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The changes of metabolites in pork patties with different antioxidants added (control without antioxidants, 200 mg kg(-1) butylated hydroxytoluene (BHT) and 250 mg kg(-1) guarana seed extracts (GSEs)) under modified atmosphere (80% O-2 and 20% CO2) for 18 days of refrigerated storage were evaluated. Untargeted metabolomic approach based on UHPLC-ESI-QTOF-MS analysis was applied. GSE phytochemical profile revealed a wide variety of compounds (caffeine, glycerol 1-propanoate, amino acids, alkaloids and glycerophospholipids), together with antioxidants (tyrosols, procyanidins and flavonoids). Important differences in BHT and GSE patties metabolomic profiles were found during storage. Most of the differences could be attributed to glycerophospholipids and fatty acyls, along with specific compounds derived from lipid oxidation (i.e. 2-hexenal, 4-hydroxy-2-hexenal and 2,4-heptadienal) and protein degradation (spermine). Therefore, the approach used highlighted a modulation of lipid oxidative processes, together with strict correlation between metabolic profiles and factors associated with meat quality, highlighting GSE effect on active compounds delaying oxidative phenomena.

An integrated control strategy on preventing pericarp browning (BI) and decay incidence (DI) of longan fruit was investigated to replace sulphur dioxide (SO₂) fumigation. Fruit was treated with 5% ascorbic acid (AA), citric acid (CA), oxalic acid (OA), thymol (TH) and 2% chitosan (CH) for 5 min; sealed under modified atmosphere packaging (MAP) using high permeable film; and stored at 5 °C. Fruit treated with distilled water and sealed under MAP condition (MAPC) and air condition (AIRC) was used as controls. Combined effects of chemical treatments and MAP maintained quality of longan for 56 and 49 days in CH and TH, respectively, as compared to 28 days in MAPC and 21 days in AIRC. AA, CA and OA prevented BI, restrained enzyme activities and maintained high phenols. AA, CA and OA were most potent BI inhibitors; however, DI was the limitation of these treatments, while CH and TH effectively inhibited DI.

Shrimp residues were dried (65 °C), grounded, and posteriorly used as an ingredient to the production of ‘spiced shrimp flour’ and ‘shrimp flavoured biscuits’. Both products were packed in modified atmosphere (100% N₂) and stored for 180 days (25 °C) for shelf life evaluation. The centesimal composition, physicochemical, microbiological and sensory analyses were carried out in triplicate. The microbiological analysis (residue and shrimp flour) was within the limits of the legislation, confirming the hygienic–sanitary care during processing. The protein content was the most outstanding (40.13% for the spiced shrimp flour and 20.52% for the shrimp flavoured biscuits). The microbiological evaluation for the ‘spiced shrimp flour’ and ‘shrimp flavoured biscuits’ was below the legal limit, and both products were accepted by sensory analysis. The shelf life evaluation demonstrated stability for 6 months. Thus, we concluded that the Litopenaeus vannamei shrimp residue is a promising ingredient in the food industry.

Summary Solid-phase microextraction (SPME) GC-MS was used to investigate the volatile organic compound (VOC) profile of fresh-cut ‘Big Top’ nectarine samples, stored in unsealed bags (AIR) or packed in active modified atmosphere (MAP) after 8 days of cold storage. Nectarine slices were also subjected to sensory and quality analysis after harvest and at the end of the storage. MAP preserved the overall quality, the appearance and the olfactory properties of nectarine slices during storage, while AIR samples showed symptoms of dehydration and browning. Sixty VOCs were identified in total in the headspace of the fresh nectarines and cold-stored fruit slices samples. Principal component analysis performed on VOCs allowed to differentiate fresh nectarines from cold-stored samples, with lactones and terpenes mainly related to fresh samples, and ester compounds positively correlated to AIR or MAP samples. Partial least square regression models allowed to identify a pool of VOC predictors of olfactory sensory descriptors.

Sulphur dioxide has been used to control pericarp browning in longan fruit. However, due to health and regulatory concerns, alternative treatments should be tested. The objective of this study was to find the tolerance levels of longan fruit to low O2 (2%, 5%, 10% and 15%) and elevated CO2 (5%, 10%, 15% and 20%) at 2 °C. According to the tolerance study, controlled atmospheres (CA) of 5% O2 + 5% CO2, 5% O2 + 10% CO2 and 5% O2 + 15% CO2 were compared with normal air (control) at 2 °C. Pericarp browning and decay incidence of longan were significantly (P ≤ 0.05) higher in control than all the CA treatments. CA storage reduced polyphenol oxidase (PPO) activity, maintained L* value and slowed down a decrease in total phenolic contents (TPC). Pericarp browning was highly correlated with PPO, L* and TPC.

In this study, tuna burgers were subjected to a bio-preservation treatment combined with modified atmosphere packaging (MAP) in order to prolong the shelf life. After L. reuteri production of reuterin, the antimicrobial compound was microencapsulated and then added to tuna burger formulation. Reuterin content was analysed before and after the spray drying treatment, thus assessing its final concentration. Then, the effects of spray-dried reuterin on tuna burgers quality were investigated with success on samples packaged under both ordinary and MAP conditions. The efficacy of bio-control was evident in all the samples. For burgers stored in air, a shelf life of about 7.63 days was recorded for the active samples with respect to the 5.78 days of the reuterin-free samples. Under MAP, a similar reuterin effectiveness was recorded but a general shelf life improvement was reached, accounting for about 13 days in the active samples and 12 days in the reuterin-free samples.

Summary Fresh coriander samples were washed in an aqueous chlorine dioxide solution and stored in modified atmosphere packaging (MAP) with air (T0), 4%O2 + 3%CO2 + 93%N2 (T1); 10%O2 + 3%CO2 + 87%N2 (T2); 15%O2 + 3%CO2 + 82%N2 (T3); 20%O2 + 3%CO2 + 77%N2 (T4) at 4 °C for 14 days. After 14 days, the ascorbic acid contents in samples were 24.8 (T3), 22.4 (T4), 19.6 (T0), 18.2 (T2) and 8.8 (T1) mg/100 g; the total phenol contents were 59.9 (T3), 53.8 (T0), 50.1 (T4), 44.8 (T2) and 39.3 (T1) mg gallic acid/100 g; and the total chlorophyll contents were 1.60 (T3), 1.52 (T4), 1.05 (T2), 0.91 (T0) and 0.63 (T1) mg g−1 respectively. T3 treatment resulted in the best colour maintenance, the least bacterial growth, and the highest activities of superoxide dismutase and catalase throughout the storage period as compared to others. The data revealed that the T3 MAP condition in combination of aqueous chlorine dioxide washing significantly (P

Summary This study was aimed at understanding the role of film permeability in modified atmosphere packaging (MAP) of longan fruits. Fruits were stored at 2 °C in polyethylene (PE) bags of different gas transmission rates (PE-3000, PE-6000 and PE-10000), compared to commercial polypropylene (PP; PP-1000). PE-3000 and PE-6000 maintained the longest shelf life of 46 days. Fruits in the PE-10000 had the shelf life of 39 days as limited by pericarp browning and decay. The shortest shelf life of 27 days was observed in the PP-1000 due to fermentative metabolism under anaerobic condition. These retail ready packages can potentially be used as an alternative to or with reduction in SO2 fumigation for longan.

Summary Aqueous ozone was first used to take the place of chlorine as fresh-cut apples sanitiser. Aqueous ozone (1.4 mg L−1) treatments were evaluated for their effectiveness on microbial growth, quality attributes and shelf life of fresh-cut apples. The results indicated that aqueous ozone treatments for 5 and 10 min achieved accepted microbial quality and, respectively, reduced total bacteria counts by 1.83 and 2.13 log10CFU g−1 compared with the control samples on the 12th day. The ethylene production, polyphenol oxidase and peroxidase activities, and total phenol and malondialdehyde contents were reduced by aqueous ozone treatments. In addition, this sanitiser also delayed the quality deterioration of fresh-cut apples and enhanced their antioxidant capacity. Therefore, it was recommended to sanitise fresh-cut apples with aqueous ozone (1.4 mg L−1) for 5 min, which applied to industrial production requirement for both efficiency and costs and could extend the shelf life up to 10 days.

Summary A mathematical model was developed from experimental measurements to describe the evolution of the O2, CO2 and ethylene in a modified atmosphere packaging system for Cavendish bananas. The respiration and ethylene production in the fruits were experimentally obtained from a closed system method and then represented by Michaelis–Menten equations of enzyme kinetics. The gas transfer through the packaging was described by a Fick's diffusion equation, and the temperature dependence was represented based on the Arrhenius law. The model was validated by packaging the fruit in perforated bags of polypropylene and low density polyethylene at 12 °C for a period of 8 days. With the developed model it was possible to satisfactorily describe the experimental evolution of the gas content in the headspace of the packages, obtaining coefficients of determination (R2) of 0.93 for the O2 levels, 0.90–0.91 for the CO2 levels, and 0.89–0.93 for the ethylene levels.

Summary A novel container system with a time-controlled perforation device was designed to create a modified atmosphere (MA) beneficial for preserving 1.5 kg of enoki mushrooms at 10 °C. Periodic cycles of meeting and eclipse of the block-arc-shaped perforations on the rotor and the fixed container cover in the device provided the repeated time-controlled opening/closing of the perforation to control the gas transfer. A mathematical model describing the container atmospheric change was used to determine an optimal design, which is specified with circular opening ratios of 7% for the rotor and 10% for the fixed cover for a 4-h cycle. The design could create an MA of 1.8% O2 and 19.4% CO2 to preserve the quality in terms of weight loss, mushroom development, colour change, texture and overall appearance. The cycled time control of the perforation was found as an effective means to have MA condition keeping enoki mushrooms fresh.

The objective of this study was to evaluate the influence of two different vacuum ageing times (7 and 14days) and the impact of the modified atmosphere packaging (MAP) configuration (gas/product ratios: 0.5 and 1 and gas composition: 70% O-2 + 30% CO2 and 40% O-2 + 30% CO2 + 30% N-2) on the quality of fresh beef during subsequent storage at 4 degrees C. For this purpose, three separate experiments were performed. For each experiment, two different muscles (Longissimus dorsi and Biceps femoris) were sampled from four double-muscled Belgian Blue beef carcasses. Next to colour, also the evolution in microbial load, pH, O-2 and CO2 in the headspace and lipid oxidation at the meat surface were evaluated. A vacuum ageing for 14days compared with 7days resulted in a higher initial microbial load on the day of MAP packaging, which resulted finally in a significantly shorter shelf life. This ageing effect was less pronounced on the colour stability and lipid oxidation of the meat samples. No significant influence of the packaging configuration on any of the analysed parameters (colour, microbial load, pH and lipid oxidation at the meat surface) was observed.

Summary Fresh-cut ‘Big Top’ nectarines were dipped in 2% (w/v) ascorbic acid–1% (w/v) calcium lactate and stored at 4 °C for up to 12 days in 10 kPa O2- and 10 kPa CO2-modified atmosphere packaging (MAP). The used microperforated plastic film allowed O2 and CO2 concentrations to reach steady values from the fifth day in storage onwards. Samples stored in MAP after chemical dipping showed the highest visual quality score, slight browning symptoms, increment in firmness and very low ethanol and acetaldehyde content. The chemical dipping also increased antioxidant capacity, probably due to the effect of ascorbic acid. The results suggested that the control of yeasts was mainly exerted by MAP, whereas only a slight effect was achieved by the chemical dipping. Therefore, MAP plus ascorbic acid/calcium lactate dipping was the best combination to preserve phytochemical content, antioxidant capacity and microbiological safety of fresh-cut nectarines during storage.

Summary The aim of this work was to evaluate the effect of various atmosphere compositions (20% CO2/80% N2 for modified atmosphere packaging (MAP) 1, 50% CO2/50% N2 for MAP 2, 70% CO2/30% N2 for MAP 3 and vacuum packaging) on the microbial (mesophiles, psychrophiles, Pseudomonas spp., Brochothrix thermosphacta and Enterobacteriaceae), physical, chemical [trimethylamine (TMA) and total volatile basic nitrogen (TVBN)] and sensorial characteristics of broadtail squid (Illex coindetii) stored for 10 days at 2 ± 1 °C. All microbial populations were severely restrained by MAP 3 with the exception of Enterobacteriaceae, which seemed to take advantage of the lack of competitive microflora and had enhanced microbial counts on MAP samples (P

Summary The aim of this work was to determine the enzymatic activities of catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) together with the total phenolic and carotenoid contents and antioxidant capacity of two cultivars of cactus stems under modified atmosphere packaging containing a passive atmosphere, an active (with N2) atmosphere and control (unsealed polyurethane trays) all stored at 4 ± 1 °C. Results indicated that Atlixco cultivar cactus stems had a shelf life that was twice as long (20 days) than that of Milpa Alta cultivar under N2 MAP. The total enzyme activities of SOD, APX and CAT as well as the carotenoid content were higher in Atlixco than in Milpa Alta. The antioxidant enzymatic and non-enzymatic systems as well as the antioxidant capacity and the phenolic content retention determined in Atlixco cactus stems under N2 MAP appear to explain the longer postharvest life of this cultivar.

Summary This study compared the behaviour of hot paprika (Capsicum annuum L.) samples from the district of La Vera and the region of Murcia packaged in five different conditions during storage. The following five different packaging conditions were used in this study: modified atmosphere packaging with three different conditions (100% N2; 50% N2 and 50% CO2; and 100% CO2), vacuum packaging and traditional packaging (product packaging system without modifying the atmosphere). After the samples were packaged, they were stored for 8 months at room temperature (normal storage conditions). The following parameters were used to indicate the quality of the samples: Aw, ASTA colour, CIEL*a*b* colour parameters, and the composition of red and yellow compounds. The results indicate that the modified atmosphere packaging and vacuum packaging exerted a protective effect on the paprika quality characteristics regardless of the paprika origin. However, no clear differences were detected between the effect of vacuum packaging and the different modified atmosphere packaging conditions.

Summary The impact of heat treatment using hot air (HT 45 °C and 55 °C for 1 h) and two active modified atmosphere packaging (MAP) conditions of high oxygen atmosphere (HOA: 80 kPa O2, 20 kPa N2) and high CO2 atmosphere (HCA: 20 kPa CO2, 80 kPa N2), individually or combined, on the antioxidant capacity, polyphenols, vitamin C content, total anthocyanins, polyphenoloxydase (PPO) activity and shelf life of fresh-cut (FC) pomegranate arils stored for 14 days at 4 °C was studied. The results indicate that HT 45 °C along with HOA inhibited PPO activity and prevented loss of antioxidant capacity, vitamin C and phenolic compounds in arils, in comparison with control and HT 55 °C. All treatments reduced the accumulation of anthocyanins, but HCA-treated arils lost more anthocyanins besides having worse a* colour parameter values. No significant differences in titrable acidity (TA) and total soluble solids (TSS) were observed between treatments. The combination of HOA and HT 45 °C enhanced the benefits of applying each treatment separately and could be useful to improve and extend postharvest life of pomegranate FC arils.

Summary Nectarine [Prunus persica (L.) Batsch] is a sought-after fruit due to its properties. In addition, minimally processed produces are more and more accepted by consumers. Four nectarine cultivars (‘Early Top’, ‘Nectaprima’, ‘Big Top’ and ‘Venus’) were selected to study their suitability for minimal processing. Samples were processed in a clean room at 8 °C, washed them in water (4 °C) and stored at 4 °C in modified atmosphere packaging. The samples were analysed at 0, 3, 6 and 9 days of storage, and quality parameters as well as functional compounds (polyphenols and polyphenol oxidase activity) were studied. Principal component analysis (PCA) was carried out to assess the relationship between nectarine cultivars and determined parameters. In conclusion, ‘Early Top’ and ‘Nectaprima’ cultivars showed the best quality results and therefore a promising suitability for fresh-cut processing. Nevertheless, the remaining cultivars should not be ruled out due to their functional content, advising additional conservation treatments for them.

Summary Our objective was to compare the effects of controlled atmosphere (CA) and modified atmosphere packaging (MAP) on fruit quality, chilling injury (CI) and pro- and antioxidative systems in ‘Blackamber’ Japanese plums. Matured fruit were stored for 5 and 8 weeks at 0–1 °C in normal air, CA-1 (1% O2 + 3% CO2), CA-2 (2.5% O2 + 3% CO2) and MAP (~10% O2 and 3.8% CO2). CA was more effective than MAP in retention of flesh firmness and titratable acidity during cold storage. Fruit stored in CA-1 showed reduced CI and membrane lipid peroxidation after 5 and 8 weeks of cold storage. Low O2 atmospheres appeared to limit the generation of reactive oxygen species (ROS) and their efficient scavenging through the concerted action of superoxide dismutase and peroxidase. The role of ascorbate–glutathione (AsA–GSH) cycle in the regulation of oxidative stress was also studied during and after storage in different atmospheres. In conclusion, optimum CA conditions delayed fruit ripening and CI through augmentation of antioxidative metabolism and suppression of oxidative processes.

Summary The effect of different modified atmosphere packaging conditions, 75 kPa O2 (high-oxygen atmosphere, HOA), 3.0 kPa O2 + 5.0 kPa CO2 (low-oxygen atmosphere, LOA) and passive atmosphere (PA) on the antioxidant properties of ready-to-eat honey pomelo slices stored at 4 °C was investigated. Both ascorbic acid content and antioxidant capacity underwent a significant depletion under HOA in comparison with LOA and PA. Total phenolic content among the samples stored under HOA and PA decreased significantly, but not for LOA. Moreover, HOA was more effective in maintaining the firmness of the slices. The hue angle values among different packaging atmosphere conditions were significantly affected, but chroma values were not. Both high oxygen and low oxygen concentrations inhibited the growth of spoilage microorganism of honey pomelo slices.

Summary The effects of chlorine (200 μL L−1), ozonated water (1 μL L−1) and gaseous ozone (0.7 μL L−1) on physicochemical attributes and microbial quality of minimally processed red bell peppers were studied. In all the experiments, O2 continuously decreased and CO2 concentration increased, the pH augmented and a significant softening was observed in all the fruits. By day 14, L* values decreased in all the fruits, with the greatest changes found in the chlorinated samples (approximately 12 units). Peppers treated with the aqueous solutions showed greater changes in the quality attributes with increasing washing times and especially when chlorine was used. The exposure for three min to gaseous O3 reduced the mesophiles, psychrotrophes and fungal populations of the fresh-cut peppers in 2.5, 3.3 and 1.8 log units, respectively. Combined with modified atmosphere, this could be an appropriate method to maintain the quality and extend the storage period of minimally processed red bell peppers.

Summary Completely matured tamr stage dates are widely available and consumed throughout the year. However, for some date varieties, the earlier khalal stage crunchy fruit is considered a premium product. This work examines the use of modified atmosphere packaging to extend the shelf life of khalal dates under refrigerated conditions. Modified atmosphere packaging with 10% or 20% CO2 in air was successful in reducing the rate of the ripening processes while control-packaged dates showed signs of ripening development such as significant weight loss and darkening in date colour (identified visually and as low lactic acid bacteria measurements at 18 and 27 days after packaging), similar to that observed in tamr stage fruit.

Summary Perforation of a film would otherwise have a low permeability is an alternative to obtain optimum oxygen and carbon dioxide concentration in modified atmosphere packages. In present study, gas exchange was studied through a macroperforated packet containing capsicum having different number of holes, 1–4, of diameter 0.3 mm at temperatures of 5 and 25 °C. A model combining the Michaelis–Menten kinetics to describe the respiration rate of the product with mass transfer equation to describe the gas transfer across the package provided a good fit to the experimental data. Its applicability was further validated in a dynamic test, subjecting a package to a variable temperature programme simulating conditions in distribution chains. Model showed good agreement between predicted and observed values for both storage conditions with constant temperatures and variable temperature conditions of distribution chain, as mean relative deviation modulus (E) value was

Summary Clingstone non-melting peach cultivars (Prunus persica L. Batsch) are used primarily for canning, but their processing as fresh-cut products is also of interest. Four clingstone peach cultivars (‘Andross’, ‘Babygold 8′, ‘Calante’ and ‘Romea’) were evaluated for their suitability for minimal processing (washing, peeling and slicing) followed by storage for 9 days at 4 °C in a modified atmosphere using microperforated films. Romea cultivar, which has low polyphenol oxidase (PPO) enzymatic activity, proved to be the most suitable cultivar for minimal processing, given its lower degree of browning as well as the results from a sensory evaluation. Maturity indicators varied slightly during storage at a different degree depending on cultivars. We have found that PPO activity and browning potential are adequate indicators for surface browning in fresh-cut non-melting peaches.

The effect of four different gas mixtures on several characteristics of Merino fresh lamb meat quality was studied. Merino lamb meat was packed under four different atmospheres (Batch 1: Ambient air; Batch 2: 70% O 2 + 30% CO 2 ; Batch 3: 80% O 2 + 20% CO 2 and Batch 4: 30% CO 2 + 69.6% Ar + 0.4% CO) and stored in darkness and under refrigeration (3 ± 1 °C) for 12 days. pH values and weight losses of lamb meat showed no significant changes during 12 days storage (P > 0.05) and were not affected by the different used atmospheres (P > 0.05). Lightness (L * ) was not significantly affected by gas atmospheres until day 12 of storage, lamb meat packed in contact with air (Batch 1) showing the lowest lightness (P 0.05).

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 O 2 and CO 2 (1%, 5%, 10%, 15% and 21 % of O2 with the balance N 2 , a mixture of 10% and 20% of carbon dioxide with the balance air and a mixture at 3% of O 2 and 15% of CO 2 with the balance N 2 ). 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 O 2 concentration from 21 % to 1% and by 44% with increasing the CO 2 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.

Summary The effect of −1.5 °C brine super-chilling on the quality of the modified atmosphere-packaged Lateolabrax japonicus fish fillets was studied. The result showed that the total viable mesophilic count (TVC) and H2S-producing bacterial count (HC) of samples were super-chilled, and then modified atmosphere-packaged (Sc + Map) were lower than that of Map (Samples were not super-chilled but modified atmosphere packaged), and values of total volatile base nitrogen (TVB-N), thiobarbituric acid (TBA), pH and myofibril fragmentation index (MFI) for Sc + Map increased more slowly than those for Map. Colour of skin and flesh of fish fillets was not affected by brine super-chilling, except the whiteness of the skin of fish fillets. Sc + Map could extend the shelf life of fish fillets for 4 days longer than Map.

Summary In this work, the combined effects of chitosan, modified atmosphere packaging (MAP) and packaging barrier properties on shelf life of fresh pasta is presented. In particular, all pasta samples were packaged under active and passive MAP in two different polymeric films with high and low barrier properties. In order to assess the influence of the variables described beforehand on the shelf life of pasta, the sensorial and microbiological quality has been monitored during storage. Results confirmed the antimicrobial properties of chitosan. Moreover, the findings recorded in this study suggest that the shelf life of fresh pasta is limited by the sensorial characteristics. Statistically significant differences between the shelf life of pasta packaged in low barrier and high barrier films were found. The best result was obtained for samples packaged in high barrier film, due to the ability of the packaging to maintain the gas headspace conditions during the storage.

Summary Mango puree is known to have good oxygen barrier properties. Therefore, mango film on its own might be useful to extend the shelf life of fresh-cut mango. In this study, fresh-cut mango was wrapped with mango film and packed in modified atmosphere packaging (MAP). Each package was stored at 30 °C or 5 °C and sensory evaluation was performed to determine its quality and shelf life. The shelf life of uncoated and coated fresh-cut mango pieces was 6 days for each at 5 °C and was 3 and 4 days, respectively, at 30 °C. The sensory evaluation indicated that coated fresh-cut mango was slower to produce an off-flavour and maintained better visual quality than uncoated mango at 30 °C. Nonetheless, coated fresh-cut mango was softer than uncoated mango because of the hydrophilic nature of the mango film. No significant difference in the oxygen and carbon dioxide concentrations was observed between coated and uncoated fresh-cut mango. Coating fresh-cut mango with mango film showed a similar effect to MAP in prolonging the shelf life of the fresh produce. The use of the coating will enhance fruit quality and lead to better acceptance by consumers.

The effect of different modified atmosphere packaging (MAPs) on physical, chemical, microbiological and sensory changes of sea bass fillets when stored at 4 °C and standard light conditions was investigated for up to 21 days and compared to a control batch stored in overwrap. Sea bass fillets were packed using different CO 2 and N 2 combinations (40% CO 2 ―60% N 2 ; 50% CO 2 ―50% N 2 ; 60% CO 2 ―40% N 2 ), and quality assessment was based on instrumental, chemical, microbiological and sensory analysis. The results showed that MAP extended shelf-life of sea bass fillets from 7 days (overwrap packaging) to 14 days. Drip loss, pH values and thiobarbituric acid reactive substances (TBARS) measurements were higher in overwrap samples but no differences (P ≤ 0.05) were found between MAP samples. Bacteria grew most quickly and showed higher counts in overwrap samples followed by 40% CO 2 ―60% N 2 ; 50% CO 2 ―50% N 2 and finally 60% CO 2 ―40% N 2 . Sensory analyses were in good relation with chemical and microbiological results establishing best scores and an extended shelf-life for MAP samples especially in MAPs with high CO 2 levels.

This study was carried out to determine the antioxidant activity of phytochemicals and plant extracts in fresh lamb patties. Quality indices such as colour (Hunter L* a* b*), lipid oxidation (TBARS) and pH were measured over an 8-day storage period. Resveratrol, citroflavan-3-ol, olive leaf extract and Echinacea purpurea were added to raw minced M. longissimus dorsi lamb patties, at concentrations ranging from 0-400 mg kg -1 lamb meat, stored in high oxygen modified atmospheres packs (75% O 2 :25% CO 2 ) for up to 8 days at 4 °C. The pH of the lamb meat was not significantly affected by the addition of the phytochemicals and plant extracts examined (P > 0.05). Resveratrol and citroflavan-3-ol decreased (P < 0.05) lipid oxidation in raw lamb patties during storage and increased a* values (P < 0.05), relative to controls. By contrast, olive leaf extract and Echinacea purpurea did not exhibit antioxidant activity or promote higher a* values relative to controls. Results obtained demonstrate potential for the development of functional meats using plant extracts such as resveratrol and citroflavan-3-ol.

Microbial characteristics under different atmospheres (vacuum, air, MAP 1 : 80% O 2 /20% CO 2 and MAP 2 : 5% O 2 /65% N 2 /30% CO 2 ) of poultry patties made of a mixture of ostrich, chicken and turkey meat were evaluated. The meat preparations were examined for changes in pH, colour properties (CIE L * , a * , b * ), headspace composition, and bacterial counts (total viable cell, psychrotrophs, Enterobacteriaceae, lactic acid bacteria, Staphylococcus spp., Brochothrix thermosphacta, Pseudomonas spp.). The use of a high O 2 atmosphere (MAP 1 ) quickly leads to a loss of the appealing red colour. A limited alteration occurred with use of MAP 2 and vacuum. For total viable counts a cell load higher than 8 log cfu g ―1 for the samples packaged in air, MAP 1 and MAP 2 at the end of storage was observed. Whereas, for the vacuum packed samples the cell load never reached values higher than 8 log cfu g ―1 . Enterobacteriaceae, B. thermosphacta and Pseudomonas spp. cell load was less with the vacuum (7.60, 5.06 and 7.17 log cfu g ―1 , respectively) and MAP 2 packaging (7.08, 5.60 and 7.40 log cfu g ―1 , respectively). However, the high microbial loads suggest that an improvement of the microbiological quality of poultry meat is necessary if the producers are going to propose this new meat preparation on the market.

Summary Chemical, microbial and sensory quality indices of raw and marinated sea urchin Paracentrotus lividus Lamark, 1816, were determined. Marinades were prepared using three different formulations and stored over a 75-day period at 6 °C, under vacuum and air (control) packaging conditions. Significant differences were found between chemical (pH, moisture, ash, NaCI, ammonia and lactic acid), microbial [pseudomonads (Ps), lactic acid bacteria (LAB) and yeast–moulds] and sensory analysis of three different marinated groups (P

Summary A study on the use of mild technologies to produce packaged fish hamburgers was presented. In particular, the antimicrobial effect of some natural compounds (carvacrol, eugenol, thymol, green tea extract, rosemary extract, grapefruit seed extract and lemon extract), at various concentrations (500–10 000 ppm), was screened in vitro against the main fish spoilage micro-organisms (Shewanella putrefaciens and Photobacterium phosphoreum). Lemon extract and thymol, in combination with modified atmosphere packaging, showed the greatest inhibition activity, therefore, thymol was subsequently used as an ingredient for producing fish hamburgers. Results pointed out that this combination is effective in controlling the growth of microbial species mainly involved in fresh fish spoilage; in particular, it significantly (P

Summary Fish oil (FO) enrichment of foods is relevant owing to the beneficial effects of omega-3 polyunsaturated fatty acids on human health. However, the susceptibility of FO to oxidation necessitates careful control to avoid this oxidation. In this study, energy bars were successfully supplemented with 5% FO. Heating of bars during baking did, apparently, not increase oxidation. Energy bars produced with neat FO were oxidatively unstable as measured by peroxide value, secondary volatile oxidation products and sensory analysis. Pre-emulsification of the FO with sodium caseinate in water offered similar protection towards oxidation as packaging the energy bars in modified atmosphere. These protection methods were although not as efficient as addition of FO as micro-encapsulated powder. Addition of the metal chelator ethylene diamine tetra-acetic acid (EDTA) (100–2000 ppm) to emulsified FO decreased the oxidative stability of the energy bars compared with the energy bars with emulsified FO but without EDTA.

Investigation of respiration rate of fresh produce, under different gas composition and temperatures, and respective mathematical modelling is central for the modified atmosphere packaging design. This work investigates the effect of temperature (4, 8, 12, 16, 20 °C) and gas composition (O 2 between 3 to 21 % and CO 2 between 0 to 15%) on respiration rate of whole mushrooms. Oxygen and carbon dioxide respiration rates increased significantly (3―4 fold) as the temperature elevated from 4 to 20 °C and were in the range of 13.23 ± 3.12 to 102.41 ± 2.132 mL kg ―1 h ―1 ) and 14.33 ± 1.56 to 97.02 ± 2.51 mL kg ―1 h ―1 ) respectively. Low O 2 and high CO 2 levels reduced O 2 consumption and CO 2 production rates of whole mushrooms on average by a circa 47―60% at all temperatures as compared to the respiration rate at ambient air. Mathematical models were developed for RO 2 and RCO 2 , by combining the Arrhenius and Michaelis― Menten uncompetitive equations. These models predicted well, O 2 consumption and CO 2 production rates of whole mushrooms as a function of both temperature and gas composition.

Summary This study evaluated the shelf life extension of a cheese cake subjected to modified atmosphere (MAP) and active packaging (AP). Cheese cakes were packaged under different N2/CO2 ratios (70/30 and 20/80) (MAP batches), by placing a sachet of an iron oxide-based oxygen absorber inside trays (AP batch) and with air (air batch). Changes in microbial growth, in-package gas composition, chemical–physical parameters including texture and sensory attributes were monitored for 48 days at 20 °C. AP allowed a mould-free cheese cake shelf life of 48 days, MAP extended the shelf life of samples packaged under 30% and 80% CO2 up to 14 and 34 days, respectively, whereas tarts stored with air spoiled after 7 days. MAP resulted in a significant increase in hardness after 14 days of storage, whereas AP tarts recovered the initial texture after 48 days. Panellists judged AP tarts over the acceptability threshold during the whole shelf life of cheese tarts.

In this work, the effect of temperature, oxygen, red coloration process and post-harvest storage time on the respiration rate of fresh-cut Annurca apples was studied to properly develop modified atmosphere packaging. Our results showed that the red coloration process and the post-harvest storage time did not affect the respiration rate or the respiratory quotient of fresh-cut Annurca apples in the range of temperature studied (5-20 °C). A Michaelis-Menten-type equation, with the model constants described by means of an Arrhenius-type relationship, was used for predicting respiration rate on varying the temperature and O 2 concentration in the head space. The maximal respiration rate (mL kg h -1 ) (RR max ) and the O 2 % corresponding to RR max 2 (K m ) values estimated at the reference temperature (12.5 °C), i.e. the average of the experimental temperature ranges, were, respectively, 6.77 ± 0.1 mL kg -1 h -1 and 0.68 ± 0.07% v/v, and the activation energy of the aerobic respiration rate of fresh-cut Annurca apples was estimated at 51 ± 1 kJ mol -1 . The model works well to develop a modified atmosphere for fresh-cut Annurca apples.

The effects of methyl jasmonate coupled with modified atmosphere packaging (MJ + MAP) on the quality and shelf life of mature green tomato (Lycopersicon esculentum Mill.) were investigated during cold storage at 5 °C. Tomatoes were treated with 10 -4 M MJ and packaged under 5 % O 2 /5%CO 2 /90%N 2 in a plastic bag. The effects of MJ + MAP were compared with control as well as heat treated (HT) samples. Control samples were tomatoes packaged under atmospheric air. HT samples were prepared by dipping tomatoes in hot water at 50 °C for 3 min and packaged under atmospheric air. The results showed that MJ + MAP and HT could delay ethylene production during tomato ripening and consequently slowed down the softening rate. MJ + MAP tomatoes showed better quality and less chilling injury (CI) symptoms than HT and control samples. Based on a nine-point score, shelf life criteria assumed that rejection would occur when the sensory attributes declined below 5. Control and HT overall acceptance scores were shown to fall below 5 scores after 3 and 6 weeks storage, while MJ + MAP had overall acceptance scores above 5 for up to 9 weeks. Control and HT samples could be stored for about 4 and 6 weeks, respectively, while MJ + MAP tomatoes could be stored for up to 9 weeks.

Summary Browning and other discolourations, softening, surface dehydration, water loss, translucency, off-flavour and off-odour development, as well as microbial spoilage are some of the most frequent causes of quality loss in fresh-cut products. Nowadays, the use of innovative modified atmospheres and edible coatings stands out among other techniques in the struggle for maintaining freshness and safety of fresh-cut fruits and vegetables. A few studies have demonstrated the effectiveness of these techniques when applied to different fresh-cut commodities. However, treatment and storage conditions for fresh-cut fruits are still being largely explored to better keep their fresh-like quality attributes. This review discusses the recent advances in the use of innovative modified atmosphere packaging (MAP) systems to maintain freshness of fresh-cut fruits and vegetables. Furthermore, special attention is devoted to the development of coatings that can be used as a complement or alternative to MAP.

The effects of ripeness at processing and packaging conditions on respiration, microbiological stability as well as colour and firmness of fresh-cut 'Flor de Invierno' pears were evaluated throughout storage. Although a 2.5-kPa O(2) + 7-kPa CO(2) atmosphere led to an inhibition of ethylene synthesis and carbon dioxide production compared with non-modified atmosphere packaging, the more advanced the ripeness stage at processing, the higher the physiological activity and thus, the higher production of carbon dioxide, ethylene and ethanol. A 2.5-kPa O(2) + 7-kPa CO(2) atmosphere inhibited bacterial growth, yeast and mould proliferation in mature-green pears but fast microbial growth was observed especially on ripe pears, under both packaging conditions. In conclusion, the shelf-life of ripe pears was reduced by increased respiration response to processing and accelerated microbial spoilage. Instead, pears processed in a partially ripe stage were suitable for conservation while gathering desired sensory attributes. Therefore, for commercial purposes, a shelf-life of 10 days was suggested for partially ripe fresh-cut pears packaged under a 2.5-kPa O(2) + 7-kPa CO(2) atmosphere

Summary The oxygen scavenging capacity of four commercially available iron-based oxygen scavengers was studied. Individual oxygen scavenger sachets were placed in pouches and filled with 1%, 2%, 6%, 12% or 22% oxygen, 40% carbon dioxide and balance nitrogen, and stored at 3 °C or 10 °C, with or without a drip pad infused with water and monitored over 24 h. The four scavengers all reduced oxygen from the packs at the oxygen concentrations and temperatures tested. However, for all of the conditions measured, the scavengers did not absorb their nominal capacity in the 24-h period. In anoxic modified atmosphere packaging of beef steaks, it is essential to reduce residual oxygen levels to below 0.05% as quickly as possible to minimise the formation of metmyoglobin. While the scavengers tested were effective in removing oxygen, the rate of removal would appear not to be fast enough to create the anoxic conditions required to prevent metmyoglobin formation in beef steaks, particularly in those cuts, which are highly susceptible to metmyoglobin formation. Reproducibility was also a critical issue for the scavengers, particularly at low oxygen concentrations. None of the scavengers had a coefficient of variation of less than 20% at the low oxygen concentrations. Therefore, to obtain consistent results, it is recommended that multiple scavengers be used.