Effects of chitosan coating on shelf-life of ready-to-cook meat products during chilled storage

Combined Effect of an Active AgIon® Absorbent Pad and a Chitosan Coating on the Preservation of Fresh Beef

In the present study, the combined effect of an AgIon® antimicrobial absorbent (Ζ) pad and a chitosan coating (C) on the preservation of fresh beef stored aerobically at 5 °C was investigated. Microbiological, physicochemical, and sensory attributes were monitored for up to 10 days of storage. The microbiological data indicated that the C and chitosan coating plus absorbent pad (CZ) treatments were the most efficient in reducing total viable counts (TVC) by 4.09 and 3.53 log cfu/g compared to the control W and Z treatments on day 4 of storage (p < 0.05). An analogous reduction in the counts of the other microbial groups monitored was recorded. pH values were ca. 5.7 for treatments W and Z and 5.45 for treatments C and CZ on day 4 of storage (p < 0.05). The total volatile basic nitrogen (TVB-N) values remained <20 mg/100 g for all treatments on day 4 and for treatments C and CZ on day 10 of storage. The total color difference values decreased (p < 0.05) during storage for treatments W and Z, but remained constant for treatments C and CZ. Based on sensory, microbiological and physico-chemical data, beef shelf life was ca ^# + 3 days for samples W and Z and at least 10 + 3 days for samples C and CZ. Between the two antimicrobial treatments, chitosan was considerably more effective than the AgIon® antimicrobial absorbent pad, which showed practically no antimicrobial activity in direct contact with beef meat.

Evaluation of whey protein coating containing nanoliposome dill (Anethum graveolens L.) essential oil on microbial, physicochemical and sensory changes of rainbow trout fish

The aim of this study was to investigate the effect of whey coating containing dill (Anethum graveolens L.) essential oil nanoliposome on the physicochemical, microbiological and sensory characteristics of rainbow trout (Oncorhynchus mykiss). Treatments comprise: sample without coating (control), coating containing whey, coating containing whey with essential oil (whey-EO) and coating containing whey with nano EO (whey-NEO). The particle size, zeta potential, polydispersity index and the encapsulation efficiency were ranged from 142 to 159 nm, -16.3 to -11.7 mV, 0.79 to 0.88 Mw/Mn and 45.85-70.01 %, respectively. Microbial analysis, after 21 days, the maximum and minimum of TVC (total viable counts), TPC (total psychrophilic counts) and LAB (lactic acid bacteria) counts were related to control (8.16 for TVC, 8.46 for TPC and 7.7 log CFU/g for LAB) and whey + NEO (7 for TVC, 7.3 for TPC and 6.16 log CFU/g for LAB), respectively. Also, results of pH, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and total volatile base-nitrogen (TVB-N) after 21 days were ranged from 6.3 (whey-NEO) to 7.5 (control), from 11.5(whey-NEO) to 20.9 mEq/Kg (control), from 5.23(whey-NEO) to 8.34 mg MDA/kg (control) and from 22.5 (whey-NEO) to 37 mg N/100 g (control), respectively. Finally, in all sensory evaluation items (texture, off-odor, discoloration and red color), the best result after 21 days was related to whey-NEO (score = 1). Consequently, the edible coating comprising whey and nanoliposome of EO could be effective to the maintenance of fish's microbiological, physicochemical, and sensory properties.

Design and Development of an Edible Coating for a Ready-to-Eat Fish Product

The application of chitosan and alginate coatings for a ready-to-eat (RTE) baked fish product was studied. An experimental design was used to investigate the effect of coating a polysaccharide concentration and glycerol addition on the safety (microbial growth) and quality (water loss and lipid oxidation) of an RTE fish product under optimal and abused storage conditions. The results showed that a chitosan coating with 1% (w/v) chitosan in 1% (v/v) acetic acid and 15% (w/w chitosan) glycerol, or a 1% (w/v) alginate coating with no glycerol and no crosslinking, showed the best performance in controlling the tested safety and quality parameters. The desirability method was used to identify the shelf lives of chitosan, alginate, and double-coated RTE products. The chitosan-coated samples showed the best performance with a three-fold shelf-life extension compared to the uncoated products stored at 4 °C. Moreover, the tested coatings demonstrated their ability to provide protective functions under abused storage conditions. These results strongly suggest that edible coatings have significant potential in enhancing the shelf life and safety of ready-to-eat (RTE) fish products.

Preparation, physicochemical and biological evaluation of chitosan Pleurotus ostreatus polysaccharides active films for food packaging

The aim of this study was to create CS-POP composite films by blending Pleurotus ostreatus stalk polysaccharides (POP) and chitosan (CS). The effects of adding different concentrations (0 %, 0.25 %, 0.5 %, 0.75 %, and 1 %) of POP on the mechanical, barrier, and optical properties of the CS films were investigated. When the POP content is at 0.5 %, the tensile strength of the composite film reaches its maximum value at 13.691 MPa, showing a significant improvement compared to the tensile strength of the pure CS film. The structure of the CS and CS-POP composite films was characterized by FT-IR spectroscopy, XRD, TGA and SEM. The results indicate that due to the interaction between the two types of CS and POP, the formation of Schiff base, and the intermolecular hydrogen bonds between CS and POP, the addition of POP to CS films can result in a smoother and more stable crystalline structure in the composite film. The CS-POP composite films exhibited enhanced antioxidant and antibacterial activity compared to the CS films alone, with the highest DPPH scavenging activity of 72.43 %. The composite films also showed significant inhibitory effects on the growth of E. coli.

The effect of essential oil of Anethum graveolens L. seed and gallic acid (free and nano forms) on microbial, chemical and sensory characteristics in minced meat during storage at 4 °C

The aim of this study was to evaluate the effect of gallic acid (GA) and essential oil (EO) of Anethum graveolens L. seed (forms of nanoliposome and free) on bacteriological, chemical and sensory properties of minced meat during storage. In this research, Escherichia coli (gram negative) and Staphylococcus aureus (gram positive) were used to examine the effect of these compounds on meat. The particle sizes (z-average diameter) of prepared nanoliposomes of EO and GA were in the range of 141 to 165 nm and 146-160 nm, respectively and the efficiency of encapsulation (EE %) in the current research was 51.76-69.8% in nano EO (NEO) and 53.23-67.07% in nano gallic acid (N-GA). Also, the outcomes indicated the treatment containing nano-liposomes had a better antimicrobial effect in both of bacteria. In present study, the Minimum Inhibitory Concentration (MIC) of GA, N-GA, EO and NEO for S. aureus was 0.62 ± 0.01, 0.62 ± 0.02, 0.62 ± 0.01 and 0.62 ± 0.01 mg/mL, respectively, and for E. coli was 0.62 ± 0.01, 0.62 ± 0.01, 1.25 ± 0.1 and 1.25 ± 0.1 mg/mL, respectively. Also, the results showed MBC (The Minimum Bactericidal Concentration) of GA, N-GA, EO and NEO for S. aureus was 0.62 ± 0.02, 0.62 ± 0.03, 1.25 ± 0.1 and 1.25 ± 0.1 mg/mL, respectively, and for E. coli was0.62 ± 0.01, 1.25 ± 0.1, 2.5 ± 0.2, 2.5 ± 0.2 mg/mL, respectively. The highest and lowest of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging were detected, in the Butylated hydroxytoluene (BHT) 200 and EO1%, respectively. Furthermore, after 18 day, minimum pH and Total volatile basic nitrogen (TVB-N) value were related to the N-GA2% on S. aureus with pH = 6.5 and NEO group (27 mg N/100 g), respectively. Finally, the treatment of NEO showed a higher acceptance score of sensory evaluation after 18 days. According to the outcomes of current investigation, the use of nanocapsulated EO and GA are effective (as a coating for food storage) and can increase the shelf life of minced meat.

Effect of a Chitosan Coating Enriched with an Olive Leaf Extract on the Characteristics of Pork Burgers

Chitosan coatings have been investigated for improving food shelf-life. The addition of an olive leaf extract could enhance its beneficial effect. The aim of this study was to evaluate the effectiveness of an olive leaf extract added to a chitosan coating in delaying deterioration in refrigerated pork burgers without additives packaged under a 40% oxygen and 60% carbon dioxide modified atmosphere. Some general parameters (microbial counts, instrumental color and texture, and lipid and protein oxidation) were measured over the storage of pork burgers without coating (Control), with a chitosan-based coating (Chitosan) and with a chitosan-based coating enriched with an olive leaf extract (Chitoex). The coating impacted the effect of the storage time on most parameters. Both coatings were especially effective at limiting the changes that occur over time in the headspace gases, some texture parameters (hardness, gumminess, and chewiness) and lipid oxidation, although the effect on the microbial counts was weak. Chitoex was more effective than Chitosan at preventing changes in the headspace gases on day 11 and in lipid oxidation on all the sampling days. In conclusion, the Chitoex coating could be useful for prolonging the storage of pork burgers by preventing changes in texture and reducing lipid oxidation.

Encapsulation of Tea Polyphenol in Zein through Complex Coacervation Technique to Control the Release of the Phenolic Compound from Gelatin-Zein Composite Film

Green tea polyphenol (TP) was encapsulated in zein and fabricated into a gelatin-zein composite film by complex coacervation. Transglutaminase (TG) crosslinking was employed to obtain a compact structural orientation of the film to prolong the release of bioactive compounds. The encapsulation efficiency of zein and the TP release rate from the composite film were investigated. The retention rate was over 30% and 80% after film fabrication and storage, respectively. Crosslinking decreased the diffusion coefficient by half, thus improving the release of TP from the film. The antioxidant properties were satisfactory after discharge from the film detected by DPPH/ABTS scavenging. The value of crosslinking degree (~60%) and increased molecular weight of the protein were investigated by SDS-PAGE, indicating the compatibility of TP and TG treatment. According to physicomechanical findings, the TG2TP1 film exhibited the best characteristics. Tensile strength and water solubility properties were ameliorated by the TG treatment of TP-encapsulated films compared to the control film. TG and TP-loaded gelatin-zein composite film had better thermal stability than the control film. Moreover, the TP loading reduced the transparency value and improved the light-barrier properties of the film. The films showed significant antimicrobial activities against two food-borne bacteria, including Staphylococcus aureus BCTC13962 and Escherichia coli BCRC10675. The result obtained shows that the encapsulation of TP and TG treatment may be used to fabricate gelatin-zein composite film with controlled release of phenolic compounds for active packaging applications.

Enhancing the shelf life of chevon Seekh Kabab using chitosan edible film and Cinnamomum zeylanicum essential oil

Chevon Seekh Kabab is a popular meat product of India. However, due to high protein and moisture content it undergoes quick microbial spoilage and oxidative reactions leading to lower shelf life. The combination of chitosan edible film and cinnamon essential oil (CEO) was chosen to remediate this problem because of its antimicrobial and antioxidative effect. Control and chitosan edible film with CEO coated chevon Seekh Kabab samples were stored at 4 °C. The physicochemical (pH, TBARS, TVBN, moisture, colour), microbiological (APC, psychrophilic, coliform and Staphylococcal count) and sensory attributes were evaluated over a 30 days period. The maximum shelf life of 27 days was observed when 2% chitosan edible film with 0.3% CEO was coated over samples. A reduction in moisture, L* value, a* value and sensory scores along with an increase in pH, TVBN, TBARS, b* value and microbiological parameters were observed during the storage period. Reaction kinetics for the physicochemical and microbiological parameters was also established. The physicochemical, microbiological and sensory parameters were within prescribed limits till spoilage in the treated sample. This investigation may aid researchers working on scaling up of processing and preservation of Seekh Kabab.

Current and future interventions for improving poultry health and poultry food safety and security: A comprehensive review

Poultry is thriving across the globe. Chicken meat is the most preferred poultry worldwide, and its popularity is increasing. However, poultry also threatens human hygiene, especially as a fomite of infectious diseases caused by the major foodborne pathogens (Campylobacter, Salmonella, and Listeria). Preventing pathogenic bacterial biofilm is crucial in the chicken industry due to increasing food safety hazards caused by recurring contamination and the rapid degradation of meat, as well as the increased resistance of bacteria to cleaning and disinfection procedures commonly used in chicken processing plants. To address this, various innovative and promising strategies to combat bacterial resistance and biofilm are emerging to improve food safety and quality and extend shelf-life. In particular, natural compounds are attractive because of their potential antimicrobial activities. Natural compounds can also boost the immune system and improve poultry health and performance. In addition to phytochemicals, bacteriophages, nanoparticles, coatings, enzymes, and probiotics represent unique and environmentally friendly strategies in the poultry processing industry to prevent foodborne pathogens from reaching the consumer. Lactoferrin, bacteriocin, antimicrobial peptides, cell-free supernatants, and biosurfactants are also of considerable interest for their prospective application as natural antimicrobials for improving the safety of raw poultry meat. This review aims to describe the feasibility of these proposed strategies and provide an overview of recent published evidences to control microorganisms in the poultry industry, considering the human health, food safety, and economic aspects of poultry production.

Effect of Chitosan and Alginate-Based Edible Membranes with Oregano Essential Oil and Olive Oil in the Microbiological, Physicochemical and Organoleptic Characteristics of Mutton

Edible chitosan or alginate coatings and their combinations with oregano essential oil or olive oil, have been examined for their effect on the microbiological, physicochemical and organoleptic characteristics of mutton. The results indicated that these edible coatings can contribute to maintaining good quality characteristics and extending mutton shelf-life. The total mesophilic counts in mutton ranged from 3.48 to 8.00 log¹⁰ CFU/g, the total psychrophilic counts from 4.00 to 9.50 log¹⁰ CFU/g, the B. thermosphacta counts from 2.30 to 7.77 log¹⁰ CFU/g and the lactic acid bacteria counts from 2.00 to 5.85 log¹⁰ CFU/g. Chitosan coatings significantly (p < 0.05) reduced the total mesophilic, the total psychrophilic (1-2 log₁₀ cfu/g), the B. thermosphacta and the lactic acid bacteria counts in mutton. Alginate exhibited a lower L* value and a higher a* value and chroma compared with the control and chitosan lots. No significant differences were observed in the chemical composition of meat pieces among the experimental groups. Oregano oil positively affected the sensory attributes of meat. The most favourable combination, based on the microbiological counts, the organoleptic characteristics and the shelf-life extension of mutton, was that of chitosan with oregano essential oil.

Topical Application of Linezolid-Loaded Chitosan Nanoparticles for the Treatment of Eye Infections

Linezolid (LZ) loaded chitosan-nanoparticles (CSNPs) was developed by the ionic-gelation method using Tripolyphosphate-sodium as a crosslinker for topical application for the treatment of bacterial eye infections. Particles were characterized by Zeta-Sizer (Malvern Nano-series). TEM was used for structural morphology. Encapsulation and drug loading were estimated by measuring the unencapsulated drug. In-vitro drug release in STF (pH 7) was performed through a dialysis membrane. Storage stability of LZ-CSNPs was checked at 25 °C and 40 °C for six months. The antimicrobial potency of NPs was evaluated on different Gram-positive strains. Ocular irritation and pharmacokinetic studies were completed in rabbits. Ex-vivo transcorneal permeation of the drug was determined through the rabbit cornea. Ionic interaction among the oppositely charged functional groups of CS and TPP generated the CSNPs. The weight ratio at 3:1, wt/wt (CS/TPP) with 21.7 mg of LZ produced optimal NPs (213.7 nm with 0.387 of PDI and +23.1 mV of ZP) with 71% and 11.2% encapsulation and drug loading, respectively. Around 76.7% of LZ was released from LZ-AqS within 1 h, while 79.8% of LZ was released from CSNPs at 12 h and 90% at 24 h. The sustained drug release property of CSNPS was evaluated by applying kinetic models. The linearity in the release profile suggested that the release of LZ from CSNPs followed the Higuchi-Matrix model. LZ-CSNPs have shown 1.4 to 1.6-times improved antibacterial activity against the used bacterial strains. The LZ-CSNPs were "minimally-irritating" to rabbit eyes and exhibited 4.4-times increased transcorneal permeation of LZ than from LZ-AqS. Around 3-, 1.2- and 3.1-times improved T_max, C_max, and AUC_{0-24 h}, respectively were found for LZ-CSNPs during the ocular pharmacokinetic study. AqS has shown 3.1-times faster clearance of LZ. Conclusively, LZ-CSNPs could offer a better alternative for the prolonged delivery of LZ for the treatment of bacterial infections in the eyes.

Chitosan Edible Films and Coatings with Added Bioactive Compounds: Antibacterial and Antioxidant Properties and Their Application to Food Products: A Review

Chitosan is the deacetylated form of chitin regarded as one of the most abundant polymers and due to its properties, both chitosan alone or in combination with bioactive substances for the production of biodegradable films and coatings is gaining attention in terms of applications in the food industry. To enhance the antimicrobial and antioxidant properties of chitosan, a vast variety of plant extracts have been incorporated to meet consumer demands for more environmentally friendly and synthetic preservative-free foods. This review provides knowledge about the antioxidant and antibacterial properties of chitosan films and coatings enriched with natural extracts as well as their applications in various food products and the effects they had on them. In a nutshell, it has been demonstrated that chitosan can act as a coating or packaging material with excellent antimicrobial and antioxidant properties in addition to its biodegradability, biocompatibility, and non-toxicity. However, further research should be carried out to widen the applications of bioactive chitosan coatings to more foods and industries as well was their industrial scale-up, thus helping to minimize the use of plastic materials.

Chitosan edible coating incorporated with resveratrol and Satureja bachtiarica essential oil as natural active packaging: In vitro antibacterial and antioxidant properties, and its impact on the shelf life of fresh chicken fillet and growth of inoculated Escherichia coli O157:H7

The purpose of this study was to investigate the effects of chitosan coating containing resveratrol (RES) and Satureja bachtiarica essential oil (SEO) on the microbial quality, oxidative stability, and sensory properties of chicken meat as well as inoculated Escherichia coli O157:H7 during 12 day storage at 4 °C. The synergistic in vitro antioxidant effects between RES and SEO in chitosan coatings were observed. Moreover, chicken coated with chitosan solution containing RES 0.001% + SEO 2% indicated better results compared with the control group with the following scores (p≤0.05): Total viable count (6.11 log10 CFU/g), total psychrotrophic count (5.39 log10 CFU/g), Lactic acid bacteria (5.36 log10 CFU/g), pH (6.25), peroxide value (4.32 meq/kg lipid), thiobarbituric acid reactive substance (1.03 mg MDA/kg), sensory analysis (overall acceptability: 5.5), and inoculated E.coli O157:H7 (6.01 log10 CFU/g). The finding of the present study can contribute to the meat industry as a natural active packaging system.

Characteristics and Antibacterial Effect of Chitosan Coating Nanoemulsion Containing Zataria multiflora and Bunium persicum Essential Oils Against Listeria monocytogenes

Background: Nowadays, finding natural compounds with antimicrobial properties against pathogens is very important, especially for the food and drug industries. Objectives: The antibacterial activity of chitosan coatings nanoemulsion (NE) containing Zataria multiflora and Bunium persicum essential oils (EOs) was evaluated in a food model (chicken breast fillets) during 15 days of refrigerated storage. Methods: The chicken breast fillets were divided into seven groups: control, chitosan 2%, sonicated chitosan 2%, chitosan NE coating containing Z. muitiflora EO (ZMEO, 0.5%, and 1 %) and chitosan NE coating containing B. persicum EO (BPEO, 0.5%, and 1 %). Characteristics of chitosan NE coatings containing EOs were analyzed. Moreover, the antimicrobial activity of coatings against Listeria monocytogenes was investigated. Results: The results showed good properties of the NE coatings. The analysis of EOs revealed that the major components for ZMEO were carvacrol (51.55%) and thymol (25.49%). In addition, the main components of BPEO were p-cumic aldehyde (38.39%) and p-cymene (18.36%). All treatments exhibited antimicrobial properties; however, the best result was recorded for chitosan NE coating containing 1% ZMEO, which was the lowest amount of L. monocytogenes (7.61 Log CFU/g). Moreover, L. monocytogenes analysis for chitosan NE coating containing 1% BPEO samples was 7.73 Log CFU/g. Conclusions: Therefore, based on the results of this study, chitosan NE coating containing ZMEO and BPEO as natural preservatives can be recommended for meat products, especially chicken meats.

Effect of Antimicrobial and Antioxidant Rich Pomegranate Peel Based Edible Coatings on Quality and Functional Properties of Chicken Nuggets

The current study evaluated the effect of pomegranate peel-based edible coating on chicken nuggets in order to develop a functional and safe product, high in nutritional value. For this purpose, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and total phenolic content (TPC) assays were performed to check the potential antioxidant activity of chicken nuggets; microbial control, including total aerobic count and coliforms population, was performed for quality and safety purposes; and thiobarbituric acid reactive substances (TBARS) and peroxide value (POV) were performed to determine the oxidative stability of chicken nuggets. Different treatments were applied at different storage periods (0th, 7th, 14th and 21st day). The higher value of total aerobic count (5.09 ± 0.05 log CFU/g) and coliforms (3.91 ± 0.06 log CFU/g) were obtained for the uncoated samples, while the lower population was enumerated in the combination of sodium alginate (SA) and pomegranate peel powder (PPP). However, DPPH (64.65 ± 2.15%) and TPC (135.66 ± 3.07 GAE/100 g) values were higher in the coated chicken nuggets (SA (1.5%) and PPP (1.5%)) and lowest in the control samples. The higher value of TBARS (1.62 ± 0.03 MDA/kg) and POV (0.92 ± 0.03 meq peroxide/kg) were observed in the uncoated chicken nuggets. In the Hunter color system, L*, a*, and b* peak values were determined in the coated chicken nuggets with SA (1.5%) + PPP (1.5%) at the 21st day of storage. The uncoated chicken nuggets had different sensory characteristics (appearance, color, taste, texture, and overall acceptability) compared to the coated samples. Conclusively, coating based on the combination of SA (1.5%) and PPP (1.5%) increased the quality, safety, and nutritional properties of chicken nuggets.

Application of a Newly Developed Chitosan/Oleic Acid Edible Coating for Extending Shelf-Life of Fresh Pork

This study aimed at evaluating the applicability of a newly-developed chitosan/oleic acid edible coating for extending the shelf-life of fresh pork under aerobic-packaging conditions. Various coating formulations were used: 2% chitosan alone (CHI), 0.5% (v/v) oleic acid in 2% chitosan (CHI/0.5%OA) and 1% (v/v) oleic acid in 2% chitosan (CHI/1%OA) were prepared. For coating, fresh pork slices were fully immersed in the coating solutions for 30 s and dried naturally at 4 °C for 30 min. The coated samples were placed on trays, over-wrapped with plastic film, stored at 4 °C for 21 days, and were analyzed for shelf-life stability. Samples without coating were used as control. It was found that the aerobic bacteria and Pseudomonas spp. counts, and total volatile basic nitrogen (TVBN) content were almost two to three times lower in the CHI/OA-coated samples compared to the control after 21 days of storage (p < 0.05). The CHI/OA coating combination completely inhibited growth of E. coli, and protected the meat from discoloration after 21 days of storage. In particular, the addition of OA increased the concentration of volatiles associated with pleasant aromas. This study provides an application potential of chitosan/oleic acid edible coating in preservation of fresh pork to prolong the shelf-life and improve safety.

Convenient, nondestructive monitoring and sustained-release of ethephon/chitosan film for on-demand of fruit ripening

The microstructure changes (such as micro defects and free volume, etc.) is a deep factor that determines the sustained release behavior of polymer film. However, there are few reports exploring the micro defects of sustained-release materials. Herein, we develop a facile method to non-destructive monitoring and sustained-release ethylene within chitosan. The comprehensive means of positron annihilation lifetime spectroscopy, atomic force microscopy and Raman spectrums are performed together to study the microstructures change of ethylene sustained-release and its mechanism. When ethylene is in chitosan film, it shows good ripening performance and mechanical properties. The sustained-release ethylene improves its bioavailability and can control the fruit-ripening on-demand. More importantly, the microstructural changes of cavities have a significant impact on the sustained release of ethylene, due to the creation of cavities, the free volume of positrons undergoes a process of increasing from less to more and then gradually decreasing, reaching a maximum at 120 h. Furthermore, the ethephon/chitosan film could on-demand control the ripening time of mangoes and bananas. Therefore, this research presents a comprehensive means to study of microstructure change monitoring and controllable sustained release, and provides the possibility to solve the problem of on-demand ripening of fruit and reducing pesticide residue.

Combined Effect of Chitosan Coating and Laurel Essential Oil (Laurus nobilis) on the Microbiological, Chemical, and Sensory Attributes of Water Buffalo Meat

The combined effect of chitosan coating (CHI) and laurel essential oil (LEO) on the shelf-life extension of water buffalo meat stored under aerobic packaging conditions at 4 °C was investigated. Microbiological, physicochemical, and sensory attributes were monitored over an 18-day storage period. Microbiological data indicated that the (CHI) coating along with (LEO) was the most efficient among treatments in reducing populations of bacteria by 3.2 log cfu/g on day 6 of storage (p < 0.05). pH values of meat varied between 6.04 and 6.21, while thiobarbituric acid (TBA) values were equal to or less than 2.12 mg malondialdehyde/kg throughout storage. The colour parameter L* and a* values decreased, while b* values increased during storage (p < 0.05). Taste proved to be a more sensitive sensory attribute than odour. Based on sensory and microbiological data, product shelf life was approximately 5−6 days for control samples, 7−8 days for samples treated with (LEO), 12 days for samples treated with (CHI), and 13−14 days for samples treated with (CHI + LEO).

An overview of factors affecting the quality of beef meatballs: Processing and preservation

Beef meatball (BM) is a traditional delicious snack with rich nutrition and unique flavor, making it a preferred choice for most consumers. However, the quality of BM is easily affected by many factors, such as the processing, storage, and preservation, which limit the competitive positioning with respect to its market. Therefore, it is essential to pay attention to each step during the processing of BMs. Based on previous studies, this systematic review focuses on the effect of key processing factors (including raw materials and ingredients, beating, cooking methods, storage, and preservation) on the quality of BMs. Additionally, this study assessed the effect of each process factor on the physicochemical, sensory, nutritional, and safety attributes of BMs. Finally, the existing review will be beneficial in examining/describing the factors impacting the quality of BMs during processing, which would provide theoretical reference and scientific basis for the standardization and industrialization of BMs.

Analysis of Alternative Shelf Life-Extending Protocols and Their Effect on the Preservation of Seafood Products

Seafood is essential to a healthy and varied diet due to its highly nutritious characteristics. However, seafood products are highly perishable, which results in financial losses and quality concerns for consumers and the industry. Due to changes in consumer concerns, demand for healthy products has increased. New trends focusing on reducing synthetic preservatives require innovation and the application of additional or alternative strategies to extend the shelf life of this type of product. Currently, refrigeration and freezing storage are the most common methods for fish preservation. However, refrigeration alone cannot provide long shelf-life periods for fish, and freezing worsens sensorial characteristics and consumer interest. Therefore, the need to preserve seafood for long periods without exposing it to freezing temperatures exists. This review focuses on the application of other approaches to seafood products, such as biodegradable films and coating technology; superchilling; irradiation; high-pressure processing; hyperbaric storage; and biopreservation with lactic acid bacteria, bacteriocins, or bacteriophages. The efficiency of these techniques is discussed based on their impact on microbiological quality, sensorial degradation, and overall preservation of the product’s nutritional properties. Although these techniques are already known, their use in the industrial processing of seafood is not widespread. Thus, the novelty of this review is the aggregation of recent studies on shelf life extension approaches, which provide useful information for the selection of the most appropriate technology and procedures and industrial innovation. Despite the fact that all techniques inhibit or delay bacterial proliferation and product decay, an undesirable sensory impact may occur depending on the treatment conditions. Although no technique appears to replace refrigeration, the implementation of additional treatments in the seafood processing operation could reduce the need for freezing, extending the shelf life of fresh unfrozen products.

Development and Evaluation of Chitosan Nanoparticles for Ocular Delivery of Tedizolid Phosphate

This study investigates the development of topically applied non-invasive chitosan-nanoparticles (CSNPs) for ocular delivery of tedizolid phosphate (TZP) for the treatment of MRSA-related ocular and orbital infections. An ionic-gelation method was used to prepare TZP-encapsulated CSNPs using tripolyphosphate-sodium (TPP) as cross-linker. Particle characterization was performed by the DLS technique (Zeta-Sizer), structural morphology was observed by SEM. The drug encapsulation and loading were determined by the indirect method. In-vitro release was conducted through dialysis bags in simulated tear fluid (pH 7) with 0.25% Tween-80. Physicochemical characterizations were performed for ocular suitability of CSNPS. An antimicrobial assay was conducted on different strains of Gram-positive bacteria. Eye-irritation from CSNPs was checked in rabbits. Transcorneal flux and apparent permeability of TZP from CSNPs was estimated through excised rabbit cornea. Ionic interaction between the anionic and cationic functional groups of TPP and CS, respectively, resulted in the formation of CSNPs at varying weight ratios of CS/TPP with magnetic stirring (700 rpm) for 4 h. The CS/TPP weight ratio of 3.11:1 with 10 mg of TZP resulted in optimal-sized CSNPs (129.13 nm) with high encapsulation (82%) and better drug loading (7%). Release profiles indicated 82% of the drug was released from the TZP aqueous suspension (TZP-AqS) within 1 h, while it took 12 h from F2 to release 78% of the drug. Sustained release of TZP from F2 was confirmed by applying different release kinetics models. Linearity in the profile (suggested by Higuchi’s model) indicated the sustained release property CSNPs. F2 has shown significantly increased (p < 0.05) antibacterial activity against some Gram-positive strains including one MRSA strain (SA-6538). F2 exhibited a 2.4-fold increased transcorneal flux and apparent permeation of TZP as compared to TZP-AqS, indicating the better corneal retention. No sign or symptoms of discomfort in the rabbits’ eyes were noted during the irritation test with F2 and blank CSNPs, indicating the non-irritant property of the TZP-CSNPs. Thus, the TZP-loaded CSNPs have strong potential for topical use in the treatment of ocular MRSA infections and related inflammatory conditions.

Effects of Chitosan and Duck Fat-Based Emulsion Coatings on the Quality Characteristics of Chicken Meat during Storage

Chicken meat is a popular food commodity that is widely consumed worldwide. However, the shelf-life or quality maintenance of chicken meat is a major concern for industries because of spoilage by microbial growth. The aim of this study was to evaluate the effects of chitosan and duck fat-based emulsion coatings on the quality characteristics and microbial stability of chicken meat during refrigerated storage. The coated chicken meat samples were as follows: control (non-coated), DFC0 (coated with duck fat), DFC0.5 (coated with duck fat and 0.5% chitosan), DFC1 (coated with duck fat and 1% chitosan), DFC2 (coated with duck fat and 2% chitosan), and SOC2 (coated with soybean oil and 2% chitosan). The results showed that the apparent viscosity and coating rate were higher in DFC2 than in other groups. Physicochemical parameters (pH, color, and Warner-Bratzler shear force) were better in DFC2 than those in other groups during 15 days of storage. Moreover, DFC2 delayed lipid oxidation, protein deterioration, and growth of microorganisms during storage. These data suggest that chitosan-supplemented duck fat-based emulsion coating could be used to maintain the quality of raw chicken meat during refrigerated storage.

Antimicrobial Potential of Plastic Films Incorporated with Sage Extract on Chicken Meat

The function of packaging is crucial in the maintenance of fresh meat product quality. This study aimed to assess the efficiency of six films added with coatings 2379L/220 and 2379L/221 (containing sage extracts) to inhibit Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli, which showed that two of the six films had a significant effect. Additionally, the effects of the films on refrigerated skinless chicken breast meat were evaluated based on microbiological content, colour, weight loss, texture and pH. Four of the six films were examined could extend the storability of refrigerated chicken breast fillets for up to seven days. All six treated films improved the pH, colour stability, weight loss, and texture of the chicken fillets. Therefore, these findings suggested that the coatings containing sage extracts having different viscosities (2379L/220 and 2379L/221) were effective as antimicrobial adhesives in food packaging films and can be commercially applied in prolonging the storage of chicken breast meat without affecting their quality.

Edible coatings and films with incorporation of prebiotics -A review

Prebiotics are compounds naturally present in some foods or can be synthesized by microorganisms and enzymes. Among the benefits associated with prebiotic consumption are the modulation of the intestinal microbiota that increase the production of short chain fatty acids and prevent the development of some disorders such as colon cancer, irritable bowel syndrome, diabetes, obesity, among others. Traditionally, prebiotics have been used in diverse food formulations to enhance their healthy potential or to improve their technological and sensory properties. However, different alternatives for the production of prebiotic products are being explored, such as edible coatings and films. Therefore, this review aims to highlight recent research on edible coatings and films incorporated with different prebiotics, the concept of prebiotics, the general characteristics of these materials, and the main production methods, as well as presenting the perspectives of uses in the food industry. Current works describe that polyols and oligosaccharides are the most employed prebiotics, and depending on their structure and concentration, they can also act as film plasticizer or reinforcement agent. The use of prebiotic in the coating can also improve probiotic bacteria survival making it possible to obtain fruits and vegetables with synbiotic properties. The most common method of production is casting, suggesting that other technologies such as extrusion can be explored aiming industrial scale. The use of film and coating carried of prebiotic is an emerging technology and there are still several possibilities for study to enable its use in the food industry. This review will be useful to detect the current situation, identify problems, verify new features, future trends and support new investigations and investments.

Effect of chitosan coating incorporated with oregano or cinnamon essential oil on the bacterial diversity and shelf life of roast duck in modified atmosphere packaging

The present study aimed to investigate the effect of chitosan edible coating containing 0.15% oregano essential oil (OEO) or 0.60% cinnamon essential oil (CEO) on the quality characteristics and dynamic changes in the bacterial community of roast duck slices under modified atmosphere packaging (MAP, 30% CO₂/70% N₂) during 21 days of storage at 2 ± 2 °C. The results showed that the application of chitosan coating (CH) alone inhibited the growth of microorganisms and prevented lipid oxidation throughout storage. Moreover, the storage stability was further improved by including OEO or CEO, which lowered (P < 0.05) values for total viable count (TVC), Enterobacteriaceae, 2-thiobarbituric acid reactive substance (TBARS) and total volatile basic nitrogen (TVB-N). Based on the microbiological results, the shelf-life of CH-OEO and CH-CEO treated roast duck slices was prolonged by at least 7 days compared to that of the control. In addition, packaging types applied in this study played a major role in the bacterial community development. Notably, Vibrio spp. were the most predominant bacteria in all samples, when TVC values approached the shelf-life threshold, suggesting that this bacterium may be the main contributor to the spoilage of roast duck. The growth inhibition of Vibrio spp. in the CH-OEO and CH-CEO treatments during the early period of chilled storage might be the reason for the extension of the shelf life. Taken together, CH incorporated with OEO or CEO could be developed as prospective edible packaging materials to preserve roast duck meat.

The Effect of Electrospun Polycaprolactone Nonwovens Containing Chitosan and Propolis Extracts on Fresh Pork Packaged in Linear Low-Density Polyethylene Films

Fresh meat products are highly perishable and require optimal packaging conditions to maintain and potentially extend shelf-life. Recently, researchers have developed functional, active packaging systems that are capable of interacting with food products, package headspace, and/or the environment to enhance product shelf-life. Among these systems, antimicrobial/antioxidant active packaging has gained considerable interest for delaying/preventing microbial growth and deteriorative oxidation reactions. This study evaluated the effectiveness of active linear low-density polyethylene (LLDPE) films coated with a polycaprolactone/chitosan nonwoven (Film 1) or LLDPE films coated with a polycaprolactone/chitosan nonwoven fortified with Colombian propolis extract (Film 2). The active LLDPE films were evaluated for the preservation of fresh pork loin (longissimus dorsi) chops during refrigerated storage at 4 °C for up to 20 d. The meat samples were analyzed for pH, instrumental color, purge loss, thiobarbituric acid reactive substances (TBARS), and microbial stability (aerobic mesophilic and psychrophilic bacteria). The incorporation of the propolis-containing nonwoven layer provided antioxidant and antimicrobial properties to LLDPE film, as evidenced by improved color stability, no differences in lipid oxidation, and a delay of 4 d for the onset of bacteria growth of pork chops during the refrigerated storage period.

Chitosan Films Obtained from Brachystola magna (Girard) and Its Evaluation on Quality Attributes in Sausages during Storage

High molecular weight chitosan (≈322 kDa) was obtained from chitin isolated from Brachystola magna (Girard) to produced biodegradable films. Their physicochemical, mechanical and water vapor permeability (WVP) properties were compared against commercial chitosan films with different molecular weights. Brachystola magna chitosan films (CFBM) exhibited similar physicochemical and mechanical characteristics to those of commercial chitosans. The CFBM films presented lower WVP values (10.01 × 10⁻¹¹ g/m s Pa) than commercial chitosans films (from 16.06 × 10⁻¹¹ to 64.30 × 10⁻¹¹ g/m s Pa). Frankfurt-type sausages were covered with chitosan films and stored in refrigerated conditions (4 °C). Their quality attributes (color, weight loss, pH, moisture, texture and lipid oxidation) were evaluated at 0, 5, 10, 15 and 20 days. Sausages covered with CFMB films presented the lowest weight loss (from 1.24% to 2.38%). A higher increase in hardness (from 22.32 N to 30.63 N) was observed in sausages covered with CFMB films. Compared with other films and the control (uncovered sausages), CFMB films delay pH reduction. Moreover, this film presents the lower lipid oxidation level (0.10 malonaldehyde mg/sample kg). Thus, chitosan of B. magna could be a good alternative as packaging material for meat products with high-fat content.

Effects of nano-chitosan coatings incorporating with free /nano-encapsulated cumin (Cuminum cyminum L.) essential oil on quality characteristics of sardine fillet

Nowadays, adding biological compounds to food packaging is one of the types of active packaging. The aim of this study was to prepare a new degradable coating with free and nano-encapsulated Cumino cyminum L. essential oil (CCEO) with nanochitosan (Nch) base to evaluate the microbial, chemical and sensory properties of sardine fillet samples for 16 days at 4 °C. Nanoliposome using different soy lecithin ratios and cholesterol concentrations (60:0, 50:10, 40:20, and 30:30) and technique of thin-film hydration-sonication, were prepared with a range of 140-164 nm size. Encapsulation efficiency (EE) and distribution of nanoliposomes size were calculated 0.80-0.90 and 49.85-73.01% respectively. To coat sardine fillet samples, nanoliposomes with the lower size of droplet and higher EE percent were selected. The outcomes indicated that coating treatments can effectively inhibit microbial growth and chemical spoilage reflected at lower pH, peroxide value (PV) and thiobarbituric acid reactive substances (TBARs) (P < 0.05). In fact, the results of chemical and microbiological characteristics showed that the samples treated with nanocitosan/nano essential oil (NEO) showed the lowest value among other treatments during the experimental period, in the following, Nch-EO, Nch and control. pH, PV, TBARs, total viable counts (TVC), total pseudomonads count (TPC), and lactic acid bacteria (LAB) were 6.85, 0.03 (mg MDA/kg), 5.23 (mEq/kg), 3.67 (CFU/g), 3.47 (CFU/g), and 4.7 (CFU/g), respectively for Nch-NEO at the end of storage time. In addition, during the experimental period, the highest sensory properties were obtained for the Nch-NEO group. Encapsulation of CCEO reduces the rate of diffusion, thus increasing antimicrobial and antioxidant activity, as well as improving sensory properties. According to the results of this study, CCEO-encapsulated nanochitosan coatings can be used as a potent coating to increase sardine shelf life.

Application of essential oils as antimicrobial agents against spoilage and pathogenic microorganisms in meat products

Meat and meat products are perishable products that require the use additives to prevent the spoilage by foodborne microorganisms and pathogenic bacteria. Current trends for products without synthetic preservatives have led to the search for new sources of antimicrobial compounds. Essential oils (EOs), which has been used since ancient times, meet these goals since their effectiveness as antimicrobial agents in meat and meat products have been demonstrated. Cinnamon, clove, coriander, oregano, rosemary, sage, thyme, among others, have shown a greater potential to control and inhibit the growth of microorganisms. Although EOs are natural products, their quality must be evaluated before being used, allowing to grant the Generally Recognized as Safe (GRAS) classification. The bioactive compounds (BAC) present in their composition are linked to their activity, being the concentration and the quality of these compounds very important characteristics. Therefore, a single mechanism of action cannot be attributed to them. Extraction technique plays an important role, which has led to improve conventional techniques in favour of green emerging technologies that allow to preserve better target bioactive components, operating at lower temperatures and avoiding as much as possible the use of solvents, with more sustainable processing and reduced energy use and environmental pollution. Once extracted, these compounds display greater inhibition of gram-positive than gram-negative bacteria. Membrane disruption is the main mechanism of action involved. Their intense characteristics and the possible interaction with meat components make that their application combined with other EOs, encapsulated and being part of active film, increase their bioactivity without modifying the quality of the final product.

The Effects of Processing and Preservation Technologies on Meat Quality: Sensory and Nutritional Aspects

This review describes the effects of processing and preservation technologies on sensory and nutritional quality of meat products. Physical methods such as dry aging, dry curing, high pressure processing (HPP), conventional cooking, sous-vide cooking and 3D printing are discussed. Chemical and biochemical methods as fermentation, smoking, curing, marination, and reformulation are also reviewed. Their technical limitations, due to loss of sensory quality when nutritional value of these products is improved, are presented and discussed. There are several studies focused either on the nutritional or sensorial quality of the processed meat products, but more studies with an integration of the two aspects are necessary. Combination of different processing and preservation methods leads to better results of sensory quality; thus, further research in combinations of different techniques are necessary, such that the nutritional value of meat is not compromised.

Effects of Chitosan Coating with Green Tea Aqueous Extract on Lipid Oxidation and Microbial Growth in Pork Chops during Chilled Storage

Lipid oxidation and microbial growth are the major causes of meat quality deterioration. Natural ingredients in meat products have been proposed as a strategy to prevent quality deterioration during cold storage. This study aimed to assess the effects of added chitosan coating, alone and in combination with green tea water extract (GTWE), on the quality of pork chops during prolonged cold storage. For evaluating oxidative and antimicrobial stabilities, 72 fresh pork samples were subjected to four treatments (n = 18 per treatment): T0 (non-coated chops without GTWE); T1 (chitosan-coated chops without GTWE); T2 (chitosan-coated chops plus 0.1% of GTWE); and T3 (chitosan-coated chops plus 0.5% of GTWE). Pork samples were stored at 0 °C and subjected to physicochemical evaluation (pH, colour, and lipid oxidation) and microbiological analyses (mesophilic and pyschrotrophic counts) at 0, 5, 10, 15, 20 and 25 days of storage. GTWE presented high total phenolic content (> 500 mg gallic acid equivalents/g); the incorporation of chitosan coatings increased (p < 0.05) free radical scavenging activity (FRSA, >90% of inhibition) and microbial growth inhibition (>50% for all tested pathogens), depending on the concentration. Further, GTWE inclusion in pork samples (T2 and T3) reduced (p < 0.05) pH, lipid oxidation and microbial counts, as well as colour loss in meat and bone throughout storage. Chitosan coating with GTWE could be used as an additive for the preservation of pork meat products.

Preservation of traditional Chinese pork balls supplemented with essential oil microemulsion in a phase-change material package

BACKGROUND

In this study, we evaluated the combined effect of cinnamon essential oil (CEO) microemulsions, and a temperature buffering package using phase-change material (PCM) microcapsules on the physicochemical property, lipid oxidation, and bacterial load of traditional Chinese pork balls (shi zi tou) during temperature fluctuation storage for 9 days.

RESULTS

Transmission electron microscope characterization revealed that n-tetradecane microcapsules possessed a core-shell spherical shape with a size ranging from 300 to 600 nm. The use of n-tetradecane microcapsule packaging was found to maintain cold storage temperature efficiently. After 9 days of storage, the combination of CEO microemulsions with n-tetradecane microcapsules did not lead to changes in the color parameters of pork balls. At day 9, n-tetradecane microcapsules, used alone or in combination with CEO microemulsions, showed lower thiobarbituric acid reactive substances (TBARS) values than the control group, while their combination exhibited the lowest pH and 1,1-diphenyl-2-picrylhydrazyl (DPPH) values. Furthermore, the combination treatment retarded the growth of total plate count, lactic acid bacteria, Enterobacteriaceae, and Staphylococcus spp. after 4 and 9 days.

CONCLUSIONS

The combinations of CEO microemulsions and PCM microcapsules could extend the shelf-life of cooked pork products, suggesting a feasible strategy for meat preservation. © 2020 Society of Chemical Industry.

Chitin/chitosan derivatives and their interactions with microorganisms: a comprehensive review and future perspectives

Chitosan, obtained as a result of the deacetylation of chitin, one of the most important naturally occurring polymers, has antimicrobial properties against fungi, and bacteria. It is also useful in other fields, including: food, biomedicine, biotechnology, agriculture, and the pharmaceutical industries. A literature survey shows that its antimicrobial activity depends upon several factors such as: the pH, temperature, molecular weight, ability to chelate metals, degree of deacetylation, source of chitosan, and the type of microorganism involved. This review will focus on the in vitro and in vivo antimicrobial properties of chitosan and its derivatives, along with a discussion on its mechanism of action during the treatment of infectious animal diseases, as well as its importance in food safety. We conclude with a summary of the challenges associated with the uses of chitosan and its derivatives.