Effects of type of packaging material on physicochemical and sensory characteristics of deep‐fat‐fried banana chips

A storage study of deep‐fat‐fried banana chips was carried out for 8 weeks at ambient temperature (27 °C), using four types of packaging material: laminated aluminium foil (LAF), oriented polypropylene (OPP), polypropylene (PP) and low‐density polyethylene (LDPE). The physicochemical and sensory characteristics of the stored banana chips were analysed at weeks 0, 2, 4, 6 and 8. The quality parameters determined were moisture content, water activity (a_w), thiobarbituric acid‐reactive substances (TBARS), texture (breaking force), colour and sensory attributes. The moisture content, a_w, TBARS and breaking force values of all samples increased during storage. The colour also changed during storage, showing higher L and lower a and b values. Samples packed in LAF had the lowest moisture content, a_w, TBARS and breaking force values. The most notable sensory change that occurred during storage was a decrease in crispness. Samples packed in LAF had higher scores than the other three samples, whilst LDPE gave the lowest scores for crispness as well as product colour. There were no significant differences (P > 0.05) in rancid odour among samples packed in OPP, PP and LDPE. However, there were significant differences (P < 0.05) between samples packed in LAF and the other three samples, with LAF giving the lowest rancid odour. © 2002 Society of Chemical Industry     

Oxygen Requirements of Bacillus licheniformis and Bacillus subtilis in Tomato Juice; Ability to Grow in Aseptic Packages

Tomato juice was inoculated with spores of Bacillus subtilis and Bacillus licheniformis, placed in jars sealed with four polymers: oriented polypropylene (OPP), low density polypropylene with 4.5% ethyl vinyl acetate (LDPE + EVA), polyvinylidene chloride (PVDC), and polyethylene teraphthalate (PET); used in aseptic packages, serving as lids, heated in a boiling water bath for 10 min, and incubated at 35°C for up to 100 days. B. subtilis and-B. licheniformis grew at the surface of the food when OPP and LDPE + EVA were used, which caused the pH to rise above 4.6 in 60 days and above 5.0 within 100 days. The oxygen partial pressures were 0.20 and 0.18 atm per day, and the oxygen permeation ratios were 5.64 and 0.76 cc/day for LDPE + EVA and OPP, respectively.     

Barrier property and penetration traces in packaging films against Plodia interpunctella (Hübner) larvae and Tribolium castaneum (Herbst) adults

The barrier property of different types of plastic film (with or without pinholes) against two insects, Plodia interpunctella (Hübner) larvae and Tribolium castaneum (Herbst) adults, and the morphology of damage produced in these insects were investigated. Using a penetration apparatus, four types of plastic films varying in thickness were used for insect-penetration tests: casted polypropylene, 20 μm and 25 μm (CPP20 and CPP25); oriented polypropylene, 20 μm and 30 μm (OPP20 and OPP30); linear low-density polyethylene, 40 μm and 50 μm (LLDPE40 and LLDPE50); and polyethylene terephthalate 12 μm and 16 μm (PET12 and PET16). After being fixed and tested in the penetration apparatus, each film was cut into a disc shape and 10 holes (200 μm diameter) were made by a pin. The shape of film damage and the mouthparts of insects were observed using scanning electronic microscopy. Plodia interpunctella larvae could penetrate all films with pinholes, while T. castaneum adults were unable to penetrate any of the films tested, even those with pinholes. The penetration-percentages by P. interpunctella larvae were 38% (LLDPE40), 3% (LLDPE), 53% (CPP20), 37% (CPP25), 63% (OPP20), 43% (OPP30), 83% (PET12) and 63% (PET16). The elongation value, tensile strength and thickness of film were important factors in the penetration test. LLDPE, which has the highest elongation value and the lowest tensile strength value, was the film that best protected against insect penetration. In CPP and LLDPE films, there were many scratches and tears around the holes. In comparison, much less damage was observed around the holes in OPP and PET films. By observing the mouthparts of insects, it was determined that P. interpunctella larvae had sharper mandibles than those of T. castaneum adults.     

Effectiveness of antimicrobial coated oriented polypropylene/polyethylene films in sprout packaging

This study focused on the effect of antimicrobial incorporated soy protein isolate (SPI) coated oriented polypropylene/polyethylene (OPP/PE) packaging on extended shelf life of fresh sprouts. To develop antimicrobial SPI-coated packages, the minimum inhibitory and bactericidal concentrations of antimicrobial (allyl isothiocyanate, trans-cinnamaldehyde, garlic oil, and rosemary oil) and film properties of antimicrobial incorporated SPI films were investigated. Different concentrations (0.6–1.2%, v/v) of the SPI incorporated antimicrobial compounds were coated onto the OPP/PE film and heat-sealed. Packages containing sprouts (alfalfa, broccoli, and radish) were stored at 10 °C for 5 days. Significant reduction of the total microbial count of sprouts was observed in treated samples. Allyl isothiocyanate was the most effective antimicrobial compound, followed by garlic oil and trans-cinnamaldehyde.     

Effects of type of packaging material on shelf-life of fresh broccoli by means of changes in weight,colour and texture

Five polymeric films were studied to determine their ability to retain the colour, weight and texture of broccoli (Brassica oleracea L. var. Italica Monterey). The materials were oriented polypropylene (OPP), polyvinyl chloride (PVC) and two different low-density polyethylenes (LDPE), one of which contained a sachet reported to absorb ethylene. The broccoli was packaged and stored at 4 and 10 °C for 4 weeks. The weight, colour, chlorophyll content and texture were monitored during storage as well as O₂ and CO₂ concentrations inside the packages. Packaging prolonged the broccoli shelf-life by up to 14 days. The shelf-life varied depending on the packaging material and quality parameter considered. The atmosphere was modified inside the packages; however, no package provided the recommended atmosphere (O₂ 1–2% and CO₂ 5–10%) for broccoli. Packaging in OPP resulted in the highest CO₂ concentration, 6%, while the lowest O₂ concentration, 9%, was created in the LDPE package without a sachet for ethylene absorption. Storage in LDPE without ethylene absorber resulted in the overall longest shelf-life. Broccoli stored in PVC deteriorated faster than broccoli packaged in the other materials. The influence of packaging material was greater at the higher temperature.     

Active Banana Flour Nanocomposite Films Incorporated with Garlic Essential Oil as Multifunctional Packaging Material for Food Application

Active plasticized banana flour nanocomposite film (APBNF) incorporated with a different garlic essential oil (GO) content was formed using a solution casting to determine the film properties prior to the investigation of its effectiveness to preserve the roasted peanut quality. The GO concentration was positively correlated with the ultraviolet (UV) light barrier property and antioxidant activity indicating the ability to protect the packed food product from lipid oxidation. Additionally, incorporation of 1 mg/mL GO into APBNF showed the highest antioxidant activity and completely inhibited the growth of Aspergillus flavus. Fourier-transform infrared spectroscopy confirmed the functional group interactions between the film matrix and GO which act as an antioxidant and antimicrobial agent. Thus, APBNF incorporated with 1 mg/mL GO as an active packaging to preserve the quality of roasted peanuts was investigated comparing with a commercial plastic packaging of polyethylene terephthalate/low-density polyethylene (PET/LDPE; PET). The shelf life estimation of roasted peanuts packed in both packaging materials (APBNF and PET) based on the peroxide value (PV) was similar at high storage temperature (45 °C). Therefore, APBNF shows a multifunctional primary food packaging to maintain the quality of roasted peanuts or oily food products.     

Influence of Storage Time and Temperature on Absorption of Flavor Compounds from Solutions by Plastic Packaging Materials

ABSTRACT: Linear low-density polyethylene (LLDPE), oriented polypropylene (OPP), polycarbonate (PC), polyethylene terephthalate (PET film and PET bottle), and polyethylene naphthalate (PEN) were stored in a model solution containing 10 flavor compounds at 4, 20, and 40 °C and flavor absorption by the plastic materials was followed in time. The absorption rate and/or total amount absorbed increased considerably with temperature from 4 to 40 °C. Depending on storage temperature, total flavor absorption by the polyolefins (LLDPE and OPP) was 3 to 2400 times higher than by the polyesters (PC, PET, and PEN). Therefore, in the factor of flavor absorption, polyesters are preferred over polyolefins as packaging material.     

Altered Oxygen Permeation Through Packaging Polymers in Contact with Liquids—a Mathematical Model Confirmed in a Dilute Xanthan Gum Solution

The ability of liquids to reduce oxygen permeation through low density polyethylene (LDPE), oriented polypropylene (OPP), polyethylene terepthalate (PET), and polyvinylidene chloride (PVTDC) films was mathematically modeled using a water/xanthan solution as a model medium. For low barrier films (LDPE and OPP), the medium substantially reduced oxygen permeation. In PET, an intermediate barrier, the medium produced a recognizable, but minor reductions in permeation. For the highest barrier (PVDC), the medium's influence on permeation was almost unidentifiable. The effect of the medium's oxygen solubility constant and diffusion coefficient on permeation was also examined. For all films, reduction in permeation became significant only after solubility and diffusion values fell below 40% of water values.     

Development of anti-insect food packaging film containing a polyvinyl alcohol and cinnamon oil emulsion at a pilot plant scale

Anti-insect packaging films containing cinnamon oil (CO) encapsulated by polyvinyl alcohol (PVA) for repelling Plodia interpunctella (Hübner) larvae were manufactured using pilot plant scale instruments. The microcapsule emulsion of CO and PVA was printed onto polypropylene (PP) film as an ink mixture using the gravure printing method. The printed PP film was then laminated with a low-density polyethylene (LDPE) film to protect the printed side. Four types of multilayer films were produced: control film, 2% CO film, encapsulated 1% CO film, and encapsulated 2% CO film. When mechanical properties were assessed, tensile strength and elongation-at-break were not significantly different among films, whereas the Young's modulus values were different between the control film and the three types of CO-containing films. In a repellent test, 2% CO film repelled P. interpunctella larvae most effectively. For sensory evaluation, which was performed using milk chocolate, caramel soft candy, and cookies packaged with the produced films, the produced films did not affect the sensory characteristics. Therefore, the films printed with emulsions of CO and PVA could be applied in the food industry to help protect foods from infestation by P. interpunctella.     

The use of mechanical analyses,scanning electron microscopy and ultrasonic imaging to study the effects of high‐pressure processing on multilayer films

The effects of high‐pressure processing (HPP) on the mechanical and physical characteristics of eight high‐barrier multilayer films were investigated. These films were PET/SiO_x/LDPE, PET/Al₂O₃/LDPE, PET/PVDC/nylon/HDPE/PP, PE/nylon/EVOH/PE, PE/nylon/PE, metallised PET/EVA/LLDPE, PP/nylon/PP and PET/PVDC/EVA. In addition, PP was evaluated as a monolayer film for comparison purposes. Pouches made from these films were filled with distilled water, sealed, then pressure processed at 600 and 800 MPa for 5, 10 and 20 min at a process temperature of 45 °C. Pouches kept at atmospheric pressure were used as controls. Prior to and after HPP, all films were tested for tensile strength, percentage elongation and modulus of elasticity (at 50 cm min^?1) and imaged by scanning electron microscopy (SEM) and C‐mode scanning acoustic microscopy (C‐SAM). Results showed no significant changes in tensile strength, elongation and modulus of elasticity of all films after HPP. However, significant physical damage to metallised PET (MET‐PET) was identified by SEM and C‐SAM. Thus it could be concluded that MET‐PET is not suitable for batch‐type high‐pressure‐processed food packaging. It can also be concluded that the other materials investigated during this study are suitable for batch‐type high‐pressure‐processed food packaging. Copyright © 2003 Society of Chemical Industry     

Influence of different packaging systems on fresh-cut zucchini (Cucurbita pepo)

In this work different packaging strategies aimed to prolong the shelf life of minimally processed zucchini are presented. In particular, two different cultivars (Sofia and Diamante) were tested. The sliced zucchini were packaged in oriented polypropylene-based (OPP) bag and into a bio-polymeric film (COEX) under passive and active MAP. The investigated produce was stored at 5 °C for approximately 9 days. Headspace gas concentrations, pH, mass loss, sensory quality and viable cell load of main spoilage microorganisms were monitored for the entire observation period. In order to determine the respiration activity, O₂ and CO₂ concentrations were monitored not only in OPP and COEX packages but also in the headspace of an aluminum-based package. Results suggested that for Diamante cultivar OPP film under active and passive MAP showed slightly better performances in prolonging the shelf life, compared to COEX film; instead, for Sofia cultivar better results were obtained with OPP film only under active MAP conditions.Industrial relevanceThis paper suggests an effective packaging solution to delay the quality decay kinetic of two cultivars of fresh-cut zucchini. Due to changes in consumer attitudes, the proposed mild strategies to prolong the shelf life of ready-to-cook products could really gain widespread acceptance by industry of the minimally processed food sector. Due to great attention to the environmental pollution a biodegradable packaging system was also studied and compared to the common polypropylene-based film, even though the characteristics of this specific produce could not suggest the substitution with traditionally used plastic materials with eco-friendly polymers.     

Effect of a packaging material type on PAHs contents in oils and water

The aim of this study is to determine the extent of packaging material effect on the removal of polycyclic aromatic hydrocarbons (PAHs) from stored liquid media. Changes in PAHs contents were monitored in edible oils and water during their storage for 504 h. The most significant reduction in PAHs content was reported upon the use of polyethylene packagings. In the case of LDPE packagings, the Σ16PAHs content decreased to 40.07% (water) and 45.0% (rapeseed oil) of their initial level after 504 h. Most PAHs absorption occurred within the first 24 h of liquid media storage. In terms of PAHs absorption capability, the packages tested could be ordered as follows LDPE > HDPE > PET > glass. The experiment involving the re-use of LDPE, HDPE, and PET packagings earlier contaminated with PAHs demonstrated that their effective washing with detergents commonly used at household was impossible.     

Sensory Characteristics of Fresh-Cut Spinach Preserved by Combined Factors Methodology

Fresh‐cut spinach was treated with citric acid and ascorbic acid solutions and packaged in monooriented polypropylene (OPP) bags or low density polyethylene (LDPE) bags. Sensory attributes, chlorophyll retention, and weight loss were evaluated throughout refrigerated storage. Mathematical models were developed to analyze and predict the effect of the citric acid and ascorbic acid concentrations and storage time on off‐odor development, general appearance, wilting, browning, and color. Sensory attributes of fresh‐cut spinach decreased with storage time. Type of film affected off‐odor development, but did not influence visual sensory attributes. Chemical treatment and type of packaging film did not affect chlorophyll retention. Both types of packaging film controlled weight loss.     

Evaluation of biodegradable film packaging to improve the shelf-life of Boletus edulis wild edible mushrooms

The objective of this work was to evaluate the effect of poly(lactic acid) (PLA) based biodegradable film packaging combining 0.5% nisin antimicrobial polypeptide on the physicochemical and microbial quality of Boletus edulis wild edible mushrooms stored at 4 ± 1 °C. The experiment was set up by packaging mushrooms with extruded PLA films containing 0, 7.5, and 15 wt.% triethyl citrate plasticizer. The low-density polyethylene (LDPE) film was used as the control. Mushrooms stored in PLA films containing 7.5 and 15 wt.% plasticizer provided better retention of quality characteristics and received higher sensory ratings compared to mushrooms stored in pure PLA film and LDPE film. Samples with these two treatments underwent minimal changes in texture, PPO activity, total bacteria count, and sensory attributes. Results suggest that nisin in combination with plasticized PLA film has the potential to maintain B. edulis wild edible mushroom quality and extend its postharvest life to 18 days.Industrial relevanceB. edulis is one of the most commercialized mushrooms worldwide. However, as with all fresh mushrooms, there are severe preservation problems. Extruded PLA films containing triethyl citrate plasticizer plus antimicrobial agent nisin proved to be a suitable technology for mushroom conservation. This material exhibits an environmental-friendliness potential and a high versatility in food packaging.     

Use of hyperspectral imaging for evaluation of the shelf-life of fresh white button mushrooms (Agaricus bisporus) stored in different packaging films

The shelf life of mushrooms packaged using different polymer top-films (PVC, PET with different levels of perforations) was investigated using hyperspectral imaging (HSI). Packaged mushrooms were stored at 4 ± 0.2 °C for 14 days and weight loss, Hunter L, a, b values, maturity index and in-pack gas composition (% CO₂ and O₂) were also measured. The results obtained showed that the PET film perforated with small holes (1 mm in diameter) was generally superior in terms of maintaining overall mushroom quality. Regression models were built to correlate HSI data with measured quality parameters. Prediction maps were generated from hyperspectral data to show the model performance at pixel level. Results presented in this work show hyperspectral imaging can be used to evaluate the effect of different packaging systems on mushroom quality and that perforated PET packaging film is a viable alternative to the conventional PVC packaging, facilitating an increase in shelf life from 10 to 14 days.Industrial relevanceThe present study demonstrates HSI can be used for rapid evaluation of mushroom quality facilitating non-destructive evaluation of the effect of packaging systems on mushroom shelf-life. In addition, this work suggests an effective packaging solution to extend shelf life of mushrooms during storage. The proposed solution potentially improves the packaging recyclability as the same polymer material (PET) is used for the tray and top film, compared to conventional mushroom packaging where PVC is used for the top film and polypropylene (PP) for the tray.     

Development of antimicrobial polyolefin films containing lauroyl arginate and their use in the packaging of strawberries

Low-density polyethylene (LDPE) films were supplemented with lauroyl arginate ethyl (LAE) and characterized for physical, mechanical and antimicrobial properties as well as their use for fresh ‘Sulhyang’ strawberries packaging. LAE powder was added into the LDPE films at 0, 1, 3, 5, and 10% (w/w) and assessed for physical properties, gas permeation, thickness and color values. The results showed that incorporation of LAE into the LDPE matrix did not affect film thickness and color. The thermal stability of the LAE/LDPE film decreased with increasing concentrations of LAE. The LAE/LDPE film exhibited a rough surface and compact structure. Tensile strength were affected by addition of LAE on the other hand value of elongation at break were increased. The LAE/LDPE containing 5 and 10% LAE showed significant antimicrobial properties against mycelium growth. Further, 5 and 10% LAE/LDPE films were used for storage study and it showed that incorporation of LAE into LDPE film was an effective method for maintaining the quality of strawberries. Films containing LAE were very effective at reducing the total weight loss, maintaining firmness, and reduced fungal decay compared to the control strawberries at 10?°C. These results suggest that LAE/LDPE films are potential candidates for advanced packaging materials for the fruits packaging application.     

基于主成分分析法分析不同包装材料对双孢蘑菇品质的影响

采用主成分分析法定量分析5 种包装材料处理对双孢蘑菇品质影响,建立综合评价函数,筛选最佳包装材料。结果表明,9 个检测指标可简化成2 个主成分,累积方差贡献率达到86.224%,能够较好地反映原始数据的信息;不同包装膜处理双孢蘑菇的品质综合得分从高到低为：低压高密度聚乙烯＞高压低密度聚乙烯＞聚丙烯＞线性低密度聚乙烯＞乙烯-乙酸乙烯共聚物＞对照。由此可见,包装袋有利于双孢蘑菇贮藏保鲜,且低压高密度聚乙烯包装材料的保鲜效果最佳,为双孢蘑菇的贮藏保鲜提供了科学和直观的依据。     

Environmental assessment of a multilayer polymer bag for food packaging and preservation: An LCA approach

A screening of LCA for the evaluation of the damage arising from the life cycle of a bi-layer film bag for food packaging was carried out. Such packages are made of films obtained matching a layer of PA (Polyamide) with one of LDPE (Low-Density Polyethylene) and are mainly used for vacuum or modified atmosphere packaging and preservation of food. The study was conducted in accordance with the ISO standards 14040:2006 and 14044:2006 choosing, as the functional unit, 1 m² of plastic film delivered to the food production and packaging firms. The system boundaries go from cradle to factory-gate and include the phases of: the raw materials production and processing for the bag manufacturing; and the bag delivering to the food production and packaging plant.The damage assessment showed that the most impacting phases are the production of the Polyamide (PA6) and Low-Density Polyethylene (LDPE) granules due to the consumption of primary resources, such as natural gas and crude oil, in the amount of 53.55 dm³ and 132.42 g respectively, and to the emission in air of 295.73 g of carbon dioxide, 617 mg of nitrogen oxides, 12.1 mg of particulates, 349 mg of sulphur dioxide and 2.51 mg of aromatic hydrocarbons. The most affected damage category is Resources, followed by Climate Change, Human Health, and Ecosystem Quality.For minimising the total damage associated with the life cycle of the examined bag, the film thickness thinning and the use of a recycled PA granule were considered: the assessment showed that the two proposals allowed a reduction of about 25% and 15% (respectively) of the damage assessed.     

Changes during storage of dried Moringa oleifera leaves prepared by heat pump‐assisted dehumidified air drying

Moringa oleifera leaves contain phytochemicals that are retained during heat pump‐assisted dehumidified air drying. Changes in phytochemicals, antioxidant capacity and colour were evaluated at 15–35 °C, during storage of dried leaves in polypropylene (PP) or high barrier (PET/Al/PE) packaging for up to 6 months. The a_w of samples in PP increased from 0.373 to 0.669. Decreases in total phenolics were greatest at 35 °C in PP (48%) and least at 15 °C in PET/Al/PE (19%). There were few significant changes in DPPH inhibition after 2 months storage. There was little change in kaempferol and some increase in quercetin. During storage, samples became less green, suggesting breakdown in chlorophyll had occurred. The degradation of flavonoids followed first‐order kinetics. The half‐life for total flavonoids ranged from 2.13 to 1.47 months for samples stored in PP and from 2.59 to 1.83 months for samples stored in PET/Al/PE.