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1.
J Food Sci ; 89(7): 4359-4371, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38847748

RESUMO

Hydrocolloids are widely used in meat products as common food additives. However, research has indicated that excessive consumption of these hydrocolloids may have potential health implications. Currently, consumers mainly rely on sensory evaluation to identify hydrocolloid adulteration in meat products. Although many studies on quantitative detection of hydrocolloids have been conducted by biochemical methods in laboratory environments, there is currently a lack of effective tools for consumers and regulators to obtain real-time and reliable information on hydrocolloid adulteration. To address this challenge, a smartphone-based computer vision method was developed to quantitatively detect carrageenan adulteration in beef in this work. Specifically, Swin Transformer models, along with pre-training and fine-tuning techniques, were used to successfully automate the classification of beef into nine different levels of carrageenan adulteration, ranging from 0% to 20%. Among the tested models, Swin-Tiny (Swin-T) achieved the highest trade-off performance, with a Top-1 accuracy of 0.997, a detection speed of 3.2 ms, and a model size of 103.45 Mb. Compared to computer vision, the electrochemical impedance spectroscopy achieved a lower accuracy of 0.792 and required a constant temperature environment and a waiting time of around 30 min for data stabilization. In addition, Swin-T model was also capable of distinguishing between different types of hydrocolloids with a Top-1 accuracy of 0.975. This study provides consumers and regulators with a valuable tool to obtain real-time quantitative information about meat adulteration anytime, anywhere. PRACTICAL APPLICATION: This research provides a practical solution for regulators and consumers to non-destructively and quantitatively detect the content and type of hydrocolloids in beef in real-time using smartphones. This innovation has the potential to significantly reduce the costs associated with meat quality testing, such as the use of chemical reagents and expensive instruments.


Assuntos
Carragenina , Coloides , Contaminação de Alimentos , Smartphone , Contaminação de Alimentos/análise , Coloides/química , Animais , Bovinos , Carragenina/análise , Carragenina/química , Produtos da Carne/análise , Aditivos Alimentares/análise , Carne Vermelha/análise , Carne/análise
2.
Chem Biodivers ; 20(9): e202300349, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37574856

RESUMO

The current study aimed to evaluate the anti-inflammatory activity of Dicliptera bupleuroides Nees aerial parts methanol extract and its different fractions namely hexane, chloroform, ethyl acetate and butanol in vitro using cyclooxygenase inhibitory assay (COX-2). In vivo anti-inflammatory evaluation was performed using carrageenan and formalin induced inflammation in rat models followed by molecular docking. High performance liquid chromatography (HPLC) and gas chromatography coupled with mass chromatography (GC/MS) analyses were used for chemical analyses of the tested samples. The tested samples showed significant inhibition in COX-2 inhibitory assay where methanol extract (DBM) showed the highest inhibitory potential at 100 µg/mL estimated by 67.86 %. At a dose of 400 mg/kg, all of the examined samples showed pronounced results in carrageenan induced acute inflammation in rat model at 4th h interval with DBM showed the highest efficiency displaying 65.32 % inhibition as compared to the untreated rats. Formalin model was employed for seven days and DBM exhibited 65.33 % and 69.39 % inhibition at 200 and 400 mg/kg, respectively approaching that of the standard on the 7th day. HPLC revealed the presence of caffeic acid, gallic acid and sinapic acid, quercetin and myricetin in DBM. GC/MS analysis of its hexane fraction revealed the presence of 16 compounds belonging mainly to fatty acids and sterols that account for 85.26 % of the total detected compounds. Molecular docking showed that hexadecanoic acid followed by decanedioic acid and isopropyl myristate showed the best fitting within cyclooxygenase-II (COX-II) while nonacosane followed by hexatriacontane and isopropyl myristate revealed the most pronounced fitting within the 5-lipoxygenase (5-LOX) active sites. Absorption, metabolism, distribution and excretion and toxicity prediction (ADMET/ TOPKAT) concluded that most of the detected compounds showed reasonable pharmacokinetic, pharmacodynamic and toxicity properties that could be further modified to be more suitable for incorporation in pharmaceutical dosage forms combating inflammation and its undesirable consequences.


Assuntos
Hexanos , Extratos Vegetais , Ratos , Animais , Carragenina/análise , Carragenina/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Metanol/química , Simulação de Acoplamento Molecular , Prostaglandina-Endoperóxido Sintases/análise , Prostaglandina-Endoperóxido Sintases/uso terapêutico , Formaldeído/análise , Formaldeído/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Componentes Aéreos da Planta/química
3.
Food Sci Technol Int ; 29(4): 287-298, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35043718

RESUMO

The loss of fresh produce along the supply chain represents a significant contributor to environmental and economic burden. Although technological advances in distribution and storage have provided a means to reduce the loss of fresh produce, in resource-limited settings, these technologies may not be available. One attractive approach to help address this limitation is to use edible coatings to protect fresh produce from biotic and abiotic factors that cause food deterioration. Here, we developed edible coatings from materials that are cheap and easy to prepare: maize starch, κ-carrageenan, and agar as the matrix; glycerol as the plasticizer; and Lactobacillus plantarum TPB21.12 as the active ingredient. Using fresh cut apples as a model substrate, we found that maize starch coating retained color, agar coating delayed browning, and κ-carrageenan coating decreased mass shrinkage of the fresh cut apples. L. plantarum TPB21.12 remained viable in the edible coating suspensions during storage and was active against Escherichia coli TPB21.8, a model bacterium for biotic factor that causes food spoilage. The simplicity of the edible coating formulation and preparation method offers an attractive approach for applications to help protect fresh produce from deterioration and reduce food loss and waste generation.


Assuntos
Filmes Comestíveis , Lactobacillales , Malus , Humanos , Malus/química , Frutas/química , Conservação de Alimentos , Carragenina/análise , Ágar/análise , Polissacarídeos/análise , Amido/química
4.
Crit Rev Food Sci Nutr ; 63(13): 1901-1929, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34463176

RESUMO

Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds.Key teaching pointsStructure and biological functions of main seaweed polysaccharides.Emerging extraction methods for sulfate polysaccharides.Chemical modification of seaweeds polysaccharides.Potential industrial applications of seaweed polysaccharides.Biological activities, knowledge gaps and future trends of seaweed polysaccharides.


Assuntos
Produtos Biológicos , Polissacarídeos , Alga Marinha , Alga Marinha/química , Polissacarídeos/análise , Polissacarídeos/química , Alimento Funcional , Alginatos/análise , Alginatos/química , Ágar/análise , Ágar/química , Carragenina/análise , Carragenina/química , Fracionamento Químico/métodos , Estrutura Molecular
5.
Ethiop J Health Sci ; 32(4): 817-822, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35950076

RESUMO

Background: The objective of this study was to evaluate the anti-inflammatory activities and phytochemical composition of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv. Methods: The powdered leaves of Boscia coriacea Graells and Uvaria leptocladon Oliv were extracted by maceration and soxhlet extraction methods. Anti-inflammatory activity of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv were evaluated using carrageenan-induced paw edema model. Standard methods were used for analysis of phytochemical composition of the leaves extracts of Boscia coriacea Graells and Uvaria leptocladon Oliv. Data analysis was done using one way analysis of variance. Results: U. leptocladon Oliv (200 mg/kg) and B. coriacea Graells (200 mg/kg) showed percent inhibition on mice paw edema of 86% and 75% after six hours of carrageenan injection, respectively. The ethanol fraction (100 mg/kg) of U. leptocladon Oliv showed the highest anti-inflammatory effect after six hours of carrageenan injection. The phytochemical analysis of the leaves extracts of B. coriacea and U. leptocladon revealed the presence of tannins, alkaloids, cardiac glycoside, flavonoids, phenols, quinones, and saponins. Conclusion: The crude leaves extracts of B. coriacea Graells and U. leptocladon Oliv contain phytochemicals with anti-inflammatory activities.


Assuntos
Uvaria , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Carragenina/efeitos adversos , Carragenina/análise , Edema/tratamento farmacológico , Camundongos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Uvaria/química
6.
Biomolecules ; 11(6)2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072325

RESUMO

The use of seaweeds as additives in animal nutrition may be a valid option to traditional feed as they represent a rich source of minerals, carbohydrates and antioxidants. The aim of this study was to analyze the chemical composition and in vitro antioxidant capacity of two tropical eucheumatoids, Kappaphycus alvarezii and Kappaphycus striatus, in Malaysian wild offshore waters. The chemical analysis was performed via inductively coupled plasma-optical emission spectroscopy for evaluating the concentration of toxic (Cd, Pb, Hg, As) and essential elements (Mn, Fe, Cu, Ni, Zn, Se); NMR spectroscopy was used for carrageenans investigation. Furthermore, the soluble and fat-soluble antioxidant capacities were determined by FRAP, DPPH and ABTS assays. The chemical analysis revealed a higher content of trace elements in K. alvarezii as compared to K. striatus, and both exhibited a high mineral content. No significant differences in metal concentrations were found between the two species. Both samples showed a mixture of prevailing κ- and t-carrageenans. Finally, the levels of soluble and fat-soluble antioxidants in K. alvarezii were significantly higher than in K. striatus. Our findings suggest that K. alvarezii could be used as a potential feed additive because of its favorable chemical and nutritional features.


Assuntos
Antioxidantes/análise , Carragenina/análise , Rodófitas/química , Alga Marinha/química , Oligoelementos/análise
7.
Mar Drugs ; 19(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069393

RESUMO

Ultrasound-assisted water extraction was optimized to recover gelling biopolymers and antioxidant compounds from Mastocarpus stellatus. A set of experiments following a Box-Behnken design was proposed to study the influence of extraction time, solid liquid ratio, and ultrasound amplitude on the yield, sulfate content, and thermo-rheological properties (viscoelasticity and gelling temperature) of the carrageenan fraction, as well as the composition (protein and phenolic content) and antiradical capacity of the soluble extracts. Operating at 80 °C and 80 kHz, the models predicted a compromise optimum extraction conditions at ~35 min, solid liquid ratio of ~2 g/100 g, and ultrasound amplitude of ~79%. Under these conditions, 40.3% carrageenan yield was attained and this product presented 46% sulfate and good mechanical properties, a viscoelastic modulus of 741.4 Pa, with the lowest gelling temperatures of 39.4 °C. The carrageenans also exhibited promising antiproliferative properties on selected human cancer cellular lines, A-549, A-2780, HeLa 229, and HT-29 with EC50 under 51.9 µg/mL. The dried soluble extract contained 20.4 mg protein/g, 11.3 mg gallic acid eq/g, and the antiradical potency was equivalent to 59 mg Trolox/g.


Assuntos
Carragenina/isolamento & purificação , Carragenina/farmacologia , Proliferação de Células/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Rodófitas/química , Antioxidantes/química , Carragenina/análise , Carragenina/química , Linhagem Celular Tumoral , Géis , Humanos , Fenômenos Mecânicos , Fenóis/química , Extratos Vegetais/análise , Extratos Vegetais/química , Reologia , Sulfatos/análise , Temperatura , Ondas Ultrassônicas , Viscosidade , Água/química
8.
J Sci Food Agric ; 101(14): 5851-5860, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33788968

RESUMO

BACKGROUND: Basil seed gum (BSG) is a novel polysaccharide that has been found wide application in the food industry. It can be used in whipped cream due to its thickening and emulsifying properties. The effect of BSG and κ-carrageenan on the structure-rheology relationships of whipped cream was evaluated. RESULTS: The viscosity of cream containing BSG was higher than that of carrageenan. Basil seed gum resulted in a strong capacity to improve the viscosity of the cream. Rheological results showed the low-frequency dependence of the elastic modulus was improved by BSG, which had a strong effect on the rigidity of the emulsion. The fracture strain of the creams containing BSG or κ-carrageenan was between the normal cream and acidified caseinate stabilized emulsion foam. It was found that the protein segments of BSG could be adsorbed at the oil-water interface, resulting in the formation of a pseudo-gel network, which creates a stronger molecular protein network in the whipped cream. Microstructure study revealed that whipped cream containing κ-carrageenan exhibited some flocculation, which could be caused by non-adsorbed polysaccharides or proteins. In contrast, cream containing BSGshowed more voids, which have considerably decreased by fat content and enhance the foam structure. CONCLUSION: As a result, synergistic interactions between proteins and polysaccharides (BSG and κ-carrageenan) could promote the development of a cross-linked network. Indeed, due to its high levels of hydrophilicity, BSG absorbs water, acts as a thickening agent, and competes against caseinate at the interfaces and is incorporated into whipped cream to provide a more desirable physical structure for the product. © 2021 Society of Chemical Industry.


Assuntos
Carragenina/análise , Aditivos Alimentares/análise , Ocimum basilicum/química , Gomas Vegetais/análise , Emulsões/análise , Manipulação de Alimentos , Reologia , Sementes/química , Viscosidade
9.
J Sci Food Agric ; 101(4): 1389-1395, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32835415

RESUMO

BACKGROUND: Salted duck egg white (SDEW) is a major by-product during salted egg yolk manufacturing. Due to the high salt concentration, SDEW has not been efficiently utilized. Moreover, functional properties of SDEW are altered by salt during pickling. To improve the functional properties, the effect of κ-carrageenan (κ-CAR) addition on the protein structure and gel properties of SDEW was investigated in this study. RESULTS: The surface hydrophobicity and free sulfhydryl content of SDEW protein increased, while total sulfhydryl content decreased significantly with the addition of κ-CAR (0.02-0.10%). Fourier-transform infrared spectroscopy analysis revealed that the relative content of α-helix and ß-turn decreased, ß-sheet and random coil increased, indicating the variation tendency of protein structure from order to disorder. As κ-CAR addition increased, the texture profiles including hardness, gumminess, chewiness, springiness, cohesiveness and resilience of SDEW gel were all improved. Water holding capacity increased significantly by 32.33% in the presence of 0.10% κ-CAR addition. The scanning electron microscopy indicated that the microstructure of SDEW/κ-CAR mixed gel was more smooth and compact. CONCLUSION: The results suggested that adding κ-CAR can be an effective method to improve gel quality of SDEW. This study is expected to provide theoretical basis for modification of SDEW protein, as well as preparation of food ingredients with better gel properties from SDEW. © 2020 Society of Chemical Industry.


Assuntos
Carragenina/análise , Clara de Ovo/química , Animais , Patos , Gema de Ovo/química , Aditivos Alimentares/análise , Manipulação de Alimentos , Géis/química , Dureza , Interações Hidrofóbicas e Hidrofílicas , Cloreto de Sódio/análise , Espectroscopia de Infravermelho com Transformada de Fourier
10.
PLoS One ; 15(9): e0239097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925956

RESUMO

The eucheumatoids Kappaphycus and Eucheuma are cultivated in tropical or subtropical regions for the production of carrageenan, a hydrocolloid widely used in the food and cosmetic industries. Kappaphycus alvarezii is a highly valued economic crop in the Coral Triangle, with the Philippines, Indonesia and Malaysia ranked among the largest producers. In the absence of measures to mitigate climate change, extreme events including heatwaves, typhoons, severe El Niño and La Niña, are expected to increase in frequency and magnitude. This inadvertently brings adverse effects to the seaweed cultivation industry, especially in the tropics. Temperatures are rapidly reaching the upper limit of biologically tolerable levels and an increase in reports of ice-ice and pest outbreaks is attributable to these shifts of environmental parameters. Nevertheless, few reports on the response of eucheumatoids to a changing environment, in particular global warming, are available. Understanding the responses and possible mechanisms for acclimation to warming is crucial for a sustainable seaweed cultivation industry. Here, the physiological and biochemical responses of K. alvarezii to acute warming indicated that the strain used in the current study is unlikely to survive sudden increases in temperature above 36°C. As temperature increased, the growth rates, photosynthetic performance, phycocolloid quality (carrageenan yield, gel strength and gel viscosity) and pigment content (chlorophyll-a, carotenoid and phycobiliproteins) were reduced while the production of reactive oxygen species increased indicating the occurrence of stress in the seaweeds. This study provides a basis for future work on long term acclimation to elevated temperature and mesocosm-based multivariate studies to identify heat-tolerant strains for sustainable cultivation.


Assuntos
Aquecimento Global , Rodófitas/fisiologia , Aclimatação , Carragenina/análise , Carragenina/metabolismo , Mudança Climática , Fotossíntese , Pigmentos Biológicos/análise , Pigmentos Biológicos/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Rodófitas/química , Rodófitas/crescimento & desenvolvimento , Temperatura
11.
J Food Sci ; 85(1): 50-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31880331

RESUMO

The aim of this work was to study the influence of ι- and κ-carrageenan addition to strawberry sorbet prepared by various freezing methods (cryostat and conventional freezer) on freezing kinetics and ice crystals structure. Four variants of strawberry-based sorbet were prepared: with no additive, with 0.1% addition of ι- and κ-carrageenan, and 1:1 blend of both. Freezing curves and freezing time, as well as the size and morphology of ice crystals, were analyzed. The addition of carrageenan stabilizers resulted in freezing process elongation. Reference samples were characterized by different dynamics of the freezing process. The addition of carrageenan increased the final temperature of the samples, compared to the reference sample (even 2.6 °C of difference). Additives reduced ice crystals growth. The most efficient was mixture of both fractions of carrageenan--the samples in this variant frozen in conventional freezer were characterized by the smallest ice crystals diameter--average 5.44 µm, while for the reference sample it was 17.79 µm. PRACTICAL APPLICATION: This research can give a new path for the carrageenan's hydrolysates application--not only for dairy products. Iota carrageenan fraction was recommended for dairy products according to its water-holding capacity in the presence of calcium ions. This study showed that mix of ι- and κ-carrageenan could bring positive results to such product as sorbet without any milk proteins addition. This experiment data could also be helpful when optimizing frozen desserts production in small gastronomy--especially the temperature and time of freezing modifications.


Assuntos
Carragenina/análise , Aditivos Alimentares/análise , Fragaria/química , Frutas/química , Extratos Vegetais/química , Conservação de Alimentos/métodos , Congelamento , Gelo/análise , Temperatura , Água/química
12.
Sci Rep ; 9(1): 6379, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015498

RESUMO

A novel disposable electrochemical biosensor based on immobilized calf thymus double-stranded DNA (dsDNA) on the carbon-based screen-printed electrode (SPE) is developed for rapid biorecognition of carrageenan by using methylene blue (MB) redox indicator. The biosensor protocol for the detection of carrageenan is based on the concept of competitive binding of positively charged MB to the negatively charged dsDNA and carrageenan. The decrement in the MB cathodic peak current (ipc) signal as a result of the released MB from the immobilized dsDNA, and attracted to the carrageenan can be monitored via differential pulse voltammetry (DPV). The biosensor showed high sensitivity and selectivity to carrageenan at low concentration without interference from other polyanions such as alginate, gum arabic and starch. Calibration of the biosensor with carrageenan exhibited an excellent linear dependence from 1-10 mg L-1 (R2 = 0.98) with a detection limit of 0.08 mg L-1. The DNA-based carrageenan biosensor showed satisfactory reproducibility with 5.6-6.9% (n = 3) relative standard deviations (RSD), and possessing several advantages such as simplicity, fast and direct application to real sample analysis without any prior extensive sample treatments, particularly for seaweeds and food analyses.


Assuntos
Técnicas Biossensoriais , Carragenina/análise , DNA/análise , Carragenina/química , Técnicas Eletroquímicas , Alimentos , Concentração de Íons de Hidrogênio , Íons , Azul de Metileno/química , Concentração Osmolar , Polieletrólitos , Polímeros , Sódio/farmacologia , Eletricidade Estática
13.
PLoS One ; 14(4): e0214580, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30990847

RESUMO

A potentiometric whole cell biosensor based on immobilized marine bacterium, Pseudomonas carrageenovora producing κ-carrageenase and glycosulfatase enzymes for specific and direct determination of κ-carrageenan, is described. The bacterial cells were immobilized on the self-plasticized hydrogen ion (H+)-selective acrylic membrane electrode surface to form a catalytic layer. Hydrogen ionophore I was incorporated in the poly(n-butyl acrylate) [poly(nBA)] as a pH ionophore. Catalytic decomposition of κ-carrageenan by the bienzymatic cascade reaction produced neoagarobiose, an inorganic sulfate ion and a proton. The latter was detectable by H+ ion transducer for indirect potentiometric quantification of κ-carrageenan concentration. The use of a disposable screen-printed Ag/AgCl electrode (SPE) provided no cleaning requirement and enabled κ-carrageenan detection to be carried out conveniently without cross contamination in a complex food sample. The SPE-based microbial biosensor response was found to be reproducible with high reproducibility and relative standard deviation (RSD) at 2.6% (n = 3). The whole cell biosensor demonstrated a broad dynamic linear response range to κ-carrageenan from 0.2-100 ppm in 20 mM phosphate buffer saline (PBS) at pH 7.5 with a detection limit at 0.05 ppm and a Nernstian sensitivity of 58.78±0.87 mV/decade (R2 = 0.995). The biosensor showed excellent selectivity towards κ-carrageenan compared to other types of carrageenans tested e.g. ι-carrageenan and λ-carrageenan. No pretreatment to the food sample was necessary when the developed whole cell biosensor was employed for direct assay of κ-carrageenan in dairy product.


Assuntos
Técnicas Biossensoriais , Carragenina/análise , Potenciometria/métodos , Pseudomonas/metabolismo , Algoritmos , Proteínas de Bactérias/metabolismo , Células Imobilizadas/metabolismo , Meios de Cultura , Eletrodos , Hidrogênio , Íons , Cinética , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Fatores de Tempo
14.
Food Chem ; 242: 16-21, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037672

RESUMO

Method development for monitoring economically motivated food adulteration is pivotal for preventing health problems caused by illegal food additives. In this work, low-field nuclear magnetic resonance (LF-NMR) spectroscopy and magnetic resonance imaging (MRI) was applied for the detection and mapping of adulterated prawns injected with different hydrocolloids including gelatin, carrageenan, agar, amorophophallus konjac and xanthan gum. The characteristic T2 fitting curves were obtained which can be used to tell apart adulterated prawns from normal ones. Furthermore, the benefit from high quality LF-MRI images showed the major accumulation site of the hydrocolloids injected in prawn. The location of these injections was mainly confined to well resolved accumulation in brain region and three following subtle sites: back, tail and claws. Different hydrocolloids can be successfully distinguished in adulterated prawns with principal component analysis. Therefore, rapid, non-invasive and low-cost LF-NMR technique offers a powerful tool for the identification of hydrocolloids adulteration in real-time.


Assuntos
Coloides/análise , Aditivos Alimentares/análise , Contaminação de Alimentos/análise , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Alimentos Marinhos/análise , Ágar/administração & dosagem , Ágar/análise , Amorphophallus/química , Carragenina/administração & dosagem , Carragenina/análise , Coloides/administração & dosagem , Aditivos Alimentares/administração & dosagem , Contaminação de Alimentos/prevenção & controle , Gelatina/administração & dosagem , Gelatina/análise , Polissacarídeos Bacterianos/administração & dosagem , Polissacarídeos Bacterianos/análise
15.
J Food Sci ; 82(10): 2313-2320, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28892153

RESUMO

This study investigated the efficacy of ultra-high pressure homogenization (UHPH) in the presence or absence of added hydrocolloids for enhancing a range of physic-chemical properties of soymilk-which are important for extending shelf-life. Soymilk preparations containing different concentrations (0.01%, 0.02%, and 0.05%, w/v) of 2 different hydrocolloids (κ-carrageenan, κ-C, and gum Arabic, GA) were subjected to 3 different levels of UHPH (70, 140, and 210 MPa) and stored in sterilized containers at 4 °C. Emulsion properties of the soymilk preparations were analyzed over a period of 5 weeks. The results showed that soymilk with 0.05% κ-C had markedly improved storage properties, evident by significantly (P < 0.05) enhanced surface energy and absolute ζ potential values compared to the unhomogenized soymilk with no hydrocolloid (16% and 39% augmentations, respectively) at the 1st week of storage. This trend continued throughout the entire period of study. The soymilk containing 0.05% κ-C also exhibited significantly (P < 0.05) lower (60%) mean globular particle size at the initial week compared to the latter ones and maintained the trend throughout the 3rd week of storage. The study can potentially lead to a considerable economic benefit to the soymilk industry by providing valuable information to extend shelf-life of soymilk. PRACTICAL APPLICATION: Soymilk is one of the most important soy products, and as a beverage, it is rapidly gaining popularity in the Western markets. However, it tends to form precipitates during storage to affect quality of the product. This study used a 2-prong approach of ultra-high pressure homogenization and addition of hydrocolloids to prevent aggregation of soymilk particles and the retention of antioxidant capacity. The results showed enhancement of the quality of soymilk during storage. The techniques developed can be adopted by the food industry.


Assuntos
Coloides/química , Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Leite de Soja/química , Carragenina/análise , Emulsões/análise , Manipulação de Alimentos/instrumentação , Armazenamento de Alimentos , Goma Arábica/análise , Tamanho da Partícula , Pressão
16.
Food Chem Toxicol ; 107(Pt A): 208-214, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28651808

RESUMO

This paper is an addendum to a 2016 paper outlining pitfalls and parameters to consider in the conduct of food additive research with carrageenan (Fd. Chem. Tox. 87, 31-44 (2016)). The literature on the food additive, "carrageenan," contains many publications which either erroneously misuse the name, carrageenan, for a sample which is not carrageenan, but "degraded carrageenan" or "poligeenan" and also conduct studies without understanding the physical/chemical properties of carrageenan. Degraded carrageenan and poligeenan are not food additives and have a completely different physical/chemical and toxicological properties from carrageenan. Two recent publication examples, one in vivo and one in vitro, demonstrate the serious misunderstanding promulgated by incorrect sample identity/purity and poor study conduct. These new publication examples reiterate the problems in the literature summarized by the Weiner (2016). It is important to have thorough, rigorous peer review of all studies using carrageenan in vivo or in vitro.


Assuntos
Carragenina/análise , Aditivos Alimentares/química , Extratos Vegetais/química , Carragenina/metabolismo , Aditivos Alimentares/isolamento & purificação , Aditivos Alimentares/metabolismo , Humanos , Peso Molecular , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Ligação Proteica , Proteínas/química , Proteínas/metabolismo
17.
Food Sci Technol Int ; 22(7): 609-620, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26924843

RESUMO

People suffering from lactose intolerance cannot digest milk or lactose-containing foods. Lactose-free diet is essential for them since they do not have the ability to produce lactase to breakdown milk sugar. Physical properties of lactose-free dairy desserts will most probably be different than that of lactose containing ones because of lactose hydrolysis. In this study, it was aimed to analyze the rheological and textural behaviors of different lactose-free dessert formulations containing different gum types and different waxy maize starch and sucrose concentrations. Waxy maize starch was used at concentrations of 0.032 g·mL-1, 0.040 g·mL-1, and 0.048 g·mL-1 In addition to waxy maize starch, guar gum, gum arabic, or κ-carrageenan at two different concentrations (1.0% w/w and 0.5% w/w) was added. Sucrose was added at concentrations of 0.14 g·mL-1 and 0.10 g·mL-1 in lactose-free desserts. Power law model was found to be suitable to explain the flow behavior of desserts. The storage and loss modulus of lactose-free desserts were higher than that of lactose-containing desserts. The κ-Carrageenan was found to be the most effective gum for structure build-up.


Assuntos
Laticínios/análise , Lactose/análise , Reologia , Carragenina/análise , Fenômenos Químicos , Aditivos Alimentares/análise , Análise de Alimentos , Manipulação de Alimentos , Galactanos/análise , Goma Arábica/análise , Mananas/análise , Gomas Vegetais/análise , Amido/química , Sacarose/análise , Zea mays/química
18.
Food Chem ; 205: 14-22, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27006208

RESUMO

Concerns about meat authenticity are increasing recently, due to great fraud scandals. This paper analysed real samples (43 adulterated and 12 controls) originated from criminal networks dismantled by the Brazilian Police. This fraud consisted of injecting solutions of non-meat ingredients (NaCl, phosphates, carrageenan, maltodextrin) in bovine meat, aiming to increase its water holding capacity. Five physico-chemical variables were determined, protein, ash, chloride, sodium, phosphate. Additionally, infrared spectra were recorded. Supervised classification PLS-DA models were built with each data set individually, but the best model was obtained with data fusion, correctly detecting 91% of the adulterated samples. From this model, a variable selection based on the highest VIPscores was performed and a new data fusion model was built with only one chemical variable, providing slightly lower predictions, but a good cost/performance ratio. Finally, some of the selected infrared bands were specifically associated to the presence of adulterants NaCl, tripolyphosphate and carrageenan.


Assuntos
Contaminação de Alimentos/análise , Carne/análise , Carne/classificação , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Brasil , Carragenina/análise , Bovinos , Modelos Teóricos , Polifosfatos/análise , Cloreto de Sódio/análise , Água/análise
19.
Meat Sci ; 98(4): 615-21, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25089785

RESUMO

The optimization of a gelled oil-in-water emulsion was performed for use as fat replacer in the formulation of ω-3 PUFA-enriched cooked meat products. The linseed oil content, carrageenan concentration and surfactant-oil ratio were properly combined in a surface response design for maximizing the hardness and minimizing the syneresis of the PUFA delivery system. The optimal formulation resulted in a gelled emulsion containing 40% of oil and 1.5% of carrageenan, keeping a surfactant-oil ratio of 0.003. The gel was applied as a partial fat replacer in a Bologna-type sausage and compared to the use of an O/W emulsion also enriched in ω-3. Both experimental sausages contributed with higher ω-3 PUFA content than the control. No sensory differences were found among formulations. The selected optimized gelled oil-in-water emulsion was demonstrated to be a suitable lipophilic delivery system for ω-3 PUFA compounds and applicable in food formulations as fat replacer.


Assuntos
Emulsões/análise , Ácidos Graxos Ômega-3/análise , Manipulação de Alimentos/métodos , Géis/análise , Produtos da Carne/análise , Animais , Carragenina/análise , Óleo de Semente do Linho/análise , Suínos
20.
Artigo em Inglês | MEDLINE | ID: mdl-25167218

RESUMO

A method was developed and validated in support of a 28-day feeding study of swine-adapted infant formula stabilised with carrageenan administered to neonatal piglets. Carrageenan concentrations in the test formulations were 0, 300, 1000 and 2250 mg kg(-1) formula. Extraction of carrageenan from swine-adapted infant formula was achieved by breaking carrageenan-protein cross-linkages using saturated sodium chloride, followed by separation of the non-gelling carrageenan fraction via centrifugation. The extraction of carrageenan from formula was successful with respect to consistent recovery of the non-gelling carrageenan fraction from both test and control formula samples. Molecular weight analysis (Mw) of the recovered carrageenan fractions from the test and control formula samples confirmed that the carrageenan used to manufacture the formula was not degraded during the infant formula production process and subsequent storage for 4 months covering the 28-day piglet dietary feeding study. Carrageenan has excellent stability in infant formulations.


Assuntos
Ração Animal/análise , Carragenina/análise , Análise de Alimentos/métodos , Conservantes de Alimentos/análise , Animais , Animais Recém-Nascidos , Carragenina/química , Carragenina/isolamento & purificação , Cromatografia em Gel , Conservantes de Alimentos/química , Conservantes de Alimentos/isolamento & purificação , Armazenamento de Alimentos , Alimentos em Conserva/análise , Humanos , Hidrólise , Fórmulas Infantis/química , Recém-Nascido , Peso Molecular , Nefelometria e Turbidimetria , Concentração Osmolar , Refratometria , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Sus scrofa
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