Effect of chitosan coating and vacuum packaging on the quality of refrigerated grilled pork

The effects of chitosan coating and vacuum packaging on the quality and shelf‐life of retail packaged grilled pork in a PVDC/nylon pouch during refrigerated storage at 2 ± 1°C were investigated. Grilled pork without chitosan coating and packaged in 100% air was used as the control sample. Firmness, pH, colour, peroxide values, microbial population and shelf‐life (as determined by sensory characteristics) of the samples were determined during the storage. The results showed that colour, peroxide values and microbial population coincided with sensory characteristics. The delayed growth of microbes in vacuum packaging can be attributed to inhibition by low levels of O₂. Chitosan coating was shown to minimize oxidation, as reflected by the peroxide values, colour changes and microbial counts of the samples. Vacuum‐packaged chitosan‐coated grilled pork showed negligible microbial growth and was found to be organoleptically acceptable throughout the storage period. Chitosan coating along with vacuum packaging provided a type of active packaging to maintain quality and extend the shelf‐life of grilled pork. Copyright © 2006 John Wiley & Sons, Ltd.     

Sorption Phenomena in Packaged Foods: Factors Affecting Sorption Processes in Package–Product Systems

Sorption process can readily occur from many foods. The sorption behaviours result in loss of food quality and shelf life of the packaged foods by altering the aroma compound profile. Although the intensity of the aroma of a packaged foodstuff depends on the vapour pressure, the interaction of the volatile organic moieties with other food constituents and the aroma barrier characteristics of the package, the nature of the aroma is also imperative in determining the extent of sorption. Sorption properties are largely determined by packaging characteristics, flavour molecules properties, food matrix composition and environmental conditions. The chemical composition, chain stiffness, morphology, polarity and crystallinity of the polymer influence flavour absorption as much as the chemical composition, concentration and polarity of the flavour compounds, as well as the presence of other chemical constituents. External factors such as duration of storage, relative humidity, temperature and the presence of other food components can also affect the solubility of aroma compounds in packaged foods. Factors relating to both chemical and physical structure of flavour, food and packaging influence the degree of sorption and also the sorption pattern. Sorption from the packaged foods is of major concern in the selection and use of plastic packaging materials for food packaging. The present review highlights some of the major factors influencing the sorption process. The scientific principles related to sorption are reviewed and distinguished. Copyright © 2011 John Wiley & Sons, Ltd.     

Evaluation of the Effectiveness of a New Antimicrobial Active Packaging for Fresh Atlantic Salmon (Salmo Salar L.) Shelf Life

Nowadays, consumers demand for fresh, high‐quality seafood products continues to climb, especially in affluent, developed nations. At the same time, there is increasing attention regarding improved utilization of seafood for human consumption; Atlantic salmon is the main species in Chile aquaculture, and most of the salmon are exported as fresh fish to USA. It is well documented that low storage temperature inhibit bacterial growth and biochemical degradation, thus facilitating prolonged shelf life. Partly freezing the outer fillet layer from ?0.5°C to ?2.0°C (superchilling) has proven to be more efficient in inhibiting biochemical changes and bacterial spoilage compared with traditional chilling. Nevertheless, antimicrobial active packaging offers the possibility to increase product shelf life through the reduction of the microbiological damage of the product during its transportation, and thus increasing consumer safety and health. The main objective of this study was to compare the effects of an active antimicrobial packaging on microbiological growth, sensory attributes and instrumental quality measurements of raw Atlantic salmon (Salmo salar) fillets. Flexible plastic films containing Thymol as antimicrobial agent were used for salmon packaging. Salmon were stored at 2°C, 4°C and 8°C. Analyses of aerobic mesophilic bacteria and psicrophilic bacteria count were carried out at 1, 3, 8, 11, 15 and 18 days. L*a*b* colour evolution, overall sensorial properties and chemical evolution were studied. Application of active antimicrobial packaging for fillet salmon reduced the microbial count for least 18 days at 2°C. No modification of the sensorial properties was detected by the sensorial panel, indicating that the antimicrobial compound used in the present study, thymol, is compatible with salmon packaging. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of hinokitiol impregnated sheets on shelf life and quality of “KEK‐1” tomatoes during storage

Hinokitiol (β‐thujaplicin, volatile oil extracted from the wood of Hiba arborvitae [Thujopsis dolabrata var. hondae], cypress family) is a natural preservative, antimicrobial, and chelating agent, used to prevent decay and extend the shelf life of fruits and vegetables. In the present study, we used nonwoven rayon sheets impregnated with hinokitiol to conduct packaging studies. Mature green tomatoes var. “KEK‐1” were packaged under three packaging conditions, ie, modified atmosphere packaging (MAP), MAP + hinokitiol (MH), and perforated film package (as control), and their quality attributes were compared during storage. The packaging materials used were low‐density polyethylene (LDPE) film (40 μm) and fresh sheets of nonwoven rayon impregnated with hinokitiol. O₂ in the MAP packaged tomatoes were retained throughout the storage period (3% to 5% O₂). Results showed that MH had slightly improved quality attributes throughout the storage period when compared with MAP alone. Expression levels of LeACS, LeADH, and LeTBG4 genes were higher in 5 and 9 days of control when compared with MAP and MH. “KEK‐1” tomatoes had longer shelf life under MAP and MH packaging and maintained the quality at 15°C. Hence, the effect of the MAP with bioactive packaging treatments could be effective in the future application for the extension of shelf life and quality of fruits and vegetables.     

Effect of modified atmosphere packaging and superchilled storage on the shelf‐life of farmed ready‐to‐cook spotted wolf‐fish (Anarhichas minor)

Modified atmosphere packaging (MAP) combined with superchilling (?1°C) was evaluated as a mild preservation method for farmed spotted wolf‐fish (Anarhichas minor). Portions were packaged in air and in CO2:N2 (60%:40%) atmosphere with a gas:product ratio of approximately 1, at superchilled (?1.0°C ± 0.2°C) or chilled (+4.0°C ± 0.2°C) temperatures. A reduced bacterial growth (p < 0.001), measured as aerobic plate counts (APC) and psychrotrophic bacteria, was observed in modified atmosphere (MA) packaged wolf‐fish at both ?1°C and +4°C, compared to portions in air. MA‐packaged wolf‐fish had improved odour and flavour scores (p < 0.05), but also a higher drip loss than fish stored in air. A shelf‐life of 15 days was obtained at ?1°C for MA‐packaged fish compared to 8–10 days in air, and at 4°C the shelf‐life was 13 days in MA and 6–8 days in air. Copyright © 2006 John Wiley & Sons, Ltd.     

Combined effect of chill storage and modified atmosphere packaging on mussels (Mytilus galloprovincialis) preservation

Changes in biochemical indices, microbial growth, headspace and sensory quality of mussels which had been packaged in two modified atmospheres [Modified atmosphere packaging (MAP) 1: 60% CO₂/20% N₂/20% O₂ and MAP 2: 60% CO₂/40% N₂] and under vacuum (VP) were studied for 14 days. The results showed better quality retention and greater shelf life of mussels packaged under MAP 1 as compared to MAP 2 and VP samples. Increase in total volatile basic nitrogen followed the order: MAP 1 < MAP 2, VP < air (control) samples while increase in trimethylamine nitrogen followed the order: MAP 1 < air < MAP 2 < VP. The 2‐thiobarbituric acid (TBA) values of MAP 1 and air samples were significantly higher (p < 0.05) than the TBA values of VP and MAP 2 samples. MAP 1 showed a greater (p < 0.05) inhibition effect on total viable count of mussel samples than all other packaging conditions. Based primarily on odour scores, the MAP 1 samples remained acceptable up to ca. 10–11 days, the MAP 2 and VP up to ca. 7–8 days while the air‐packaged samples up to ca. 5–6 days of storage. Copyright © 2007 John Wiley & Sons, Ltd.     

The Effect of Active Packaging on Minimizing Food Losses: Life Cycle Assessment (LCA) of Essential Oil Component‐enabled Packaging for Fresh Beef

Packaging plays an important role in ensuring food safety and quality, and the development of active packaging, especially antimicrobial packaging, enables actively inhibiting/killing the microorganisms causing food spoilage and thus extending the product's shelf life. A survey of the publications revealed that generally 50% shelf life extension is possible. The goal of this study is to assess the overall environmental performance of the food and packaging system considering the effect of food loss reduction by using active packaging. A comparative life cycle assessment has been carried out, focusing on a case study: essential oil component‐enabled packaging for fresh beef. Different scenarios were set up to contrast the situations of food using conventional packaging (current situation) and food using novel active packaging (containing active coating). Additionally, a sensitivity analysis has been integrated, aiming to identify the breakeven point of the balance. In the scenarios using the best‐performance active packaging, it was shown that a breakeven point can be achieved across the four impact categories evaluated, including global warming, fossil energy demand, acidification potential and eutrophication potential. It is expected that the obtained results would serve as guidelines for active packaging development striving for a positive eco‐profile of the food and packaging system. Copyright © 2015 John Wiley & Sons, Ltd.     

Effect of vacuum packaging and sodium acetate on the shelf life of seer fish during iced storage

This paper gives in detail the changes occurring in vacuum‐packed seer fish ( Scomberomorus guttatus ) during ice storage. Seer fish steaks were packed in laminated pouches to study the effect of vacuum packaging with and without sodium acetate treatment, in comparison with air‐packed samples. All these samples were stored in ice and were subjected to biochemical, microbiological and sensory evaluation at regular intervals. The shelf life of seer fish steaks packed without vacuum and treatment was 21 days, whereas sodium acetate‐treated steaks without vacuum and untreated vacuum‐packed steaks had a shelf life of 31 days. Steaks with sodium acetate treatment and vacuum packing had a shelf life of 34 days. Based on the results, it is observed that a combination of vacuum packaging and treatment with sodium acetate significantly increases the storage life of seer fish in ice. Copyright © 2002 John Wiley & Sons, Ltd.     

Active Packaging Films from Ethylene Vinyl Alcohol Copolymer and Clove Essential Oil as Shelf Life Extenders for Grass Carp Slice

Active packaging provides a way to prevent the food putrefaction effectively . Various studies provide information on the actual preservation effect of active packaging or the migration of active agents from active films into various food stimulants separately. However, there is little related data available regarding the combined analysis of release and preservation effect. In this work, we examined the properties of active food packaging films successfully produced by extrusion of ethylene vinyl alcohol copolymer (EVOH) films with clove essential oil (C). The characterization of mechanical, thermal and barrier properties of the packaging polymers film showed that the addition of clove essential oil did not decrease their properties and C as plasticizer improved process fluidity of EVOH resin. The release of C from film to various food stimulants was measured by using HPLC, and Fickian diffusion models were used to fit the data with appropriate equation. The effects of E/C (ethylene vinyl alcohol copolymer/clove essential oil) films on quality assessment of Grass Carp slice based on sensory analysis and biochemical indices during refrigerated storage (4 ± 1°C) were examined over the period of 10 days. Total volatile basic nitrogen (TVB‐N), total viable counts, pH, TBA, water holding capacity (WHC) and texture properties were evaluated. The results indicated that the active film containing 3% clove essential oil had different release parameters in four food stimulants and it could effectively maintain the fish freshness and extend the shelf life to 7–8 days during cold storage compared with control group, which was only 4 days. Copyright © 2016 John Wiley & Sons, Ltd.     

Shelf life extension of fresh asparagus using modified atmosphere packaging and vacuum skin packaging in microwavable tray systems

Asparagus (Asparagus officinalis L.) is one of the most popular vegetables because it contains a wealth of fiber and several essential nutrients. It is a very perishable commodity due to its very high respiration rate. To maintain product quality and to satisfy consumer demand as a convenient food, modified atmosphere packaging (MAP), vacuum skin packaging (VSP), and microwaveable containers were used to extend the shelf life of fresh-cut asparagus as a ready-to-eat food product. The objective of this study was to determine the shelf life of fresh-cut asparagus packed in MAP and VSP microwaveable tray systems at commercial storage conditions, 4°C, 80% RH. Weight loss, moisture content, O₂/CO₂ concentration in the package headspace, product pH, microbial growth, and sensory evaluation were used to determine the product quality and shelf life. Moreover, the preference of product appearance and the quality of the cooked asparagus in both microwaveable tray systems at different cooking times and microwave power levels was also sensorially evaluated. During storage for 21 days, there was no significant difference (p > 0.05) in weight loss, moisture content, and pH. Sanitation and packaging techniques also helped to retard the microbial growth. Both techniques, combined with refrigeration, help to maintain the freshness and product shelf life up to 21 days for MAP and 18 days for VSP. On the basis of hedonic scale results, consumers preferred the appearance of both packaging types. Both microwavable tray systems, thus, can help to prolong the shelf life of fresh-cut asparagus and can be eaten directly from the package.     

Advancing controlled release packaging through smart blending

Researchers from Rutgers University and Clemson University have collaborated to develop a concept of using smart blending to generate functional packaging films for the controlled release of active compounds such as antimicrobials, antioxidants and flavour compounds to extend the shelf‐life of food. In this paper, literature results are reviewed to justify the significance of controlled release packaging (CRP) and the research gaps for further development are identified. A major research gap is the lack of packaging materials that can provide the release of active compounds at rates suitable for a wide range of food packaging applications. Smart blending is a promising technology for bridging this research gap. To fully realize the potentials of smart blending, a systematic approach for developing CRP using smart blending is also presented. Copyright © 2005 John Wiley & Sons, Ltd.     

Comparative Life Cycle Assessment of Packaging Systems for Extended Shelf Life Milk

The aim of this study is to carry out a comparative analysis of the environmental impact of different packaging systems used for extended shelf life milk. The analysis, carried out exploiting the life cycle assessment approach, takes into account the packaging manufacturing process, the food packaging process, the transport phases and the end‐of‐life management of the different packaging systems. The packaging end‐of‐life is modelled by considering three possible options, such as recycling, thermo‐valorization with energy recovery and landfill. One litre of extended shelf life milk is used as the reference unit, while multilayer cartons, polyethylene terephthalate bottles labelled with shrink sleeve film and high‐density polyethylene bottles are analysed as the packaging types. The key characteristics of each component of the three packaging systems were either provided by packaging manufacturers or derived from data available in literature. The evaluation of the end‐of‐life impact was performed considering the Italian scenario, exploiting, in particular, the data provided by specific Italian consortia. Other data for the inventory analysis phase were extrapolated from the SimaPro databases (e.g. Ecoinvent or Plastic Europe Database). Cumulative energy demand and CML2001 were adopted as the impact assessment methods. The results obtained show that the multilayer carton system is the less environmentally impactful option for almost all the considered impact categories and that its environmental impacts are, on average, more than 12% lower than high‐density polyethylene system and more than 34% lower than polyethylene terephthalate with shrink sleeve label. Copyright © 2016 John Wiley & Sons, Ltd.     

An overview of smart packaging technologies for monitoring safety and quality of meat and meat products

The food packaging sector has experienced much development since its inception. In the past few decades, innovations in packaging sector have led to the development of smart packaging (SP) systems that carve a niche in a highly competitive food industry. SP systems have great potential for improving the shelf‐life, and safety of food products apart from their basic roles of protecting the products against unwanted biological, chemical, and physical damage and keeping them clean. Indicators and sensors, SP components, are used for real‐time monitoring of meat quality and subsequently inform the retailers and consumers about the freshness, microbiological, temperature, and shelf life status of the products. Barcodes and radio‐frequency identification tags are employed in meat packaging for real‐time information about the authenticity, and traceability of the products in the supply chain. Recently, innovations in SP technologies resulted in fast, sensitive, and effective detection, sensing, and record keeping of freshness, microbiological, and shelf life status of meat and meat products. The SP system shows promise for extensive utilization in the meat industry in response to the consumer appreciation for safe, and quality meat products, as well as their waste reduction notions. This paper gives an updated overview of ongoing scientific research, and recent technological advances that offer the perspectives of developing smart meat packaging systems that are capable of monitoring the physical, microbial, and chemical changes of the package contents from producer to the point of sale and even beyond, and remediating potential adverse reactions.     

A Multi‐functional Biofilm Used as an Active Insert in Modified Atmosphere Packaging for Fresh Produce

We developed a multi‐functional agar‐based biofilm for fresh produce packaging by modulating its CO₂ absorption and water vapour absorption functions. The film was prepared from solutions containing agar as a matrix and a water vapour absorbent, glycerol as a plasticizer, and sodium carbonate (SC) and/or sodium glycinate (SG) as a CO₂ absorbent. The optical, mechanical, and CO₂ and water vapour absorption properties of SC, SG, and SC/SG films were investigated. Multi‐functional films tended to show poor mechanical properties, with a hard texture and an opaque and yellowish colour. The three films had different CO₂ absorption capacities and coefficients, with SC film showing the highest absorption, followed by SC/SG and SG films. The water absorption coefficients were much higher than those of CO₂, with the opposite dependence on the absorbent compound. The multi‐functional benefits of the developed film were shown by using the film for modified atmosphere packaging (MAP) of shiitake mushrooms as an insert label. A tailored MAP design for shiitake mushrooms was produced based on mass transfer mathematical models. The package attached with SC film label was capable of generating the desired internal atmosphere and thus showed the best quality preservation in terms of colour, firmness, flavour score, and bacterial growth after 5‐day storage. A tailored MAP system with our multi‐functional film can provide an optimal modified atmosphere for CO₂‐sensitive fresh commodities, preserve their quality, and extend their shelf life. Copyright © 2015 John Wiley & Sons, Ltd.     

Effect of chitosan‐propolis edible coatings on stability of refrigerated cachama (Piaractus brachypomus) vacuum‐packed fish fillets

The effect of chitosan‐based coatings containing ethanolic extracts of propolis (EEPs) on the quality of chill‐stored, vacuum‐packed fillets of cachama, an emerging aquaculture species of fish native to the Amazon basins, was evaluated. Coatings were prepared by adding propolis to chitosan following two different strategies: (1) incorporation of microencapsulated EEP and (2) direct incorporation of EEP. Fillets were dip‐coated, vacuum‐packed in medium‐oxygen barrier bags, stored at 4°C, and their quality was evaluated during 20 days, by monitoring lipid oxidation indexes, physicochemical parameters, microbiological quality indicators, texture profile, and sensory acceptance. Chitosan‐EEP coatings significantly increased the time stability of physicochemical, microbiological, and sensory quality indicators of the fish meat compared with control treatments (uncoated vacuum‐packed fillets). In particular, the secondary lipid oxidation of the coated muscles was 12% to 15% lower compared with uncoated samples after 12 days; pH and total volatile base nitrogen (TVB‐N) presented a slower increase in the coated samples; and a greater inhibition of coliforms was observed between days 8 and 16. The chitosan‐EEP coatings had a positive effect in both texture stability and sensory acceptance of the products during storage. Moreover, chitosan coatings with encapsulated EEP had better impact on the evaluated sensory quality parameters. The results indicate that the combination of the barrier properties of chitosan with the bioactive properties of propolis compounds against oxidative free radicals and microbiological deterioration allowed for the edible coatings to extend the shelf life of this aquaculture product with respect to conventionally vacuum‐packed fillets.     

The Applications of ‘active packaging and chlorine dioxide’ for extended shelf life of fresh strawberries

Fresh strawberries are highly perishable because of their high respiration rates. Three alternative packaging approaches were investigated to maintain the high quality and to extend the shelf life of strawberries. These were active packaging using chlorine dioxide (ClO₂) and ethylene‐moisture sachets. The quality properties of four groups of samples were measured over 3 weeks at 4°C. The groups were: control, active packaging without ClO₂ treatment, active packaging with low‐dose (5 ppm) ClO₂ treatment and active packaging with high‐dose (10 ppm) ClO₂ treatment. Measured properties were weight loss, gas concentration, pH, titratable acidity (TA), soluble solids content, texture profile and colour. Active packaging with low‐dose (5 ppm) ClO₂ treatment was found to be the most effective for TA retention and for maintaining (L) brightness values. The control group showed the largest total soluble solids reduction from 7.60 to 6.57. Active packaging without ClO₂ treatment showed the lowest weight loss (0.33%), while the control group showed the highest (1.86%) at the end of the storage. Active packaging with high‐dose ClO₂ treatment showed the highest preference value in global appearance, colour and firmness properties. The low‐ and high‐dose active packaging groups had greater firmness, gumminess and chewiness than that of all other treatments. The results from this study showed that active packaging treatment with ClO₂ and the ethylene‐moisture sachets had a beneficial effect on the quality of strawberries and could be used commercially. Copyright © 2010 John Wiley & Sons, Ltd.     

Use of Sodium Lactate and Modified Atmosphere Packaging for Extending the Shelf Life of Ready‐to‐Cook Fresh Meal

In this work, the combined effects of sodium lactate and modified atmosphere packaging (MAP) in extending the shelf life of a ready‐to‐cook fresh skewer, made up of raw pork chops and semi‐dried vegetable mix (i.e. zucchini, peppers and tomatoes), were investigated. In the first experimental step, a sodium lactate solution was used to dip pork chops at three different concentrations: 20, 40 and 60% w/w. The second part of the work was focused on the use of MAP. In particular, the following MAPs were tested: MA1 (50%O₂/30%CO₂/20%N₂), MA2 (70%O₂/30%CO₂), MA3 (30%O₂/70%CO₂) and MA4 (30%O₂/30%CO₂/40%N₂). Finally, the optimal concentration of sodium lactate and the best gas composition were combined. The samples were stored at 4 °C; their microbial and sensory qualities were monitored along the entire observation period. The results indicate that the shelf life of the investigated ready‐to‐cook meal can be extended by approximately 83%, if compared with the control skewer packaged in air. The best preservation strategy is the combination of dipping of meat pieces in 40% sodium lactate solution and packaging under MA1. Copyright © 2014 John Wiley & Sons, Ltd.     

Effectiveness of modified atmosphere packaging in preserving a prepared ready‐to‐eat food

The effectiveness of modified atmosphere packaging (MAP) was evaluated for a combination prepared food (Korean braised green peppers with dry anchovies). From a preliminary storage test of the ready‐to‐eat dish at 10°C, the aerobic bacterial count on the green peppers was selected as a primary quality index. The effect of MAP with different CO₂ concentrations on the product quality at 10°C was also studied. MAP with a CO₂ concentration of ≥30% extended the lag time and/or reduced the growth rate of bacteria. Finally, the effect of different storage temperatures (5, 10, 15 or 20°C) on the shelf life of the product was investigated. Mathematical modelling of bacterial growth curves under stretch‐wrap air packaging and MAP with 60% CO₂/40% N₂ showed that MAP increased the hypothetical minimum temperature in the square root model that describes the temperature dependence of the lag time and growth rate. MAP conditions of 60% CO₂/40% N₂ extended the shelf life at 10°C by 130% (to 18.4 days) relative to that achieved with stretch‐wrap air packaging (7.9 days) based on the time taken to reach the quality limit of an aerobic bacterial count of 10⁵ CFU/g. The relative extension of shelf life achieved with MAP was greater at lower temperatures. Copyright © 2008 John Wiley & Sons, Ltd.     

Effects of PP‐based Nanopackaging on the Overall Quality and Shelf Life of Ready‐to‐eat Salami

A total of 1% nanoclay containing polypropylene (PP)‐nanocomposite and 1% nanoclay plus 5% poly‐beta‐pinene (PβP) containing PP‐active‐nanocomposite materials were produced and tested for packaging of sliced salami. The sliced salami was packaged using both nanofilms and multilayer film of PP/PA/EVOH/PE under vacuum, modified atmosphere packaging under 50% CO₂ and 50% N₂ and air and stored at 4 °C for 90 days. During storage, headspace gas composition; microbial, physical and chemical analyses; and sensory evaluation were performed. The antimicrobial effect of PβP containing nanomaterial was pronounced under vacuum, and no bacterial growth was observed for 75 days. An a* value decreased notably in all applications during storage and preserved best by the multilayered material under vacuum and high CO₂. Thiobarbituric acid reactive substances (TBARS) were 0.63 mg MDA/kg after the processing and gradually increased at all applications during increased storage. TBARS values of all vacuum applications were lower than that of modified atmosphere packaging applications. Rancid taste development was determined by sensory panelists when TBARS values were higher than 0.80 mg MDA/kg on the 90th day. There was no significant moisture loss, and no increase in hardness was determined during the whole storage time. The longest shelf life was 75 days for the sliced salami under vacuum and high CO₂ using the multilayer material. PβP containing nanomaterial provided 50 days of shelf life under vacuum, which is commercially considerable. Copyright © 2017 John Wiley & Sons, Ltd.