Modified Atmosphere Packaging Research Articles

Freshness prediction of modified atmosphere packaging lamb meat based on digital images from mobile portable devices

AbstractThis study aimed to quickly assess lamb meat freshness using smartphones under various modified atmosphere packaging and storage times (0–10 days). Lamb meat images were collected across different periods and packaging types (50% O2 + 40% CO2 + 10% N2; 70% O2 + 20% CO2 + 10% N2; air). Key color features were extracted, and significant differences in five color features were identified. Three distinct color feature combinations were chosen for models: support vector regression (SVR), genetic algorithm‐back propagation (GA‐BP) neural network, and convolutional neural network (CNN). Results showed SVR models with varied color feature inputs outperformed BP and CNN models. The SVR model with 12 input features yielded the best results, enabling effective spoilage level analysis of lamb meat under different storage times. This work establishes a foundation for future smartphone app development, utilizing Raspberry Pi hardware to evaluate lamb meat freshness under diverse storage conditions.Practical applicationsThis study introduces a cell phone‐based method to rapidly determine lamb spoilage in air conditioning packages during different storage times. Using cell phone images, we collected data on lamb samples stored for 0–10 days under three packaging conditions. We extracted significant color features and selected three combinations as inputs for prediction models: SVR, GA‐BP neural network, and CNN. The SVR model with 12 feature values demonstrated the best performance. This research lays the foundation for a cell phone application based on Raspberry Pi hardware, enabling users to assess lamb freshness in various storage conditions. The potential benefits include efficient quality control in the food industry, increased consumer confidence, and improved preservation of lamb products through optimized storage and packaging. Overall, this study contributes to food quality evaluation and provides practical applications for professionals and consumers.

Effect of Dielectric Barrier Discharge Cold Plasma on the Bio-nanocomposite Film and its Potential to Preserve the Quality of Strawberry under Modified Atmosphere Packaging

The present study aimed to investigate the effect of cold plasma on the developed bio-nanocomposite film. A dielectric barrier discharge system was utilized to generate the cold plasma. The films were treated under three different times (5, 10 and 15 min) and the characteristics of the films were evaluated. The cold plasma treatment influence the thermal stability and crystallization of the films. Results showed that the mechanical properties (tensile strength and elongation at break), water vapor permeability, oxygen transmission rate, moisture content and water contact angle characteristics were improved up to 69%, 31%, 34%, 3% and 28%, respectively by cold plasma treatment. In consequence, the average O2 and CO2 concentration of the packed strawberries decreased from 5 and 10% to 4.2% and 5.1%, respectively after 15 days. Finally, the results revealed that the mechanical properties, chemical attributes, physical characteristics and microbial activities of the samples were affected by the treated films. As a result, cold plasma modification can be applied as an effective method to maintain and preservation of fresh fruit.

Effect of CO2 on the preservation effectiveness of chilled fresh boneless beef knuckle in modified atmosphere packaging and microbial diversity analysis

To explore the effect of different concentrations of CO2 in modified atmosphere packaging (MAP) on the preservation shelf life of boneless beef knuckle (BBK), and to deeply study the changes in the bacterial community. In the controlled atmosphere combination, the proportion of O2 in each group is kept at 40%, CO2: 20%–45%, and N2: 15%–60%, the blank control group is set to 40%O2+0%CO2+60%N2. Sensory evaluation, headspace gas, total colony, and physicochemical indicators were measured at the 1st, 3rd, 5th, 7th, 9th, and 11th days of storage, respectively. The results showed that group 25%CO2+35%N2 had the longest shelf life is 9 days. In the analysis of the bacterial community, CO2 significantly inhibited the growth of Pseudomonas from the 3rd day onwards in the group 25%CO2+35%N2. After 4 days of storage, Lactobacillus was the main dominant bacterium, followed by Carnobacterium. Through KEGG metabolic pathway analysis, it was found that during the storage and preservation process, the expression levels of genes related to carbohydrate metabolism and amino acid metabolism in cold fresh BBK were higher than those in other metabolites.

Regulation of respiratory rate and storage quality of postharvest cauliflower based on gas permeability modification using gas barrier (GB) - gas conductor (GC) blending packaging

The aim of this work is to explore a method to develop equilibrium modified atmosphere packaging (EMAP) via density of available active site (AAS). Sulfonated poly etheretherketone (SPEEK) was prepared as a component to promote gas permeation, i.e. gas conductor (GC). It was mixed with polysulfone (PSF) as gas barrier (GB). With varying GC and GB concentrations, the prepared EMAP provided internal equilibrium atmospheres with 1.8% - 7.2% CO2 and 3.1% - 4.4% O2, in which respiratory rate of preserved cauliflower was inhibited and thereby the storage quality was maintained. Final sensory score of the cauliflower samples preserved in EMAP for 30 days was better than that of control samples (3.5 vs. 1.6), while the texture properties were maintained compared to those in the control samples. Additionally, the inhibitory effects were also shown in color parameters and chemical indicators. The findings in this work would promote the development of modified atmosphere packaging technology.

Modified Atmosphere Packaging Technology for Indonesian Food Products: The Latest Developments and Potentials

Modified Atmosphere Packaging Technology for Indonesian Food Products: The Latest Developments and Potentials

Fresh Insight: Enhancing Verdant Leafy Vegetable’s Shelf Life Via Modified Atmosphere Packing and Storage

This study aimed to enhance the durability of selected green leafy vegetables, including Lettuce and Palak, by manipulating influential factors such as storage conditions (Ambient (35±5°C) and Refrigerated (5±5°C)), packing substrate (Low-density polyethylene and High-density polyethylene covers), and gas composition using modified atmosphere packaging. Factorial completely randomized design (FCRD) was employed, incorporating a total of 12 treatments for each crop. The evaluation primarily relied on calculating physiological weight loss. Lettuce showed optimal results with treatment T5 (0.38%) exhibiting superior performance, followed by T6 (0.45%) and T3 (0.58%) under ambient conditions. Similarly, for palak, T5 (0.18%) outperformed T3 (0.19%) and T2 (0.37%). Thus, it is advisable to adopt T5 (R1G3M1) as the preferred treatment with T3 (R1G2M1) as a viable alternative for ambient storage conditions. Refrigerated lettuce performed optimally with T11 (0.54%) leading, followed by T7 (0.56%) and T9 (0.69%). Similarly, palak exhibited superior results with T9 (0.61%) in the fore, succeeded by T11 (0.77%) and T7 (0.97%). Notably, produce stored under ambient conditions had a relatively short shelf life of approximately 5 days, while refrigeration extended it to 15 days, after which a decline in quality was observed across all treatments. Therefore, refrigerated produce has an extended shelf life, with T9 (R2G2M1) followed by T7 (R2G1M1) yielding highly favorable outcomes.

Machine-Learning-Based Spectroscopic Technique for Non-Destructive Estimation of Shelf Life and Quality of Fresh Fruits Packaged under Modified Atmospheres

The safety and quality of fresh fruits deserve the greatest attention, and are a priority for producers and consumers alike. Modern technologies are crucial to accurately estimating and predicting fresh fruits’ quality and shelf life, to optimize supply chain management. Modified atmosphere packaging (MAP) is an essential method that maintains quality parameters and increases the shelf life of fresh fruits by reducing their ripening rates. This study aimed to develop a cost-effective, non-destructive technique using tiny machine learning (TinyML) and a multispectral sensor to predict/estimate the quality parameters and shelf life of packaged fresh dates under the natural atmosphere (Control), vacuum-sealed bags (VSBs), and MAP with different gas combinations: 20% CO2 + N balance (MAP1), and 20% CO2 + 10% O2 + N balance (MAP2). The shelf life and quality parameters of the packaged fresh dates (pH, total soluble solids (TSSs), sugar content (SC), moisture content (MC), and tannin content (TC)) were evaluated under different storage temperatures and times. A multispectral sensor (AS7265x) was utilized to correlate the fruit quality parameters with spectrum analysis under the same storage conditions, to prepare the dataset to train the prediction models. The prediction models were trained in the Edge Impulse Platform, and deployed to an Arduino Nano 33 BLE sense microcontroller unit (MCU) for inference. The findings indicated that the vacuum and MAP1 efficiently increased the shelf life and maintained the quality parameters of the packaged fresh fruit to 43 ± 2.39 and 39 ± 3.34 days, respectively, at 5 °C. The optimal neural network consisted of the input layer with 20 nodes (the packaging type, storage temperature, and 18 channels of the spectral sensor data at 410 to 940 nm wavelengths), two hidden layers with 20 and 12 nodes, and an output layer with one node for the target quality parameter or shelf life. These optimal prediction models efficiently predicted the shelf life with R2 = 0.951, pH with R2 = 0.854, TSSs with R2 = 0.893, SC with R2 = 0.881, MC with R2 = 0.941, and TC with R2 = 0.909. The evaluation of the developed prediction models under each packaging condition indicated that these models serve as powerful tools for accurately predicting fruit quality parameters, and estimating the shelf life of fresh dates.

A new strategy to design novel modified atmosphere packaging formulation maintains the qualities of postharvest strawberries (Fragaria ananassa) during low‐temperature storage

AbstractFor fresh foods, the purpose and benefits of modified atmosphere packaging (MAP) generally include the preservation of antioxidants, the extension of shelf life, deferral of microbial spoilage, and retention of product color. Commercial MAP products frequently involve a mixture of nitrogen, oxygen, and carbon dioxide, affecting consumer acceptability, cost‐effectiveness, and hygienic food safety issues. This study investigated a novel active MAP formulation for strawberries in retail packaging which ensures changes in quality‐related physicochemical characteristics [including hardness, moisture, vitamin C, total soluble solids (TSS), titratable acid, and appearance] during low‐temperature storage, whereas samples of different storage times were assessed for shelf life by sensory evaluation. The innovative active MAP formulation of 0.8 g of sodium ascorbate, 2.6 g of sodium carbonate, and 1.6 g of ferrous sulfate achieved atmosphere equilibrium in packaged strawberries in <48 h, compared to 5–6 days in the control group. Strawberries treated with active MAP maintained their moisture, firmness, vitamin C, TSS, and titratable acid contents better than the control group (p < 0.05). The strawberries showed softening and waterlogging of tissue and 50% moldiness by the 14th day, while the control group lost commercial value by the 8th. New applications of similar commodities in food are unavailable based on current knowledge. Therefore, the scope of fresh food applications covered in this study and the refinement of other functions will be helpful directions for future research.

Effect of Vacuum and Modified Atmosphere Packaging on the Shelf Life and Quality of Gutted Rainbow Trout (Oncorhynchus mykiss) during Refrigerated Storage.

The quality changes of gutted rainbow trout in vacuum packaging (VP) and modified atmosphere packaging (MAP) with 40% CO2 + 60% N2 (MAP1), 60% CO2 + 40% N2 (MAP2), and 90% CO2 + 10% N2 (MAP3) were evaluated. The samples were stored at 3 ± 0.5 °C, and on days 1, 4, 7, 10, 13, and 16 of storage, microbiological, chemical, and sensory testing was performed. The aerobic plate count (APC) and psychrotrophic bacteria count (PBC) in VP fish exceeded the conventional limit of 7 log cfu/g on day 10, and in MAP1 and MAP2 fish on day 16, whereas in MAP3 fish, their number remained below that limit during the experiment. MAP significantly slowed down the growth of Enterobacteriaceae in trout, and the degree of inhibition increased with increasing CO2 concentration in the gas mixture. The lowest lactic acid bacteria numbers were detected in VP fish, whereas the highest numbers were determined in trout packaged in MAP2 and MAP3. Significantly lower numbers of hydrogen sulfide-producing (H2S) bacteria were detected in fish packed in MAP. Distinct patterns were observed for pH among treatments. The lowest increase in TBARS values was detected in VP and MAP3 fish, whereas in MAP1 and MAP2 fish, the TBARS values were higher than 1 mg MDA/kg on day 16 of storage when a rancid odor was detected. MAP inhibited the increase in total volatile basic nitrogen (TVB-N) content of trout compared to trout packaged in a vacuum. The sensory attributes of trout perceived by the sensory panel changed significantly in all experimental groups during storage. Based primarily on sensory, but also microbial, and chemical parameters, MAP has great potential for preserving fish quality and extending the shelf life of gutted rainbow trout from 7 days in VP to 13 days in MAP1 and MAP2, and to 16 days in MAP3.

Ethanol fumigation combined with modified atmosphere packaging delays potato greening under light

Potato greening under light causes post-harvest loss and compromises progress being made in the potato industry. In this study, we investigated the inhibiting effects of ethanol fumigation treatment on potato greening and water loss under light. This paper also examined the different treatments on the relationship between starch granule size and potato greening. Our results suggested that ethanol fumigation combined with modified atmosphere packaging have an effective in improving the overall visual quality and maintained a higher a* value and lower chlorophyll concentration. Ethanol fumigation combined with modified atmosphere packaging treatment deterred greening and water loss compared to the alone treatment. This was due to the larger starch granule size and fewer grana lamellae around the amyloplasts. Our results provide an effectively strategy that treating potatoes with 600 μL L−1 ethanol combined with modified atmosphere packaging to delay potato greening and explain the underlying mechanism of ethanol inhibition of potato greening.

TinyML-Sensor for Shelf Life Estimation of Fresh Date Fruits.

Fresh dates have a limited shelf life and are susceptible to spoilage, which can lead to economic losses for producers and suppliers. The problem of accurate shelf life estimation for fresh dates is essential for various stakeholders involved in the production, supply, and consumption of dates. Modified atmosphere packaging (MAP) is one of the essential methods that improves the quality and increases the shelf life of fresh dates by reducing the rate of ripening. Therefore, this study aims to apply fast and cost-effective non-destructive techniques based on machine learning (ML) to predict and estimate the shelf life of stored fresh date fruits under different conditions. Predicting and estimating the shelf life of stored date fruits is essential for scheduling them for consumption at the right time in the supply chain to benefit from the nutritional advantages of fresh dates. The study observed the physicochemical attributes of fresh date fruits, including moisture content, total soluble solids, sugar content, tannin content, pH, and firmness, during storage in a vacuum and MAP at 5 and 24 ∘C every 7 days to determine the shelf life using a non-destructive approach. TinyML-compatible regression models were employed to predict the stages of fruit development during the storage period. The decrease in the shelf life of the fruits begins when they transition from the Khalal stage to the Rutab stage, and the shelf life ends when they start to spoil or ripen to the Tamr stage. Low-cost Visible-Near-Infrared (VisNIR) spectral sensors (AS7265x-multi-spectral) were used to capture the internal physicochemical attributes of the fresh fruit. Regression models were employed for shelf life estimation. The findings indicated that vacuum and modified atmosphere packaging with 20% CO2 and N balance efficiently increased the shelf life of the stored fresh fruit to 53 days and 44 days, respectively, when maintained at 5 ∘C. However, the shelf life decreased to 44 and 23 days when the vacuum and modified atmosphere packaging with 20% CO2 and N balance were maintained at room temperature (24 ∘C). Edge Impulse supports the training and deployment of models on low-cost microcontrollers, which can be used to predict real-time estimations of the shelf life of fresh dates using TinyML sensors.

Comparison between vacuum and modified-atmosphere packaging on dynamic analysis of flavor properties and microbial communities in fresh-cut potatoes (Solanum tuberosum L.)

Fresh-cut potatoes are prone to browning and quality deterioration during storage, which leads to a short shelf life. In the present study, we investigated the sensory quality attributes, flavor profiles, and bacterial community composition of fresh-cut potato cubes stored at 4 °C for 18 days in vacuum packaging and 30 % CO2/70 % N2 modified-atmosphere packaging. In addition, a correlation analysis of volatile organic compounds and bacterial taxa was performed. In total, 26 types of volatile organic compounds were identified; aldehydes were considered as the main contributors to the odor, and the off-flavor was mainly described as a mixture of oily, spicy, and beany flavors. The dominant bacteria in all packaged potatoes were fermentative gram-negative bacteria Alcaligenaceae and Sphaerotilus. Notably, compared with vacuum packaging, modified-atmosphere packaging inhibited the generation and development of undesirable flavors and maintained the sensory profile of fresh-cut potatoes in a better manner during storage.

Recent advances in extending the shelf life of fresh wet noodles: Influencing factors and preservation technologies.

Fresh wet noodles (FWNs) are popular among people and have attracted increasing attention because of their characteristics of freshness, chewiness, good taste, and better maintenance of noodle flavor. However, due to the high moisture content and abundance of nutrients in FWN, they are prone to spoilage, which shortens their shelf life and reduces their quality, greatly restricting their large-scale production. Therefore, seeking effective preservation methods to prolong the shelf life is a major breakthrough for the industrialization of FWN. The present review provides a comprehensive overview of the main factors that contribute to the spoilage and degradation of FWN. These factors encompass microorganisms, moisture content, nutritional composition, enzymes, and storage temperature. Moreover, the recent developments in novel shelf-life extension technology applied to FWN, such as chemical preservatives, natural preservatives, physical treatment technologies, and composite preservation technology, are presented and discussed. From the literature reviewed, the application of technologies, such as adding preservatives, modified atmosphere packaging, microwave, cold plasma, ozone, and other technologies, has a certain effect on improving the shelf life of FWN, but the single preservation technology still has some deficiencies. In order to further improve the preservation efficiency, using two or more preservation methods is an important direction for future research on the preservation technology of FWN.

Use of Algerian Type Ras El-Hanout Spices Mixture with Marination to Increase the Sensorial Quality, Shelf Life, and Safety of Whole Rabbit Carcasses under Low-O2 Modified Atmosphere Packaging.

This study aimed to evaluate the effect of combined treatments with Ras El-Hanout spices mixture and marinade solution containing extra virgin olive oil, onion, garlic, and concentrated lemon juice on sensorial quality, shelf life, and safety of whole rabbit carcasses under low-O2 modified atmosphere packaging (MAP). The values of pH, water holding capacity, shear force, thiobarbituric acid reactive substances, total volatile basic nitrogen, color (CIE L*a*b*), sensorial tests, and spoilage microorganisms were determined in rabbit meat at 0, 5, 10, 15, and 20 days during a retail display at 7 ± 1 °C. The results indicated that the marination process using the Ras El-Hanout blend of spices improved the water-holding capacity of meat maintaining optimum pH values. This combined treatment delayed the growth of major spoilage microorganisms, lipid oxidation, protein degradation, and undesirable color changes compared to unmarinated samples from the fifth to the twentieth day of retail exposure. The shelf life of rabbit carcasses under low-O2 MAP could be extended to 20 days of retail display, while rabbit carcasses under aerobic display presented a shorter shelf life of 5 to 10 days. Instrumental and sensorial tests showed that low-O2 MAP enhanced the tenderness of whole rabbit carcasses, with those marinated with Ras El-Hanout being the most positively perceived by the panelists. Marination also inhibited the pathogen Campylobacter jejuni, thus increasing the microbiological safety of the packaged product. The overall results indicated that low-O2 MAP combined with the Ras El-Hanout spice blend and marinade solution may represent a promising strategy for retail establishments to improve the quality, shelf life, and safety of rabbit carcasses.

Effect of sustained-release tea tree essential oil solid preservative on fresh-cut pineapple storage quality in modified atmospheres packaging.

The quality and safety of fresh-cut pineapple deteriorate during handling and storage due to physicochemical and microbial changes, so its preservation has attracted extensive attention. This study prepared sustained-release tea tree essential oil (TTO) solid preservative (SP) with an encapsulation efficiency of 71.45% and applied it on fresh-cut pineapple in modified atmospheres packaging (MAP). Results showed that TTO adsorbed on nano silicon dioxide (SiO2) was embedded in the starch-carboxymethyl cellulose network structure by extrusion. The hydrogen bond and hydrophobic interaction resulted in compact structure and good sustained-release performance of SP. The SP improved sensory quality and reduced nutrient loss and microbial spoilage of fresh-cut pineapple, which extended its shelf-life to four days. In addition, antioxidant capacity was enhanced with increasing antioxidant enzyme activity, antioxidant content, and 2,2-diphenyl-1-picrylhydrazine scavenging capacity and decreasing MDA accumulation. Therefore, sustained-release TTO solid preservative has potential for the preservation of fresh-cut pineapple.

Impactul ambalajelor cu atmosferă modificată asupra concentrației de CO2 și O2 în perioada post-recoltare la două soiuri de cireșe

Sweet cherry fruits are considered to be highly perishable, with a short shelf life and very often cannot reach the final consumer at optimum quality after a longer period of transportation. In this research, four types of modified atmosphere packages were studied related to gas concentration dynamics during the post-harvest period to maintain fruit quality in Kordia and Regina varieties grafted on Gisela 5 rootstock. To determine the effectiveness of modified atmosphere packaging in contrast to normal atmosphere the following experiment was carried out: V1 - normal atmosphere (control); V2 - Trendlife; V3 - Decco; V4 - ESL; V5 - Xtend. Sweet cherries were stored for 42 days at the temperature of -0.5°C. At intervals of 0; 2; 4; 5 and 6 weeks after storage, the CO2 and O2 concentrations were determined using the gas analyzer for CO2 and O2 (Gas Analyzer Avi-Gas, TEXA, Poland). The results were compared to the control variant. Modified atmosphere packages had a positive effect on CO2 and O2 concentrations during storage. The concentration of carbon dioxide increased significantly and the concentration of oxygen decreased, which created favourable conditions for extending the storage life of sweet cherries. The most rational CO2 and O2 concentrations were in the variants where sweet cherries were stored in Decco and Xtend packages.

Effect of vacuum and modified atmosphere packaging on moisture state, quality, and microbial communities of grouper (Epinephelus coioides) fillets during cold storage

The study aimed to assess the impact of different packaging methods on the moisture state, quality, and microbial composition of grouper fillets. The grouper fillets were packaged under the following four conditions: vacuum packaging (VP), 70% CO2/30% N2 (MAP1); 60% CO2/30% N2/10% O2 (MAP2); 40% CO2/30% N2/30% O2 (MAP3). Physicochemical and microbiological parameters were evaluated during 21 days of cold storage. The result demonstrated that MAP was effective in inhibiting microbial growth and accumulation of total volatile basic nitrogen (TVB-N), while also maintaining the water-holding capacity (WHC) of grouper fillets. Additionally, MAP1 effectively inhibited lipid and protein oxidation and protected the secondary structure of myofibrils compared to MAP2 and MAP3, with MAP1 samples having the lowest thiobarbituric acid reactive substances (TBARS) value (0.009–0.04 MDA/kg) and carbonyl content (0.20–0.26 μmol/g) and the highest sulfhydryl content (0.25–0.49 μmol/g) during cold storage. The results of high-throughput sequencing revealed that the presence of oxygen in the packaging system significantly influenced bacterial succession. Over time, Carnobacterium gradually became the dominant genera of fillets stored in MAP, and the presence of oxygen in MAP2 and MAP3 accelerated this transition by 9 days, compared to MAP1. In contrast, Enterobacteriaceae and Carnobacterium were the main dominant genera in VP. Remarkably, Enterobacteriaceae were virtually absent in MAP2 and MAP3 during storage, suggesting that the presence of oxygen exerted a significant inhibitory effect on Enterobacteriaceae. This study provides valuable insights into the application of MAP in the preservation of grouper fillets.

Combined Effect of Cinnamon Bark Oil and Packaging Methods on Quality of Fresh Lamb Meat Patties during Storage at 4 °C.

The present study aimed to investigate the effects of adding cinnamon bark oil (CBO) on the quality of ground lamb meat, considering different packaging conditions, including modified atmospheric packaging (MAP) using Hengxian HX-300H and overwrapped packaging. The CBO was incorporated into lamb meat samples at three different levels: 0% (control), 0.025% and 0.05% (v/w). The samples were then subjected to three packaging methods: MAP1 (80% O2 + 20% CO2), MAP2 (40% O2 + 30% CO2 + 30% N2) and overwrapped packaging and stored at 4 °C for 0, 4, 8, 12 and 16 days. The findings of the present study revealed that the addition of 0.025% and 0.05% CBO under MAP1 condition significantly improved the color of the meat samples after 12 days of storage at 4 °C (p < 0.05). The overwrapped samples exhibited higher levels of thiobarbituric acid reactive substances (TBARS) compared to all other treatments, starting from day 4 of storage (p < 0.05). Furthermore, microbial counts were notably higher in the overwrapped samples than in all other samples after day 8 of storage (p < 0.05). In conclusion, the combination of 0.05% CBO with MAP proved to be an effective strategy for enhancing the color stability and oxidative stability of ground lamb meat. These results suggest that CBO can be utilized as a beneficial protective agent in meat packaging processes.

Impact of humidity, temperature and condensation on O2 and CO2 transmission rate of modified atmosphere packages

This study aimed to determine the effect of different conditions such as packaging materials, relative humidity, temperature and condensation on the transmission rate of gases inside the packages. Bioplastics Natureflex (N) film and petroleum-based material, polypropylene (PP) film were used to cover cylinders with different humidity conditions (0 %, 50 %, and 100 % RH). Then, polypropylene was used to cover trays with modified gases and the effects of different packaging conditions on the transmission rate of polypropylene were determined using a modular sensor system. It was found that polypropylene had lower transmission rate values, albeit no significant difference. The relative humidity of the cylinders also gave no significant effect on the transmission rate values of bioplastics and polypropylene films. Nonetheless, the temperature of the storage contributed a significant (p < 0.05) impact towards transmission rate values of modified atmosphere packages, with lower temperature causing lower transmission rate values to both oxygen and carbon dioxide gases. Meanwhile, different packaging conditions with condensation and different humidity did not influence the transmission rate, as shown in the earlier findings. In conclusion, only certain factors affected the transmission rate of gases in the packages, however, the right variables and a proper storage for explicit foods are vital to ensure their safety and quality.

Modified atmosphere packaging delays postharvest leaf senescence of Chinese flowering cabbage via suppressing chloroplast dismantling and alleviating mitochondrial oxidative damage

Onset of leaf senescence comes with biomolecule degradation and cellular organelle degeneration. Here, we examined the efficacy of modified atmosphere packaging (MAP) on reactive oxygen species (ROS) metabolism and ultrastructural changes of chloroplasts and mitochondria in Chinese flowering cabbage leaves during storage at 20 ± 1 ℃. MAP delayed chloroplast dismantling along with lower chlorophyll reduction and Fv/Fm ratio. Furthermore, the integrity of mitochondrial ultrastructure was maintained by MAP treatment during leaf senescence. MAP treatment also lowered accumulation of ROS and maintained higher levels of key components and enzyme activity of ascorbate–glutathione cycle, as well as expression of BrAPX5, BrGR, BrDHAR1 and BrMDHAR2. Additionally, MAP-treated cabbage leaves showed higher activity of peroxidase, superoxide dismutase, catalase and encoding gene expressions. Collectively, above findings suggest that MAP treatment could suppress chloroplast dismantling and maintain ROS homeostasis to mitigate mitochondrial oxidative damage and sustain mitochondrial structure, thereby postponing senescence of Chinese flowering cabbage.