This research was aimed to make biolayer coatings enriched with orange peel essential oil (OPEO) on synthetic laminate, oriented poly(ethylene-terephthalate)/polypropylene (PET-O/PP). Coating materials were taken from biobased and renewable waste sources, and the developed formulation was targeted for food packaging. The developed materials were characterized for their barrier (O2, CO2, and water vapour), optical (colour, opacity), surface (inventory of peaks by FTIR), and antimicrobial activity. Furthermore, the overall migration from a base layer (PET-O/PP) in an acetic acid (3% HAc) and ethanol aqueous solution (20% EtOH) were measured. The antimicrobial activity of chitosan (Chi)-coated films was assessed against Escherichia coli. Permeation of the uncoated samples (base layer, PET-O/PP) increased with the temperature increase (from 20 °C to 40 °C and 60 °C). Films with Chi-coatings were a better barrier to gases than the control (PET-O/PP) measured at 20 °C. The addition of 1% (w/v) OPEO to the Chi-coating layer showed a permeance decrease of 67% for CO2 and 48% for O2. The overall migrations from PET-O/PP in 3% HAc and 20% EtOH were 1.8 and 2.3 mg/dm2, respectively. Analysis of spectral bands did not indicate any surface structural changes after exposure to food simulants. Water vapour transmission rate values were increased for Chi-coated samples compared to the control. The total colour difference showed a slight colour change for all coated samples (ΔE > 2). No significant changes in light transmission at 600 nm for samples containing 1% and 2% OLEO were observed. The addition of 4% (w/v) OPEO was not enough to obtain a bacteriostatic effect, so future research is needed.
In this research, the porous polymer structures (IPN) were made from natural isoprene rubber (NR) and poly(methyl methacrylate) (PMMA). The effects of molecular weight and crosslink density of polyisoprene on the morphology and miscibility with PMMA were determined. Sequential semi-IPNs were prepared. Viscoelastic, thermal and mechanical properties of semi-IPN were studied. The results showed that the key factor influencing the miscibility in semi-IPN was the crosslinking density of the natural rubber. The degree of compatibility was increased by doubling the crosslinking level. The degree of miscibility at two different compositions was compared by simulations of the electron spin resonance spectra. Compatibility of semi-IPNs was found to be more efficient when the PMMA content was less than 40 wt.%. A nanometer-sized morphology was obtained for a NR/PMMA ratio of 50/50. Highly crosslinked elastic semi-IPN followed the storage modulus of PMMA after the glass transition as a result of certain degree of phase mixing and interlocked structure. It was shown that the morphology of the porous polymer network could be easily controlled by the proper choice of concentration and composition of crosslinking agent. A dual phase morphology resulted from the higher concentration and the lower crosslinking level. This was used for developing porous structures from the elastic semi-IPN. The mechanical performance was correlated with morphology, and the thermal stability was comparable with respect to pure NR. Investigated materials might be interesting for use as potential carriers of bioactive molecules aimed for innovative applications such as in food packaging.
BACKGROUND: Poly(lactic acid) (PLA) has limited uses for moist and acidic foods due to its barrier properties, which are fairly poor, and its sensitivity to moisture. RESULTS: Deposition of thin coatings based on natural biopolymers (gelatin) incorporating bioactive agents has allowed the development of active packaging materials while maintaining their biodegradability and their food contact material ability. Gelatin coatings containing two phenolic acids (tannic and gallic) have been tested. These coated PLA films displayed a reduction of the moisture permeability and a slight modification of the thermal properties of PLA. The antioxidant properties of the films and their release kinetics in a simulant medium have been studied and modelled. CONCLUSIONS: Incorporation of phenolic acids induced interactions with the gelatin that modified the structure of the network and positively affected the retention, diffusivity, and transfer rate of the bioactive compounds when coated PLA films were in contact with the liquid simulant. © 2022 Society of Chemical Industry.
Antioxidants , Polyphenols , Antioxidants/chemistry , Gelatin/chemistry , Food Packaging , Polyesters/chemistry
In the last decade both scientific and industrial community focuses on food with the highest nutritional and organoleptic quality, together with appropriate safety. Accordingly, strong efforts have been made in finding appropriate emerging technologies for food processing and packaging. Parallel to this, an enormous effort is also made to decrease the negative impact of synthetic polymers not only on food products (migration issues) but on the entire environment (pollution). The science of packaging is also subjected to changes, resulting in development of novel biomaterials, biodegradable or not, with active, smart, edible and intelligent properties. Combining non-thermal processing with new materials opens completely new interdisciplinary area of interest for both food and material scientists. The aim of this review article is to give an insight in the latest research data about synergies between non-thermal processing technologies and selected packaging materials/concepts.
This review paper gives an insight into the effective delivery mechanisms for health-promoting substances and highlights the challenges of using antioxidants and bioactives in foods. The selection criteria for choosing bioactives and their extraction in bioavailable form with their adequate incorporation techniques and delivery mechanisms are covered. Moreover, an overview of existing methods for determination of bioactivity is given. The importance of scientifically evaluating the effects of foods or food components on consumer health before making claims about the healthiness is aligned. Finally, a scientific perspective on how to respond to the booming demand for health-promoting products is given, and we acknowledge that despite the work done, there are still many challenges that need to be overcome.
In this study, we investigated the impact of ultrasound treatment on barrier properties of linear low-density polyethylene (LLDPE) and acrylic/poly(vinylidene chloride) polypropylene (PPAcPVDC)-coated pouches intended for food packaging before and after exposure to food simulants. Packaging pouches were filled with two food simulants, namely ethanol (10% (v/v)) and acetic acid (3% (w/v)), in order to simulate food−packaging interaction and possible compound migration from packaging materials. Samples were subjected to an ultrasound water bath treatment for 5 min, 15 min, and 30 min at 60 °C (±2 °C) and with an amplitude of 100% as an equivalent to the heat-treatment conditions combined with an ultrasound effect. Furthermore, the effect of temperature on the polymer barrier (water vapour and oxygen permeability) properties was tested at 20 °C, 40 °C, and 60 °C. Results showed that PPAcPVDC possessed better properties of water vapour permeability and oxygen permeability properties to LLDPE. Statistical analyses showed a significant (p < 0.001) impact of ultrasound treatment on the overall migration value, regardless of the food simulant used.
Research background: Recently, natural plant extracts have been used to increase the nutritional value of food and to potentially reduce the absorbed fat and the formation of acrylamide in fried foods. Literature data on the use of edible polymers with nettle or olive leaf extracts are scarce. Experimental approach: The effect of novel coatings on colour, fat absorption, phenolic and sugar content, and acrylamide formation in deep-fat-fried fresh-cut potatoes was evaluated. Extracts of olive and nettle leaves were incorporated in carboxymethyl cellulose (CMC) and gum arabic, used as coatings for potatoes and applied before frying. This aimed to improve the nutritional quality of deep-fat-fried fresh-cut potatoes. Results and conclusions: Enrichment of the edible coatings with extracts resulted in a significant change in the visible colour of the potatoes before frying. Significant effect of the extract amount on the sensory characteristics of potatoes was also observed. Most importantly, the perception of characteristic potato odour and taste was not significantly affected by the coating. Although higher amounts of the extract (1.5%) resulted in higher phenolic mass fraction in fried potatoes, the sensory scores decreased. After frying, fat mass fraction in the coated potatoes was reduced by about 15% compared to the uncoated samples. The type of extract affected the total sugar mass fraction in fried potatoes, which was lower in the samples with coatings enriched with olive leaf than in those with nettle leaf. Only gum arabic coating had a reducing effect on acrylamide mass fraction by 17%. Based on all the obtained results, CMC and gum arabic coatings did not influence sensory properties, so they can be recommended as carriers of functional compounds or as a frying pre-treatment for potatoes with favourable effect on fat and acrylamide content. Novelty and scientific contribution: The knowledge obtained in this study can be exploited for preparation of coatings with functional compounds used as a pre-treatment for fried food with favourable effect on fat and acrylamide content.
Chitosan and pectin films were enriched with blackcurrant pomace powder (10 and 20% (w/w)), as bio-based material, to minimize food production losses and to increase the functional properties of produced films aimed at food coatings and wrappers. Water vapor permeability of active films increased up to 25%, moisture content for 27% in pectin-based ones, but water solubility was not significantly modified. Mechanical properties (tensile strength, elongation at break and Young's modulus) were mainly decreased due to the residual insoluble particles present in blackcurrant waste. FTIR analysis showed no significant changes between the film samples. The degradation temperatures, determined by DSC, were reduced by 18 °C for chitosan-based samples and of 32 °C lower for the pectin-based samples with blackcurrant powder, indicating a disturbance in polymer stability. The antioxidant activity of active films was increased up to 30-fold. Lightness and redness of dry films significantly changed depending on the polymer type. Significant color changes, especially in chitosan film formulations, were observed after exposure to different pH buffers. This effect is further explored in formulations that were used as color change indicators for intelligent biopackaging.
Antioxidants/chemistry , Biocompatible Materials/chemistry , Food Packaging , Membranes, Artificial , Smart Materials/chemistry , Waste Products , Chemical Phenomena , Chitosan/chemistry , Fruit/chemistry , Mechanical Phenomena , Spectrum Analysis
The main objective of this work is to develop and characterize novel bio-based sensor as intelligent food packaging film to monitor quality changes in fresh chicken meat. Chitosan (CS) and carboxymethyl cellulose (CMC) were used as polymer matrices for immobilization of pH sensitive color indicators. Generally considered as a food waste, blueberry (BP) and red grape skin pomace (RP) extracts were used as indicators at total phenolic content (TPC) of 0.06, 0.13, and 0.25 w/v for BP, and 0.006, 0.012, and 0.02 w/v for RP-based films. Color, mechanical, and intelligent material properties were determined. CS films were more elastic than CMC, while no significant changes in mechanical properties occurred after the addition of both extracts at all concentrations. Notable and eye recognizable color changes in dry films were seen. It was the most significant in the pH range from 4 to 7. For CMC-based films, color changed from violet to pink for BP extracts and from red to pink for RP extracts. For CS films, the changes were less significant. The color taint and intensity changed toward green in blueberry-based films and to orange in grape seed extract-based films. Significant color changes were observed after 46 hr in application tests on fresh chicken meat. This was correlated to pH changes of meat above 6 that was one of the parameters considered as an indication of spoilage. PRACTICAL APPLICATION: This work provides interesting data to food industry. It offers an idea and possibility of managing food waste from fruits and vegetables industry that makes problems and costs when needed to be disposed in a proper manner. Moreover, there is the possibility of producing novel kind of food packaging materials that could be used in order to check the end of food shelf-life in an inexpensive and natural way. Additional value lies in the fact that materials and procedures could be considered as sustainable.
Blueberry Plants/chemistry , Food Coloring Agents/analysis , Food Packaging/instrumentation , Plant Extracts/analysis , Polymers/chemistry , Vegetables/chemistry , Vitis/chemistry , Waste Products/analysis , Carboxymethylcellulose Sodium/chemistry , Chitosan/chemistry , Color , Fruit/chemistry , Hydrogen-Ion Concentration , Phenols/analysis
The aim of this study was to investigate the permeability properties of synthetic polymeric materials and their influence on the quality of packed chilled pork. Barrier properties of biaxially oriented polypropylene (BOPP) coated with acrylic/polyvinylidene chloride (BOPPAcPVDC) and biaxially oriented coextruded polypropylene (BOPPcoex), were tested on three gases: oxygen, carbon dioxide and nitrogen at different temperatures: 4⯰C, 20⯰C, 40⯰C and 60⯰C. Coefficients of permeability, diffusion and solubility were determined. The quality parameters of vacuum packed fresh chilled pork stored under controlled temperature over a 21-day period were evaluated with physico-chemical, sensory and microbiological analyses. Results showed that BOPPAcPVDC film provided better protection for fresh pork than BOPPcoex film in terms of physico-chemical, sensory and microbiological attributes, due to its greater barrier behaviour, with smaller permeance data (q) (0.98 to 324â¯cm3/m2 · d · bar) for BOPPAcPVDC, compared to BOPPcoex (227 to 6200â¯cm3/m2 · d · bar), in the temperature range from 4⯰C to 60⯰C (pâ¯<â¯.001). The shelf life of fresh pork packed in this film was doubled, from 7 to 14 days.
Food Packaging/methods , Polymers , Pork Meat/standards , Animals , Carbon Dioxide/chemistry , Food Microbiology , Food Storage/methods , Humans , Nitrogen/chemistry , Odorants , Oxygen/chemistry , Permeability , Pork Meat/analysis , Pork Meat/microbiology , Swine , Temperature , Vacuum
BACKGROUND: The increased use of synthetic packaging films has led to a high ecological problem due to their total non-biodegradability. Thus, there is a vital need to develop renewable and environmentally friendly bio-based polymeric materials. Films and coatings made from polysaccharide polymers, particularly chitosans and gelatins have good gas barrier properties and are envisaged more and more for applications in the biomedical and food fields, as well as for packaging. In this study a casting method was used to develop an edible plasticised film from chitosan and gelatin. Aiming to develop a blend film with enhanced properties, the effects of mixing chitosan (CS) and gelatin (G) in different proportions (CS:G, 75:25, 50:50, 25:75, w/w) on functional and physico-chemical properties have been studied. RESULTS: Mean film thickness increased linearly (R2 =0.999) with surface density of the film forming solution. An enhancement of mechanical properties by increasing the tensile strength (38.7±11 MPa for pure chitosan and 76.8±9 MPa for pure gelatin film) was also observed in blends, due to gelatin content.When the gelatin content in blend filmswas increased an improvement of both water vapour barrier properties [(4±0.3)×10(-10) g m(-1) s(-1) Pa(-1) for pure chitosan and (2.5±0.14)×10(-10) g m(-1) s(-1) Pa(-1) for pure gelatin, at 70% RH gradient] and oxygen barrier properties ((822.62±90.24)×10(-12) g m(-1) s(-1) Pa(-1) for blend film chitosan:gelatin (25:75 w/w) and (296.67±18.76)×10(-12) g m(-1) s(-1) Pa(-1) for pure gelatin was observed. Fourier transform infrared spectra of blend films showed a shift in the peak positions related to the amide groups (amide-I and amide-III) indicating interactions between biopolymers. CONCLUSIONS: Addition of gelatin in chitosan induced greater functional properties (mechanical, barrier) due to chemical interactions, suggesting an inter-penetrated network.
Biopolymers/chemistry , Chitosan/chemistry , Food Packaging , Gelatin/chemistry , Animals , Cattle , Oxygen/chemistry , Plasticizers/chemistry , Solubility , Tensile Strength , Water/chemistry
The influence of water vapour conditions on mass transport and barrier properties of chitosan based films and coatings were studied in relation to surface and structural properties. Water contact angles, material swelling, polymer degradation temperature, barrier properties (PO2, PCO2, WVP) and aroma diffusion coefficients were determined. The solvent nature and the presence of carvacrol influenced the surface and structural properties and then the barrier performance of activated chitosan films. Increasing RH from 0% to 100% led to a significant increase in material swelling. The plasticization effect of water was more pronounced at high humid environment, while at low RH the matrix plasticization was induced by carvacrol. The deposit of a thin chitosan layer on polyethylene decreased PO2 and PCO2 both in dry and humid conditions. The carvacrol release from the chitosan matrix was strongly influenced by RH. A temperature increase from 4 to 37°C also had an impact on carvacrol diffusivity but to a lesser extent than RH.
Chitosan/chemistry , Food Packaging/instrumentation , Monoterpenes/chemistry , Cymenes , Diffusion , Humidity , Water/analysis
Different chitosan coating solutions were tested with the aim of investigating their adhesion and wettability onto polyethylene film to improve packaging performance and provide antimicrobial properties. Surface wetting kinetics was monitored by contact angle measurements. Addition of ethanol and carvacrol improved wettability and adhesion of the thin chitosan layer. Structure, water vapour, O2, CO2 and air permeabilities of self supported chitosan films and coated polyethylene were determined. The formation of a thin chitosan layer on polyethylene improved gas barrier properties decreasing the Permeability Coefficient for oxygen and carbon dioxide ( [Formula: see text] , [Formula: see text] ) from 100 to 10,000 times. Presence of carvacrol in the chitosan coating layer increased [Formula: see text] , [Formula: see text] and Pair by a factor of ten. Moreover, it influenced film microstructure. However chitosan was shown to be good gas barrier film in the dry state.
Anti-Infective Agents/chemistry , Chitosan/chemistry , Monoterpenes/chemistry , Polyethylene/chemistry , Carbon Dioxide/chemistry , Cymenes , Oxygen/chemistry , Permeability , Surface Properties , Wettability
To help understand the organoleptic qualities of steam cooked foods, the kinetics of aroma release during cooking in a potato starch based model matrix was studied. Behaviour of components having a major impact in potato flavour were studied using solid phase micro extraction-gas chromatography (SPME-GC). Evolution of microstructure of potato starch model-matrix during steam cooking process was analyzed using environmental scanning electron microscopy (ESEM). Both aroma compounds that are naturally present in starch matrix and those that were added were analyzed. Both the aroma compounds naturally presented and those added had different behaviour depending on their physico-chemical properties (hydrophobicity, saturation vapour pressure, molecular weight, etc.). The physical state of potato starch influences of the retention of aromatized matrix with Starch gelatinization appearing to be the major phenomenon influencing aroma release.
Cooking/methods , Odorants , Solanum tuberosum , Microscopy, Electron, Scanning , Solanum tuberosum/ultrastructure , Starch/chemistry , Steam
The aim of this study was to investigate the shelf-life of commercial sliced dry fermented sausage during storage at different temperatures. Different laminate composition was used for vacuum and nitrogen (100% N(2)) packaging. The microbiological, physico-chemical and sensory parameters were analysed during 120 days storage at 4, 22 and 37°C. Packaging materials were analysed for their barrier characteristic (oxygen permeability). Sensory quality limited the shelf-life of sliced dry fermented sausages before the limiting effects of microbial proliferation occurred. Nitrogen atmosphere packaging allowed longer storage (>120 days) than vacuum (95 days) packaged dry fermented sausages at 4°C.
Consumer Behavior , Food Packaging/methods , Food Preservation/methods , Meat Products/analysis , Nitrogen , Temperature , Vacuum , Animals , Cattle , Diet , Fermentation , Food Microbiology , Food Storage , Humans , Meat Products/microbiology , Oxygen , Swine
