Shelf Life Of Fresh Foods Research Articles

The influence of storage conditions on hygiene condition and eicosapentaenoic acid oxidation in Nannochloropsis algae for sustainable food supply.

Nannochloropsis algae contain approximately 20% polyunsaturated fatty acids (PUFA) and hold significant potential for high-quality eicosapentaenoic acid (EPA) food industrialization. However, EPA in Nannochloropsis sp. is prone to oxidation, and microbial growth is a critical factor affecting the shelf life of fresh food. Storage composition and temperature are primary factors influencing microbial growth, yet these aspects are not fully understood. This study investigates the effects of temperature and encapsulation on EPA content in nano-products over time. Nano-powder and nanobeads derived from Nannochloropsis sp. served as raw materials. Additionally, changes in aerobic plate counts and coliform groups were monitored. The results indicated that nanobeads, due to their more complex processing and less mature packaging, were more susceptible to coliform contamination compared to nano-powder. In terms of EPA stability, nanobeads exhibited a longer storage life than nano-powder. The oxidation rate of both nano-powder and nanobeads was faster at 37 °C than at 25 °C. These findings can inform general shelf life estimation, rapid detection of total lipid content in nano-products and macro extraction of nano-oil. Moreover, they have significant implications for delaying EPA oxidation in nano-products and improving hygienic quality control for microbial detection. © 2024 Society of Chemical Industry.

Tannic acid-grafted Polylactic acid films: A nonmigrating antibacterial packaging for chilled fresh meat

Antimicrobial packaging can prolong the shelf life of fresh food, but those active antimicrobial substances may leach into the food and affect its quality. To avoid this phenome, the CC double bond was first incorporated into the chemical structure of polylactic acid (PLLA) and tannic acid (TA) to prepare poly(L-LA-co-butyrate itaconate) (PLBI) and photoactive tannic acid (pTA). Then pTA-grafted PLBI (pTA-g-PLBI) films were fabricated using UV curing technology. Results showed that pTA was successfully grafted onto the surface of PLBI film and formed a uniform layer. The pTA-g-PLBI films exhibited good bacteriostatic effects of 86 %, 90 %, and 96 % on E. coli, P. fluorescens, and S. aureus, respectively. Additionally, pTA-g-PLBI packaging reduced the relative abundance of Shewanella, Psychrobacter, and Pseudomonas in chilled pork and delayed the deterioration of pork for more than 5 days.

Food Irradiation - An Effective Technology for Food Safety and Security

This review will look at the irradiation-based food preservation method. A country’s ability to successfully adopt new technologies hinges on the availability of a suitable infrastructure. Irradiation has a low operating cost and utilizes minimal energy, but it requires significant capital investments and a minimum output volume to be economical. Over a specific threshold concentration, off tastes might develop and organoleptic changes can occur. At low quantities, however, not all pathogens and their poisons will be eliminated. Radiation therapy can be difficult to standardize because the results vary. How effectively the therapy works depends on several factors, including the commodity and cultivar, radiation dose, level of maturity, physiological status, temperature and environment before and after treatment, pre-and post-harvest treatments, and the sensitivity of the microorganisms to be controlled. Tolerance varies with the maturity level. Depending on public perception, regulatory actions, economics, and logistics associated with specific conditions, irradiation as a method of reducing foodborne diseases will be used. Not all foods can be irradiated in all situations due to technological and financial restrictions. Irradiation cannot indefinitely extend the shelf life of fresh food because the enzymes in foods like fruits, vegetables, fish, shellfish, meat, and poultry are still active and resistant to even high-dose radiation. If foods are exposed to too much radiation, they may lose flavor, especially if they are high in fat. Irradiated grains and legumes must be packaged carefully to prevent insect infestations because irradiation does not leave behind any harmful residue that would deter insects. Irradiation produces very little chemical changes in food, and the changes are similar to those by other preservation methods like heat. The application of irradiation technology will benefit farmers whose post-harvest grain lost value as a result of food spoilage, consumers who experience health problems as a result of virus exposure, exporters of such cereals, and ultimately the government, which gains economically from the hard cash generated. It will also benefit firms that package food, extension agents, technical assistants, and researchers. Radiation processing of food has been approved by various international statutory bodies and organizations to ensure ‘Food Security & Safety’, and overcome ‘Technical barrier to International Trade’ and currently is being practiced in more than 60 countries worldwide.

Enhancement of the mechanical properties and water barrier properties of thermoplastic starch nanocomposite films by chitin nanofibers: Biodegradable coating for extending banana shelf life

Starch-based films have limited applications due to their hydrophilicity and poor mechanical performance. Herein, thermoplastic starch (TPS) nanocomposite films with chitin nanofibers (ChNFs) extracted from shrimp-shell waste were successfully fabricated using a solvent casting method. We investigated the effects of the ChNF loadings on the physical, mechanical, and water vapor barrier properties of the nanocomposite films. The well-dispersed ChNFs within the soft matrix associated with the formation of interfacial bonding between ChNFs and starch facilitated the efficient stress transfer from the soft matrix to the stiff ChNFs. Additionally, the presence of ChNFs created tortuous pathways within the films, which could impede the diffusion of water molecules. This resulted in a significant improvement in the mechanical properties, wettability, water resistance, and water vapor barrier properties of the nanocomposites. Compared to the results obtained from the neat TPS films, the TPS nanocomposites reinforced with ChNFs exhibited a 300% higher tensile stress, a 603% Young's modulus, and a considerable increase in the water contact angle, shifting from 86.2° to 98.6°. Furthermore, the ChNF-reinforced nanocomposite films showed no fragmentation after being soaked in water for 12 h under vigorous stirring, whereas the neat TPS films disintegrated under the same conditions. Interestingly, we found that coating a suspension of TPS and ChNFs on bananas effectively delayed their aging, preventing the color change from green to yellow. This promising result demonstrates the potential of the developed coating to extend the shelf life of fresh food produce, reducing food waste and the reliance on single-use petroleum-based packaging.

Development and Characterization of an Edible Zein/Shellac Composite Film Loaded with Curcumin.

The development of functional edible films is promising for the food industry, and improving the water barrier of edible films has been a research challenge in recent years. In this study, curcumin (Cur) was added to zein (Z) and shellac (S) to prepare an edible composite film with a strong water barrier and antioxidant properties. The addition of curcumin significantly reduced the water vapor permeability (WVP), water solubility (WS), and elongation at break (EB), and it clearly improved the tensile strength (TS), water contact angle (WCA), and optical properties of the composite film. The ZS-Cur films were characterized by SEM, FT-IR, XRD, DSC, and TGA; the results indicated that hydrogen bonds were formed among the curcumin, zein, and shellac, which changed the microstructure and improved the thermal stability of the film. A test of curcumin release behavior showed controlled release of curcumin from the film matrix. ZS-Cur films displayed remarkable pH responsiveness, strong antioxidant properties, and inhibitory effects on E. coli. Therefore, the insoluble active food packaging prepared in this study provides a new strategy for the development of functional edible films and also provides a possibility for the application of edible films to extend the shelf life of fresh food.

Climate-Conscious Food Preserving Technologies for Food Waste Prevention

Global food production is responsible for around 26% of greenhouse gas emissions caused by human activities. Notably, 6% of these emissions are caused by unconsumed food. Both traditional and current climate-conscious technologies for food preservatives that assure food waste reduction are discussed. This review investigates the potential of smart packaging biosensors and natural antimicrobial agents in fostering environmentally friendly, cutting-edge food systems. Specifically, it highlights the studies that explore the use of natural antimicrobial agents of calcined corals in active packaging systems for storing milk. The finding revealed that this method had a significant impact on maximizing the shelf life of fresh food. Furthermore, this review discusses the concept of smart packaging of food, focusing on biopolymer-based nanocomposites and biosensors, which have gained increasing attention in the food industry due to concerns about food safety and quality. The review also examines the efforts of the United Arab Emirates (UAE) to combat food waste through the initiatives such as UAE Food Bank, Winnow, and Ne’ma which is the national food loss and waste project. These technologies and practices have the potential to guarantee food safety, preserve quality, and reduce waste, but there are still issues with cost, biocompatibility, and consumer acceptance.

AgNP anchored carbon dots and chitin nanowhisker embedded soy protein isolate films with freshness preservation for active packaging

Biodegradable substitutes to the commonly practiced packaging materials are always in high demand. Active biopolymer film was obtained from soy-protein isolate (SPI) and the antibacterial properties were introduced by incorporating silver nanoparticles. Active bio-composite films incorporating silver nanoparticles (AgNP) are much sought after in the food packaging industry owing to their ability to extend the shelf life of fresh foods. But the toxicity of the ingredients used for preparation (mainly the reducing agents) and the poor stability limits their usage for the aforementioned application. Herein, to counter these limitations, we have adopted an environment-friendly method where carbon dot (CD) prepared from soy protein isolate was used to prepare AgNPs. AgNPs (1% wt.) and different concentrations of chitin nano whisker (CNW) (2–10% wt.) were added to soy protein isolate to fabricate nanocomposite films. The subsequent effect on the latter’s tensile property, moisture content, thermal property and morphological characteristics were noted. Here, for the first time, the steam explosion technique was used for the preparation of CNW which resulted in highly crystalline CNW with good antibacterial properties. It was observed that the mechanical strength and thermal stability of SPI film were significantly increased and the moisture content decreased with the addition of CNW and AgNP. The synergistic effect of AgNP and CNW imparted excellent antioxidant, antibacterial and antifungal properties to the SPI film thus enabling the SPI film to extend the shelf life of the food material that was packed using the same. Commercial production of such SPI films would revolutionize the food packing industry given its health benefits and its cost-effectiveness.

Green Silver Nanoparticles Embedded in Cellulosic Network for Fresh Food Packaging

The demand for increasing the shelf life of fresh food as well as the need for protecting the food against foodborne infections warrant the demand for increasing the shelf life of fresh food. The incorporation of nanoparticles into the packaging material can enhance the preservation of perishable foods. Silver nanoparticles (AgNPs), in particular, have antibacterial, anti-mold, anti-yeast, and anti-viral activities can be embedded into the biodegradable packaging materials for this purpose. This study focuses on antimicrobial packaging materials for food by mixing the extracts of different plants with silver nitrate and depositing this mixture as a layer on the blotting papers, which are thick sheets of paper made of cellulose. Because the blotting papers are highly absorbent and porous, silver nitrate solution along with the plant extracts can be easily applied and allowed for in situ synthesis of AgNPs. Subsequently, these papers were analyzed and characterized using scanning electron microscopy, transmission electron microscopy, atomic absorption spectroscopy, and energy dispersive X-ray analysis. The coated paper exhibited good antibacterial activity against Escherichia coli and Staphylococcus aureus. Furthermore, the coated paper when used as a packaging material for tomatoes and coriander leaf, the shelf life was extended to about 30 days and 15 days respectively. The prepared cost-effective silver packing material can be used in food packaging for various perishable foods.

Zeolite/Zinc-polypeptide를 코팅한 폴리프로필렌필름의 항균 및 항진균 특성에 관한 연구

This study is for the application of functional antibacterial packaging to fresh food. Zeolite/Zinc-polypeptide was coated on PP film at concentrations of 5%, 10%, and 15%, degree of dispersion was verified through FESEM and FT-IR analysis. In addition, the antibacterial and antifungal properties of the films were analyzed according to the control group and the concentration of coating materials. As a result, the degree of dispersion of coating material was irregular but wide, depending on the concentration of Zeolite/Zinc-polypeptide on the surface of PP film. The antibacterial effect against E. coli was over 99.9%, and the growth of R. oryzae was inhibited about 70%. Therefore, it was confirmed that Zeolite/Zinc-polypeptide had antibacterial and antifungal properties against E. coli and R. oryzae even after coated on PP film. In conclusion, Zeolite/Zinc-polypeptide coating film is expected to be effective in preventing corruption and improving the shelf life of fresh food as a functional packaging material. In order to be applied to various fresh foods in the future, storage experiments are additionally required with temperature and humidity conditions according to fresh foods.

Effects of incorporating calcined corals as natural antimicrobial agent into active packaging system for milk storage.

A series of nylon (NY)/linear low-density polyethylene (LLDPE) containing calcined corals (NY/LL-CORALS) composite films were prepared using the cast extrusion method. We investigated the effect of different contents of incorporated calcined corals on the physical properties and antimicrobial activity of the composite films as well as their feasibility for milk storage applications. The results indicated that the main compound in calcined corals was calcium oxide (CaO). As the calcined corals content increased, the crystallinity of the composite films slightly decreased, but no significant changes in their thermal stability and permeability were observed. The NY/LL-CORALS composite films exhibited excellent antimicrobial performance against Escherichia coli and Staphylococcus aureus. Notably, the NY/LL-CORALS packaging significantly extended the lag time of bacteria and delayed the bacterial growth cycle in milk during storage. Thus, the NY/LL-CORALS composite films could be a potential food packaging material that could prolong the shelf life of fresh food.

Effect of various additives on the properties of the films and coatings derived from hydroxypropyl methylcellulose-A review.

Edible films and coating materials are commonly used as appropriate packaging materials to extend the shelf life of fresh food. Due to all their properties, edible film and coating materials have been received much attention. They are biodegradable, edible, and good barrier against environmental parameters; thereby, they could carry and deliver food additives protecting food quality. Hydroxypropyl methylcellulose (HPMC), a cellulose derivatives, can act as an excellent film‐forming agent for coating food produces. The aim of this study was to provide an overview of the HPMC properties and investigate the effects of various additives on its film‐forming properties, such as rheological behavior, water vapor, and gas permeability, as well as mechanical, optical, antioxidant, and antimicrobial properties, with a focus on the recent progress and outputs, which has been recently published. Hydroxypropyl methylcellulose is prone to be commonly used as an advanced film‐forming and coating materials for the sake of well miscibility with a wide range of organic and inorganic materials. However, this polymer requires further improvements regarding moisture susceptibility and thermal properties.

Alginate Biocomposite Films Incorporated with Cinnamon Essential Oil Nanoemulsions: Physical, Mechanical, and Antibacterial Properties

Alginate-based antibacterial biocomposite films were prepared by incorporating with cinnamon essential oil nanoemulsions (CEO-NE). CEO-NE was first prepared by mixing and homogenizing the oil phase and aqueous phase containing polysorbate 80 (Tween 80), using a probe-type ultrasonication equipment. The biocomposite films were then prepared by incorporating the CEO-NE to an aqueous solution of alginate and glycerol, homogenizing, casting, and drying. The mean droplet size, zeta potential, and polydispersity index of the CEO-NE were 92.2 nm, −15.58 mV, and 0.25, respectively. Young’s modulus of the CEO-NE/alginate biocomposite films was significantly increased with an increasing concentration of CEO-NE, while their elongation at break was significantly decreased. However, the tensile strength of the CEO-NE/alginate biocomposite films was not significantly changed. The maximum tensile strength and elongation at break of the biocomposite films were 15.63 MPa and 23.67%, respectively, corresponding to the biocomposite films containing 20% CEO-NE. The biocomposite films containing 20% CEO-NE also showed strong antibacterial effects against Salmonella typhimurium, Bacillus cereus, Escherichia coli, and Staphylococcus aureus, achieving inhibition zones from 29.7 to 53.0 mm. These results show the potential of the CEO-NE/alginate biocomposite films as antibacterial packaging for extending the shelf life of fresh foods.

A new volatile antimicrobial agent-releasing patch for preserving fresh foods

Abstract Active packaging that releases antibacterial volatile oils has been one of the most promising approaches to protecting fresh food and increasing its shelf life. Existing strategies, however, are limited by the need to adjust packaging material to suit the particular antimicrobial and environmental conditions. Here we describe a new patch made of absorbent polymers and two volatile antimicrobial compounds, carvacrol and tea tree oil (TTO). After assessing several different polymers, microcrystalline cellulose was chosen as the absorbent matrix due to its high level of absorption, around 90% of its weight. Carvacrol and TTO were released into the head compartment in a controlled manner, reaching a plateau within 20 min. Both carvacrol and TTO patches exhibited marked antimicrobial activity against Escherichia coli, Listeria monocytogenes, Alternaria alternate, Penicillium commune and moderate activity against Pseudomonas putida. Visual and mechanical evaluation of strawberries and pumpkin specimens showed that carvacrol patches had the best effect on increasing shelf life compared to TTO and empty patches. The versatility of the patch, the simplicity of its production and its effectiveness demonstrated here make it very attractive as a new platform to extend the shelf life of fresh foods.

Quality comparison of grass carp and salmon fillets packaged in modified atmosphere with different composite films

AbstractGrass carp fillets (without dark meat) and salmon fillets were stored in modified atmosphere packaging (MAP) with a gas mixture of 10% O2, 60% CO2, and 30% N2 for up to 12 days at 4 °C. Effects of three commercial MAP composite films, that is, F1 from Sealed Air, F2 from Amcor, and F3 from Bemis, on contents of CO2 and O2, and quality indicators including total viable count (TVC), total volatile basic nitrogen (TVB‐N), thiobarbituric acid (TBA), K value, pH, and color difference were investigated. It was observed that O2 content, pH, and TBA in grass carp fillets were higher than those of salmon fillets, while CO2 content and color difference were lower. F1 could maintain the quality of both fillets better than F2 and F3, with F3 being the worst. Principal component analysis showed the scores of F1, F2, and F3 for packaging grass carp and salmon fillets were 24.840, 26.570, and 25.162, and 24.863, 27.086, and 24.878, respectively, with F1 being the best for keeping the quality. The relationship between rate constant k and film oxygen permeability for describing kinetic change of TVC and TVB‐N during MAP storage for both fillets were also determined in the study.Practical applicationsGrass carp and salmon are very common species of fish with the largest reported production internationally. As highly perishable products, the extension of their shelf‐life is an important issue for in the industry. Modified atmosphere packaging (MAP) is an effective method for extending the shelf life of fresh foods. This study compared three commercial MAP composite films, that is, F1 from Sealed Air, F2 from Amcor, and F3 from Bemis, on contents of CO2 and O2, and quality indicators including total viable count (TVC), total volatile basic nitrogen (TVB‐N), thiobarbituric acid (TBA), K value, pH, and color difference for grass carp fillets (without dark meat) and salmon fillets stored in MAP, and indicated that F1 with composition of PP/Tie/Nylon6/EVOH/Nylon6/Tie/LLDPE was the best for keeping their quality. The current results should provide valuable information for the industry and retailers to supply high quality fresh aquatic products to the consumers.

Alginate edible films containing microencapsulated lemongrass oil or citral: effect of encapsulating agent and storage time on physical and antimicrobial properties.

Active edible films have been proposed as an alternative to extend shelf life of fresh foods. Most essential oils have antimicrobial properties; however, storage conditions could reduce their activity. To avoid this effect the essential oil (EO) can be microencapsulated prior to film casting. The aim of this study was to determine the effects of the type of encapsulating agent (EA), type of EO and storage time on physical properties and antimicrobial activity of alginate-based films against Escherichia coli ATCC 25922. Trehalose (TH), Capsul® (CAP) and Tween 20 (Tw20) were used as EA. Lemongrass essential oil (LMO) and citral were used as active agents. The results showed that the type of EA affected the stability of the film forming-emulsions as well as the changes in opacity and colour of the films during storage but not the antimicrobial activity of them. Both microencapsulated EOs showed a prolonged release from the alginate films during the 28days of storage. Trehalose was selected to encapsulate both active compounds because the films made with this microencapsulated EA showed the greatest physical stability and the lowest color variation among all the films studied.

Development of Lightweight Insulation Body for Refrigerated Vehicles by Using Composite Materials

Energy demand in refrigerated vehicles account for about 5% of fossil fuel consumption globally and this percentage is expected to rise as perishable raw food continue to enjoy significant patronage of refrigerated vehicles which provide low temperature condition for its sustenance. Sustaining the shelf life of fresh food remains a herculean task to most farmers as cold chain must remain unbroken in order to maintain the quality of fresh food. The concept of this research is to reduce energy consumption in refrigerated vehicles through lightweight insulated panel as this medium could effectively reduce the payload of the entire vehicle. Part of the progress made in this work, is to develop five different composite cover sheet for insulated panel using fibre loading and orientation as manufacturing parameters and results show that the oriented reinforced composite materials offer significant weight reduction compared to unoriented composite cover sheet. The panel weight of these new materials were estimated using all the conceptual parameters of a refrigerated vehicle and the results indicate that composite reinforced with 10%wt. of fibre at 30o orientation in the matrix, offers the best panel weight reduction with 5.2380kg/m2 and 6.7380kg/m2 for 50mm and 100mm insulation thicknesses, respectively.

Energy Conservation in Refrigerated Vehicles through Prospective Light Weight Insulated Panel

Sustaining the shelf life of fresh food remains a herculean task to most farmers as cold chain must remain unbroken in order to maintain the quality of fresh food. The concept of this research is to reduce energy consumption in refrigerated vehicles through light weight insulated panel as this medium could effectively reduce the payload of the entire vehicle. Part of the progress made in this work, is to develop five different composite cover sheet for insulated panel using fibre loading and orientation as manufacturing parameters and results show that oriented reinforced composite materials offer significant weight reduction compared to un-oriented composite cover sheet. The panel weight of these new materials were estimated using all the conceptual parameters of a refrigerated vehicle and the results indicate that composite reinforced with 10%wt. of fibre at 30o orientation in the matrix, offers the best panel weight reduction with 5.2380Kg/m2 and 6.7380Kg/m2 for 50mm and 100mm insulation thicknesses, respectively.

Characterization and antimicrobial effect of starch-based edible coating suspensions

Starch is an edible polymer which may be used in combination with antimicrobial agents as thin coatings to extend shelf life of foods. This work was aimed to design and characterize an oleic acid nanoemulsion (OAN), as part of starch-based edible coating (EC) suspensions, incorporated with a mixture of three natural antimicrobials: lactic acid (ALA), nisin (NIS), and lauric arginate (LAE). OANs contained finely dispersed hydrophobic particles of 95.9 ± 4.8 nm providing a stable suspension, and high optical clarity (27843.6 ± 230.2 Transmittance units/nm). The EC suspension was prepared using waxy, acetylated cross linked, or oxidized starches (4% w/v) mixed with sorbitol (0.8 g/g starch), to which the nanoemulsion was added, and physicochemically characterized. The ζ potential of the OAN showed a large value (−35.08 ± 1.26 mV). Despite EC suspensions showed low ζ potential values, no particles aggregation was observed after 4 months storage. The wettability coefficient (Ws) of EC suspensions was tested on three model foods, where those of waxy and oxidized starches gave Ws = −0.01 ± 0.0 mN/m for fresh pork meat, with contact angle of 0°. The EC suspension from waxy starch was tested to inhibit Brochothrix thermosphacta, Listeria monocytogenes Scott A and Micrococcus luteus ATCC 11509, alone, and in mixture. From a mixture design of experiments the optimum combination of antimicrobial agents was 3.75 μg/mL NIS, 0.0625 mg/mL LAE, and 17.5 mg/mL ALA, which incorporated into EC suspensions produced similar antimicrobial effect. The properties of active EC suspensions may be used as coatings to extend the shelf life of fresh foods.

Characterization of Edible Active Coating Based on Alginate-Thyme Oil-Propionic Acid for the Preservation of Fresh Chicken Breast Fillets

Chicken meat presents serious problems of processing and storage. Edible coatings are used commercially to improve the shelf life of fresh foods. The aim of this study is to develop an effective antimicrobial edible coating to improve the shelf life and safety of fresh chicken meat. The effect of propionic acid and thyme essential oils as antimicrobial and antioxidant compounds incorporated into alginate-based edible coating was evaluated. Physical, antimicrobial and sensorial analyses were performed in coated and uncoated samples. Sensorial analysis showed no significant differences between coated and uncoated samples, which do not influence the buying decisions of consumers. The pH of the meat surface, color and sensorial analysis changed during storage time, showing similar behavior between coatings, the principal parameters to determine the shelf life of this product were weight loss and microbiological deterioration, where coatings had different behaviors. The selected coating increased the shelf life by about 33% with the lowest dehydration.

Active packaging of food products: recent trends

PurposeThe purpose of this paper is to review the recent trends in the development of active packaging (AP) for foods.Design/methodology/approachThe most up‐to‐date and pertinent studies within the literature have been included and summated in this paper.FindingsFresh foods are widely consumed and are becoming a major component of the international food market. During the last decades, the social and scientific modernization, the boom in customer's needs and demands, along with the major changes in the way food products are manufactured, distributed and retailed, led to the development of alternative or novel methods for the production and preservation of food products. This review will present the most comprehensive and current overview of the widely available, scattered information about the different AP technologies for the control of various critical parameters responsible for the quality and shelf life of fresh foods with an interest to stimulate further research to optimize different quality parameters.Originality/valueThis paper offers a holistic view that would guide a reader to identify the recent developments in the field of AP.