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1.
J Photochem Photobiol B ; 222: 112263, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34339994

RESUMO

The biosynthesis of polyphenolic compounds in cabbage waste, outer green leaves of white head cabbage (Brassica oleracea L. var. capitata subvar. alba), was stimulated by postharvest irradiation with UVB lamps or sunlight. Both treatments boosted the content of kaempferol and quercetin glycosides, especially in the basal leaf zone, as determined by the HPLC analysis of leaf extracts and by a non-destructive optical sensor. The destructive analysis of samples irradiated by the sun for 6 days at the end of October 2015 in Skierniewice (Poland) showed an increase of leaf flavonols by 82% with respect to controls. The treatment by a broadband UVB fluorescent lamp, with irradiance of 0.38 W m-2 in the 290-315 nm range (and 0.59 W m-2 in the UVA region) for 12 h per day at 17 °C along with a white light of about 20 µmol m-2 s-1, produced a flavonols increase of 58% with respect to controls. The kinetics of flavonols accumulation in response to the photochemical treatments was monitored with the FLAV non-destructive index. The initial FLAV rate under the sun was proportional to the daily radiation doses with a better correlation for the sun global irradiance (R2 = 0.973), followed by the UVA (R2 = 0.965) and UVB (R2 = 0.899) irradiance. The sunlight turned out to be more efficient than the UVB lamp in increasing the flavonols level of waste leaves, because of a significant role played by UVA and visible solar radiation in the regulation of the flavonoid accumulation in cabbage. The FLAV index increase induced on the adaxial leaf side was accompanied by a lower but still significant FLAV increase on the unirradiated abaxial side, likely due to a systemic signaling by mean of the long-distance movement of macromolecules. Our present investigation provides useful data for the optimization of postharvest photochemical protocols of cabbage waste valorization. It can represent a novel and alternative tool of vegetable waste management for the recovery of beneficial phytochemicals.


Assuntos
Brassica/efeitos da radiação , Luz , Brassica/química , Brassica/metabolismo , Clorofila/química , Cromatografia Líquida de Alta Pressão , Flavonóis/análise , Flavonóis/metabolismo , Armazenamento de Alimentos , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espectrometria de Fluorescência , Raios Ultravioleta
2.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360903

RESUMO

Despite the fact that many studies have examined the effectiveness of different gaseous postharvest treatments applied at low temperature to maintain table grape quality, the use of ethanol vapor has hardly been investigated. Thus, this work has studied the effectiveness of ethanol vapor-generating sachets in the maintenance of It 681-30 table grape quality, a new cultivar, during storage at low temperature and after the shelf-life period at 20 °C. To this end, various quality assessments have been carried out and the effect of the ethanol treatment on the expression of different genes (phenylpropanoids, transcription factors, PRs, and aquaporins) was determined. The results indicated that the application of ethanol vapor reduced the total decay incidence, weight loss, and the rachis browning index in It 681-30 grapes stored at 0 °C and after the shelf-life period at 20 °C, as compared to non-treated samples. Moreover, the modulation of STS7 and the different PR genes analyzed seems to play a part in the molecular mechanisms activated to cope with fungal attacks during the postharvest of It 681-30 grapes, and particularly during the shelf-life period at 20 °C. Furthermore, the expression of aquaporin transcripts was activated in samples showing higher weight loss. Although further work is needed to elucidate the role of ethanol in table grape quality, the results obtained in this work provide new insight into the transcriptional regulation triggered by ethanol treatment.


Assuntos
Temperatura Baixa , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Gases/farmacologia , Vitis/efeitos dos fármacos , Aquaporinas/genética , Frutas/genética , Expressão Gênica/efeitos dos fármacos , Reação de Maillard/efeitos dos fármacos , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Transcrição Genética/efeitos dos fármacos , Vitis/genética , Volatilização
3.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde, LIS-bvsms | ID: lis-48281

RESUMO

A doença é causada por uma toxina que pode ser encontrada em determinados peixes como o tambaqui, o badejo e a arabaiana ou crustáceos (lagosta, lagostim, camarão).


Assuntos
Armazenamento de Alimentos
4.
Ultrason Sonochem ; 77: 105668, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34298307

RESUMO

To extend the shelf life and retain bioactive proteins in milk, this study utilized microfiltration (MF) combined with ultrasonication to treat skim milk and investigated its efficiency in removing bacteria and retaining bioactive proteins compared with HTST pasteurization and microfiltration alone. Results showed that microfiltration combined with ultrasonication at 1296 J/mL could completely remove the bacteria in skim milk. Ultrasonication further extended the shelf life (4 °C) of microfiltered skim milk, which could reach at least 40 days when MF was combined with ˃1296 J/mL ultrasonication. In addition, ELISA showed that HTST pasteurization significantly decreased the levels of IgG by ~30%, IgA by ~ 50%, IgM by ~60%, and lactoferrin by ~40%, whereas the activity of the enzymes lactoperoxidase and xanthine oxidase were also decreased by ~ 20%. Compared with HTST, MF alone or combined with ultrasonication retained these bioactive proteins to a larger degree. On the other hand, proteomics indicated both damage to casein micelle and fat globule structures in milk when ultrasonication at >1296 J/mL was applied, as shown by increases in caseins and milk fat globular proteins. Simultaneously, this ultrasound intensity also decreased levels of bioactive proteins, such as complement factors. Taken together, this study provided new insights that may help to implement this novel combination of non-thermal technologies for the dairy industry aimed at improving milk quality and functionality.


Assuntos
Filtração , Armazenamento de Alimentos , Leite/química , Proteínas/química , Sonicação , Animais , Temperatura
5.
Molecules ; 26(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198648

RESUMO

Apples are seasonal fruits, and thus after harvesting apples of optimal picking maturity, it is important to prepare them properly for storage and to ensure proper storage conditions in order to minimize changes in the chemical composition and commercial quality of the apples. We studied the quantitative composition of triterpenic compounds in the whole apple, apple peel and apple flesh samples before placing them in the controlled atmosphere (CA) chambers, and at the end of the experiment, 8 months later. HPLC analysis showed that highest total amount of triterpenic compounds (1.99 ± 0.01 mg g-1) was found in the whole apple samples of the 'Spartan' cultivar stored under variant VIII (O2-20%, CO2-3%, N2-77%) conditions. Meanwhile, the highest amount of triterpenic compounds (11.66 ± 0.72 mg g-1) was determined in the apple peel samples of the 'Auksis' cultivar stored under variant II (O2-5%, CO2-1%, N2-94%) conditions. In the apple peel samples of the 'Auksis' cultivar stored under variant I (O2-21%, CO2-0.03%, N2-78.97%) conditions, the amount of individual triterpenic compounds (ursolic, oleanolic, corosolic, and betulinic acids) significantly decreased compared with amount determined before the storage. Therefore, in the apple flesh samples determined triterpenic compounds are less stable during the storage under controlled atmosphere conditions compared with triterpenic compounds determined in the whole apple and apple peel samples.


Assuntos
Atmosfera , Cromatografia Líquida de Alta Pressão/métodos , Conservação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Frutas/química , Malus/química , Triterpenos/análise
6.
Int J Biol Macromol ; 185: 535-542, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34216656

RESUMO

Antimicrobial films based on polylactic acid (PLA) were developed by incorporating Thymus vulgaris essential oil (TV-EOs) with different concentrations of ethanolic extract of Mediterranean propolis (EEP) (5 wt% and 10 wt% based on PLA). The antimicrobial activities of EEP were performed by the agar disc diffusion method. The EEP exhibited high antimicrobial properties with inhibition zone diameter of 12.1 and 11.58 mm against Staphylococcus aureus and Penicillium sp., respectively. The addition of TV-EOs to films containing 5 and 10 wt% of EEP decrease the elastic modulus from 1292 MPa to 1084 MPa and 911.1 MPa to 794 MPa compared with films containing 5 and 10% of EEP alone, respectively. However, the elongation at break increased by 64% after the addition of TV-EOs to the film containing 10 wt% of EEP. Thermal stability of films improvement by the addition of TV-EOs and EEP. Antimicrobial activity of the films showed that films containing 10 wt% EEP inhibited the growth of Candida albicans and the combination of EEP and TV-EOs in the PLA matrix showed a synergistic effect against Escherichia coli. The developed PLA-based films with antimicrobial activity have a potential application in food packaging to increase the shelf life of packaged food.


Assuntos
Antibacterianos/farmacologia , Etanol/farmacologia , Óleos Voláteis/farmacologia , Poliésteres/química , Própole/química , Thymus (Planta)/química , Antibacterianos/química , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Etanol/química , Embalagem de Alimentos , Armazenamento de Alimentos , Óleos Voláteis/química , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Molecules ; 26(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204052

RESUMO

The aim of this study was to evaluate the effect of the packaging system type on the physical characteristics and microbial changes in ostrich meat during refrigerated storage. The applied packaging systems were vacuum packaging (VP) and modified atmosphere packaging (MAP) using two combinations of gases: MAP1 (40% O2/40% CO2/20% N2) and MAP2 (60% O2/30% CO2/10% N2). Eight meat samples were obtained in three replicates for all parameters, except for pH, for which six replicates were obtained from the M. ilifibularis (IF) muscle, and were stored in a refrigerator at 2 °C and analyzed at 0, 4, 8, 12 and 16 days for the effect of packaging methods on physical meat quality. The initial pH (5.99) decreased at the end of the storage time for MAP1 to 5.81, whereas VP was stable from day 0 to 12 and increased up to 6.08 on day 16. Regarding meat color, the L* value increased during storage for MAP1 and MAP2 from 36.99 to 40.75 and 41.60, respectively, whereas it declined for VP to 34.22. The same tendencies were reported for redness (a*) and yellowness (b*). Drip loss was the lowest in MAP1 and highest in VP. The lowest total viable bacteria counts were identified in VP, as compared to MAP1 and MAP2.


Assuntos
Bactérias/crescimento & desenvolvimento , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Carne/análise , Struthioniformes , Animais , Atmosfera , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Carne/microbiologia , Viabilidade Microbiana , Refrigeração , Tempo , Vácuo
8.
Nutrients ; 13(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199047

RESUMO

The gut microbiota has a profound effect on human health and is modulated by food and bioactive compounds. To study such interaction, in vitro batch fermentations are performed with fecal material, and some experimental designs may require that such fermentations be performed with previously frozen stools. Although it is known that freezing fecal material does not alter the composition of the microbial community in 16S rRNA gene amplicon and metagenomic sequencing studies, it is not known whether the microbial community in frozen samples could still be used for in vitro fermentations. To explore this, we undertook a pilot study in which in vitro fermentations were performed with fecal material from celiac, cow's milk allergic, obese, or lean children that was frozen (or not) with 20% glycerol. Before fermentation, the fecal material was incubated in a nutritious medium for 6 days, with the aim of giving the microbial community time to recover from the effects of freezing. An aliquot was taken daily from the stabilization vessel and used for the in vitro batch fermentation of lentils. The microbial community structure was significantly different between fresh and frozen samples, but the variation introduced by freezing a sample was always smaller than the variation among individuals, both before and after fermentation. Moreover, the potential functionality (as determined in silico by a genome-scaled metabolic reconstruction) did not differ significantly, possibly due to functional redundancy. The most affected genus was Bacteroides, a fiber degrader. In conclusion, if frozen fecal material is to be used for in vitro fermentation purposes, our preliminary analyses indicate that the functionality of microbial communities can be preserved after stabilization.


Assuntos
Fermentação , Congelamento , Microbioma Gastrointestinal , Animais , Bovinos , Criança , Fezes/microbiologia , Armazenamento de Alimentos , Microbioma Gastrointestinal/genética , Humanos , Masculino , Microbiota , Leite , Projetos Piloto , RNA Ribossômico 16S/genética
9.
Food Chem ; 362: 130114, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087708

RESUMO

Deficiency of vitamin-D is prevalent globally and can lead to negative health consequences. The fat-soluble nature of vitamin-D, coupled with its sensitivity to heat, light and oxygen limits its incorporation into foods. Mixed micelles (MM) have potential to enhance bioavailability of vitamin-D. This study explores the stability of MM to food processing regimes and their ability to protect vitamin-D. Subjecting MM to a range of shearing speeds (8,000-20,500 rpm) and to high pressure processing (600 MPa, 120sec) resulted in no change in MM size (4.1-4.5 nm). MM improved the retention of vitamin-D following exposure to UV-C light, near UV/visible light, and heat treatment. MM suspensions protected vitamin-D over a four week storage period at refrigeration or freezer conditions. Overall MM show potential to protect vitamin-D from degradation encountered in food processing and storage and may be beneficial as a mechanism to fortify foods with vitamin-D.


Assuntos
Colecalciferol/química , Indústria de Processamento de Alimentos/métodos , Micelas , Colecalciferol/análise , Armazenamento de Alimentos , Raios Ultravioleta
10.
Int J Biol Macromol ; 184: 463-475, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171252

RESUMO

Biofilm composition from fish myofibrillar protein (FMP) and chitosan solution (CS) incorporated with rosemary extract (RE) was developed and applied to monitor the freshness of fish fillets. The effects of different concentrations of RE as well as physical, mechanical, structural and functional properties of FMP/CS films were investigated. Films containing RE showed reduced water solubility and water vapor permeability and enhanced tensile strength and elongation at break. Results also showed good compatibility of the components and good dispersion of RE in the matrix. However, the content of RE (0.2%, v/v) added in the composite films produced aggregations and had negative effects on their film-forming properties. The antioxidant capacity of composite films was related to the level of RE and demonstrated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay. Chilled grass carp fillets wrapped with different films to evaluate the preservative effect. Results of thiobarbituric acid reactive substances, pH value, Free amino acid and total volatile basic nitrogen indicated that FMP/CS/RE composite film could protect the fish fillet well and inhibit the lipid oxidation. The developed FMP/CS/RE composite films possess the potential to be applied as edible films in the food packaging industry and food cold chain transportation.


Assuntos
Antioxidantes/farmacologia , Quitosana/química , Proteínas Musculares/química , Extratos Vegetais/farmacologia , Rosmarinus/química , Animais , Antioxidantes/química , Carpas , Filmes Comestíveis , Proteínas de Peixes/química , Embalagem de Alimentos , Armazenamento de Alimentos , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/química , Solubilidade , Vapor , Resistência à Tração
11.
Int J Biol Macromol ; 184: 429-437, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34166693

RESUMO

This study was carried out to characterize antioxidant activity, total phenolic content, and the phenolic and flavonoids profile of postbiotic of Pediococcus acidilactici and to evaluate the effects of postbiotics (10% and 50%) alone and in combination with chitosan coating (1%) on the microbial and chemical quality of chicken breast fillets during storage at 4 °C. Antioxidant activity and total phenolic content of the postbiotics were found to be 1291.02 ± 1.5 mg/L TEAC and 2336.11 ± 2.36 mg/L GAE, respectively. The most abundant phenolic was vanillic acid, followed by t-caffeic, gallic, and caftaric acids. The postbiotic-chitosan (50% + 1%) combination decreased L. monocytogenes and S. Typhimurium counts by 1.5 and 2.1 log10 CFU/g, respectively, compared to the control (P < 0.05). This combination decreased the total viable count (TVC), lactic acid bacteria (LAB), and psychrotrophic bacteria count compared to the control (P < 0.05). No differences were found in thiobarbituric acid (TBA) values among the samples during storage (P > 0.05). Postbiotic treatment did not significantly change the pH values and color properties of the breast fillets (P > 0.05). Postbiotic-chitosan combinations extended the shelf-life by up to 12 days compared to the control. In conclusion, the postbiotic-chitosan combination can be used to preserve and improve the microbial quality of chicken meat products.


Assuntos
Quitosana/farmacologia , Pediococcus acidilactici/química , Fenóis/farmacologia , Produtos Avícolas/análise , Animais , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Galinhas , Quitosana/química , Sinergismo Farmacológico , Armazenamento de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Fenóis/química , Produtos Avícolas/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento
12.
Int J Biol Macromol ; 184: 936-945, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34153361

RESUMO

The developed edible coating with curcumin facilitated iron functionalized cellulose nanofiber (f-CNF) reinforced chitosan (CS) were applied on kiwifruits for maintaining the quality during storage life. The f-CNF was fabricated via anchoring iron particles onto the surface of CNF as evident by FESEM, FETEM, and XRD analysis. The inclusion of f-CNF and curcumin as a component of edible coating can provide a synergistic effect in maintaining the quality of kiwifruits. The f-CNF (1.5 wt%) dispersed CS edible coating assisted by curcumin provided a lamellar and heterogonous surface morphology with a hazy appearance. The used edible coating materials were effective in reducing mass loss, firmness loss, respiration rate, and microbial count of the kiwifruits during storage life (10 days at 10 °C). Additionally, color, and physiological properties of kiwifruits can be modified by using the addressed edible coating materials.


Assuntos
Actinidia/química , Celulose/química , Quitosana/química , Curcumina/química , Filmes Comestíveis , Conservação de Alimentos , Armazenamento de Alimentos , Nanofibras , Difração de Raios X
13.
Int J Biol Macromol ; 183: 2100-2108, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34102235

RESUMO

Effect of edible coatings of gum Arabic, carrageenan and xanthan gum containing lemon grass essential oil 1% w/v on postharvest quality of strawberry was studied under refrigeration for a period of 12 days. Results showed all the three coatings maintained fruit quality parameters during storage compared to control. Among all the coatings, carrageenan coated fruits showed delayed weight loss (10.1 to 8%), decay percentage (78.42 to 14.29%), retained ascorbic acid (0.15 to 0.27 g kg-1), antioxidant activity (18.17 to 25.85%), firmness (9.07 to 12.43 N), L* (32.38 to 40.42), a* (16.08 to 17.22) and b* (27.36 to 33.54). Carrageenan gum also showed lowest cellulase activity (0.03 units h-1 mg protein-1), pectin methylesterase activity (1.13 A620 min-1 mg protein-1) and ß-galactosidase activity (0.51 µmol min-1 mg protein-1), while showed maximum reduction in polygalacturonase activity (0.07 units h-1 mg protein-1) at the end of storage. Carrageenan gum was found effective in retention of anthocyanins and phenolic compounds during storage. Coatings loaded with antimicrobial agent inhibited psychrophilic bacteria, yeast and mold growth. It is concluded that carrageenan gum could better retain strawberry quality up to 12 days under refrigeration.


Assuntos
Anti-Infecciosos/química , Carragenina/química , Filmes Comestíveis , Embalagem de Alimentos , Conservação de Alimentos , Fragaria/enzimologia , Frutas/enzimologia , Goma Arábica/química , Óleos Vegetais/química , Polissacarídeos Bacterianos/química , Antocianinas/metabolismo , Anti-Infecciosos/farmacologia , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Celulase/metabolismo , Cymbopogon , Microbiologia de Alimentos , Armazenamento de Alimentos , Fragaria/microbiologia , Frutas/microbiologia , Fenóis/química , Óleos Vegetais/isolamento & purificação , Óleos Vegetais/farmacologia , Poligalacturonase/metabolismo , Refrigeração , Fatores de Tempo , beta-Galactosidase/metabolismo
14.
Food Chem ; 362: 130218, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087713

RESUMO

In this research, three various Mw of chitosan (CS)-gallic acid (GA) conjugates were synthesized, characterized, and used for improvement of physicochemical stability of ß-carotene (BC) nanoemulsion (NE) by layer-by-layer technique. GA conjugation degrees were in the following order: HCS (125.6 mg/g) > MCS (102.3 mg/g) > LCS (74.6 mg/g) at GA:CS mass ratio of 0.5:1. Three varying Mw of CS-GA conjugates exhibited pronouncedly higher antioxidant abilities than native CS. For native CS, antioxidant abilities increased with the decrease of Mw. However, HCS-GA conjugate showed the highest antioxidant activity, due to the higher GA conjugation degrees and decreased intramolecular hydrogen bonds and crystallinity in HCS-GA conjugate. CS-GA conjugates substantially improved BC chemical stability in NE than CS and BC retentions were in the following order: HCS-GA (76.8%) > MCS-GA (68.3%) > LCS-GA (53.4%) after 30 days storage. The results obtained may provide some useful information for the applications of CS-GA conjugates for nutraceuticals stabilization in food systems.


Assuntos
Quitosana/química , Emulsões/química , Ácido Gálico/química , beta Caroteno/química , Antioxidantes/química , Suplementos Nutricionais , Armazenamento de Alimentos , Peso Molecular , Nanoestruturas/química , Eletricidade Estática
15.
Food Chem ; 362: 130221, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098436

RESUMO

Exopolysaccharides (EPS) were produced by four newly isolated lactic acid bacteria strains, then further extracted, separated and characterised under standardised conditions. Using a sucrose carbon source, these LAB strains belonging to Weissella confusa/cibaria produced EPS with a dextran high molecular weight fraction. The obtained yields of EPS ranged from 3.2 g/L to 47.1 g/L and outstandingly high yields were obtained using Weissella confusa/cibaria 3MI3 isolated from spontaneous spelt sourdough. After purification the influence of EPS-dextran of molar mass 3,244,000 g/mol on resistant starch formation in wheat starch pastes and pasted samples after temperature-cycled storage was examined. Size exclusion chromatography with post-column derivatisation revealed that a 1.5% share of EPS dextran limited formation of high molar mass resistant starch in starch pastes during storage. This work provides new insight on hindering resistant starch formation by using EPS, which could be efficiently produced in sourdough, thus improving the properties of sourdough bread.


Assuntos
Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Amido/química , Triticum , Weissella/metabolismo , Pão/análise , Fracionamento Químico , Fermentação , Armazenamento de Alimentos , Amido Resistente , Sacarose/metabolismo , Triticum/química , Triticum/microbiologia , Weissella/química , Weissella/isolamento & purificação
16.
Food Chem ; 362: 130076, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090048

RESUMO

The internal blue discoloration of radish roots (Raphanus sativus) during storage affects their quality. We here performed transcriptome and metabolome profiling to investigate the mechanisms underlying the bluing of radish roots during storage. On comparing white radish (WR) and blue radish (BR), we identified 14,171 differentially expressed genes (upregulated: 7,383, downregulated: 6,788) and 145 differentially accumulated metabolites (upregulated: 117, downregulated: 28). Functional annotation analysis and metabolome profiling revealed that the blue discoloration of radish roots was promoted by high content of glucosinolates, oxidation system (ROS, CAT, POD) or low reduction system (GSH, GPX, APX, GST, ASA). Our results provide new insights into the underlying metabolic causes of the blue discoloration of radish roots and report candidate genes and metabolites involved in blue compound biosynthesis.


Assuntos
Metaboloma , Raízes de Plantas/metabolismo , Raphanus/genética , Raphanus/metabolismo , Transcriptoma , Armazenamento de Alimentos , Regulação da Expressão Gênica de Plantas , Glucosinolatos/metabolismo , Oxirredução , Pigmentação
17.
Food Chem ; 362: 130151, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087707

RESUMO

Hydrogels based on alginate and methylcellulose were developed as a colorimetric indicator for monitoring minced pork spoilage. The hydrogel was fabricated by an external gelation method using Ca2+ as the crosslinking agent. The pH-sensitive dye bromothymol blue was incorporated into the hydrogel to act as an indicator. The hydrogel's swelling index increased with an increasing ratio of methylcellulose, suggesting that the water uptake capacity is tunable by the polymer composition. The hydrogel's compression strength is directly proportional to the alginate content. The hydrogel indicator demonstrated a color change from orange to yellow (day 6) upon detecting total volatile basic nitrogen (TVB-N) built up in the package during minced pork storage at 4 °C, and the results showed a positive correlation between the color change, TVB-N and pH change of minced pork. This result demonstrated the potential application of the hydrogel as a spoilage indicator in intelligent packaging.


Assuntos
Amônia/análise , Colorimetria/métodos , Análise de Alimentos/métodos , Hidrogéis/química , Carne de Porco/análise , Alginatos/química , Animais , Azul de Bromotimol/química , Cálcio/química , Cor , Colorimetria/instrumentação , Análise de Alimentos/instrumentação , Qualidade dos Alimentos , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Metilcelulose/química , Nitrogênio/análise , Suínos , Água/química
18.
Food Chem ; 362: 130199, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091167

RESUMO

Crocins in commercial liquid saffron extracts (Saffr'activ®) were identified using high-performance liquid chromatography (HPLC) with a diode array detector (DAD) and mass spectrometry (MS). The impact of storage on the qualities of the saffron extract were studied with HPLC-DAD-MS by exposing trans-4-GG crocin to environmental factors. Light and temperature induced degradation after only one week. Trans-4-GG crocin was totally hydrolyzed when stored at 60 °C and exposed to light. A quick and reliable method using HPLC-DAD was then developed to improve quantification of crocins in commercial liquid saffron extracts. An internal standard quantification method that uses a response factor, corrected with the molecular weight of each crocin, improved results for old saffron extracts.


Assuntos
Carotenoides/análise , Cromatografia Líquida de Alta Pressão/métodos , Crocus/química , Espectrometria de Massas/métodos , Extratos Vegetais/análise , Ar , Carotenoides/química , Análise de Alimentos/métodos , Armazenamento de Alimentos/métodos , Luz , Extratos Vegetais/química , Vitamina A/análogos & derivados , Vitamina A/química
19.
Food Chem ; 362: 130101, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091173

RESUMO

To enhance the stability of anthocyanin, an amphiphilic peptide C6 with tryptophan amino acid was used to co-assemble with anthocyanin C3G. The characterization, stabilities, and antioxidant activity of peptide-anthocyanin (C6-C3G) nanocomposites (70.82 ± 12.41 nm) were investigated. To illustrate the interaction between peptide and anthocyanin, circular dichroism spectroscopy and fluorescence quenching method were used. Here, the peptide C6 switches from random coil structure to ß-sheet structure and the fluorescence of tryptophan amino acid in peptide quenched during the intermolecular interaction between them, which was further confirmed a static quenching. The nanocomposites significantly enhance the stabilities of anthocyanin to different alkaline conditions, high temperature of 80 °C, long time storage, and various concentration of Cu2+ ion. In addition, it maintained the excellent intrinsic capacity of anthocyanin to scavenge free radicals. The approach of using an amphiphilic peptide to enhance the stabilities of anthocyanin presents a high potential to expand its application.


Assuntos
Antocianinas/química , Peptídeos/química , Antioxidantes/química , Dicroísmo Circular , Fluorescência , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Nanocompostos/química , Conformação Proteica em Folha beta , Temperatura , Triptofano/química
20.
J Food Sci ; 86(7): 3001-3013, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34146415

RESUMO

Softening is one of the main factors affecting market value and consumer preferences for jujubes, and it was closely related to the modification and depolymerization of pectin. Changes in characteristics of three pectins (water-soluble pectin (WSP), sodium carbonate-soluble pectin (SSP) and chelate-soluble pectin (CSP)), including their contents, degree of methylesterification (DM), neutral sugar compositions, the molecular weight (Mw ) distributions and nanostructures, from two jujube fruits cv Dongzao (DZ) and Jinsixiaozao (JS) during cold storage were assessed. The results showed that variation in pectin characteristics during cold storage was similar between DZ and JS. The reduction of firmness corresponded to a conversion of water-insoluble pectin to WSP during cold storage. DM of WSP presented an increase trend in the late storage. Rhamnose (Rha), arabinose (Ara) and glucose (Glc) were the crucial compositions in three pectins, and most neutral sugar compositions in three pectins first increased and then decreased during cold storage. Changes in the ratio of (galactose (Gal)+Ara)/Rha and Ara/Gal represented that the branch chains of rhamnogalacturonan-I in three pectins depolymerized after storage. The high Mw in WSP and SSP of jujubes were solubilized and extensively depolymerized into pectin with lower Mw after storage. AFM images showed an increase in short chains and branch structures of three pectins after storage. Overall, three pectins in DZ and JS depolymerized and solubilized during cold storage. WSP and SSP were more contributed to the softening of jujubes compared to CSP, and they played the critical role for regulating the softening of jujube fruits during cold storage. PRACTICAL APPLICATION: Softening is one of the main factors affecting market value and consumer preferences for jujubes, and it was closely related to the modification and depolymerization of pectin. Changes in characteristics of three pectins (WSP, SSP, CSP), including their contents, degree of methylesterification, neutral sugar compositions, the molecular weight distributions and nanostructures, from two jujube fruits cv Dongzao (DZ) and Jinsixiaozao (JS) during cold storage were assessed. Three pectins in DZ and JS depolymerized and solubilized during cold storage. WSP and SSP were more contributed to the softening of jujubes compared to CSP, and they played the critical role for regulating the softening of jujube fruits during cold storage. This study would elucidate the mechanism of jujube softening and help to regulate the postharvest quality during cold storage.


Assuntos
Frutas/química , Pectinas/química , Ziziphus/química , Parede Celular/química , Temperatura Baixa , Armazenamento de Alimentos , Frutas/classificação , Peso Molecular , Ziziphus/classificação
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