Nondestructive and Continuous Monitoring of Oxygen Levels in Modified Atmosphere Packaged Ready‐to‐Eat Mixed Salad Products Using Optical Oxygen Sensors,and Its Effects on Sensory and Microbiological Counts during Storage

The objective of this study was to determine the percentage oxygen consumption of fresh, respiring ready‐to‐eat (RTE) mixed leaf salad products (Iceberg salad leaf, Caesar salad leaf, and Italian salad leaf). These were held under different modified atmosphere packaging (MAP) conditions (5% O₂, 5% CO₂, 90% N₂ (MAPC—commercial control), 21% O₂, 5% CO₂, 74% N₂ (MAP 1), 45% O₂, 5% CO₂, 50% N₂ (MAP 2), and 60% O₂, 5% CO₂, 35% N₂ (MAP 3)) and 4 °C for up to 10 d. The quality and shelf‐life stability of all packaged salad products were evaluated using sensory, physiochemical, and microbial assessment. Oxygen levels in all MAP packs were measured on each day of analysis using optical oxygen sensors allowing for nondestructive assessment of packs. Analysis showed that with the exception of control packs, oxygen levels for all MAP treatments decreased by approximately 10% after 7 d of storage. Oxygen levels in control packs were depleted after 7 d of storage. This appears to have had no detrimental effect on either the sensory quality or shelf‐life stability of any of the salad products investigated. Additionally, the presence of higher levels of oxygen in modified atmosphere packs did not significantly improve product quality or shelf‐life stability; however, these additional levels of oxygen were freely available to fresh respiring produce if required. This study shows that the application of optical sensors in MAP packs was successful in nondestructively monitoring oxygen level, or changes in oxygen level, during refrigerated storage of RTE salad products.     

Modelling the respiration rate of minimally processed broccoli (Brassica rapa var. sylvestris) for modified atmosphere package design

In this work, the effect of temperature, oxygen and carbon dioxide on the respiration rate of minimally processed broccoli was studied to develop suitable modified atmosphere packaging. Respiration rate was measured at 3, 5, 7, 10, 15 and 20 °C under different gas compositions of O₂ and CO₂ (1%, 5%, 10%, 15% and 21% of O₂ with the balance N₂, a mixture of 10% and 20% of carbon dioxide with the balance air and a mixture at 3% of O₂ and 15% of CO₂ with the balance N₂). As expected, temperature was the most influential factor on respiration rate, for all atmospheres tested: increasing the temperature from 3 to 20 °C resulted, for air‐stored samples, in a 84% change in oxygen respiration rate, whereas at constant temperature, the respiration rate decreased by 35% with lowering the O₂ concentration from 21% to 1% and by 44% with increasing the CO₂ concentration from 0% to 20%. The Michaelis and Menten competitive model with maximum respiration rate varying against temperature with an Arrhenius equation accurately described the influence of gas composition and temperature on the respiration rate of minimally processed broccoli, and it was used to design a suitable package.     

Effect of controlled atmospheres with varying O2/CO2 levels on the postharvest senescence and quality of broccoli (Brassica oleracea L. var. italica) florets

Controlled atmosphere (CA) has been widely used to help extend the shelf life and maintain the quality of horticultural products. In the present study, broccoli (Brassica oleracea L. cv. Youxiu) florets were stored under CA with high levels of O₂/CO₂ at 15 °C, including 100 % O₂, 80 % O₂ + 20 % CO₂, 60 % O₂ + 40 % CO₂, 40 % O₂ + 60 % CO₂, and air (control), to determine the effects of CA on storage period and on some physiological properties during storage. The results showed that compared with the control, the treatments combining O₂ and CO₂ effectively extended the storage period and inhibited respiration rate, ethylene production, and reductions in weight loss, chlorophyll, and ascorbic acid levels. Moreover, the CA treatments inhibited the increases in both superoxide radicals (O ₂ ^?· ) production rate and hydrogen peroxide (H₂O₂) level and reduced malondialdehyde accumulation, which could be beneficial in delay of senescence by alleviation of oxidative damage. In addition, broccoli florets exposed to CA conditions maintained lower activities of superoxide dismutase and peroxidase that are responsible for scavenging of O ₂ ^?· and H₂O₂ and alleviating lipid peroxidation. Among the treatments, the maximum efficacy was observed with a CA of 40 % O₂ + 60 % CO₂, which prolonged the storage period of broccoli heads to 17 days (d) compared with 4 d under air treatment. Conversely, 100 % O₂ treatment accelerated senescence and deterioration in the quality of broccoli, resulting in a shorter storage period. These results suggest that the establishment of an appropriate CA condition with high levels of O₂/CO₂ may be an ideal strategy for maintaining the quality of broccoli florets during storage.     

Sensory and microbiological quality of shiitake mushrooms in modified‐atmosphere packages

The aim of the present work was to study the influence of modified‐atmosphere packaging on the microbiological and sensory quality of shiitake mushrooms (Lentinula edodes). Mushrooms were packaged under atmospheric air (passive modified atmosphere) and an initial gas mixture of 5% O₂ and 2.5% CO₂ (active modified atmosphere), in bags of two different films: low‐density polyethylene (PE) and polypropylene (PP). As control, mushrooms were packaged in macroperforated PP films. Bags were stored at 5 °C for 20 days. Package atmosphere composition, mushroom respiration rate, weight loss, microbiological counts and sensory quality were determined during storage. Risk assays were also performed. Under the studied conditions, shiitake mushroom deterioration was not due to microorganism growth, and therefore the shelf‐life of this product might be defined by changes in its sensory characteristics. Sensory analysis showed that mushrooms stored under modified atmosphere (active and passive) had a higher deterioration rate than those stored in PP macroperforated films, and lower sensory quality values during the entire storage time. These results suggest that mushroom deterioration was probably due to shiitake mushrooms' sensitivity to high CO₂ concentrations. Copyright © 2007 Society of Chemical Industry     

Shelf‐life extension of refrigerated seabass slices under modified atmosphere packaging

The effect of CO₂‐enriched atmosphere in combination with either oxygen or nitrogen on the keeping quality of seabass slices stored at 4 °C was investigated. The inhibitory effect on bacterial growth increased proportionally to the CO₂ concentration in the packaging, maximum inhibition being achieved with 100% CO₂ (P < 0.05). Seabass slices stored in CO₂‐enriched atmosphere had lower total volatile base, trimethylamine, ammonia and formaldehyde contents than those stored in air (P < 0.05). However, increases in lightness and exudate loss were observed for samples packaged in high‐CO₂ atmosphere, suggesting the denaturation of both muscle and pigment proteins by carbonic acid formed. Thiobarbituric acid‐reactive substances (TBARS) increased as the CO₂ concentration increased (P < 0.05). However, odour, flavour and overall acceptability of CO₂‐enriched packaged samples, particularly with 80 and 100% CO₂, were acceptable throughout storage for 21 days. Chemical and microbial changes in all samples were generally in agreement with sensory panel evaluations. The shelf‐life of seabass slices packaged in 80–100% CO₂ atmosphere could be extended to more than 20 days at 4 °C, compared with 9 days for those packaged in air. © 2002 Society of Chemical Industry     

Antioxidant properties and shelf‐life extension of fresh‐cut tomatoes stored at different temperatures

BACKGROUND: The feasibility of using modified atmosphere packaging (5 kPa O₂ + 5 kPa CO₂) to maintain the antioxidant properties of fresh‐cut tomatoes during shelf‐life was assessed through storage at different temperatures (5, 10, 15 and 20 °C). Health‐related compounds, antioxidant capacity, microbiological counts, physicochemical parameters and in‐package atmosphere of tomato slices were determined. RESULTS: Initial lycopene, vitamin C and phenolic contents and physicochemical parameters of tomato slices were well maintained for 14 days at 5 °C. Lycopene and total phenolic contents were enhanced over time in tomato slices stored at 15 and 20 °C. However, this increase in antioxidant compounds of fresh‐cut tomatoes during storage may be associated with excessive amounts of CO₂ (R² = 0.5679–0.7328) in the packages due to microbial growth. Although keeping tomato slices at temperatures above 10 °C increased their antioxidant content, the shelf‐life of the product was reduced by up 4 days. CONCLUSIONS: A storage temperature of 5 °C is appropriate for maintaining the microbiological shelf‐life of fresh‐cut tomatoes for up to 14 days and also allows the antioxidant properties of tomato slices to be retained over this period, thus reducing wounding stress and deteriorative changes. Copyright © 2008 Society of Chemical Industry     

Different postharvest strategies to preserve broccoli quality during storage and shelf life: Controlled atmosphere and 1-MCP

Broccoli (Brassica oleracea var. italica) is a vegetable that requires the application of postharvest techniques to extend its marketability. Controlled atmosphere and 1-MCP treatments are most used to extend the shelf life of broccoli and reduce post-harvest deterioration. The aim of this study was to evaluate the visual, physicochemical and functional changes of broccoli head samples stored at 1–2 °C and 85–90% relative humidity (RH) in air (Control samples), under controlled atmospheres (10% O₂ and 5% CO₂) (CA samples) and treated with 1-MCP (0.6 μL/L). After storage all samples were maintained at 20 °C for 2 and 4 days, in order to assess their shelf life. The most suitable postharvest treatment to extend broccoli quality during storage and shelf life, in terms of maintaining the visual quality and reducing loss of health-promoting compounds, was achieved by storage under controlled atmosphere conditions. The use of 1-MCP reduced the loss of green colour and chlorophyll pigments, but only during cold storage not during shelf life at 20 °C.     

Optimal Controlled Atmosphere Conditions for Storage of Broccoli Florets

Minimally processing broccoli heads into florets increased the rate of respiration throughout storage at 4°C in air, in response to wounding stress. Ethylene production was also stimulated after 10 days. At-mospheres for optimal preservation of the florets were evaluated using continuous streams of the following defined atmospheres (%CO₂/%O₂): O/20 (air control), 6/1, 6/2, 6/3, and 3/2, 6/2, 9/2. The atmosphere consisting of 6% CO₂+ 2% O₂ resulted in extended storage of broc-coli florets from 5 wk in air to 7 wk. This was demonstrated by delayed yellowing, prolonged chlorophyll retention, reduced development of mold and offensive odors (by sensory observation), and better water retention. These beneficial effects were especially noticeable when the florets were returned from CA at 4°C to air at 20°C.     

SHORT‐TERM CONTROLLED ATMOSPHERE STORAGE FOR STORAGE‐LIFE EXTENSION OF WHITE‐FLESHED PEACHES AND NECTARINES1

Abstract Response of white‐fleshed peaches (‘Sugar Lady’, ‘Snow Giant’, ‘White Lady’and ‘Snow King’) and nectarines (‘Arctic Queen’and ‘Arctic Rose’) to controlled‐atmosphere (CA) storage is cultivar dependent. Samples of fruit of these six cultivars were collected just prior to commercial harvest and held in either regular‐atmosphere (RA) storage at 1C or controlled‐atmosphere (CA) storage at 2% O₂ and 6, 12 or 18% CO₂, all at 1C. Four of the six cultivars (‘Snow Giant’, ‘White Lady’, ‘Snow King’and ‘Arctic Queen’) displayed excessive internal browning and poor flesh color after only 30 days of storage and should not be considered for long storage (+30 days). While ‘Sugar Lady’and ‘Arctic Rose’performed better and are possible candidates for CA storage, they should not be stored more than 45 days after harvest. The value of CA storage to extend the marketing of white‐fleshed peaches and nectarines is questionable at best. If CA storage is to be used for storage‐life extension of white‐fleshed peaches and nectarines, O₂ level should be maintained at 2% or less and CO₂ level maintained at 12% or higher.     

EFFECT OF ATMOSPHERE ON BROCCOLI SENSORY ATTRIBUTES IN COMMERCIAL MAP AND MICROPERFORATED PACKAGES1

Broccoli was packaged using 2 microperforated (cross-micro, SM60®) and 3 modified atmosphere packages (MAP) (polyethylene MAP, broccoli MAP, lettuce MAP). Packaged broccoli was stored 9 days at 2C and an additional 1, 3, 4 and 6 days at 13C, for a total storage 10, 12, 13 and 15 days, respectively. Concentrations of CO₂ and O₂ were determined after 12 days. Sensory analyses were conducted after 10, 12, 13, and 15 days. Broccoli quality was evaluated for ten sensory attributes by eight trained judges. Analysis of variance and principal component analysis were used to determine the effect of packaging and storage time. Broccoli packaged in lettuce MAP was most anaerobic (3.9% CO₂, 1.2% O₂) and developed sauerkraut-like odors/flavors after 10 days of storage. The microperforated wraps did not alter the gas composition of the packages (16.3% O₂, 0.2% CO₂) and broccoli became yellow and limp after 15 days. In contrast, broccoli packaged in the polyethylene and broccoli MAP packages modified the CO₂ and O₂ concentrations and maintained the broccoli quality for the duration of the experiment (15 days).     

Effect of initial oxygen concentration and film oxygen transmission rate on the quality of fresh‐cut romaine lettuce

Modified atmosphere packaging (MAP) is widely used to maintain the quality of fresh‐cut produce by matching the oxygen transmission rate (OTR) of the packaging film to the respiration rate of the packaged product. The effect of the interaction between film OTR and the initial headspace O₂ on quality of fresh‐cut vegetables has not previously been reported. Romaine lettuce leaves were sliced, washed, dried and packaged with film OTRs of 8.0 and 16.6 pmol s^?1 m^?2 Pa^?1, and with initial headspace O₂ of 0, 1, 2.5, 10 and 21 kPa. Packages were hermetically sealed and stored at 5 °C for up to 14 days. For samples packaged in 16.6 OTR film, increasing the initial headspace O₂ concentration delayed O₂ depletion within the packages, hastened the onset and increased the intensity of discoloration, and inhibited the development of CO₂ injury, acetaldehyde and ethanol accumulation, off‐odors and electrolyte leakage. With 8.0 OTR‐packaged lettuce pieces, ≤1 kPa initial headspace O₂ treatments induced an essentially anaerobic environment within the packages and increased acetaldehyde and ethanol accumulation and off‐odor development. Increasing the initial O₂ concentration above 1 kPa in 8.0 OTR packages transiently increased O₂ concentrations and reduced fermentative volatile production, off‐odors, electrolyte leakage and CO₂ injury. Regardless of initial headspace O₂ concentration, all 16.6 OTR‐packaged samples had severe discoloration after 14 days of storage. Quality was better maintained in 8.0 OTR‐packaged lettuce pieces as the initial headspace O₂ concentration was increased. A 21 kPa initial O₂ treatment of 8.0 OTR‐packaged lettuce maintained good quality throughout storage and had the best overall quality score. Copyright © 2005 Society of Chemical Industry     

Optimization of processing of fresh‐cut pear

BACKGROUND: Successful processing of pears to render fresh‐cut fruits requires a thorough knowledge of their sensitivity to browning reactions, their respiratory metabolism, and their behaviour under modified atmosphere packaging. RESULTS: First, three different varieties of pear (Williams, Conference, Passacrassana) that had reached their commercial ripening stage were evaluated for suitability for minimal processing. Two antioxidant treatments were tested (treatment 1: 2% ascorbic acid + 1% citric acid + 1% CaCl₂; treatment 2: 2% ascorbic acid + 0.01% 4‐hexylresorcinol + 1% CaCl₂) to decide which one was the most effective against enzymatic browning. Finally, a modified atmosphere packaging was designed after two previous tests: measurement of respiratory activity of the peeled and cut pear at three temperatures (4, 15 and 25 °C); and evaluation of fruit tolerance to three different atmospheric compositions (21% O₂ + 10% CO₂; 2% O₂ + 0% CO₂; 2% O₂ + 10% CO₂). CONCLUSIONS: Conference pear was found to be the most suitable variety. Among the antioxidant treatments the one consisting of ascorbic acid, 4‐hexylresorcinol and CaCl₂ was proven to be the most effective against browning. The samples were packaged in a modified atmosphere with a composition of 10% O₂ + 10% CO₂ + 80% N₂. Copyright © 2008 Society of Chemical Industry     

Physiological responses and quality attributes of ‘Kyoho’ grapes to controlled atmosphere storage

This research studied the physiological responses and quality attributes of Kyoho grapes (Vitis vinifera X V. labrusca) to controlled atmosphere storage. The grapes were stored for up to 60 days in 95% relative humidity with four different conditions, 4% O₂+9% CO₂, 4% O₂+30% CO₂, 80% O_2, and air, as control. The examined physiological responses and quality attributes included polyphenol oxidase (PPO) activity, ethanol concentration, fruit detachment force (FDF), firmness, color, soluble solid content (SSC), titratable acidity (TA), ascorbic acid concentration (Vc), and sensory quality. PPO activity, FDF drop and decay incidence when stored in 4% O₂+30% CO₂ were more effectively controlled, but unacceptable alcoholic flavor and browning were detected after 45 days, compared with those stored in 4% O₂+9% CO₂ or 80% O₂. The fruits kept in 4% O₂+9% CO₂ or 80% O₂ had good quality during 60 days of storage. The results suggested that high O₂ atmosphere exhibited a potential for maintaining the quality of ‘Kyoho’ grapes during long-term storage.     

SENSORY, NUTRIENT AND CHLOROPHYLL CHANGES IN BROCCOLI FLORETS DURING CONTROLLED ATMOSPHERE STORAGE

Sensory (color, turgor, decay) and nutritional (vitamin C, β-carotene) quality of broccoli florets were evaluated during storage at 4C in air or under a controlled atmosphere containing 2% O₂+ 6% CO₂ (CA). Shelf-life, green color and chlorophyll retention were greater under CA than in air, although loss of stem turgor was accelerated. All samples stored in air had decayed sufficiently by the fourth week to be unfit for consumption, while samples stored under CA showed a few spots of decay after five weeks. However, CA was associated with browning at the cut surface of the stem. Retention of vitamin C was slightly greater in CA than in air, while β-carotene content increased at the end of CA storage. Returning the samples to ambient conditions for 24 h after storage under either conditions resulted in chlorophyll and vitamin C losses, whereas β-carotene content remained stable.     

Microbiological,physical and chemical characteristics of freshwater prawns (Macrobrachium rosenbergii) in modified‐atmosphere packaging

This study evaluated the influence of packaging atmosphere (air versus 50% N₂/50% CO₂) on microbiological (mesophiles, psychrotrophs), physical (gas measurement) and chemical (pH, total volatile basic nitrogen [TVB‐N], NH₃, H₂S and biogenic amines) parameters in freshwater prawns during storage at 0 ± 1 °C for 240 h. To select the most appropriate packaging, 21 batches of each treatment were analysed. Both the packaging permeability and the combination of gases affected the shelf life, but the modified‐atmosphere packaging (MAP) was more efficient than air packaging, increasing the shelf life by 40 h. The parameters of pH and TVB‐N showed no statistical difference between the two atmosphere conditions all along the storage period. The biogenic amine agmatine showed potential for use as a quality indicator due to the increased concentration during storage. In further studies, this amine can be applied as an indicator for public health issue.     

The response to lighting of minimally processed chard: Influence on its shelf life

BACKGROUND: The effect of lighting on minimally processed chard during storage was studied. To compare the influence of pigmentation on the behaviour of the vegetable when exposed to light, the white and green parts were processed separately. Four films with different permeabilities were tested. RESULTS: Lighting caused an increase in stomatal aperture and respiratory rate. White chard stored under lighting achieved atmospheres with higher CO₂ and lower O₂ content than samples packed in the same film kept in the dark. The green part stored under lighting saw respiratory activity compensated by photosynthesis and the composition of the atmosphere remained similar to atmospheric conditions inside all films. After day 15 of storage, with pigment breakdown terminating photosynthesis, respiratory activity gave atmospheres of up to 10% O₂ and 9% CO₂ in P‐Plus 120 film. CONCLUSION: Exposure to light lowered quality in both the green and white parts of chard, significantly reducing its shelf life. P‐Plus 120 film best preserved the sensory qualities and allowed a longer shelf life to be achieved for both white and green chard in all storage conditions. Colour was particularly affected in lit conditions in the white section samples. For the green samples, it was texture that deteriorated the most. Copyright © 2008 Society of Chemical Industry     

Combined Application of Antibrowning,Heat Treatment and Modified‐Atmosphere Packaging to Extend the Shelf Life of Fresh‐Cut Lotus Root

This work aimed to determine the effects of different concentrations of antibrowning treatments (that is, distilled water [DW], 1% ascorbic acid [AA], 0.5% chamomile [CM], and 1% AA + 0.5% CM) and heat‐treatment (55 °C for 45 s) combined with packaging under 4 different modified‐atmosphere gas compositions (that is, air, vacuum, 100% CO₂, 50% CO₂/50% N₂) on the quality and microbiological characteristics of fresh‐cut lotus root. The quality characteristics (that is, color, weight loss, texture, pH, polyphenoloxidase activity, and total phenolic content) of the AA + CM‐dipped sample in 100% CO₂ packaging were maintained significantly better than those of the other samples (P < 0.05). The microbiological counts observed in the DW‐dipped sample during storage were higher than those of the AA, CM, and AA + CM samples, and heat‐treatment retarded the microbiological deterioration of fresh‐cut lotus root. Therefore, the results revealed that dipping in an antibrowning treatment (AA + CM), and 100% CO₂ MAP with heat treatment effectively extend the shelf life of fresh‐cut lotus root to 21 d at 5 °C.     

Controlled‐atmosphere storage of tomato fruit: low oxygen or elevated carbon dioxide levels alter galactosidase activity and inhibit exogenous ethylene action

The effects of 3% O₂ and 20% CO₂, both alone and together with 100 µg g⁻¹ C₂H₄, on ethylene production, chlorophyll degradation, carotenoid biosynthesis and α‐ and β‐galactosidase activity in breaker tomato (Lycopersicon esculentum Mill) fruit were investigated. The low O₂ and high CO₂ atmospheres prevented the rise in ethylene production, total carotenoid and lycopene biosynthesis and α‐ and β‐galactosidase activity and slowed down chlorophyll degradation and loss of firmness (P < 0.05). These suppressive effects were not reversed, or only in part – in the case of chlorophyll breakdown – by addition of 100 µg g⁻¹ C₂H₄ to said controlled atmospheres. After transfer from the various atmospheres to air, flesh firmness decreased and ethylene production, total carotenoids, lycopene and β‐galactosidase II activity increased but these parameters were, in all cases, still significantly different from those of fruit held in air. Keeping tomatoes in controlled atmospheres, even in the presence of ethylene, had marked residual effects. Results suggest an antagonism between elevated CO₂/low O₂ and exogenous ethylene which could determine most of the ripening parameter behaviour under controlled‐atmosphere storage, though a direct regulatory mechanism by O₂ and/or CO₂ should not be discarded. © 1999 Society of Chemical Industry     

Effects of type of packaging material on shelf-life of fresh broccoli by means of changes in weight,colour and texture

Five polymeric films were studied to determine their ability to retain the colour, weight and texture of broccoli (Brassica oleracea L. var. Italica Monterey). The materials were oriented polypropylene (OPP), polyvinyl chloride (PVC) and two different low-density polyethylenes (LDPE), one of which contained a sachet reported to absorb ethylene. The broccoli was packaged and stored at 4 and 10 °C for 4 weeks. The weight, colour, chlorophyll content and texture were monitored during storage as well as O₂ and CO₂ concentrations inside the packages. Packaging prolonged the broccoli shelf-life by up to 14 days. The shelf-life varied depending on the packaging material and quality parameter considered. The atmosphere was modified inside the packages; however, no package provided the recommended atmosphere (O₂ 1–2% and CO₂ 5–10%) for broccoli. Packaging in OPP resulted in the highest CO₂ concentration, 6%, while the lowest O₂ concentration, 9%, was created in the LDPE package without a sachet for ethylene absorption. Storage in LDPE without ethylene absorber resulted in the overall longest shelf-life. Broccoli stored in PVC deteriorated faster than broccoli packaged in the other materials. The influence of packaging material was greater at the higher temperature.     

Control of internal browning and quality improvement of ‘Fuji’ apples by stepwise increase of CO2 level during controlled atmosphere storage

To control internal browning injury and to reduce quality loss in ‘Fuji’ apples during storage, a stepwise controlled atmosphere (CA) method was applied in this study. Both non‐bagged and bagged apples during maturation were stored at 0 °C under 1% O₂ + 1% CO₂, 1% O₂ + 3% CO₂ or air for 10 months, and 1% O₂ + 1% CO₂ for 2 months followed by 1% O₂ + 3% CO₂ for 8 months (stepwise CA). The concentrations of internal ethylene and carbon dioxide in apples kept for 24 h at 20 °C after storage under CA conditions were maintained at low level, but there was no effect of stepwise CO₂ increase on internal gas concentrations. The non‐bagged and bagged apples stored under stepwise CA were not significantly different from those stored under 1% O₂ + 3% CO₂ continuously for 10 months in term of flesh firmness, titratable acidity and yellowing index. However, the apples stored under stepwise CA were firmer, more acid and greener than those stored under 1% O₂ + 1% CO₂ continuously for 10 months. Internal browning injury occurred in apples stored under 1% O₂ + 3% CO₂ continuously for 10 months, but it was suppressed completely by stepwise CA storage. The stepwise CA, increasing of CO₂ level after holding at 1% CO₂ for the first 2 months of storage, was effective in maintaining the quality and controlling the internal browning injury in non‐bagged and bagged ‘Fuji’ apples. Copyright © 2005 Society of Chemical Industry