Cheese Packaging Research Articles

Evaluation of the potential synergistic antimicrobial effects observed using combinations of nanoparticled and non‐nanoparticled agents on cheese‐derived micro‐organisms

The objective of this study was to determine whether a combination of agents could produce a synergistic antimicrobial effect, by either targeting a greater spectrum of micro‐organisms or reducing the concentration of antimicrobial required to cause inhibition. Five agents (nanoparticled solubilisates – sorbic acid, benzoic acid and rosemary extract, and non‐nanoparticled chitosans – of two different molecular weights) were selected based on promising antimicrobial activity and/or enhanced solubility. Combinations of these agents were examined against cultures derived from cheese. The study found the top‐performing antimicrobials contained chitosan and/or rosemary, individually or in combination. These findings encourage their use as active agents in cheese packaging.

Packaging of cheeses: innovation or constraint? Exemple: Blue veined cheese

Packaging of cheeses: innovation or constraint? Exemple: Blue veined cheese

Estimation of the main compositional features of grated Parmigiano Reggiano cheese by a simple capacitive technique

The non-destructive assessment and control on and off-line of some quality parameters of the grated cheese is a goal of the dairy industries and distributors. The present research is addressed to explore the possibility of estimating the percentage of moisture, proteins, added rind, and the ripening time of this kind of cheese by a capacitive technique supported by basic statistical analysis and artificial neural networks (ANN). An instrumental chain composed by a parallel plate capacitor probe, for housing the cheese in a suitable container, and a LCR meter, were used to measure the capacitance of different product mixtures, in the frequency range from 100Hz to 10kHz. Samples were prepared by mixing cheeses ripened from 8months to 36months and rind percentage from 0% to 50%. The results show that moisture and protein percentages can be estimated in a quite good manner with a linear correlation (R2 up to 0.81) and ANN (R2 up to 0.83). The ripening time is well linearly assessed in the cheese without the addition of rind (R2=0.994) or if the rind percentage is known (R2 from 0.872 to 0.963). The rind percentage is very well linearly estimated if the ripening time is known (R2 from 0.914 to 0.987). Estimation of the rind percentage if the ripening time is unknown appears more difficult (max R2=0.658) because both ripening and addition of rind involve a decrease in capacitance. The frequency at which the capacitance is measured shows only a weak influence in the goodness of the parameters determination. On the whole and as a trend, the correlations improve increasing the frequency.The obtained results, the conformation of the probe and the minimal data treatments mean that this technique can be considered to be applied in the chains of the grated cheese packaging.

Assessment of the antimicrobial activity of potentially active substances (nanoparticled and non‐nanoparticled) against cheese‐derived micro‐organisms

This study evaluated the antimicrobial potential of various naturally occurring substances, for use as active agents in cheese packaging. Sorbic acid and benzoic acid were examined as standard‐sized and nanoparticled solutions. Rosemary, curcumin and ascorbic acid were employed as nanoparticled solutions only, while non‐nanoparticled chitosan, of two molecular weights, were also selected for evaluation. All agents were assessed against micro‐organisms derived from cheese. Chitosan proved to be the most effective, with low molecular weight chitosan performing best. The most antimicrobial nanoparticle was found to be rosemary. Comparison of normal‐ and nanoparticle‐sized organic acid solutions showed little difference in terms of antimicrobial properties.

Evaluation of Different Conditions of Contact for Caprolactam Migration from Multilayer Polyamide Films into Food Simulants

ABSTRACTCaprolactam, the polyamide 6 (PA‐6) monomer, can migrate during food processing. At cooking temperatures, migration is accelerated and plastic components could degrade, giving off low molecular mass compounds, which can migrate into food. In this work, caprolactam migration from multilayer films containing PA‐6 for meat foodstuffs and cheese packaging was performed at contact conditions of 40°C/10 days and 100°C/30 min. The migration into water ranged from 0.89 to 1.22 mg/dm2 and 0.92 to 1.21 mg/dm2, into 3% acetic acid from 1.29 to 1.74 mg/dm2 and 1.13 to 1.62 mg/dm2 and into olive oil from 1.18 to 1.98 mg/dm2 and 0.50 to 0.80 mg/dm2 for films intended for meat foodstuffs for 10 days at 40°C and 30 min at 100°C, respectively. Among PA‐6 films used for cheese, caprolactam migration into water ranged from 0.17 to 0.91 mg/dm2 and 0.74 to 1.04 mg/dm2, into 3% acetic acid from 1.15 to 1.26 mg/dm2 and 1.11 to 1.37 mg/dm2 and into olive oil from 0.23 to 0.83 mg/dm2 and 0.37 to 0.56 mg/dm2 for 10 days at 40°C and 30 min at 100°C, respectively. Caprolactam migration evaluation into water and 3% acetic acid at 100°C/30 min could replace the need to apply the test at 40°C/10 days, since similar results were obtained under both conditions. In the case of PA‐6 for meat foodstuffs, caprolactam migration into olive oil was highly affected by different conditions of contact, showing values two to three times higher at 40°C/10 days than at 100°C/30 min. For cheese films, caprolactam migration into olive oil was higher at 40°C for 10 days. Copyright © 2013 John Wiley & Sons, Ltd.

Preservation of precut white cheese by modified atmosphere packaging

Effects of modified atmosphere packaging (MAP) on storage stability and quality of precut fresh and aged white cheese were investigated. Fresh or aged white cheese was cut into small cubes and packaged in five different atmospheres [0% O2 + 0% CO2 + 100% N2 (MAP1), 10% O2 + 0% CO2 + 90% N2 (MAP2), 0% O2 + 75% CO2 + 25% N2 (MAP3), 10% O2 + 75% CO2 + 15% N2 (MAP4) and aerobic (air)]. Control samples were packaged in brine and vacuum for fresh and aged white cheese, respectively. Changes in gas composition, total plate count, lactococci, lactobacilli, yeast and mould counts, proteolysis, lipolysis, pH, colour, texture and sensory properties were investigated during refrigerated storage. The best packaging treatment for the fresh cheese was MAP3, as it inhibited mould growth and protected the hardness. MAP2 can be recommended for the packaging of the aged cheese, as it decreased lipolysis.

Preparation and characterization of milk protein films and their application for packaging of Cheddar cheese.

Casein and whey protein concentrate (WPC) films, plasticized with glycerol and sorbitol independently, were prepared by casting. The film thickness, water vapour and oxygen permeation and tensile and moisture sorption properties of the films were determined. The tensile strength (TS), tensile strain (TE) and elastic modulus (EM) of the films ranged from 0.71 to 4.58MPa, 19.22 to 66.63% and 2.05 to 6.93MPa, respectively. The film properties were influenced by the type of biopolymer (casein and whey protein concentrate), plasticizer and its concentration. Increasing the plasticizer concentration, increased the film thickness, TE and water vapour permeability (WVP), but decreased the TS and EM. As the concentration of plasticizer increased to the highest level, the film thickness increased from 0.168 to 0.305mm for glycerol-plasticized films and from 0.251 to 0.326mm for sorbitol-plasticized films. The film thickness increased because the amount of plasticizer in the film network increased and the amount of biopolymer remained same. Casein films showed superior tensile properties as compared to WPC films. The WVP of both casein and WPC films lied between 3.87 and 13.97g.mm./(m(2).h.kPa). The moisture sorption isotherms of both films were typical of high-protein material, and were adequately described by the GAB model. The oxygen permeability of casein films was relatively lower than that of WPC films, regardless of the plasticizer used. The sensory data revealed that the organoleptic quality of Cheddar cheese was unaffected by milk-protein film packaging.

Detection of cheese packaging containment failures using reversible optical oxygen sensors

This study investigated the capacity of optical oxygen sensors to nondestructively detect containment packaging failures in commercial vacuum packed cheddar cheese. Unacceptable oxygen levels in packs lead to product deterioration and can significantly reduce shelf life. Vacuum packed cheddar cheese was monitored for oxygen levels over time at 4 °C with optical sensors prefitted to packaging laminates polyethyleneterephthalate/polypropylene. Oxygen levels present in packs immediately after packaging were 3% on average. Further ingress of oxygen into all packs occurred over storage time and levels ranged from 3.6% to 8.2% after 6 days. Information obtained using oxygen sensors led to further assessments and identification of the causes of packaging containment failure.

Preparation of red algae film containing grapefruit seed extract and application for the packaging of cheese and bacon

Red algae (RA) film containing grapefruit seed extract (GSE) was used as a wrapping film for cheese and bacon. RA film containing 1% GSE was prepared to inhibit the growth of pathogenic bacteria such as Escherichia coli O157:H7 and Listeria monocytogenes. Wrapping of cheese and bacon with the film decreased the populations of E. coli O157:H7 and L. monocytogenes. After 15 days of storage, wrapping of cheese with the RA film reduced the populations of E. coli O157:H7 and L. monocytogenes by 1.21 and 0.85 log CFU/g, respectively, compared to control. Bacon wrapped with the RA film also decreased the populations of E. coli O157:H7 and L. monocytogenes by 0.45 and 0.76 log CFU/g, respectively. Wrapping of bacon with the RA film decreased peroxide and thiobarbituric acid values. These results suggest that RA film containing GSE is a useful wrapping material for extending the shelf lives of cheese and bacon.

Light-induced protein and lipid oxidation in low-fat cheeses: whey proteins as antioxidants

Photo-oxidation of cheese products has become an issue due to the fact that packaging of cheeses in transparent materials is very frequently used. The present study aimed to give new aspects of the possible antioxidative activity of whey proteins in photo-oxidation of cheese and the whey proteins were expected to act as scavenger and thereby reduce lipid oxidation. Oxidation was investigated in low-fat model cheese with whey protein isolate (WPI) added and compared to a low-fat control cheese. The cheeses were packed in air or in vacuum, respectively, and stored under light. Accumulations of lipid hydroperoxides, pentanal, hexanal, heptanal, 1-hexanol, dimethyl disulfide and dityrosine were all found to be dependent on the availability of oxygen. The presence of WPI reduced the accumulation of both lipid and protein oxidation products. The consumption of the naturally occurring antioxidant α-tocopherol was not affected by the added WPI. After the seventh day of light-exposed storage during which all riboflavin was decomposed and the concentration of α-tocopherol had found a stable level, the presence of WPI resulted in an extension of the observed lag phase in the accumulation of secondary lipid oxidation products. As WPI reduced the accumulation of protein oxidation products as well, it is suggested that WPI is not a typical radical scavenger.

Light-induced protein and lipid oxidation in cheese: Dependence on fat content and packaging conditions

Photo-oxidation of cheese products has become an issue due to the fact that packaging of cheeses in transparent materials is very frequently used. The present study aimed to investigate the effect of fat content and availability of oxygen on light-induced oxidation in cheese, as we expected that the fat content would affect the oxidation pathways. Two different model cheeses with 5.4% and 18% fat were packed in air and in vacuum, respectively. The contents of protein (dityrosine and dimethyl disulphide (DMDS)) and lipid (lipid hydroperoxides, pentanal, hexanal and heptanal) oxidation products were significantly reduced in vacuum-packed cheeses compared to cheeses packed in air. Protein oxidation correlated to the concentration of lipids in the cheeses, and interactions between the lipid radicals and proteins seemed to be decisive for the generation of dityrosine, whereas the influence of lipid radicals on the generation of the DMDS seemed more ambiguous. The higher levels of dityrosine and DMDS in the cheese with a high fat content indicated that transfer of radicals from the lipids to the proteins occurred. Even though the generation of DMDS was reduced in vacuum-packed cheese when compared to cheese packed in air, DMDS was formed in vacuum-packed cheese.

Polymer films releasing nisin and/or natamycin from polyvinyldichloride lacquer coating: Nisin and natamycin migration, efficiency in cheese packaging

Polyethylene films coated by commercially available polyvinyldichloride (PVdC) as well as nitrocellulose (NC) lacquer with addition of natamycin preparation Delvocid® (16.7% w/w of natamycin in lacquer) were studied at 6 and 23 °C to determine the preservative migration into distilled water. The films released natamycin at maximal level 2.34 ± 0.32 mg/dm 2. The diffusion coefficient of 0.79 × 10 −10 ± 0.29 × 10 −10 cm 2/s and 1.03 × 10 −10 ± 0.17 × 10 −10 cm 2/s was determined for natamycin transport in PVdC lacquer layer at 6 and 23 °C, respectively. For nitrocellulose lacquer the diffusion coefficient of 0.89 × 10 −10 ± 0.16 × 10 −10 cm 2/s was found at 23 °C. The coextruded polyamide/polyethylene film coated with the PVdC lacquer containing both nisin (16.7% w/w of preparation Nisaplin®) and natamycin (see above) provided inhibitory effect against selected indicator microorganisms ( Penicillium expansum, Fusarium culmorum, Lactobacillus helveticus, Listeria ivanovií). This film was unsuitable for the packaging of the surface ripened cheese Olomoucké tvarůžky. On the other hand, it was able to prevent the growth of spoilage microorganisms on the surface of the packaged soft cheese Blaťácké zlato.

Increased presevation of sliced mozzarella cheese by antimibrobial sachet incorporated with allyl isothiocyanate

There is an increasing tendency to add natural antimicrobials of plant origin into food. The objective of this work was to develop a microbial sachet incorporated with allyl isothiocyanate (AIT), a volatile compound of plant origin, and to test its efficiency against growth of yeasts and molds, Staphylococcus sp. and psychrotrophic bacteria on sliced mozzarella cheese. Another objective was to quantify the concentration of AIT in the headspace of cheese packaging. A reduction of 3.6 log cycles was observed in yeasts and molds counts in the mozzarella packed with the antimicrobial sachet over 15-day storage time. The sachet also showed an antibacterial effect on Staphylococcus sp., reducing 2.4 log cycles after 12-day storage. Psychrotrophic bacteria species were the most resistant to the antimicrobial action. The highest concentration of AIT (0.08µg.mL(-1)) inside the active packaging system was observed at the 6(-)day of storage at 12 ºC ± 2 ºC. At the end of the storage time, AIT concentration decreased to only 10% of the initial concentration. Active packaging containing antimicrobial sachet has a potential use for sliced mozzarella, with molds and yeasts being the most sensitive to the antimicrobial effects.

Gas exchange dynamics in modified atmosphere packaging of soft cheese

Modified Atmosphere Packaging (MAP) is a shelf-life extension technique that has been widely applied to horticultural, meat and dairy products. It relies on the interaction between product, packaging material and environment, which determines the gas composition inside the package at steady state. Therefore, MAP design needs to take into consideration O 2 consumption and CO 2 production rates of the product and the mass transfer coefficients for the gas exchange through the packaging material and how they are affected by environmental factors such as storage temperature. In this work, a mathematical model was developed for designing MAP systems for a soft cheese (camembert-type). The model was used to evaluate the effect of perforations on O 2 and CO 2 concentrations of package containing cheese, at constant and varying storage temperatures. The predicted gas composition was compared with those obtained experimentally at 293 and 285 K with packages having different numbers of perforations (1)–(3). Experimental values of gas composition observed at steady state with one perforation were 0.050 and 0.148 (v/v) at 285 K for O 2 and CO 2 respectively, and 0.003 and 0.207 (v/v) at 293 K. Gas composition was found to take values between 0.009–0.058 for O 2 and 0.154–0.200 for CO 2, when the packages with a single perforation were exposed to storage temperature varying between 285 and 293 K during 14 days of storage. The model developed was able to accurately predict the gas exchange dynamics of the package throughout the storage period whether the temperature of storage was constant or not.

A Life Cycle Comparison of Alternative Cheese Packages

AbstractA comparative life cycle assessment (LCA) between three different cheese packages (P1: completely polypropylene (PP), P2: tin and polyethylene (PE), and P3: carton and PE) has been carried out for the production, distribution and waste disposal (100% landfill) phase. A package for 1 kg of cheese was selected as the functional unit. SimaPro7 software (PRèConsultants, The Netherlands) was used for the LCA study. The EcoIndicator 99 method was selected for comparison of the packages. The comparisons show that the total environmental performance of the cheese package types in order from worst to best is P2, P1, and P3. This conclusion was supported by a sensitivity analysis, which was conducted by using different impact assessment methods.

Increased presevation of sliced mozzarella cheese by antimibrobial sachet incorporated with allyl isothiocyanate

There is an increasing tendency to add natural antimicrobials of plant origin into food. The objective of this work was to develop a microbial sachet incorporated with allyl isothiocyanate (AIT), a volatile compound of plant origin, and to test its efficiency against growth of yeasts and molds, Staphylococcus sp. and psychrotrophic bacteria on sliced mozzarella cheese. Another objective was to quantify the concentration of AIT in the headspace of cheese packaging. A reduction of 3.6 log cycles was observed in yeasts and molds counts in the mozzarella packed with the antimicrobial sachet over 15-day storage time. The sachet also showed an antibacterial effect on Staphylococcus sp., reducing 2.4 log cycles after 12-day storage. Psychrotrophic bacteria species were the most resistant to the antimicrobial action. The highest concentration of AIT (0.08µg.mL-1) inside the active packaging system was observed at the 6-day of storage at 12 ºC ± 2 ºC. At the end of the storage time, AIT concentration decreased to only 10% of the initial concentration. Active packaging containing antimicrobial sachet has a potential use for sliced mozzarella, with molds and yeasts being the most sensitive to the antimicrobial effects.

Migração de β-caprolactama de embalagens contendo poliamida 6 para simulante ácido acético 3% e validação do método analítico

The aim of this work was to develop and validate an analytical method to determine e-caprolactam in 3% acetic acid solution and to study its migration from polyamide 6 into food simulant. Gas chromatography was used with e-caprolactam as an analytical standard and 2-azacyclononanone as an internal standard. The linearity was obtained by the concentration range of 1.60 to 640.00 µg.mL-1, with a correlation coefficient of 0.9999. Detection and quantification limits of the method were 0.24 ng and 1.60 ng, respectively. Relative standard deviations obtained for method precision were less than 4.3%, while method accuracy showed recovery between 100 and 106%. The method was able to quantify e-caprolactam in the simulant, showing a wide linearity, good precision and accuracy. For the migration assay, polyamide 6 films were placed in glass vials containing 10 mL of simulant, which were hermetically capped and exposed at 40 °C for 10 days (total immersion). The amount of e-caprolactam that migrated from packaging into the simulant varied from 7.8 to 10.5 and 6.9 to 7.6 mg.Kg -1, for films used as meat products and cheese packaging, respectively.

Behavior of α‐ and β‐cyclodextrin‐encapsulated allyl isothiocyanate as slow‐release additives in polylactide‐co‐polycaprolactone films

AbstractThe natural antibacterial agent allyl isothiocyanate (AITC) encapsulated in either α‐ or β‐cyclodextrin (CD) has previously been evaluated as a slow‐release additive in polylactide‐co‐polycaprolactone (PLA–PCL) films designed for use in cheese packaging. In the research described in this article, thermogravimetric analysis (TGA) and thermogravimetric analysis in tandem with mass spectrometry (TGA–MS) were used to explore the thermal properties of CD‐encapsulated AITC complexes as well as those of PLA–PCL films containing these complexes. To our knowledge, this is the first reported application of the TGA–MS technique to explore the thermal stability of CD‐entrapped AITC and the first study to report differences in thermal stability of AITC in α‐and β‐CD cavities in the solid state. Observed differences in the thermal degradation profile of films containing the CD complexes can be explained if AITC binds more strongly to β‐CD than to α‐CD. This hypothesis has been reinforced by gas chromatography (GC) and high performance liquid chromatography (HPLC) studies, the results of which suggest that a new covalently bound AITC–CD complex may be formed when incorporating the β‐CD complex of AITC in PLA–PCL films but not when incorporating the α‐CD complex of AITC. This finding means that the α‐CD complex of AITC would be preferred in situations where adequate long‐term controlled release of AITC from polymer films is required, as for example in the case of active packaging applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Active Packaging of Cheese with Allyl Isothiocyanate, an Alternative to Modified Atmosphere Packaging

The natural antimicrobial compound allyl isothiocyanate (AITC), found in mustard oil, is effective against cheese-related fungi both on laboratory media and cheese. Penicillium commune, Penicillium roqueforti, and Aspergillus flavus were more sensitive to AITC when it was added just after the spores had completed 100% germination and branching had started on Czapek yeast extract agar than were spores in the dormant phase. The use of 1 AITC label (Wasaouro interior labels, LD30D, 20 by 20 mm) in combination with atmospheric air in the packaging extended the shelf life of Danish Danbo cheese from 4½ to 13 weeks. Two AITC labels extended the shelf life from 4½ to 28 weeks. Both 1 and 2 labels in combination with modified atmosphere packaging extended the shelf life of the cheese from 18 to 28 weeks. This study showed that AITC was absorbed in the cheese, but it was not possible to detect any volatile breakdown products from AITC in the cheese. Cheese stored for up to 12 weeks with an AITC label had an unacceptable mustard flavor. The mustard flavor decreased to an acceptable level between weeks 12 and 28. Cheese stored in atmospheric air had a fresher taste without a CO2 off-flavor than did cheese stored in modified atmosphere packaging. AITC may be a good alternative to modified atmosphere packaging for cheese. The extended shelf life of cheese in the package is very desirable: the cheese can be transported longer distances, and the packaging can be used for the final maturing of the cheese. Furthermore, AITC can address problems such as pinholes and leaking seals in cheese packaging.

Characterization ofl-polylactide andl-polylactide–polycaprolactone co-polymer films for use in cheese-packaging applications

Impact-modified and unmodified l-polylactide and l-polylactide–polycaprolactone co-polymer films were evaluated for their suitability as materials for cheese packaging. The polymers were in some cases compounded with nanoclays as a possible route to enhanced barrier properties and/or with cyclodextrin complexes designed to provide slow release of encapsulated antimicrobials for control of mould growth on packaged cheeses. The materials demonstrated complete biodegradation under controlled composting conditions and the extruded films had acceptable transparency. Moisture uptake by films and a decrease in polymer molecular weight with time of exposure to high humidity were identified as areas of concern, although the polymer stability experiments were undertaken at 25°C and stability at normal cheese storage temperatures (∼4°C) is expected to be better. Nanoclay addition enhanced the thermal stability of the polymer but reduction of oxygen and water vapour permeability to target levels through incorporation of 5% w/w nanoclay was not achieved, possibly in part due to inadequate dispersion of the nanoclays in the chosen polymer matrices. On the positive side, a novel impact-modified polylactide was developed that overcame problems with brittleness in unmodified l-polylactide and l-polylactide–polycaprolactone co-polymer films, and tests indicated that a cyclodextrin-encapsulated antimicrobial (allyl isothiocyanate) incorporated in l-polylactide–polycaprolactone co-polymer films would be effective in controlling fungi on packaged cheeses. Migration of substances from the l-polylactide or l-polylactide–polycaprolactone films into cheese is not expected to be a problem. Copyright © 2005 John Wiley & Sons, Ltd.