on the quality and suitability of the final products. Moreover, research results concerning the influence of lactic fermentation on chemical and physical changes in fruiting bodies of edible fungi are also presented.

Chitosan nanoparticles-loaded Citrus aurantium essential oil: a novel delivery system for preserving the postharvest quality of Agaricus bisporus

BACKGROUND

One of the main problems in the button mushroom industry is the rapid deterioration of fruit bodies after harvest. Today, nanotechnology has become a more reliable technique to improve the quality of products in food packaging. In the present study, the effectiveness of chitosan nanoparticles containing Citrus aurantium essential oil on postharvest quality of white button mushroom was examined and compared to essential oil fumigation and control treatments.

RESULTS

Based on high-resolution transmission electron microscopy and dynamic light scattering, nanoparticles exhibited a spherical shape of 20-60 nm diameter. The results revealed that the application of chitosan nanoparticles loaded with C. aurantium oil significantly decelerated the rate of color change, weight loss and firmness compared to fumigation with essential oil and control treatments. Treatment of fruit bodies with chitosan nanoparticles loaded with C. aurantium oil promoted the accumulation of phenolic compounds and ascorbic acid, and resulted in increases in catalase and superoxide dismutase and a decrease in polyphenol oxidase activities, as the highest antioxidant capacity was observed after 15 days of cold storage.

CONCLUSION

This present research demonstrates that gradual release of C. aurantium essential oil from chitosan nanoparticles could be an effective and practical method for extending the shelf life of white button mushroom up to 15 days without significant decrease in antioxidant capacity. © 2018 Society of Chemical Industry.

Shelf-life kinetic model for freeze-dried oranges using sensory analysis and luminance determination

Physical (luminance) and sensory variables (color and taste) were used to analyze the aging of freezed-dried oranges slices, determining the influence of temperature and time on aging and evaluating the shelf-life. The highest value in the luminance distribution curve, especially useful when the color of the food products is not uniform, and the color and taste scores obtained in sensory analysis were used to evaluate the shelf-life. Different kinetics models were probed to explain the experimental results but only third-order kinetic model correlated the luminance as a function of time and temperature. This kinetic constant obtained depended on the temperature following an Arrhenius model, giving an activation energy equal to 208 kJ/mol (R² = 0.9959). The correlation between physical (luminance) and sensory variables (color and taste) may be used to evaluate the shelf life of the orange slices, finding revealed that at 28 °C the shelf life may expected to be 10 years.

Total quality index of Agaricus bisporus mushrooms packed in modified atmosphere

BACKGROUND

The aim of this study was to develop a total quality index and examine the effects of modified atmosphere packaging (MAP) on the quality of Agaricus bisporus mushrooms stored for 22 days at 4 °C. Mushrooms were packaged under three MAPs: high nitrogen packaging (HNP), low carbon dioxide packaging (LCP) and low oxygen packaging (LOP). Passive MAP with air inside initially was used as the atmosphere treatment (AIR).

RESULTS

This research revealed two phases in quality deterioration of A. bisporus mushrooms. During the first week, most of the quality parameters were not statistically different. Thereafter, odor intensities were stronger for all four types of packaging. Color difference and browning index values showed significantly lower color changes for AIR and LOP compared with HNP and LCP mushrooms.

CONCLUSION

The best total quality index was calculated for LOP, followed by LCP and AIR. The findings of this study are useful with respect to examining two-component MAPs, separating the limiting factors (O₂ and CO₂ ) and evaluating quality deterioration effects and the total quality index of A. bisporus mushrooms. © 2016 Society of Chemical Industry.

Dehydration of Kiwifruit (Actinidia deliciosa) Slices Using Heat Pipe Combined with Impingement Technology

This study is designed to investigate drying kinetics, heating characteristics and energy consumption of heat pipe-impingement drying (HID) kiwifruit slices. Subsequently, color and rehydration characteristics of dried kiwifruit slices were also studied. The results showed that Modified Page model and trinomial regression equation provided appropriate fit for drying and heating curves of kiwifruit slices, respectively. In addition, the treatment for increasing drying temperatures and air velocities, and decreasing the distance between jet nozzles and material steel wire mesh box (DJM) was shown to enhance drying productivity. It was also found that low temperature, high air velocity and low DJM contributed to the processing of high-quality dried kiwifruit and the reduction of energy consumption. These results suggest that kiwifruit slices can be dried effectively with HID, and the predictive equations of heat and mass transfer could be applied to industrial design and operational guide for the HID of kiwifruit.

Effect of plasma activated water on the postharvest quality of button mushrooms, Agaricus bisporus

Non-thermal plasma is a new approach to improving microbiological safety while maintaining the sensory attributes of the treated foods. Recent research has reported that plasma activated water (PAW) can also efficiently inactivate a wide variety of microorganisms. This study invested the effects of plasma-activated water soaking on the postharvest preservation of button mushrooms (Agaricus bisporus) over seven days of storage at 20°C. Plasma activated water reduced the microbial counts by 1.5 log and 0.5 log for bacteria and fungi during storage, respectively. Furthermore, the corresponding physicochemical and biological properties were assessed between plasma activated water soaking groups and control groups. The results for firmness, respiration rate and relative electrical conductivity suggested that plasma activated water soaking can delay mushroom softening. Meanwhile, no significant change was observed in the color, pH, or antioxidant properties of A. bisporus treated with plasma activated water. Thus, plasma activated water soaking is a promising method for postharvest fresh-keeping of A. bisporus.