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This study aimed to evaluate the effect of applying oxidized cassava starch-based edible coatings with addition of lemongrass essential oil emulsion on 'Palmer' mangoes stored under refrigeration. A completely randomized design was used, arranged in a 5 × 3 factorial scheme, with five types of coatings and three evaluation times. The evaluated postharvest quality parameters consisted of weight loss, pulp and peel firmness, biochemical transformations related to pigments, and pulp and peel coloration of mango. The application of edible coatings with a 0.9 % EO concentration resulted in delayed fruit ripening, evidenced mainly by a 7.25 % reduction in weight loss, a 29.23 % increase in soluble solids content, and a 24.15 % decrease in total chlorophyll, when compared to uncoated fruits, which showed 19.8 %, 48.66 %, and 82.00 %, respectively, over the storage period. This effect was also evident in the angle Hue (°h) measurement, with uncoated fruits showing a decrease of 32.2 %. The antimicrobial effect and absence of anthracnose symptoms were observed in the fruits in which the coating with 0.9 % EO was applied. Therefore, biodegradable coating with the addition of 0.9 % emulsion EO, can be used as postharvest treatments for maintenance quality of 'Palmer' mangoes during refrigerated storage. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2) is the most common gas used in modified atmosphere packaging (MAP) to protect packaged foods from spoilage and pathogenic microorganisms and thus extend the shelf life of food products. Non-destructive measurement of CO 2 concentration of the packaging headspace is of great interest as it could be used at various stages of the value chain, from outgoing goods inspection to storage tests and possible monitoring of the modified atmosphere at retail. Therefore, the aim of this work was to develop a measuring device operating non-destructively on closed MAP trays. Absorption measurement in the mid-infrared range at four different wavelengths proved to be a suitable principle for determining the CO 2 gas concentration in a closed packaging system: 4.26 μm (2347 cm−1) and 4.27 μm (2342 cm−1) in the range of the antisymmetric stretching vibration, as well as 4.45 μm (2247 cm−1) at the edge of the antisymmetric stretching vibration, and 3.95 μm (2532 cm−1) as a reference measurement outside the absorption band with a thermal infrared source. Measurement principle and setup - the measurement in the absorbing and non-absorbing range and the guiding of the thermal infrared (IR) emitter at a 45° angle through the corner of the tray - allows a measurement largely independent of tray shape, height, and packaged product. The measurement can also be used for pigmented and printed trays - except for carbon black pigments. Optical impairments of the packaging and labeled areas of the lidding film appeared to have the greatest influence on the measurement accuracy. The applicability of the measurement system was evaluated and successfully demonstrated using commercially available food packaging from a local supermarket by comparing the CO 2 gas concentrations yielded with those obtained using a destructive measurement device. • Successful construction of a non-destructive device for the measurement of the CO 2 gas concentration in polymer-based food packaging. • The guidance of the measurement path at a 45° angle enables a precise measurement (no filling-good interruption). • All packaging materials and pigmented packaging can be tested by the developed device – except carbon black pigment. • The usability of the device for different tray shapes and sizes was successfully demonstrated. [ABSTRACT FROM AUTHOR]

Internal browning is a common symptom of chilling injury (CI) of peach fruit during postharvest cold storage, leading to a significant loss in the marketplace. In this study, modified atmosphere (MA) storage was applied to mitigate the occurrence of CI in both 'Jinxiu' and 'Zhonghuashoutao' peach and the overall transcriptomic changes were profiled. In two cultivars, MA treatment elicited multiple chilling responses affecting production of reactive oxygen species (ROS) and lipid metabolisms, as well as jasmonic acid (JA), γ-aminobutyric acid (GABA) and proline synthesis, accompanied by accumulation of JAs (JA and JA-Ile), GABA and proline. Correlation analysis demonstrated that JAs and GABA served as significant regulators involved in cold tolerance under MA treatment. Weighted correlation network analysis (WGCNA) suggested that ethylene responsive factors (ERFs), WRKYs and NACs might serve as central transcription factors in the chilling-response pathway. Notably, PpERF61 was confirmed to activate the expression of JA biosynthetic genes Pp13S-LOX , PpAOS and PpOPR3 as well as GABA synthesis gene PpGAD. Taken together, this study unveils novel insights into the underlying mechanism of enhanced cold resistance in MA-treated peach fruit. • Modified atmosphere (MA) treatment alleviated chilling injury (CI) in peach fruit. • MA promoted accumulation of jasmonates (JAs) and γ-aminobutyric acid (GABA). • PpERF61 mediated alleviation of CI by MA via modulating JAs and GABA biosynthesis. [ABSTRACT FROM AUTHOR]

Low pressure storage (LPS) is a postharvest technology that has shown the potential to extend the storage life of various horticultural commodities. LPS addresses core postharvest challenges, such as desiccation, decay and senescence by creating an environment that maintains fully saturated air (i.e., high relative humidity) and ultra-low oxygen (ULO) conditions that can reduce respiration rates and suppress fungal growth. In this study, LPS chambers were evaluated for their ability to extend the storage life of blueberries (Vaccinium corymbosum L., cv. 'Draper'), compared to regular atmosphere (RA), across four different storage locations in the Pacific Northwest, USA. In three of the four locations, blueberries were field picked and loaded by hand, while at one location, fruit was loaded through mechanical harvesters. Following two weeks of storage, LPS chambers reduced blueberry respiration rates by 47 % from initial to lowest point, on average. Vacuum chambers filled with machine harvested fruit exhibited respiration rates 28 % higher than chambers with hand harvested fruit, although still sustained rates lower than at the initial loading (i.e., harvest). After five to eight weeks of storage, LPS chambers sustained nearly no weight loss, while fruit stored under RA conditions demonstrated weight loss between 2 and 7 % in the same period. LPS fruit was firmer, exhibited less incidence of superficial mold and fungal decay and better maintained titratable acidity than RA fruit. LPS chambers, when field loaded by hand, demonstrate significant potential in maintaining the at-harvest quality and condition of blueberries for up to eight weeks postharvest. Under these conditions, LPS can extend the storability of blueberries for eight weeks or more. Further investigation is required to determine the compatibility of extended LPS on machine harvested blueberries and with other commercially relevant cultivars. [Display omitted] [ABSTRACT FROM AUTHOR]

Disinfestation of insect pests is a crucial unit operation to save the quality of food grains during the storage. Several methods of disinfestation are available including chemical and non-chemical methods. However, the use of the chemical method is avoided because of its adverse effects on the environment and studies show that chemical methods have failed frequently in recent years. This paper reviews the recent applications of ionizing radiation, modified atmosphere, and dielectric heating for disinfestation of insect pests in stored grains. It is noted that the technologies mentioned have numerous advantages in applications, however, they also possess some inherent disadvantages that cause adverse effects to the grains being treated. To maximize treatment efficiency, the systematic integration of multiple non-chemical disinfestation methods with other unit operations is recommended. • Dielectric heating has an advantage of instantaneous treatment time. • Irradiation affects physio-chemical properties of grain. • Possibility of re-infestation exists after irradiation treatment. • Non-uniform temperature distribution in dielectric heating is major challenge. • Systematic integration of multiple non-chemical disinfestation methods is recommended. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate changes of the fatty acid profile in the intramuscular and subcutaneous fat as well as odor sensory evaluation of goose packaged under different conditions of modified atmosphere (vacuum and high-oxygen modified atmosphere of 80% O2 and 20% CO2 composition) and stored under refrigeration (4°C) for 11 D. Packaging in a high-oxygen modified atmosphere had a negative impact on goose meat quality due to the reduction of polyunsaturated fatty acids (PUFA), PUFA/saturated fatty acids (SFA) and the increase of SFA, which means a substantial loss of its nutritional value. Goose meat can be stored for 11 D without changes in the fatty acid profile, provided that a vacuum is used that limits oxygen exposure. At the end of storage, a better sensory evaluation of the odor intensity in the vacuum-packed samples was also observed in comparison to high oxygen modified atmosphere. Vacuum packaging turned out to be a better method for preserving fatty acid profile and the odor of goose meat during 11 D of storage. [ABSTRACT FROM AUTHOR]

• Post-harvest processing was optimized for flavor and consumer acceptability. • Volatiles associated with off-odors were elevated in stored fresh-cut watermelon. • Modified atmosphere packaging did not improve watermelon's perceived freshness. • Post-cut spray sanitation was detrimental to flavor and taste. • Volatile changes correlated to acceptability can be used to raise product quality. Shelf-life improvement of fresh-cut produce such as watermelon can be guided by optimizing flavor and consumer liking, while ensuring microbial quality. In this study, the impacts of postharvest processing and packaging technologies on consumer acceptability and flavor profiles of fresh-cut watermelon were evaluated. The treatments included post-cut sanitation spray (with and without), modification of the headspace gas composition (ambient and modified atmosphere), lidding film permeability (perforated and non-perforated), storage temperature (3 and 7 °C) and storage period (1, 6 and 8 d). Odor-active compounds of both fresh and stored watermelon were identified by olfactometry. Changes in key odor-impact volatile compounds were measured using solid phase microextraction-gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry. Changes in the volatile composition of samples stored at 3 °C were correlated to the consumer sensory scores for color, fresh appearance, odor, firmness, flavor, and taste. Fresh-cut watermelon packed in ambient air, sealed with non-perforated lidding film, and stored at 3 °C for both 6 and 8 d received the highest flavor and overall liking scores compared to modified atmosphere (5 %O 2 and 10 %CO 2). Further improvement of flavor freshness and overall acceptability was achieved when the post-cut sanitation step was removed. Results indicated that the shelf-life, as judged by overall perceived quality, can be increased from 6 to 8 d by manipulation of processing and storage conditions without compromising flavor and consumer acceptance. The study confirmed the usefulness of linking consumer acceptability to volatile measurement as a research tool to optimize product improvement. [ABSTRACT FROM AUTHOR]

Xyloglucan was extracted from Tamarindus indica (T. indica) seeds from industrial residue, presenting a glucose, xylose and galactose ratio of 1.41:1.31:1 respectively, with aim of elaborating a film. A Central Compound Rotatable Design (CCRD) with Xyloglucan variables from T. indica (XylTi) and Glycerol (Gly) was used to prepare the film. The films were analyzed for water vapor permeability, thickness, opacity, moisture, tensile strength, elongation at break, Scanning Electron Microscopy, thermogravimetric analysis and FT-IR. A significant (p < 0.05) influence of XylTi and Gly was observed, resulting in an increase in moisture (24.09%), tensile strength (20.70 MPa) and elongation at break (50.84%), with an increase in the independent variables. The best results for this work proposal were the film with 4.5% XylTi/1.5% Gly (T3). The T3 film was used in evaluating the efficiency of the optimized film for packaging cut-up 'Sunrise Solo' papaya, and the results showed a higher mass loss than the PVC film and statistically the same for ethylene and carbon dioxide production. It is concluded that films made with xyloglucan from T. indica seeds obtained from the residue of the fruit pulp industry presented good physical characteristics, highlighting the T3 elaboration, and are viable for manufacturing food packaging. Unlabelled Image • Films with xyloglucan from T. indica seeds has good physical characteristics and a potential for food packaging. • Film for cut-up 'Sunrise Solo' papaya, showed high production for ethylene and carbon dioxide when compared with PVC film. • Xyloglucan films have excellent thermal characteristics • Polysaccharides in producing films prolongs shelf life of foods and generally present good barrier properties. [ABSTRACT FROM AUTHOR]

Abstract Bacteria play a vital role in vegetable fermentation and preservation. However, the influence of a modified atmosphere (MA) on the storage of fermented vegetables has rarely been reported. In this study, the bacterial community composition and quality of fermented potherb mustard under carbon dioxide (CO 2) and nitrogen (N 2) conditions were investigated under 7% salt storage at room temperature (18–20 °C). Analysis of 16S rRNA gene sequencing showed dominant bacterial genera Halomonas and Psychrobacter were present under natural air conditions, while Lactobacillus was the major genus present under MA conditions. The bacterial communities differed significantly between MA and natural air conditions, and demonstrated wide diversity. In addition, titrable acidity (TAA) and nitrite contents were significantly reduced under MA conditions as compared to natural air condition. However, N 2 -MA resulted in TAA values that were rarely exceeding the ripe level 0.3% lactic acid. Thus, CO 2 -MA may represent a valuable approach to avoid the excessive acidification or incompletely ripe of the fermented vegetable. Present data also indicated better color and higher firmness of the fermented product under CO 2 conditions when compared to N 2 conditions. These results indicated that CO 2 -MA has a positive influence on bacterial community and the quality of fermented potherb mustard, which enlighted a new strategy for enhancing the quality of fermented vegetables. Graphical abstract Unlabelled Image Highlights • The bacteria community of fermented potherb mustard under controlled carbon dioxide (CO2) and nitrogen (N2) condition were investigated. • Halomonas and Psychrobacter were the main bacteria under natural air condition. • Lactobacillus was main bacteria in potherb mustard preserved under CO 2 and N 2 , and higher firmness in samples under MA condition than natural air condition. • The final fermented mustard product exhibited better quality characteristics under modified atmospheres of CO 2 than that of N 2. [ABSTRACT FROM AUTHOR]

Highlights • Nisin A inactivates over 90% of Listeria monocytogenes on lettuce. • Nisin A application to lettuce delays growth of Listeria monocytogenes by 5 d. • Type of modified atmosphere has limited effect on Listeria monocytogenes growth. • Bacterial community structure on lettuce changes radically during 7 d storage. Abstract Listeria monocytogenes poses a risk to minimally processed ready-to-eat foods such as lettuce due to its ability to grow under refrigeration conditions. Since many natural anti-listerial products render Iceberg lettuce unsuitable for consumption within 2 d of storage, this study investigated the efficacy of Nisin A as anti-listerial agent and its sensory impact on lettuce. In addition, the evolution of the bacterial community on fresh-cut lettuce was monitored for the duration of storage. In-vitro assays confirmed the efficacy of Nisin A to inhibit growth of a three strain mix of L. monocytogenes in model atmospheres and air. The L. monocytogenes strain mix was added to lettuce that was subsequently treated either with Nisin, L. lactis DSM20729 (a Nisin A producer) or was kept without inoculation. Incubation took place at 4 and 8 °C under various atmospheres. On days 0, 2, 5 and 7, L. monocytogenes was enumerated on selective agar and a sensory panel graded the lettuce on visual appearance. At 4 and 8 °C a 10 to 100-fold reduction of L. monocytogenes growth was achieved with 5 mg kg−1 Nisin over a seven-day period, while lettuce kept an acceptable sensory appearance over the first 5 d. Direct application of L. lactis had no detectable effect on L. monocytogenes growth in situ. The bacterial community structure changed substantially from each sampling day to the next over the seven days of incubation. However, Pseudomonadaceae with the genus Pseudomonas were most abundant at all times and increased in relative abundance to over 90% by day 7. In conclusion, the application of Nisin A to minimally processed vegetables like lettuce seems to be a viable alternative to reduce and delay growth of pathogen L. monocytogenes , while not impacting the sensory appearance for 2–5 d. [ABSTRACT FROM AUTHOR]

Essential oils of the species Allium cepa (OEC) and Allium sativum (OES) were investigated in isolation and in combination with modified atmosphere packaging (MAP) in the proportion of 60% CO 2 + 30% N 2 + 10% O 2. The objective was to evaluate the performance of ten treatments of marine shrimp Litopenaeus vannamei , stored for 15 days under refrigeration (4 ± 2 °C). Essential oils were equally effective against the visible metabolic activity of gram-positive bacteria, but OES indicated significantly higher concentrations (p < 0.05) of total phenols, with higher anti-DPPH activity and LD 50 in bioassay with Artemia salina Leach. The combination of treatments improved the technological and sensorial quality of marine shrimp L. vannamei. Color changes and multiplication of pathogenic microorganisms were delayed, highlighting the MAP +2% OEC and 0.5% OES treatments, as well as the shelf life that was extended to at least 15 days under refrigerated storage. • Allium cepa and Allium sativum essential oils were combined with modified atmosphere. • Treatments improved the quality of the marine shrimp Litopenaeus vannamei. • Color changes and multiplication of pathogenic microorganisms were delayed. • Shelf life has been extended to at least 15 days under refrigerated storage. [ABSTRACT FROM AUTHOR]

This work aimed to prepare a blend of sulfonated poly ether ether ketone (SPEEK) into polyvinylidene fluoride (PVDF) to develop a modified film suitable as a modified atmosphere package (MAP) for broccoli. The miscibility between SPEEK and PVDF was determined by homogeneous micro-morphology and single glass transition temperature (Tg). Results revealed that the blended material had good antifouling ability, moderate porosities and appropriate gas selectivity. Films prepared by the blended material were used as equilibrium MAP to maintain quality of broccoli samples during storage. With ∼ 300 g of broccoli in ∼ 2.1 L of internal volume, films prepared with 50% ( w/w ) SPEEK and 50% ( w/w ) PVDF maintained an internal atmosphere of 8.2% CO 2 and 2.0% O 2 in MAP. In this atmosphere, acceptable sensory score of the broccoli was maintained for 25 d, compared with only ∼ 15 d for control samples. The MAP also reduced loss of green color and maintained texture and chemical composition of broccoli. The results of this study reveal that the prepared gas promoter-gas barrier blending packaging has promise for preservation of harvested fresh vegetables. [ABSTRACT FROM AUTHOR]

The objective of the work was to investigate the effect of modified atmosphere (MA) packaging (high oxygen modified atmosphere and vacuum) on pH, water holding capacity and cooking loss of raw goose meat, and on the sensory assessment and shear force of roasted meat. Samples refrigerated at 1°C were tested within 24 h after slaughter (unpacked meat) and on d 4, 7, 11, and 14 of storage (modified atmosphere or vacuum packed meat). The type of atmosphere used in packaging determined the functional properties of goose meat such as: pH, WHC, cooking loss and shear force. This is important from both the culinary and technological viewpoint. At the end of storage the meat packed in MA (consisting of 80% O2, 20%CO2) had higher cooking loss, lower pH values, and water holding capacity in comparison to samples stored in vacuum. The type of atmosphere influenced the sensory descriptors (characteristic odor and flavor, tenderness, juiciness and general evaluation) of roasted meat. Samples packed in MA did worse during sensory assessment with respect to odor and flavor, tenderness, juiciness and general assessment. Thus meat stored under modified atmosphere showed lower productivity and was less tender and juicy. The goose breast muscles packed in vacuum proved to be better suited for consumption and processing as compared to those packed in high oxygen MA. [ABSTRACT FROM AUTHOR]

Minimally processed fresh-cut (MPFC) fruit products are an important source of functional ingredients, and increased consumers’ demand boosted an expansion of this segment of food industry. Apples ( Malus sp.) are commonly cultivated fruits and processed to MPFC products. Their low shelf life is the main obstacle for gaining maximum nutritive and economic benefits. Enzymatic, metabolic, and other physiological processes induce changes that render the product spoiled and decrease the storage and marketability life of MPFC fruits. Such spoilage can be controlled by modified atmosphere packaging (MAP), but intrinsic influences of numerous MAP factors are not clearly elucidated. Microbial growth adds another layer of complexity to MAP. Mathematical modeling can successfully predict microbial growth and spoilage, hence saving production cost and provide better control over the production chain. In this sense, this review provides an overview of MAP’s factors that influence the quality of stored MPFC products. Focus was placed on apples and development of mathematical models that can be useful for prediction of their spoilage during storage and subsequently their shelf-life. [ABSTRACT FROM AUTHOR]

Strong off-odor development is still one of the major problems associated with quality loss of baby spinach stored in MA with low O 2 and high CO 2 . Freshness has been generally evaluated by sensory techniques that allow the description of aromatic profiles but it does not identify the responsible compound(s). An approach including sensory analysis and Gas Chromatography-Mass Spectrometry (GC–MS)/Gas Chromatography-Olfactometric (GC-O) techniques were applied to elucidate the complex combination of volatile organic compounds (VOCs) responsible for the off-odor perception of intact baby spinach without generation of new volatiles due to tissue manipulation. After 14 days, levels of low O 2 and high CO 2 (0.3 and 9.3 kPa, respectively) were achieved and off-odors development was detected. After GC–MS/GC-O analysis, there were 39 main compounds with olfactory activity, identified as alcohols associated with lipid peroxidation or LOX pathway; sulfur compounds from amino acid degradation; and alkanes from lipid autoxidation processes or carotenoid degradation. Odor-active compounds were grouped into the six odor categories as described by the sensory panel, with rotten and fishy being the strongest odors perceived after storage. The isolated VOCs grouped in the rotten descriptor were the alcohols 1-pentanol, ( Z )-3-hexen-1-ol and 1-octen-3-ol, and the sulfur compounds methanethiol and dimethyl disulfide. A compound responsible for fishy notes was dimethyl sulfide but some evidence indicated that amine compounds with low odor thresholds could be also implicated. Since sulfur compounds were perceived by all sniffers and easily detected by mass spectrometry, they may be good candidates as biomarkers of off-odors in baby spinach. [ABSTRACT FROM AUTHOR]

Rosemary essential oil (REO) contains bioactives having antioxidant and antimicrobial properties. This work investigated the effect of REO combined with modified atmosphere packaging conditions (MAP), in our case, aerobic, vacuum or high O 2 , to extend the shelf life of beef. Beef slices were wrapped in special three-layer sheets of packaging material, some with a coating of REO (active packaging, AP), and some without REO (non active packaging, NAP), and stored at 4 °C for 20 days. The use of REO proved efficacious in every storage condition, as seen in the lower counts of psychrotrophics, Brochothrix thermosphacta, Pseudomonas spp., and Enterobacteriaceae in AP meat compared to NAP meat. Sensory and colourimetric analyses showed that the best packaging conditions were high-O 2 atmosphere in combination with REO. Based on microbiological data, shelf life of beef was 5–6 days for AP samples packaged under aerobic conditions and 14–15 days for AP samples in high-O 2 conditions. [ABSTRACT FROM AUTHOR]

The objective of the work was to investigate the color and lipid oxidation changes of goose breast meat packaged in vacuum and modified atmosphere (MA) conditions consisting of 80% O2, 20% CO2, and stored in refrigerated conditions at 4 C. Color stability was monitored by determining total heme pigments concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L* a* b*, and sensory evaluation of the surface color. Lipid stability was measured by determining thiobarbituric acid reactive substances (TBARS). The samples were examined in 24 h after slaughter (unpacked muscles) and on d 4, 7, 9, 11 of storage (muscles packed in vacuum and in MA). Through the time of storage, samples packed in MA had higher TBARS values in comparison to the meat packed in vacuum. For samples packed in two types of atmospheres, the total pigments concentration decreased gradually within 11 d of storage. It was observed that relative metmyoglobin concentration increased whereas relative oxymyoglobin concentration decreased in total heme pigments in the MA stored muscle. The relative concentration of all three myoglobin forms sample packed in vacuum remained unchanged. The color parameters (L*, a*, b*) did not change for 11 d of storage for the vacuum packed meat. The value of the color parameter a* decreased and the value of the color parameters L* and b* increased in the samples packaged in MA. The data prove that if you store goose meat in MA (consisting of 80% O2, 20% CO2) or vacuum, the unchanged surface color is preserved for 9 and 11 day, respectively. Vacuum appears to be a better method as regards the maintaining of lipid stability in goose meat. [ABSTRACT FROM AUTHOR]

The influence of a selection of minimal processing techniques (sanitizing wash prior to packaging, modified atmosphere, storage conditions under light or in the dark) was investigated in relation to the survival of, attachment to and internalization of enteric pathogens in fresh produce. Cut Iceberg lettuce was chosen as a model for fresh produce, Escherichia coli O157:H7 ( E. coli O157) and Salmonella enterica were chosen as pathogen models. Care was taken to simulate industrial post-harvest processing. A total of 50 ± 0.1 g of fresh-cut Iceberg lettuce was packed in bags under near ambient atmospheric air with approximately 21% O 2 (NAA) conditions or equilibrium modified atmosphere with 3% O 2 (EMAP). Two lettuce pieces inoculated with E. coli O157 BRMSID 188 or Salmonella Typhimurium labeled with green fluorescent protein (GFP) were added to each package. The bags with cut lettuce were stored under either dark or light conditions for 2 days at 7 °C. The pathogens' capacity to attach to the lettuce surface and cut edge was evaluated 2 days after inoculation using conventional plating technique and the internalization of the bacteria was investigated and quantified using confocal microscopy. The effect of a sanitizing wash step (40 mg/L NaClO or 40 mg/L peracetic acid + 1143 mg/L lactic acid) of the cut lettuce prior to packaging was evaluated as well. Our results indicate that both pathogens behaved similarly under the investigated conditions. Pathogen growth was not observed, nor was there any substantial influence of the investigated atmospheric conditions or light/dark storage conditions on their attachment/internalization. The pathogens attached to and internalized via cut edges and wounds, from which they were able to penetrate into the parenchyma. Internalization through the stomata into the parenchyma was not observed, although some bacteria were found in the substomatal cavity. Washing the cut edges with sanitizing agents to reduce enteric pathogen numbers was not more effective than a rinse with precooled tap water prior to packaging. Our results confirm that cut surfaces are the main risk for postharvest attachment and internalization of E. coli O157 and Salmonella during minimal processing and that storage and packaging conditions have no important effect. [ABSTRACT FROM AUTHOR]

Background Although CO 2 gas is useful for the modified-atmosphere packaging of foods, excess CO 2 accumulation in a package may be detrimental to the quality of the product and/or the integrity of the package, particularly in the case of CO 2 -producing foods, such as fermented foods and fresh produce. In those cases, including CO 2 scavengers in food packages is beneficial for preserving the food quality and package integrity. Scope and Approach The common mechanisms that are exploited for CO 2 absorption in food packages are chemical reactions and physical adsorption. The CO 2 absorption capacity and absorption kinetics of chemical and physical absorbers were examined and reviewed with respect to their proper use in packages of CO 2 -producing foods. The applications of CO 2 scavengers in food packages were examined in terms of the benefits achieved and their efficacy. Key Findings and Conclusions The CO 2 production characteristics and desired atmospheric conditions of foods must be established and tuned to the thermodynamic and kinetic properties of CO 2 absorbers sometimes in combination with the gas transfer behaviour of the package layer. The combined or synergistic use of CO 2 scavengers with other active packaging tools may be the direction for further research improving food quality preservation. [ABSTRACT FROM AUTHOR]

Fruit surface coatings reduce gas exchange and modify the internal atmosphere composition. However, to set a safe internal atmosphere target, an optimum starch concentration must be determined for each fruit. To avoid the risk of anaerobiosis, surface coatings must be designed considering specificities in the structure and physiology of the product to be coated, properties of the coating solution, and coating-fruit surface interaction. In this study, it was developed a method for estimating the effective proportion of a starch-based coated surface using digital image processing. The starch-coated areas were stained with iodine solution and quantified using coated/uncoated region color image segmentation. To understand the need for surfactant and the optimal temperature for adding surfactant, 3% cassava starch coatings were prepared with and without Tween 40® as a surfactant. Tween 40® was added into starch matrix coating at 18 and 60 °C. These coatings were applied to bananas, mandarin oranges, and bell peppers. The coatings without and with Tween 40® (added at a warm coating) showed weak adhesion to the fruit peels, especially those with high cutin and wax levels (mandarin and pepper). However, adding Tween 40® to a cooled coating enhanced its adhesion regardless of the structure of the fruit peel surfaces. Thus, these results show for the first time that the temperature for adding the surfactant markedly affects the coated percentage area of fruits. Following this, cassava starch coatings at 1.5, 2.0, 2.5, and 3.0% with Tween 40® added at 18 °C were tested on banana and papaya. The internal levels of O 2 and CO 2 were assessed to target safe, coated fruit internal atmosphere. Increasing the starch coating content increased the fruit's coated area, resulting in a decrease in O 2 and increase in CO 2 internal levels. The internal atmosphere build-up with the highest starch content (3.0%) and Tween 40® for papaya was O 2 (5.8 kPa) and CO 2 (6.6 kPa), which is suitable for postharvest papaya storage. However, for bananas, this level of starch coating resulted in very low O 2 (1.9 kPa) and high CO 2 levels (48.6 kPa). These results demonstrate that the internal atmosphere build-up for coated fruits with similar starch matrix coating contents is fruit-specific. • An approach for estimating fruit's starch-coated area was developed. • Image segmentation of stained starch-coated fruit was used to assess the coated area. • Cooling starch matrix before adding surfactant enhances fruit coated surface area. • Internal atmosphere build-up at similar starch coating content depends on fruit type. [ABSTRACT FROM AUTHOR]

Controlling storage atmosphere is a key factor for delaying postharvest fruit quality loss. The objective of this study is to evaluate its influence on physico-chemical, sensorial and nutritional quality attributes of two tomato fruit cultivars (Delizia and Pitenza) that respectively have a short- and long-storage life. To that end, the effect of two types of bags with different gas permeability, combined or not with an ethylene sorbent, on tomato organoleptic and nutritional properties were compared during fruit storage at 13 °C. CO 2 and O 2 were critical factors for controlling tomato postharvest behaviour. Weight loss, firmness, color and visual quality were only affected by bag permeability just as total sugar content and acidity for Pitenza tomatoes. ( trans )-2-Hexenal also appears to be related with CO 2 and O 2 levels. Lycopene, total phenols (TP) and ascorbic acid (AA) contents were also affected by the packaging form and the storage length. Ethylene removal in combination with MAP led to a higher content in TP and AA in the short-life tomato cultivar. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effect of different aging temperatures prior to freezing on quality attributes of frozen/thawed lamb loins. The loins ( M. longissimus lumborum ; n = 32) were randomly allocated to one of the four different aging/freezing treatments: aged only (− 1.5 °C for 14 days) and aged (− 1.5 °C for 14 days, 3 °C for 8 days, or 7 °C for 8 days) then frozen/thawed loins. The loins aged at elevated temperatures (3 °C or 7 °C) for 8 days had equivalent shear force, protein degradation and purge loss values compared to the loins aged at − 1.5 °C for 14 days ( P > 0.05). However, significantly higher drip loss and less color stability were observed in the loins with increasing aging temperatures compared to the loins aged at − 1.5 °C. These results suggest that application of elevated aging temperatures could shorten required aging periods prior to freezing, while not adversely affecting tenderness and purge loss of frozen/thawed meat. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of modified atmosphere packaging (MAP) on fresh prickly pear ( Opuntia albicarpa ). Unpacked prickly pears (control) and packaged under passive (20.3 ± 0.1% O 2 and 0.03 ± 0.0% CO 2 ) and active (6.25 ± 0.1% O 2 and 3.65 ± 0.1% CO 2 ) atmospheres were stored at three temperatures (4, 10, and 27 °C). Fruit were evaluated for weight loss, color, firmness, bioactive compounds, microbial load, and sensory characteristics every 10 d for 40 d. Prickly pears, stored under modified atmospheres at 4 and 10 °C. Experienced a delayed weight loss by 1.0% and a total color change (Δ E ) of 13.7 was observed. In general, the firmness of prickly pears stored under modified atmospheres was lower than for unpacked fruit. During storage, phenolic compounds increased in fruit under all storage conditions. Microbial growth increased in fruit packaged in modified atmosphere; however, at low temperatures the microbial growth decreased. Sensory evaluation judges detected changes in color and softening of fruit during storage. [ABSTRACT FROM AUTHOR]

Fresh-cut swede ( Brassica napus L. var . napobrassica (L . ) Rchb.) and turnip ( Brassica rapa L . ssp. rapifera Metzg.) in modified atmosphere packaging (MAP) were stored for 5 or 10 d, at 5 °C or 10 °C. Two passive and one active (flushed with 5% O 2 at sealing) modified atmospheres were tested. Vitamin C content was not influenced by the experimental parameters. The content of total sugar decreased during storage for both vegetables, and significant effects of time, temperature and atmosphere were observed for glucose, fructose and sucrose. Total aliphatic and indolic glucosinolates increased in swede during storage, while for turnip total aliphatic glucosinolates decreased and total indolic glucosinolates increased. Atmosphere composition affected glucosinolates, and the response varied between individual glucosinolates. Taste and flavour were more influenced by time and temperature, than by atmosphere in both vegetables. However, modified atmosphere with low O 2 concentration reduced discolouration related changes, especially for turnip. Positive correlation was observed between sugar content and sweet taste for both vegetables. Sweet and bitter tastes were negatively correlated for swede. Low temperature and short storage time were the most important criteria to prevent changes of appearance, odours, taste and flavours, and contents of sugar and glucosinolates of fresh-cut swede and turnip. [ABSTRACT FROM AUTHOR]

This study investigated the effect of premature browning (PMB) on the survival of Escherichia coli O157:H7 in beef hamburgers after cooking with respect to interior colour of the hamburger and recommendations to cook hamburgers to a core temperature of 71 °C. Assessment of doneness by visual inspection or measurement of internal temperature was compared in terms of survival and the increased relative risk of illness due to PMB was estimated. At the last consume-by-day, hamburgers made from minced meat packaged in 80/20 O 2 /CO 2 (MAP hamburger) and from meat minced at retail packaged in atmospheric condition (control hamburger) were inoculated with a gfp -tagged strain of E. coli O157:H7 ( E. coli O157:H7 gfp +). Hamburgers were cooked for different times during assessment of the core temperature every 30 s and cut in halves after cooking. Doneness was evaluated based on visual judgement of the internal colour using a score chart (C-score) from ‘uncooked’ (score 1) to ‘tan with no evidence of pink’ (score 5). An alternative five point score chart (TCC-score) including texture of the meat, clarity of meat juice and internal colour was also developed. Enumeration of viable E. coli O157:H7 gfp + in cooked hamburgers was based on fluorescent colonies recovered from plates. Results showed that MAP hamburgers developed PMB when compared with controls ( P = 0.0003) and that the shortest cooking time for the highest C-score was 6 and 11 min for MAP and control hamburgers, respectively. The mean temperature in the MAP hamburger was then 60.3 °C. The TCC-score reduced the difference between MAP and control hamburgers. It was also shown that the survival of E. coli O157:H7 gfp + was highest in MAP hamburgers. The predicted absolute risks for illness were highest for MAP hamburgers for all C-scores and the relative risk associated with PMB increased with doneness. For a C-score of 4 (slightly pink) the predicted relative risk for illness was 300 times higher for MAP hamburger than for controls. A variable pathogen reduction was observed when cooking hamburgers to temperatures of 70–76 °C (the 5th and 95th percentile range was around 3.3 log CFU). The lower reductions, at the 5th percentile, may, depending on initial contamination levels, not be enough to ensure sufficient and safe inactivation of E. coli O157:H7. Efforts to inform consumers about PMB in minced meat packaged in high oxygen packages (≥ 60% O 2 ) are needed with the aim to make consumers use thermometers correctly or at least not determine doneness based only on meat colour. [ABSTRACT FROM AUTHOR]

The overall quality, titratable acidity, total solid soluble, total polyphenol, anthocyanin content, antioxidant activity, sugar content and juice color of ready-to-eat arils of ‘Primosole’ pomegranate processed at harvest and after 30 or 60 days of storage of whole fruit at 5 °C and 90% RH was assessed. Minimally processed arils were packaged in polypropylene trays (150 g each), wrapped with a polypropylene film to generate a passive modified atmosphere and stored at 5 °C and 90% RH for 10 days. In-package CO 2 was lower for those arils obtained from fruit with longer storage time while O 2 concentrations increased. Slight or not significant changes were detected in chemical and physical parameters during the 10 days of shelf-life of packaged arils, regardless the storage time of whole fruit, even when physiological disorders of the peel significantly reduced the commercial value of whole fruit along storage. Similarly, changes in sensory analysis were negligible and did not affect the eating quality. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2) plays an important bacteriostatic role in high-oxygen modified atmosphere packaging (HiOx-MAP). This study aimed to explore the influence of CO 2 on the volatile organic compounds (VOCs) profile in HiOx-MAP beef steaks and assess the changes in VOCs associated with microbiota dynamics during 20-days of chilled storage. Compared to control MAP (CMAP: 50% O 2 /50% N 2), CO 2 -enriched MAP (TMAP: 50% O 2 /40% CO 2 /10% N 2) rendered steaks with desirable appearance and odor freshness during storage through inhibiting bacterial growth and reducing the accumulation of acetoin, 2-ethyl-1-hexanol, 1,3-butanediol, diacetyl and 2-heptanone (P < 0.05). 1-Octen-3-ol and 2-ethyl-1-hexanol were main VOCs in TMAP steaks and were positively related to Brochothrix thermosphacta levels. Acetoin and 2-ethyl-1-hexanol could be used as potential spoilage indicators in CMAP steaks, which were positively related to B. thermosphacta and Pseudomonas levels. Overall, the desirable odor freshness of TMAP steaks was mainly attributed to the CO 2 -inhibitory effect on the off-odor VOCs production correlated with B. thermosphacta , Pseudomonas and Serratia growth. • The inhibitory effects of CO 2 on beef spoilage in HiOx-MAP were studied. • CO 2 restricted microbiota growth and VOCs associated with off-odors. • 1-Octen-3-ol and 2-ethyl-1-hexanol were abundant VOCs in CO 2 enriched HiOx-MAP. • Acetoin and 2-ethyl-1-hexanol were the potential spoilage markers in non-CO 2 MAP. • CO 2 reduced VOCs associated with Brochothrix thermosphacta , Pseudomonas and Serratia growth. [ABSTRACT FROM AUTHOR]

The aim of our research was to determine the presence and examine the change in total number of Enterobacteriaceae in trout and carp cuts packed in vacuum and modified atmosphere. To conduct the study, three sample groups of cleaned trout and carp cuts were formed. The first two groups were packaged in modified atmospheres with different gas ratios: 60%CO 2 +40%N 2 (I group) and 40%CO 2 +60%N 2 (II group), whereas the third group of fish cuts were vacuum packaged. Our results suggest that modified atmosphere packaging of fresh fish with an appropriate percentage of CO 2 might reduce the risk of poisoning people with Enterobacteriaceae . [ABSTRACT FROM AUTHOR]

The cowpea bruchid ( Callosobruchus maculatus ) is the most important storage pest of grain legumes and comprises geographically distinct strains. Storage under a modified atmosphere with decreased O 2 content represents an alternative to chemical fumigants for pest control of stored grains. In this study, we compared reproduction, development and survival, as well as genome size of bruchid strains from South India (SI), Burkina Faso (BF), Niger (CmNnC) and the United States (OH), reared on mung bean ( Vigna radiata ). Fecundity and egg-to-adult duration varied significantly among these strains. Notably, strain BF had the highest fecundity, and strain SI displayed the fastest development whereas strain OH was the slowest. Differences in adult lifespan among strains were only detected in unmated but not in the mated group. Genome size of SI females was significantly larger than that of OH females, and for all four strains, the female genomes were larger than those of their corresponding males. Furthermore, we studied effects of exposure to 1% O 2 + 99% N 2 on strains SI and BF. Mortality caused by hypoxia was influenced by not only developmental stage but also by insect strain. Eggs were most sensitive, particularly at the early stage, whereas the 3rd and 4th instar larvae were most tolerant and could survive up to 15 days of low O 2 . Strain SI was slightly more resistant than BF in egg and larval stages. Proteolytic activity prior to, during and after hypoxia treatment revealed remarkable metabolic plasticity of cowpea bruchids in response to modified atmosphere. [ABSTRACT FROM AUTHOR]

Medlar ( Mespilus germanica L. cv. Istanbul) fruit were stored in palliflex controlled atmosphere storage systems of 21% O 2 + 0.03% CO 2 (PL-1, control), 2% O 2 + 5% CO 2 (PL-2), 3% O 2 + 10% CO 2 (PL-3) and modified atmosphere packaging (MAP) at 0 °C for 60 days to determine the effects of different O 2 and CO 2 concentrations on physiological properties, quality attributes and storability. Every 15 days, three replicates of each treatment were evaluated for weight loss, fruit firmness, decay, external browning index, skin color, pH, titratable acidity, total soluble solids, total phenolics, total flavonoids, total condensed tannins, ascorbic acid, antioxidant activity and organic acid and sugar contents. Taste analysis of the fruit was performed after 30, 45 and 60 days of storage. The CO 2 and O 2 concentrations created by the MAP stabilized at 7% and 14%, respectively. Weight loss of fruit stored in MAP was lower (<0.4% at 60 days) than for other treatments. Off-flavors were not detected in any treatment. Storage of medlar fruit under PL-3 was the least effective treatment in delaying fruit ripening (flesh firmness). The incidence and severity of browning, loss of skin color ( Ch °) and retaining acceptable taste during 60 days were found the most effective in PL-2 and PL-1 compared to other treatments. Fruit pH increased and titratable acidity decreased during the storage period. Total soluble solids and sugar contents first increased then decreased in all treatments by the end of storage. The fruit stored in PL-2 had higher titratable acidity, total soluble solids and sugar contents than fruit stored in PL-1, PL-3 and MAP at all evaluations. Concentrations of total phenolics, total flavonoids, total condensed tannins, ascorbic acid, associated antioxidant activity and organic acids were affected by the storage atmosphere, decreased during storage. The concentrations of total phenolics, total flavonoids, and antioxidant activity were found the highest in PL-2, PL-1 and MAP treatments, respectively. However, in terms of ascorbic acid and total condensed tannins retention, PL-2 was the most effective treatments. The results indicated that 60 days storage of medlar fruit in the palliflex storage system at 0 °C maintained physiological and biochemical properties of medlar fruit. [ABSTRACT FROM AUTHOR]

Highlights: [•] 9 treatments were tested to identify the best for ‘Laiyang’ pear during cold storage. [•] 0.5μL/L 1-MCP plus micro-perforated film showed the best effects on fruit qualities. [•] 0.5 and 1.0μL/L 1-MCP did not enhance the susceptibility to CO2 injury of ‘Laiyang’ pear. [•] 0.5μL/L 1-MCP plus micro-perforated film maintained flesh color by inhibiting its senescence. [ABSTRACT FROM AUTHOR]

Highlights: [•] The late instar larvae of cowpea bruchid were most resilient to hypoxia. [•] CO2 significantly increased the mortality of cowpea bruchid caused by hypoxia. [•] CO2 promoted premature opening of windows in the 4th instar larvae when exposed to hypoxia. [Copyright &y& Elsevier]

[Display omitted] • Quality and volatile profile of fruits were monitored in an active packaging. • Relationships among bacterial community, atmosphere and volatiles were studied. • Off-flavor and sesquiterpenes in longan was related to spoilage genera. • Hypoxia increased ethyl esters decreased methyl and hexyl esters in strawberry. The potential impacts of active packaging on the volatile composition of fruits during preservations largely associated with consumers' acceptance, yet was barely investigated. In this work, a biopolymer-coated polyethylene active film was developed and its effects on qualities and volatile compositions of fruits with different respiration rates were comprehensively investigated. Underlying reasons for the effect of active packaging on volatile composition change of fruits were elucidated through revealing ternary relationship among the packaging-shaped bacterial community, modified atmosphere and volatiles. Off-flavor production was reduced and more sesquiterpenes (α-cubebene, copaene, β-caryophyllene, α-caryophyllene, d-amorphene) were reserved for longan packaged with active film, due to its antimicrobial and moisture absorption ability, as leading contributors to the selective inhibition on spoilage bacteria genera including Zymobacter , Gluconobacter and Pantoea. Whereas volatile profile of strawberry with high respiration rate was more actively affected by the modified atmosphere induced by packaging, instead of the bacterial community, where hypoxia (<2% O 2) led to the accumulation of ethyl esters (0.154–0.184 μg/g) that conferred off-flavor but decreased production of methyl (0.172–0.367 μg/g) and hexyl esters (1.26–1.89 × 10−2 μg/g) that represented typical fruity aroma. This work adds new knowledges on impacts of active packaging on the volatile profile of fruits and would provide guidance to smart design of active packaging for preservation of aromatic fruits. [ABSTRACT FROM AUTHOR]

Forty-eight Churra ewes and their suckling lambs were assigned to four dietary treatments: control (CTRL), VIT-E (500 mg kg-1 TMR vitamin E), GP-5 (5% grape pomace) and GP-10 (10% grape pomace). After slaughter (11.5 kg live weight), longissimus muscle of lambs was sliced, packaged under modified atmosphere (80,20%/O 2:CO 2) and stored in retail conditions. At each sampling point (0, 3, 7, 10, 14 days), microbiological, physicochemical and sensory characteristics were analysed. Vitamin E and GP-5 were found to be effective (p < 0.05) at preventing enterobacteria growth as of day 10. After day 10, vitamin E and grape pomace in the ewe's supplementation reduced metmyoglobin (p < 0.05) lipid oxidation (p < 0.05) and sensory spoilage throughout the storage period. An effect of the grape pomace dosage was observed, with the supplementation at 5% being more effective. Therefore, we can conclude that grape pomace was just as effective as vitamin E in preventing spoilage during retail storage. • Addition VIT-E and grape pomace to ewe diet affects shelf life of suckling lamb meat packaged and stored in retail conditions. • Ewes fed VIT-E and grape pomace delayed myoglobin, lipid oxidation and sensory spoilage of suckling lamb meat during storage. • Grape pomace was as effective as vitamin E in extending the shelf life of lamb meat. • Supplementation of 5% grape pomace in ewe diets was more effective at extending shelf life of suckling lamb meat than 10% [ABSTRACT FROM AUTHOR]

The knowledge of the storage characteristics over the intended shelf-life period is in the interest of the manufacturing companies and it follows from the requirements of consumers, retailers and law regulations. The aim of the study was an attempt to use non-invasive oxygen determination method based on fluorescence quenching to evaluate the shelf-life of rapeseed oil. The subjects of investigation were refined rapeseed oil samples stored at different temperature conditions (20, 40, 50 and 60 °C) under ambient air and modified atmosphere (50 °C). The samples were analyzed periodically for hydroperoxides using the iodometric method and for the oxygen content in the headspace (with the use of OxySense® 325i system). The results show that lipid degradation during storage was accompanied by oxygen loss in the headspace. The relationship between peroxide value and oxygen concentration fitted the polynomial models. The fluorescence quenching method of oxygen determination may be a suitable and rapid tool for non-destructive shelf-life evaluation of edible oils. In packaging with pure nitrogen, oxygen indicators provide valuable information on the correctness of the packaging process. [ABSTRACT FROM AUTHOR]

The objective of the work was to charac-terize the color of the of the goose breast meat packaged in protective atmosphere and stored in the refrigerated conditions. The aim was realized by determination of total heme pigment concentration; relative concentra-tion of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L* (lightness), a* (redness), and b* (yellowness); and sensory evaluation of the surface color. The experimental material was White Koluda goose boneless breast meat with the skin from indus-trial slaughter. The following 2 protective atmospheres were used in the study: vacuum and modified atmo-sphere (MA) consisting of 80% O2 and 20% CO2. The muscles packed in protective atmosphere were exam-ined on d 4, 7, 11, and 14 of storage. A control sample was goose breast meat stored in air and tested after 24 h after slaughter. The total pigment concentration decreased gradually within 14 d of storage for samples packed in 2 types of atmospheres. The increase in rela-tive concentration of metmyoglobin and the decrease in oxymyoglobin relative concentration in total heme pig-ments in the meat stored in MA was noticed. However, in all times of storage, the relative concentration of the 3 samples of myoglobin forms stored in vacuum was unchanged. The color parameters (L*, a*, b*) did not change for 14 d of storage in the muscles packed in vac-uum. One can state a decrease of the value of the color parameter a* as well as an increase of the value of the color parameter b* in the samples packed in MA. From d 11 to 14 of storage, goose meat packed under MA had lower sensory evaluation intensity of color than muscles under vacuum. The obtained data indicated that the surface color of goose breast meat packed in MA (con-sisting of 80% O2, 20% CO2) or vacuum packed was maintained for 11 and 14 d, respectively. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effects of intrinsic factors (origin, physiological age and seasonality) and extrinsic factors (cut-size, blade-sharpness and dipping treatments) on respiration rate () of fresh-cut pineapple chunks. A mathematical model for respiration rate based on exponential decay was developed that showed a gradual decrease in rate with time. The model parameters (R i and R eq, initial respiration rate and equilibrium respiration rate, respectively) were found useful to compare respiration rates for the factors studied. The average values were 8.52±4.68 and 2.64±0.68ml/kgh for R i and R eq, respectively. R i was affected to a greater extent by physiological age and origin than by season. Cut size had a considerable effect on R i and R eq, with larger cut pieces having the lowest R i and R eq of 5.9 and 2.7ml/kgh, respectively. In contrast, smallest cut pieces had highest R i (7ml/kgh) and R eq (3.2ml/kgh). Cutting the fruit with a razor sharp blade versus a blunt blade decreased the R i, while only caused a slight reduction in R eq. The target O2 and CO2 transmission rate required for optimal modified atmosphere packaging were 7300–12,500 and 13,900–23,500ml/m2 dayatm covering variability in respiration rate due to intrinsic and extrinsic factors studied. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to evaluate the effect of different stunning methods (using two different CO2 concentrations and exposure times) and modified atmosphere packaging systems (MA-O2: 70 O2 +30 CO2 vs MA-CO: 69.3% N2 +30% CO2 +0.7% CO) on the meat quality of Manchego Spanish male light lambs (n =50). One electrically stunned control group was used. The type of stunning affected pH value, meat tenderness and water losses (P <0.05) but did not modify most of the colour coordinates or the lipid oxidation level. Furthermore the modified atmosphere with a low CO level (MA-CO) promoted more tender meat with higher oxidative stability than the high-oxygen packed meat (MA-O2). Most likely both the CO2 gas concentration and the exposure time are relevant in the evolution of meat quality from light lambs stunned with different gas stunning systems. In addition, the use of a low CO level to pack lamb meat permits to remove the oxygen from the pack, which improves meat tenderness and the oxidative stability. [Copyright &y& Elsevier]

Abstract: The oxygen concentration in the headspace of a large number of liquid food containers is assessed with non-intrusive diode laser absorption spectroscopy. The results are compared to those given by a traditional intrusive measurement method. The upper portions of the containers are made of translucent but non-transparent plastic materials, through which the laser light is diffusively transmitted. Measurements are performed both on packages with modified atmosphere and with normal air conditions. It is concluded that the novel non-intrusive technique provides oxygen concentrations that generally differ by less than one percentage point from the reference sensor values. [Copyright &y& Elsevier]

Abstract: Yersinia enterocolitica is a psychrotrophic, facultative anaerobic zoonotic bacterium belonging to family Enterobacteriaceae and it can be transmitted from pigs to humans through pork. The growth of bacteria belonging to Enterobacteriaceae and aerobic spoilage bacteria is usually effectively restricted by 20% or more CO2 enriched atmosphere at refrigerated temperatures. In this study, 40 samples of meat strips from pig cheek (musculus masseter) and 40 samples from hind leg (m. semimembranosus) muscles were packaged in modified atmosphere (MA) (30% CO2/70% O2) and stored at 6°C for 12d. Twenty naturally contaminated samples per muscle type were studied on days 1 and 13. Violet red bile glucose (VRBG) and de Man Rogosa Sharpe (MRS) agar plates were used for enumeration of Enterobacteriaceae including Y. enterocolitica and lactic acid bacteria, respectively. During the 12-d storage at 6°C in MA, the mean number of bacteria on pork strips of cheek meat was increasing from 1.6 to 4.5 log cfu/g and from 3.1 to 7.2 log cfu/g on VRBG and MRS agar plates, respectively. Most of the oxidase-negative isolates on VRBG plates, which were isolated from the cheek meat samples after 12-d cold storage in MA, were identified as Y. enterocolitica 4/O:3. The mean number of this pathogen was 4.1 log cfu/g varying between 2.3 and 5.4 log cfu/g. The pH of the cheek meat and leg meat was measured on days 1 and 13, and it remained high (pH>6) in most cheek meat samples during the storage. No Y. enterocolitica 4/O:3 was isolated from meat strips of hind leg. This study shows that cheek meat of slaughter pigs is contaminated with Y. enterocolitica 4/O:3 and that this pathogen can grow well on raw pork packaged in MA at 6°C even in the presence of high number of lactic acid bacteria. [Copyright &y& Elsevier]

Abstract: Modified atmosphere packaging (MAP) is commonly used to preserve the quality of ready-to-eat lettuce by inhibiting oxidative browning and growth of microbial populations. The efficacy of MAP is improved by the initial displacement of air with a gas mixture of a desirable composition (active MAP). The present work focused on the effects of MAP on indigenous microbial populations and the survival of Salmonella enterica on the surface of the lettuce. Chlorine-washed leaves of romaine lettuce were inoculated with S. enterica serotype Typhimurium or not inoculated and packaged in one of the three systems: (a) passive MAP in polyethylene bags; (b) active MAP in the same bags with a gas mixture of 10% O2, 10% CO2, and 80% N2; and (c) control without MAP. Active MAP ensured the more rapid establishment of a steady-state atmosphere and favorable conditions during the transitional period preceding the steady state. The active MAP had an antimicrobial effect on indigenous lettuce microflora, but not on Salmonella and even favored the survival of the pathogen, possibly due to the elimination of its natural antagonists. The effects of the passive MAP were less pronounced. The results obtained draw attention to potential safety risks of ready-to-eat fresh produce kept in active MAP and require further investigation. [Copyright &y& Elsevier]

Abstract: Few studies have elucidated the changes in starch properties during the long storage period, and none have explained the starch properties of bean grains stored under a nitrogen-modified atmosphere at a low-temperature. This study aims to evaluate the changes in pasting, morphological, thermal and crystallinity properties of starch isolated from carioca bean grains stored for 360 days under three different atmospheric conditions: hermetic storage at 5°C, a nitrogen-modified atmosphere at 15°C and a normal atmosphere at 25°C. The starch isolated from grains stored under nitrogen at 15°C did not differ in the solubility and pasting properties. However, they showed lower crystallinity, swelling power and heat that is necessary for gelatinisation compared to starch isolated from grains stored under a normal atmosphere at 25°C. Therefore, the storage under nitrogen-modified atmosphere is an alternative for the preservation of the thermal and crystallinity properties of bean starch. [Copyright &y& Elsevier]

Most current research on Campylobacter has focused on preharvest or processing plant cross-contamination. Little is known about the effect of storage environment on the survival of Campylobacter on raw poultry. We evaluated the effects of modified storage atmosphere and freezing on the survival of naturally occurring Campylobacter on raw poultry. Broiler carcasses (n = 560) were collected as they exited the chiller in 2 commercial processing plants and were sampled for the detection of Campylobacter, Escherichia coli, psychrophiles, and total aerobes at 0 and 14 d of refrigerated (2°C) storage. Gases evaluated were air, 100% O2, 100% CO2, and a standard poultry modified atmosphere packaging mixture (5% O2 + 10% CO2 + 85% N). Freezing was included as a control group. All carcasses were sampled by the whole-carcass rinse method. The rinse fluid was recovered and pooled from 5 individual rinses, and serial dilutions were made for examination of Campylobacter (42°C, 48 h), E. coli (37°C, 24 h), psychrophiles (plate count agar, 4°C, 7 d), and total aerobic bacterial populations (plate count agar, 37°C, 24 h). Campylobacter counts for .all treatments were reduced during the 14-d storage period but the 100% O2 treatment caused a significantly (P < 0.05) greater reduction than the other gas treatments. For the psychrophiles, storage in air resulted in the greatest growth after 14 d, with reduced psychrophilic growth allowed by either O2 or the modified atmosphere packaging mixture (not different from each other). Of the treatments evaluated, CO2 allowed the least growth of psychrophiles. Proliferation of E. coli and aerobes was the greatest when packaged in air after 14 d, whereas CO2 packaging resulted in the least growth. These data suggest that storage under O2 may reduce Campylobacter recovery and slow psychrophile and aerobe recovery following storage. [ABSTRACT FROM AUTHOR]

Abstract: Several treatments were applied in order to delay postharvest degreening in broccoli florets and investigate their effects on genes associated with chlorophyll catabolism. Degradation of chlorophylls is the most evident visual manifestation of broccoli postharvest deterioration, occurring rapidly due to the immature stage in which the material is harvested. Treatments such as storage in modified atmosphere, exposure to hot air, UV-C and white lamps were employed in the current work to induce a delay in degreening and chlorophyll degradation. Expression of genes possibly related to chlorophyll catabolism was analyzed in these samples and discussed. Chlorophyllases, the enzymes traditionally believed to remove the phytol side chain from chlorophyll appear to have a gene expression that was not regulated by postharvest treatments. Pheophytinase, a recently discovered new enzyme in this metabolic pathway, correlated chlorophyll loss accurately in heat, UV-C and white-light treatments, but not in modified atmospheres. Results presented in this work indicate that postharvest treatments that delay chlorophyll degradation have a higher effect on the expression of pheophytinase rather than on chlorophyllase genes. [Copyright &y& Elsevier]

Abstract: Characterization of psychrotrophic lactic acid bacteria (LAB) and Brochothrix thermosphacta communities is needed to understand the microbial ecology of spoilage of modified atmosphere-packed (MAP) meats. To overcome the limitations of the currently used methods for the characterization of psychrotrophic bacterial communities in meat, we developed a culture-independent, 16S rRNA gene-targeted terminal restriction fragment length polymorphism (T-RFLP) method. An identification library consisting of 100 Gram-positive and 30 Gram-negative meat-associated bacterial strains was set up to identify the terminal restriction fragments derived from the communities. The taxonomic resolution level of the T-RFLP method was in between genus and species within the investigated LAB strains and within family and genus within the investigated Gram-negative strains. The established library was applied to identify the members of bacterial communities in MAP minced meat at the end of the shelf life. The T-RFLP results and plate counts on Man-Rogosa-Sharpe, Violet Red Bile Glucose, and Streptomycin sulfate thallium acetate actidione agars indicated that LAB and B. thermosphacta predominated in meat. The bacterial taxa associated with the T-RFLP results were compared to those identified among plate-grown LAB isolates by numerical ribopattern analysis. Both methods agreed that Leuconostoc spp. and Carnobacterium spp. prevailed in the LAB community in minced meat followed by Lactobacillus algidus, Lactococcus spp. and Weissella spp. Colony identification revealed that Leuconostoc gasicomitatum, L. gelidum, Carnobacterium divergens and C. maltaromaticum were the predominant LAB species. The T-RFLP results were shown to correlate with viable counts of Leuconostoc spp. and B. thermosphacta. The T-RFLP method was found to be a useful tool enabling rapid and high-throughput characterization of psychrotrophic bacteria prevailing in MAP meat. [ABSTRACT FROM AUTHOR]

Abstract: Modified atmosphere packaging (MAP) has the potential to extend the shelf-life of fresh-cut lettuce mainly by limiting the oxidation processes. However, exposure to light conditions has been described as causing browning and quality loss. The influence of O2 partial pressures (pO 2) and light exposure during storage on the shelf-life of fresh-cut Romaine lettuce was studied. Fresh-cut lettuce was exposed daily during storage to different light conditions: light (24h), darkness (24h) and photoperiod (12h light+12h darkness). Changes in respiration rate, headspace gas composition, sensory quality, colour, electrolyte leakage, stomatal opening, water loss, texture and compositional constituents related to browning such as vitamin C and individual and total phenolic compounds were evaluated. Different weight samples (75–275g), packaged with an initial pO 2 of 0.5–2.0kPa balanced with N2, reached pO 2 from 0.1 to 1.5 at the steady-state. Atmospheres with low pO 2 (0.2–0.5) at the steady-state preserved lettuce quality by the control of browning and the prevention of off-odours and off-flavours. Light exposure during storage positively influenced the number of open stomata (74% in light vs 24% in darkness) which contributed slightly to weight loss. Consumption of O2 in samples exposed to light differed significantly from those stored in photoperiod or darkness (10.6±7.0, 18.3±3.5 and 25.8±8.6nmolO2 kg−1 s−1, respectively). Packages exposed to light showed higher pO 2 compared with packages stored in darkness while those exposed to photoperiod had intermediate values. Moreover, location of the packages in the shelves affected package headspace gas composition and thus, packages near the front of the shelves showed higher pO 2 than those at the back. The different light conditions did not influence the content of vitamin C or the individual and total phenolic compounds. This study shows that under light conditions respiration activity was compensated by photosynthesis resulting in a higher pO 2. Thus, browning of fresh-cut Romaine lettuce can be promoted by light exposure during storage as it increases headspace pO 2. [Copyright &y& Elsevier]

Abstract: Oil rose flowers were stored at 0°C in four different packaging materials [plastic box+stretch film (PB+SF), Xtend®, Smartbag® and polyethylene (PE)] for 60 days. During storage, weight loss, O2 and CO2 concentrations in the packages, petal color and sensorial attributes were investigated besides essential oil content and composition. Storage duration and packages had significant (p <0.01) effects on weight loss. At the end of storage, the lowest weight loss was in PE package (1.696%) whereas the highest weight loss was in Xtend® (10.081%). The essential oil content was significantly (p <0.01) affected by storage duration and packages. In addition, the essential oil contents obtained from all packages for a storage period of 10 days and the essential oil contents obtained from unstored (control) petals were included in the same group. At the end of storage, the essential oil contents decreased by 91.3, 57.7, 80.0 and 64.3% in PB+SF, Xtend®, Smartbag® and PE packages, respectively as compared to control. In addition, storage duration and package types significantly (p <0.01) affected petal color, O2 and CO2 concentrations in the packages and sensorial scores. The concentration of citronellol, a main component of rose oil, increased in all packages during storage of 10 days in comparison to the control group while it varied in other storage durations and package types. However, nerol and geraniol were lower than the control group during storage while concentrations of nonadecane, heneicosane and eicosane were higher. In conclusion, loss of oil yield and quality, due to various reasons and particularly due to fermentation in oil rose from the harvest of petals to their distillation, can be minimized with storage of petals in all package types for up to 10 days. [ABSTRACT FROM AUTHOR]

Abstract: The effects of using a reduced-oxygen atmosphere (ROA) ([O2]<4.5%) for dry-cured ham processing on sensory traits and on the reduction of the development of “coquera” (development of musty off-odours due to the formation of hollows or cracks between the muscles located around the coxofemoral joint and the subsequent growth of microorganisms and mites in this area) were investigated at two environmental relative humidity conditions in two independent experiments. In Experiment 1, six hams were processed in ROA and six in air for 275days; in Experiment 2, where a lower RH than in Experiment 1 was applied, six hams were processed in ROA for 289days, six for 214days in air+75d in ROA, and six in air for 289days. Sensory analyses were performed on the final product. The use of ROA increased brightness, external redness, white film, pastiness, bitterness and raw meat, metallic and pigsty flavours and reduced musty odour, external matured odour, sweetness, aged and matured flavours and overall liking, these changes being more important when ROA was used during the whole process. The drying of hams in ROA is considered inadequate to produce traditional dry-cured hams because it has negative effects on some sensory properties. [Copyright &y& Elsevier]

Abstract: Forty-nine Manchega breed male suckling lambs were used in this experiment. The effect of CO2 concentration and exposure time at stunning [80% CO2 for 90s (G1); 90% CO2 for 90s (G2); 90% CO2 for 60s (G3); 80% CO2 for 60s (G4)] plus an electrically stunned control group (G5) was assessed for pH, colour (L ∗, a ∗, b ∗, C ∗ and h ∗), water holding capacity (WHC), drip loss (DL), cooking loss (CL) and shear force (SF) in samples packed under two different types of modified atmospheres (MA: MA A: 70%O2 +30%CO2; MA B: 69.3%N2 +30%CO2 +0.7%CO) at 7, 14 and 21d post-packaging. The lowest pH was found in G4 and in G5. The highest WHC and the lowest CL were found in G2 and G3 groups (P <0.05). Modified atmospheres did not affect on pH, WHC, CL and DL, although a significant effect (P <0.001) on colour was found at all the analysis times. Both the type of stunning and the modified atmosphere affected SF values. [Copyright &y& Elsevier]

Abstract: The effects of two packaging methods on the spoilage of a cook-chill pork-based dish kept under refrigeration were studied. Raw pork cuts and pre-cooked tomato sauce were packed under vacuum “sous vide” in polyamide–polypropylene pouches (SV) or into translucent polypropylene trays under modified atmosphere (80% N2 +20% CO2) and sealed with a top film (PT). Samples were cooked inside the pack at an oven temperature/time of 70°C/7h, chilled at 3°C and stored at 2°C for up to 90days. Microbial (psychrotrophs, lactic-acid bacteria, Enterobacteriaceae, moulds and yeasts), physical–chemical (pH, water activity and total acidity) and sensory (colour, odour, flavour, texture and acceptance) parameters were determined. Heat penetration was faster in SV (2°C/min) than in PT (1°C/min) (core temperature). Both packaging methods were equally effective in protecting against microbial spoilage for 90day at 2°C. Minor counts were only detected for lactic-acid bacteria and anaerobic psychrotrophs in SV. No Enterobacteriaceae growth was found. Slight differences between SV and PT in pH and total acidity were observed. SV and PT had similar effects on the sensory preservation of the dishes. A gradual loss of acceptance of the cooked pork and tomato sauce was observed. Rancid flavour in PT and warmed-over-flavour in SV were noted in the final stages of storage. According to acceptance scores, the shelf-life of both SV and PT was 56days at 2°C. Both packaging methods can be used to manufacture sous vide meat-based dishes subsequently stored under refrigeration for catering use. [Copyright &y& Elsevier]