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1.
J Sci Food Agric ; 104(11): 6987-7001, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38619109

RESUMO

BACKGROUND: Conventional petroleum-based packaging films cause severe environmental problems. In the present study, bio-edible film was introduced as being safe to replace petroleum-based polymers. A food application for edible sachets and a composite edible film (EF) from marine algae, Gracilaria fisheri (GF) extract, were proposed. RESULTS: Carbohydrates were the most prevalent component in fresh GF fronds. Under neutral conditions comprising 90 °C for 40 min, the structure of the extract was determined by Fourier transform infrared to be a carrageenan-like polysaccharide. Glycerol was the best plasticizer for EF formation because it had the highest tensile strength (TS). The integration of gelatin into the algal composite film with gelatin (CFG) was validated to be significant. The best casting temperatures for 2 h were 70 and 100 °C among the four tested temperatures (25, 60, 70 and 100 °C). Temperatures did not result in any significant (P ≤ 0.05) differences in any character (color values, TS, water vapor permeability, oxygen transmission, thickness and water activity), except elongation at break. Visually, the CFG had a slightly yellow appearance. The best-to-worst order of film stability in the three tested solvents was oil, distilled water (DW) and ethanol. Its stability in ethanol (0-100%), temperature of DW (30-100 °C) and pH (3-7 in DW) demonstrated inverse relationships with the concentration or different conditions, except for pH 8-10 in DW. All treatments were significantly (P ≤ 0.05) different. CONCLUSION: The novel material made from polysaccharides from algae, G. fisheri, was used to improve EF. The edible sachet application is plausible from the EF. © 2024 Society of Chemical Industry.


Assuntos
Filmes Comestíveis , Embalagem de Alimentos , Gelatina , Gracilaria , Alga Marinha , Resistência à Tração , Gelatina/química , Embalagem de Alimentos/instrumentação , Alga Marinha/química , Gracilaria/química , Permeabilidade
2.
J Sci Food Agric ; 104(9): 5231-5243, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38415797

RESUMO

BACKGROUND: Vacuum packaging has the ability to reduce oxidative deterioration and microbial-induced spoilage of meat. However, in an oxygen-free environment, it can lead to the development of an unappealing purplish-red color and a decrease in the water-holding capacity of meat, thereby impacting the overall meat quality. Portulaca oleracea L. (POL) is a homology of medicine and food known for its exceptional antioxidant and antimicrobial properties. RESULTS: The aim of our present study was to investigate the antioxidant and antimicrobial ability of n-butanol phase extract of POL and the effect of POL extract incorporation on the quality (water-holding capacity, shear force, color, and texture) and physicochemical (pH, total volatile base nitrogen, and total viable counts) attributes of vacuum-packed seasoned steaks at 4 °C over a 15-day period. Results showed that the POL extract had excellent antioxidant and antimicrobial capacity. Furthermore, the addition of POL extract significantly inhibited protein oxidation and microbial growth of steaks (P < 0.05), and improved the water-holding capacity, color properties, and tenderness (P < 0.05). Moreover, there were no significant differences (P > 0.05) in the color, water-holding capacity, or tenderness between the 0.5 and 1 g kg-1 POL extract treatment groups compared to the sodium nitrite control group. CONCLUSION: These results indicate that POL extract had the potential to replace sodium nitrite due to its ability to hinder protein oxidation and microbial growth of vacuum-packed seasoned steaks, while enhancing the color, water-holding capacity, and tenderness of seasoned steaks. © 2024 Society of Chemical Industry.


Assuntos
Antioxidantes , Embalagem de Alimentos , Conservação de Alimentos , Armazenamento de Alimentos , Extratos Vegetais , Portulaca , Portulaca/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Embalagem de Alimentos/instrumentação , Vácuo , Animais , Conservação de Alimentos/métodos , Antioxidantes/farmacologia , Antioxidantes/química , Bovinos , Carne/análise , Carne/microbiologia , Cor , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química
3.
J Sci Food Agric ; 102(3): 976-983, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34302359

RESUMO

BACKGROUND: Although hydrogen gas (H2 ) has been widely used in industry and gradually used in medicine, it is less applied to agriculture, especially in modified atmosphere packing (MAP). RESULTS: During chicken egg storage, H2 MAP not only slowed down or delayed the reduction in antioxidant capacities, but also alleviated the deterioration of egg quality. The extent of micro-cracks in the eggshell was also negatively influenced by H2 , which might result in eggs being less vulnerable to microbes. The earlier results demonstrated that the H2 MAP-extended shelf life of chicken eggs might be caused by the responses of eggshell and re-establishment of redox homeostasis. According to the data collected from different provinces of China, cost-economics analysis further suggested that the increase in the extra cost caused by H2 was trivial compared with the original price of eggs. CONCLUSION: Together, H2 MAP can prolong the shelf life of chicken eggs with the prospect of wider application. © 2021 Society of Chemical Industry.


Assuntos
Ovos/análise , Conservação de Alimentos/métodos , Hidrogênio/farmacologia , Animais , Galinhas , Casca de Ovo/química , Casca de Ovo/efeitos dos fármacos , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos , Hidrogênio/química
4.
Lett Appl Microbiol ; 73(1): 39-45, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33742725

RESUMO

During storage of modified atmosphere packaged (MAP) meat, the initial microbiota grows to high cell numbers, resulting in perceptible spoilage after exceeding a specific threshold level. This study analyses, whether elevated oxygen consumption in the headspace of MA-packages would enable a prediction method for meat spoilage. We monitored the growth of single spoiling species inoculated on high-oxygen MAP beef and poultry, performed sensorial analysis and determined oxygen concentrations of the headspace via a non-invasive sensor spot technology. We detected microbial headspace oxygen consumption occurring prior to perceptible meat spoilage for certain species inoculated on beef steaks. However, headspace oxygen consumption and cell counts at the onset of spoilage were highly species-dependent, which resulted in a strong (Brochothrix thermosphacta) and moderate (Leuconostoc gelidum subspecies) decrease of the headspace oxygen content. No linear decrease of the headspace oxygen could be observed for Carnobacterium divergens and Carnobacterium maltaromaticum inoculated on poultry meat. We demonstrate the applicability of an incorporated oxygen sensor spot technology in MAP meat packages for detection of spoilage in individual packages prior to its perceptible onset. This enables individual package evaluation and sorting within retail, and consequently reduces meat disposal as waste.


Assuntos
Bactérias/metabolismo , Microbiologia de Alimentos/métodos , Embalagem de Alimentos/instrumentação , Carne/microbiologia , Oxigênio/análise , Animais , Atmosfera/química , Bovinos , Aves Domésticas
5.
Food Microbiol ; 99: 103822, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119107

RESUMO

This study assessed the evolution of spoilage microbiota in association with the changes in pH and concentrations of lactic and acetic acids in retail oxygen-free modified atmosphere (30:70 CO2/N2) packages (MAP) of minced free-range chicken meat during storage at 4 °C for 10 days. MAP retarded growth of spoilage lactic acid bacteria (LAB) below 6.5 log cfu/g and fully suppressed growth of pseudomonads, enterobacteria, enterococci, staphylococci and yeasts. Two distinct Latilactobacillus sakei strain biotypes were predominant and Leuconostoc carnosum, Carnobacterium divergens, Latilactobacillus fuchuensis and Weissella koreensis were subdominant at spoilage. The chicken meat pH ranged from 5.8 to 6.1. l-lactate (832 mg/100 g on day-0) decreased slightly on day-7. d-lactate remained constantly below 20 mg/100 g, whereas acetate (0-59 mg/100 g) increased 5-fold on day-7. All MAP samples developed off-odors on day-7 and a strong 'blown-pack' sulfur-type of spoilage on day-10. However, neither the predominant Lb. sakei nor other LAB or gram-negative isolates formed H2S in vitro, except for C. divergens.


Assuntos
Bactérias/isolamento & purificação , Embalagem de Alimentos/métodos , Carne/microbiologia , Microbiota , Animais , Atmosfera/análise , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Galinhas/microbiologia , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos
6.
Food Microbiol ; 98: 103686, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875196

RESUMO

This study aimed to achieve deeper insights into the microbiota composition and dynamic succession of the dry-cured black carp during storage using a high-throughput sequencing technique (HTS). The effect of lipid oxidation on microorganisms was also evaluated. Over 651 bacterial genera belonging to 37 phyla were identified. Firmicutes, Proteobacteria and Actinobacteria were the main bacterial phylum, some are highly associated with meat spoilage. Staphylococcus, Macrococcus and Acinetobacter were the most three microbial genera throughout the entire storage period (30 days). Between two different storage temperature, refrigeration at 4 °C could facilitate maintaining the microbial diversity, while 25 °C storage led to the formation of dominant microflora and the reduction of community diversity. Canonical correspondence analysis (CCA) showed that acid value (AV), malondialdehyde (MDA) and 4-hydroxy-2-hexenal (HHE) contents were three key environmental factors (oxidation products) affecting the profile of the microbiota. Staphylococcus presented a positive correlation with HHE content, while Macrococcus and Acinetobacter were negatively correlated with HHE content. These results could expand our knowledge on the effect of lipid oxidation on change of microbial distribution, it could also present an guideline to develop advanced storage methods for the vacuum packed dry-cured fish products.


Assuntos
Bactérias/isolamento & purificação , Produtos Pesqueiros/microbiologia , Lipídeos/química , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Carpas/microbiologia , Produtos Pesqueiros/análise , Microbiologia de Alimentos , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Armazenamento de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Refrigeração , Vácuo
7.
Food Microbiol ; 98: 103769, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875205

RESUMO

The transfer of blown pack spoilage causing Clostridium spores from the farm to the meat plant is of growing concern to the meat industry. This study investigated the environmental niches of these Clostridium spp., specifically Clostridium estertheticum and Clostridium gasigenes in the beef and sheep farm environments in New Zealand. Faecal, soil, grass, drinking water, puddle water and feed (fodder beet, hay, bailage and silage, where available) samples were collected on five beef and sheep farms during Winter and Spring in 2018, in North and South Island, respectively. Beef and sheep farm samples were tested for C. estertheticum and C. gasigenes using enrichment plus PCR, qPCR and direct plating. C. estertheticum was detected in bovine faecal (4%), soil (2-18%) and grass (0-12%) samples at concentration of up to 2.0 log10 cfu/g. C. gasigenes were found in 18-46% of faecal, 16-82% of soil, 12-44% of grass, 0-44.4% of drinking water and 0-58.3% of puddle water samples tested and the direct counts ranged from 2.4 log10 cfu/ml in puddle water to 3.4 log10 cfu/g in soil. C. estertheticum were detected by qPCR in sheep farms in ovine feces (2.3%), soil (2.3%) and fodder beet (10%). All other sample types (grass, drinking water, puddle water, baleage, hay, silage and fodder beet) were negative using direct and enrichment plus PCR methods. In contrast C. gasigenes was detected in of faecal (22.7-38.6%), soil (22.7-84.1%), grass (17.5-34.1%) drinking water (35.7-78.6%), puddle water (33.3-40%), hay baleage (57%), silage (2%) and fodder beet (10%) at concentrations of up to 3.7 log10 cfu/g/ml. It was concluded that C. estertheticum and C. gasigenes were common on beef and sheep farms with the latter having higher incidence and mean concentration.


Assuntos
Clostridium/crescimento & desenvolvimento , Microbiologia Ambiental , Carne/microbiologia , Matadouros , Criação de Animais Domésticos , Animais , Bovinos , Clostridium/classificação , Clostridium/genética , Clostridium/isolamento & purificação , Fazendas , Fezes/microbiologia , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Carne/análise , Nova Zelândia , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Ovinos
8.
Food Microbiol ; 94: 103648, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33279073

RESUMO

Shelf life of red meat is influenced by a number of intrinsic and extrinsic factors making its prediction challenging. Here we investigated the influence of geographically distant abattoir facilities and storage temperature relevant to commercial supply chain on the shelf lives of vacuum packaged (VP) beef and lamb meat. Samples of VP beef and lamb were analysed for surface pH, total viable counts, lactic acid bacterial counts, sensory properties, and associated bacterial community using Illumina MiSeq based 16S rRNA gene amplicon sequencing over a period of >200 days. The consistent 0.41 pH unit difference between beef and lamb was found to have a profound effect on bacterial community diversity and composition, bacterial growth rates and the rate of loss of sensory quality. Though different community structures were derived from different abattoir source, bacterial growth rate and rate of sensory quality deterioration were found to be comparable for individual meat type. The greatest variation in rates was found resulting from storage temperature and livestock species themselves. Our findings indicate that bacterial growth and sensory quality loss are essentially predictable when considering their temperature dependency, however for successful meat export validation of shelf life predictive models is required due to stochastic variation in abattoir seeded bacterial populations.


Assuntos
Bactérias/isolamento & purificação , Bovinos/microbiologia , Carne/microbiologia , Microbiota , Ovinos/microbiologia , Matadouros/estatística & dados numéricos , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Manipulação de Alimentos/instrumentação , Microbiologia de Alimentos , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Humanos , Paladar , Temperatura , Vácuo
9.
Food Microbiol ; 99: 103828, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119113

RESUMO

In this study, a composite film was prepared with bacterial cellulose (BC) of Gluconacetobacter xylinus and cell-free supernatant (CFS) of Enterococcus faecium TJUQ1, which was named BC-E. The optimum conditions for the preparation of the composite film with a minimal antibacterial activity were the soak of BC in 80 AU/mL CFS for 6 h. By scanning electron microscope observation, the surface network structure of BC-E was denser than that of BC. The tensile strength of BC and BC-E was 4.65 ± 0.88 MPa and 16.30 ± 0.92 MPa, the elongation at break of BC and BC-E was 3.33 ± 0.89% and 31.60 ± 1.15%, respectively, indicating the mechanical properties of BC-E were significantly higher than that of BC (P < 0.05). The swelling ratio of BC-E (456.67 ± 7.20%) was lower than that of BC (1377.78 ± 9.07%), demonstrating BC-E films presented better water resistance. BC-E films were soaked with 320 AU/mL CFS, and then used to pack the ground meat with 6.55 log10 CFU/g of Listeria monocytogenes. After 8 days of storage, the number of bacteria decreased by 3.16 log10 CFU/g. Similarly, total mesophilic bacterial levels in the ground meat decreased by 2.41 log10 CFU/g compared to control groups.


Assuntos
Antibacterianos/química , Celulose/química , Enterococcus faecium/metabolismo , Embalagem de Alimentos/instrumentação , Gluconacetobacter xylinus/metabolismo , Polímeros/química , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Celulose/metabolismo , Enterococcus faecium/química , Gluconacetobacter xylinus/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Carne/análise , Carne/microbiologia , Polímeros/farmacologia , Suínos , Resistência à Tração
10.
Food Microbiol ; 96: 103725, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33494898

RESUMO

Food packaging films were coated with polyvinyl acetate (PVA) containing different concentrations of citral or Litsea (L.) cubeba essential oil (EO). Antimicrobial contact trials in style of ISO22916 were performed. Citral coatings achieved bactericidal effects against Escherichia coli (2.1 log) and Staphylococcus aureus (4.3 log) at concentrations of 20%DM. L. cubeba inactivated more than 4 log cycles of both bacteria at a concentration of 20%DM. To determine the antimicrobial activity across the gas phase, a unique method for volatile agents was developed, adapting ISO22196. GC/MS measurements were performed to supplement microbiological tests in a model packaging system with a defined 220 ml headspace (HS). HS-equilibrium concentrations of 1.8 µg/mlAir were found for 20%DM 'citral-coatings, resulting in antimicrobial effects of 3.8 log against of E. coli. Saccharomyces cerevisiae (4.74 log) and Aspergillus niger (4.29 log) were more effectively inactivated by 3%DM and 5%DM coatings. In an application trial with strawberries, simulating a headspace packaging, growth inhibitory effects on the yeast and mold microbiota were found for the 20%DM coatings.


Assuntos
Monoterpenos Acíclicos/farmacologia , Antibacterianos/farmacologia , Litsea/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Monoterpenos Acíclicos/química , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Embalagem de Alimentos/instrumentação , Frutas/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos de Plantas/química , Polivinil/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
11.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466330

RESUMO

The effects of different storage conditions, light exposure, temperature and different commercially available cork stoppers on the phenolic, volatile and sensorial profile of Verdejo wines were studied. Two natural corks of different visual quality and a microgranulated cork stopper were investigated over one year at two different storage conditions. One simulating light exposure and temperature in retail outlets and the other simulating optimal cellar conditions (darkness and 12 °C). The wines stored under commercial conditions showed greater losses of total and free SO2 and higher levels of brown-yellowish tones, related to the oxidation of flavan-3-ols. Although these wines underwent a decrease in the total content of stilbenes, a significant increase in trans-piceid was observed. In addition, these wines suffered important changes in their volatile and sensory profile. Volatile compounds with fruity and floral aromas decreased significantly, while volatile compounds related to aged-type characters, as linalool oxides, vitispirane, TDN or furan derivatives increased. Wines stored in darkness at 12 °C underwent minor changes and their sensory profiles were similar to wine before bottling. The high-quality natural corks and microgranulated corks better preserved the quality of the white wines from a sensory point of view. These results showed that temperature and light exposure conditions (diffuse white LEDs and 24 ± 2 °C) in retail outlets considerably decrease the quality of bottled white wines and, consequently, their shelf life, due to the premature development of aged-type characters.


Assuntos
Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/normas , Odorantes/análise , Fenóis/análise , Controle de Qualidade , Compostos Orgânicos Voláteis/análise , Vinho/análise , Embalagem de Alimentos/métodos
12.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072199

RESUMO

Food contact materials (FCM) are defined as the objects and materials intended to come into direct or indirect contact with foodstuff, while food contact articles are defined as objects, being equipment, containers, packaging and various utensils which are clearly intended to be used for the manufacture, preparation, conservation, flow, transport or handling of foodstuffs [...].


Assuntos
Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/tendências , Tecnologia de Alimentos/métodos , Alimentos , Plásticos/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Medição de Risco , Segurança
13.
Molecules ; 26(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807750

RESUMO

The objective of this study was to develop an active banana starch film (BSF) incorporated with banana peel extract. We compared the film's properties with commercial wrap film (polyvinyl chloride; PVC). Moreover, a comparison of the quality of minced pork wrapped during refrigerated storage (7 days at ±4 °C) was also performed. The BSF with different concentrations of banana peel extract (0, 1, 3, and 5 (%, w/v)) showed low mechanical properties (tensile strength (TS): 4.43-31.20 MPa and elongation at break (EAB): 9.66-15.63%) and water vapor permeability (3.74-11.0 × 10-10 g mm/sm2 Pa). The BSF showed low film solubility (26-41%), but excellent barrier properties to UV light. The BSF had a thickness range of 0.030-0.047 mm, and color attributes were: L* = 49.6-51.1, a* = 0.21-0.43, b* = 1.26-1.49. The BSF incorporated with banana peel extracts 5 (%, w/v) showed the highest radical scavenging activity (97.9%) and inhibitory activity of E. coli O157: H7. The BSF showed some properties comparable to the commercial PVC wrap film. Changes in qualities of minced pork were determined for 7 days during storage at ±4 °C. It was found that thiobarbituric acid reactive substances (TBARS) of the sample wrapped with the BSF decreased compared to that wrapped with the PVC. The successful inhibition of lipid oxidation in the minced pork was possible with the BSF. The BSF incorporated with banana peel extract could maintain the quality of minced pork in terms of oxidation retardation.


Assuntos
Embalagem de Alimentos/instrumentação , Musa/química , Carne de Porco , Amido/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Materiais Biocompatíveis/química , Cor , Embalagem de Alimentos/métodos , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Luz , Teste de Materiais , Testes de Sensibilidade Microbiana , Permeabilidade , Extratos Vegetais/química , Carne de Porco/microbiologia , Temperatura , Água
14.
J Sci Food Agric ; 101(9): 3535-3540, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33345306

RESUMO

The strategy of adding hydrophobic compounds to bio-based films (usually based on hydrophilic matrices), forming films containing emulsions, is a technique that has been used to improve some physical properties (such as reducing water solubility and water vapor permeability) and / or to impart properties, such as antioxidant and antimicrobial effects by carrying hydrophobic active components that would otherwise be insoluble in hydrophilic matrices. Although Pickering emulsions have been reported as presenting greater stability when compared with surfactant-stabilized emulsions, little is known about the drying stability of Pickering emulsions (which is important for film applications). Anyway, several studies have indicated that Pickering emulsions are interesting systems to improve the water vapor barrier properties of bio-based films and coatings, and to act as carriers of active hydrophobic components. On the other hand, the tensile properties of those films are usually impaired by the presence of Pickering emulsions. The objective of this review is to present recent developments and future perspectives in bio-based films loaded with Pickering emulsions. © 2020 Society of Chemical Industry.


Assuntos
Emulsões/química , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/tendências , Tecnologia de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Vapor/análise
15.
J Sci Food Agric ; 101(12): 4925-4933, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33543471

RESUMO

BACKGROUND: Our living environment is being increasingly polluted by petroleum-based plastics and there is an increasing demand for biodegradable food packaging. In this study, the effect of various ultrahigh-pressure (UHP) treatments (0, 200 and 400 MPa) on the microstructure and thermal, barrier and mechanical properties of poly(lactic acid) (PLA)/ZnO nanocomposite films was studied. RESULTS: The film-forming solution was processed using UHP technology. The crystallinity, strength and stiffness of the composite film after UHP treatment increased. In addition, barrier property analysis showed that the UHP treatment significantly (P < 0.05) reduced the oxygen permeability and water vapor permeability (WVP) coefficient of the PLA/ZnO nanocomposite film. Furthermore, the WVP value of the film treated at 400 MPa (50 g kg-1 nano-ZnO content) was the lowest and reduced by 47.3% compared with that of pure PLA film. The improvement in these properties might be due to the interaction between nano-ZnO and PLA matrix promoted by UHP treatment. CONCLUSIONS: Therefore, the application of UHP technology on the film-forming solution could improve the crystallinity and functional properties of the nanocomposite film, and has great potential in the production of food packaging films with ideal functions. © 2021 Society of Chemical Industry.


Assuntos
Plásticos Biodegradáveis/química , Embalagem de Alimentos/instrumentação , Nanocompostos/química , Poliésteres/química , Óxido de Zinco/química , Permeabilidade , Vapor/análise , Temperatura , Resistência à Tração
16.
J Sci Food Agric ; 101(15): 6443-6451, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33990962

RESUMO

BACKGROUND: Different thermoplastic starch (TPS) films were prepared with or without the addition of microcrystalline cellulose (MCC) obtained via the melt-extrusion method, and then the hot-press method was used to produce environmentally friendly TPS-based film/paper composites to replace petroleum-based materials. RESULTS: The paper-plastic composites exhibited good interfacial adhesion from the scannign elctron microscopy images. It was seen that 5 wt.% MCC was added to reinforce the mechanical properties of TPS films, such that it also improved the barrier properties of MCC@TPS/paper composites and extended the path of water vapor through TPS films, which decreased the water vapor transmission rate of MCC@TPS/paper composites. TPS/paper composites and MCC@TPS/paper composites have better physical properties (i.e. smoothness, flexibility and folding resistance) than only paper. In particular, it was found that the water contact angle of MCC@TPS/paper composites and TPS/paper composites were higher than single-layer paper. Furthermore, MCC reinforced paper-plastic composites demonstrated good barrier properties which can meet the requirement of the need for lower water sensitive materials in the food packaging industry. CONCLUSION: Thermoplastic corn starch-based film/paper composites have good application properties as a potential source of bioplastic materials. © 2021 Society of Chemical Industry.


Assuntos
Celulose/química , Embalagem de Alimentos/instrumentação , Extratos Vegetais/química , Amido/química , Zea mays/química , Vapor , Temperatura , Resistência à Tração
17.
J Sci Food Agric ; 101(11): 4506-4513, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33449403

RESUMO

BACKGROUND: This work evaluated the performances of protein-based bioplastics obtained from black soldier fly (Hermetia illucens) prepupae. Protein films were synthesized by film casting, using both the whole proteins and their soluble fraction at pH = 10. The effects of glycerol as a plasticizer and of citric acid as a mild crosslinker on film properties were also evaluated. RESULTS: Films obtained using the soluble protein fraction were the strongest, as well as the most homogeneous and transparent ones. Protein mild crosslinking improved film tensile properties, especially in films obtained with the whole protein fraction. Non-crosslinked samples had a high affinity with water while crosslinking almost eliminated the ability of films to absorb water. All protein-based films proved to be effective barriers to red light (transmittance less than 2%). CONCLUSIONS: Bioplastics derived from black soldier fly prepupae may find applications in the agricultural sector (biodegradable pots, mulching films, utensils) and deserve to be tested for food and non-food packaging. © 2021 Society of Chemical Industry.


Assuntos
Plásticos Biodegradáveis/química , Dípteros/química , Proteínas de Insetos/química , Animais , Reagentes de Ligações Cruzadas/química , Embalagem de Alimentos/instrumentação , Larva , Pupa/química , Solubilidade
18.
J Sci Food Agric ; 101(5): 1800-1811, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32893889

RESUMO

BACKGROUND: Fish spoilage leads to an increase in the pH value of the fish. A colorimetric pH indicator can be used to monitor fish spoilage and has been exploited in intelligent packaging because of its simplicity, practicality and low cost. The aim of this study was to develop two pH-indicator films comprising starch (S), tara gum (TG), polyvinyl alcohol (PVA) and anthocyanins extracted from blueberry peel and the films were then used to monitor the freshness of tilapia fillets during storage at 25 and 4 °C. RESULTS: The ultraviolet-visible (UV-visible) spectra and color of anthocyanins changed within pH 2-10. Fourier-transform infrared spectroscopy, UV-visible spectrophotometry and scanning electron microscopy certified that blueberry peel extract (BPE) had been introduced into the S/PVA and TG/PVA matrices. Visual color changes in the films occurred at pH 2-8. A freshness application test was conducted in tilapia fillets stored at 4 and 25 °C, and visual color changes in the films were observed. The TG/PVA/BPE film had a greater color difference (ΔE) from pink and transparent to dark yellow at 25 °C and to dark purple at 4 °C than ΔE of S/PVA/BPE film, which sufficiently correlated with the change of total volatile base nitrogen (TVB-N) and total aerobic counts (TACs) of fillets. CONCLUSION: It can be concluded that the color changes of TG/PVA/BPE films were corresponded with TVB-N and TAC values of tilapia fillets, which presented great potential as a visual package label to monitor fish freshness at ambient and chilled temperatures. © 2020 Society of Chemical Industry.


Assuntos
Antocianinas/química , Mirtilos Azuis (Planta)/química , Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Embalagem de Alimentos/instrumentação , Polímeros/química , Animais , Cor , Qualidade dos Alimentos , Concentração de Íons de Hidrogênio , Polímeros/síntese química , Tilápia
19.
J Sci Food Agric ; 101(15): 6347-6354, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33969893

RESUMO

BACKGROUND: Vacuum package storage is commonly applied to reduce postharvest deterioration in minimally processed cassava roots. However, the influence of vacuum packaging conditions on root end-use quality is poorly understood. Hence, the effects of vacuum packaged storage at ambient, refrigerated and freezing temperatures on microflora, cassava tissue structure and starch extraction by wet milling were studied. RESULTS: Vacuum packaged storage temperature strongly affected cassava root quality. Minimal adverse effects were obtained with frozen storage. With refrigerated storage, there was negligible microbial growth but some disruption of the parenchyma cell wall structure suggestive of chilling injury. With ambient temperature storage, there was considerable Lactobacilli dominated fermentation. This caused substantial cell degradation, probably due to the production of extracellular cellulolytic and other cell wall degrading enzymes. A benefit of this cell wall breakdown was that it substantially improved starch extraction with wet milling from the stored cassava pieces; by 18% with pieces that had been ambient vacuum packaged and wet milled using a 2000 µm opening screen. However, ambient temperature storage resulted in some starch granule pitting due to the action of extracellular amylases from the fermenting microorganisms. CONCLUSION: The best vacuum packaging storage conditions for minimally processed cassava depends on application and cost. For short-term storage, refrigeration would be best for vegetable-type products. For several months storage, freezing is best. For wet milling applications, this could be combined with subsequent short-term ambient temperature storage as it improves starch extraction efficiency and could reduce distribution energy costs. © 2021 Society of Chemical Industry.


Assuntos
Embalagem de Alimentos/métodos , Manihot/química , Tubérculos/química , Amido/isolamento & purificação , Manipulação de Alimentos , Embalagem de Alimentos/economia , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos , Amido/análise , Temperatura , Vácuo
20.
J Sci Food Agric ; 101(3): 843-852, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32729127

RESUMO

BACKGROUND: Owing to fluctuations of international market prices and excess supply during peak harvesting seasons, farmers and traders often suffer from a low market price of sesame. Such a negative impact can be ameliorated by taking advantage of times with a better market price during the off season. This study aimed to investigate the impact of different storage containers on gravimetric properties and germination capacities of five different sesame varieties as well as their impact on Indian meal moth (Plodia interpunctella). RESULTS: There were differences among the types of storage containers in terms of moisture content, oil content, thousand seed weight, and germination capacity with the storage duration. However, in terms of bulk density, true density, and porosity, the results were consistent. On average, a few losses in thousand seed weight for varieties stored in Purdue Improved Crop Storage bags (1.7%), metal silos (2.4%), and GrainPro bags (3.4%) were observed during 12 months' storage compared with polypropylene bags (17%). The difference among sesame varieties in terms of weight loss and loss of webbing due to P. interpunctella varied with storage duration. On average, about 9.4% weight loss and 5.7% loss due to webbing was measured for seed stored in polypropylene bags due to the natural infestation of P. interpunctella. No pest was found in hermetic containers. CONCLUSION: In general, to fetch better market prices, the use of hermetic storage is more efficient to maintain the desired gravimetric properties and to prevent losses due to P. interpunctella infestation compared with the commonly used woven polypropylene bags. © 2020 Society of Chemical Industry.


Assuntos
Embalagem de Alimentos/instrumentação , Mariposas/fisiologia , Sementes/crescimento & desenvolvimento , Óleo de Gergelim/química , Sesamum/parasitologia , Animais , Etiópia , Armazenamento de Alimentos , Germinação , Sementes/química , Sementes/parasitologia , Sesamum/química , Sesamum/crescimento & desenvolvimento
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