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1.
Food Res Int ; 173(Pt 1): 113245, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803558

RESUMO

The lipid-lowering effect of dry beans and their impact on lipid and cholesterol metabolism have been established. This study investigates the underlying mechanisms of this effect and explore how the structural integrity of processed beans influences their ability to modulate lipolysis using the INFOGEST static in vitro digestion model. Dietary fiber (DF) fractions were found to decrease lipolysis by increasing the digesta viscosity, leading to depletion-flocculation and/or coalescence of lipid droplets. Bean flours exhibited a more pronounced reduction in lipolysis compared to DF. Furthermore, different levels of bean structural integrity showed varying effects on modulating lipolysis, with medium-sized bean particles demonstrating a stronger reduction. Hydrothermal treatment compromised the ability of beans to modulate lipid digestion, while hydrostatic-pressure treatment (600 MPa/5min) enhanced the effect. These findings highlight that the lipid-lowering effect of beans is not solely attributed to DF but also to the overall bean matrix, which can be manipulated through processing techniques.


Assuntos
Phaseolus , Phaseolus/química , Fibras na Dieta/metabolismo , Lipólise , Lipídeos , Digestão
2.
Lett Appl Microbiol ; 76(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37019823

RESUMO

Delmopinol hydrochloride (delmopinol) is a cationic surfactant that is effective for treating and preventing gingivitis and periodontitis. This study evaluated the effectiveness of delmopinol for reducing attachment of Campylobacter jejuni to chicken meat, stainless steel, and high-density polyethylene (HDPE). These test materials were spot-inoculated with a C. jejuni culture. After 10 min, samples were sprayed with 0.5% or 1.0% delmopinol, 0.01% sodium hypochlorite, or distilled water. After a 1, 10, or 20 min contact time, samples were rinsed, which were serially diluted onto Campy-Cefex Agar. For additional samples, solutions were applied before inoculation with C. jejuni. Cultures remained undisturbed for 1, 10, or 20 min. Samples were then rinsed and plated as above. When C. jejuni was inoculated before treatments, 1% delmopinol application led to mean log reductions of 1.26, 3.70, and 3.72 log cfu ml-1, greater than distilled water alone, for chicken, steel and HDPE, respectively. When C. jejuni was inoculated after spray treatments, 1% delmopinol reduced C. jejuni by 2.72, 3.20, and 3.99 mean log cfu ml-1 more than distilled water for chicken, steel and HDPE, respectively. Application of 1% delmopinol, resulted in a significantly (P < .05) greater log reduction than a 0.01% sodium hypochlorite or distilled water application.


Assuntos
Campylobacter jejuni , Animais , Polietileno , Aço Inoxidável , Aves Domésticas , Hipoclorito de Sódio/farmacologia , Carne , Microbiologia de Alimentos , Galinhas , Água , Contagem de Colônia Microbiana
3.
Wounds ; 35(1): E17-E21, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36749993

RESUMO

INTRODUCTION: NPWT is a surgical dressing that combines polyurethane foam with the subsequent application of continuous or intermittent negative pressure. NPWT facilitates granulation tissue production by macrostrain, microstrain and, if desired, fluid instillation. Sealing the polyurethane foam over the wound bed is achieved using acrylic drapes; however, this can be difficult to use in some anatomic sites. Failure to achieve an effective seal can necessitate additional supplies, which has led to increased innovation in developing a more effective NPWT seal over the target wound bed. Obtaining an effective pressure seal on the feet or hands can be difficult because these anatomic sites have distinct curvature for each digit, with multiple interdigital web spaces and independent mobility. In this case report, the authors propose a technique to apply either an acrylic drape or combination acrylic and soft silicone drape utilizing the "sandwich technique" to seal NPWT foam quickly and efficiently to the feet or hands.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Humanos , Tratamento de Ferimentos com Pressão Negativa/métodos , Cicatrização , Tecido de Granulação , Extremidade Superior
4.
Br J Neurosurg ; : 1-7, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35445637

RESUMO

BACKGROUND: Craniofacial fibrous dysplasia (CFD) typically occurs in the facial bones and anterior cranial vault and can produce both disfigurement and functional limitations for patients disfigurement. Treatment consists of reducing the abnormal bone. Bone contouring can become challenging when the exposure does not extend to the corresponding normal contralateral structures for comparison or when normal landmarks are not available, which may compromise the overall aesthetic outcome. We describe a technique using dynamic mirroring to accurately contour the involved part of the cranium in a case of giant CFD. OBSERVATIONS: A 49-year-old male presented with a giant deforming fibrous dysplasia of the right mastoid and parieto-temporo-occiput that was causing functional limitations due to the size of the bony mass. This was managed with multidisciplinary bony reduction. Several neurovascular structures were in proximity to the areas of planned drilling of the expansile lesion, and dynamic mirroring of the uninvolved left skull was utilized to maximize safety and symmetry of reduction. High-speed drilling of the right occipital bone was performed until the navigation system alerted the surgeon that symmetric depth had been achieved. There were no complications from the procedure and this technique maximized the limits of symmetric reduction without significantly increasing surgical complexity or duration. LESSONS: Dynamic mirroring of bony structures in the posterior cranium is not commonly employed in neurosurgical practice. This technique may help improve the aesthetic outcomes of bony reduction in craniofacial dysplasia and a variety of similarly managed bony lesions, contour cranioplasties, and in unilateral craniosynostosis surgery.

5.
Food Chem ; 381: 132289, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35123222

RESUMO

Economically feasible and effective hop drying strategies are urgently needed to respond to the increasing number of microbrewers in US. In this study, hops were dried by dehydrator-drying (52 °C), oven-drying (52 °C) and freeze-drying (25 °C) until the final moisture content reached 8-10%. Headspace solid-phase microextraction-gas chromatography-mass spectrometry-olfactometry (HS-SPME-GC-MS-O) was employed to analyze the aroma profiles in all dried hops. Methyl octanoate, ß-myrcene, trans-α-bergamotene, linalool and geraniol were perceived as high-intensity aromas in all samples. Generally, dehydrator-dried hops contained the highest contents of aroma compounds among all groups, showing an increase of 5-23% and 6-37% when compared to freeze- and oven-dried hops, respectively. Principal component and hierarchical cluster analyses also revealed aroma content differences from three drying methods. Dehydrator drying at 52 °C was therefore considered as an alternative and promising drying approach for smaller-scale hop processing, which can largely benefit regional producers and local craft breweries.


Assuntos
Humulus , Compostos Orgânicos Voláteis , Quimiometria , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
6.
MethodsX ; 8: 101389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430285

RESUMO

Bile salts (BS) play a key role in cholesterol and lipid metabolism as well as in many other key metabolic pathways. High performance liquid chromatography (HPLC) is the most common technique used to analyze BS in diverse type of samples. However, current HPLC analysis methods used to analyze and quantify single BS in in vitro digested samples showed poor separation of a complex mixture of BS. In this article, we improved a standard method originally used for quantifying individual BS in food samples subjected to in vitro digestion. We also adapted a method previously developed for BS examination in human blood samples to the analysis of these molecules in chyme samples obtained during simulated gastrointestinal digestion. Our method was simple and achieved a fast and successful separation and quantification of four primary BS (sodium salts of taurocholic, glycocholic, taurochenodeoxycholic and glycochenodeoxycholic acids).•A method used to analyze bile salts in human blood samples has been adapted to separate and quantify four primary bile salts in in vitro digested bean samples.•Addition of an ion-pair reagent led to complete separation of glycine and taurine conjugates of chenodeoxycholic and cholic acids within 10 min, and achieved good peak symmetry.•The minimum BS concentration that could be measured was as low as 0.03125mM.

7.
Foods ; 10(4)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805540

RESUMO

The light-protective effectiveness of titanium dioxide polylactic acid (TiO2 PLA) nanocomposite films (T-PLA) and oleic-acid-modified (OA_TiO2PLA) nanocomposite films was investigated in ready-to-drink (RTD) green tea infusions in oxygen-impermeable glass packaging. The stability of (-)-epigallocatechin gallate (EGCG) was evaluated in RTD green tea infusions in glass packaging covered with PLA (polylactic acid), T-PLA and OT-PLA under fluorescent light during 20 days of storage at 4 °C. Levels of EGCG and color change of RTD green tea infusions were determined. In addition, sensory tests for difference were conducted on green tea infusions in glass packaging without and with complete light protection during 10 days of storage at 4 °C. Of the panelists, 60% noticed sensory differences in the RTD green tea infusion in two different packaging conditions during 10 days of storage under fluorescent light by a triangle test (p < 0.05). During 20 days of storage, levels of EGCG with complete light protection decreased by 10.8% (0.73 mg/mL), and there was a 42.2% loss of EGCG (0.48 mg/mL) in RTD green tea infusions in the glass packaging covered by PLA film. Finally, 3% T-PLA preserved higher levels of EGCG in RTD green tea infusions compared to 1% T-PLA and OT-PLA.

8.
Sci Total Environ ; 753: 141776, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32911162

RESUMO

Globally, consumers judge their drinking water through its aesthetic qualities because tastes, odors, and appearances are readily detectable by untrained consumers. Consumer feedback is critical to the water industry for efficient resolution of aesthetic water quality issues, although consumer descriptions of taste and odor issues can sometimes be unfocused or confusing. A user-friendly approach can facilitate consumer communications to utilities in the challenging task of describing drinking water taste and odor issues. The purpose of this study was to develop a list of taste and odor descriptors and test a novel "check-if-apply" approach to describe drinking water quality. The final list contained 28 individual and/or groups of descriptors. 75 participants tested water samples impacted by various tastants or odorants: duplicate samples of chloraminated tap water, tap water with heptanal, tap water with 2-methylisoborneol (MIB), tap water with NaCl, bottled water, and bottled water with CuSO4. Participants used a 9-point hedonic scale (1 = 'dislike extremely'; 9 = 'like extremely') to rate overall liking of each sample, and they used the check-if-apply list to describe the taste or odor. Participants also answered a brief questionnaire and used a 5-point scale (1 = 'very difficult'; 5 = 'very easy') to evaluate their experience using the check-if-apply list. Significant differences were observed in acceptability and sensory profile of samples (p-value <0.05). Tap water with MIB had the lowest acceptability mean score (3.43 ± 1.74), while flavorless bottled water had the highest acceptability mean score (6.23 ± 1.47). 'Salty', 'metallic', 'chemical' and 'musty/earthy' were the dominant descriptors for NaCl, CuSO4, heptanal, and MIB, respectively. Most participants (81%) found the check-if-apply list as 'somewhat easy' to 'very easy' to use (mean = 3.44 ± 1.07) and suggested it as a user-friendly lexicon for consumers and utilities to communicate about water quality.


Assuntos
Água Potável , Água Potável/análise , Estética , Humanos , Odorantes/análise , Paladar , Qualidade da Água
9.
Food Res Int ; 137: 109337, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233047

RESUMO

The positive effect of common beans on reducing blood cholesterol levels has been linked to their ability to sequester bile salts (BS) and prevent their recycling. We have examined the preferences of major bean components (soluble/insoluble fiber, starch and proteins) to retain BS, and the role played by the bean matrix. Additionally, the kinetics of BS-release were evaluated in bean flours generated by a combination of hydrothermal or high-hydrostatic pressure (HHP), and mechanical treatments. An in vitro digestion model combined with dialysis was used to evaluate separately the retention of primary individual BS. Soluble fiber retained a significant proportion of BS mainly due to an increased digesta viscosity; however, the protein fraction exhibited the greatest BS retention without affecting viscosity. The thermal properties of proteins and starch were more significantly affected in presence of tauro-chenodeoxycholate, which correlated to the affinity of both fractions to retain more hydrophobic BS during digestion. Glyco-chenodeoxycholate and tauro-cholate were the most and least effectively retained BS by bean flours, respectively. Neither of the processing treatments had an impact on the binding preferences of bean flours to the primary BS; however, the largest BS retention was caused by HHP at 600 MPa. Bean materials preferentially delayed the release of chenodeoxycholate BS, which is probably related to BS micelle formation. These findings demonstrate that a combination of viscosity, molecular and compositional factors is triggering the BS-retention capacity of beans, and indicate the importance of evaluating contribution of individual bean components and as whole system.


Assuntos
Phaseolus , Ácidos e Sais Biliares , Digestão , Manipulação de Alimentos , Diálise Renal
10.
Polymers (Basel) ; 12(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142774

RESUMO

Fibers produced by electrospinning from biocompatible, biodegradable and naturally occurring polymers have potential advantages in drug delivery and biomedical applications because of their unique functionalities. Here, electrospun submicron fibers were produced from mixtures containing an exopolysaccharide (pullulan) and a small molecule with hosting abilities, hydroxypropyl-ß-cyclodextrin (HP-ß-CD), thus serving as multi-functional blend. The procedure used water as sole solvent and excluded synthetic polymers. Rheological characterization was performed to evaluate the impact of HP-ß-CD on pullulan entanglement concentration (CE); the relationship with electrospinnability and fiber morphology was investigated. Neat pullulan solutions required three times CE (~20% w/v pullulan) for effective electrospinning and formation of bead-free nanofibers. HP-ß-CD (30% w/v) facilitated electrospinning, leading to the production of continuous, beadless fibers (average diameters: 853-1019 nm) at lower polymer concentrations than those required in neat pullulan systems, without significantly shifting the polymer CE. Rheological, Differential Scanning Calorimetry (DSC) and Dynamic Light Scattering (DLS) measurements suggested that electrospinnability improvement was due to HP-ß-CD assisting in pullulan entanglement, probably acting as a crosslinker. Yet, the type of association was not clearly identified. This study shows that blending pullulan with HP-ß-CD offers a platform to exploit the inherent properties and advantages of both components in encapsulation applications.

11.
PLoS Pathog ; 16(10): e1008868, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33048992

RESUMO

While antiretroviral therapy (ART) has effectively revolutionized HIV care, the virus is never fully eliminated. Instead, immune dysfunction, driven by persistent non-specific immune activation, ensues and progressively leads to premature immunologic aging. Current biomarkers monitoring immunologic changes encompass generic inflammatory biomarkers, that may also change with other infections or disease states, precluding the antigen-specific monitoring of HIV-infection associated changes in disease. Given our growing appreciation of the significant changes in qualitative and quantitative properties of disease-specific antibodies in HIV infection, we used a systems approach to explore humoral profiles associated with HIV control. We found that HIV-specific antibody profiles diverge by spontaneous control of HIV, treatment status, viral load and reservoir size. Specifically, HIV-specific antibody profiles representative of changes in viral load were largely quantitative, reflected by differential HIV-specific antibody levels and Fc-receptor binding. Conversely, HIV-specific antibody features that tracked with reservoir size exhibited a combination of quantitative and qualitative changes marked by more distinct subclass selection profiles and unique HIV-specific Fc-glycans. Our analyses suggest that HIV-specific antibody Fc-profiles provide antigen-specific resolution on both cell free and cell-associated viral loads, pointing to potentially novel biomarkers to monitor reservoir activity.


Assuntos
Biomarcadores/sangue , Anticorpos Anti-HIV/sangue , Infecções por HIV/sangue , HIV-1/imunologia , Carga Viral/imunologia , Latência Viral/imunologia , Replicação Viral , Antirretrovirais/uso terapêutico , Anticorpos Anti-HIV/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/efeitos dos fármacos , Humanos , Carga Viral/efeitos dos fármacos , Latência Viral/efeitos dos fármacos
12.
Food Sci Nutr ; 8(8): 4505-4511, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32884730

RESUMO

Vine tea (Ampelopsis grossedentata) is a tea traditionally used in Chinese herbal medicine that is rich in the natural antioxidant dihydromyricetin (ampelopsin). In addition to its multiple health benefits, vine tea extracts and dihydromyricetin have been suggested as potential natural antioxidants for food applications, such as soybean oil and meat products. However, there is still little information available on vine tea chemistry, and in particular the volatile profile and sensory characteristics, which can affect product acceptability and restrict its use as a natural antioxidant. The objective of this exploratory study was to identify potential volatile components present in vine tea in order to support further research and applications in the food industry. Vine tea infusions brewed from commercial samples were characterized by acidic pH values and a dark, reddish-yellow color. Twenty-one volatile compounds were identified as potential flavor components of vine tea, including aldehydes and ketones. Further studies are suggested to quantify the volatile compounds and understand their importance to vine tea's aroma profile. Sensory studies are also suggested to access consumer's acceptability of vine tea and products containing vine tea as an ingredient.

13.
Front Psychol ; 11: 920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32528361

RESUMO

To characterize human emotions, researchers have increasingly utilized Automatic Facial Expression Analysis (AFEA), which automates the Facial Action Coding System (FACS) and translates the facial muscular positioning into the basic universal emotions. There is broad interest in the application of FACS for assessing consumer expressions as an indication of emotions to consumer product-stimuli. However, the translation of FACS to characterization of emotions is elusive in the literature. The aim of this systematic review is to give an overview of how FACS has been used to investigate human emotional behavior to consumer product-based stimuli. The search was limited to studies published in English after 1978, conducted on humans, using FACS or its action units to investigate affect, where emotional response is elicited by consumer product-based stimuli evoking at least one of the five senses. The search resulted in an initial total of 1,935 records, of which 55 studies were extracted and categorized based on the outcomes of interest including (i) method of FACS implementation; (ii) purpose of study; (iii) consumer product-based stimuli used; and (iv) measures of affect validation. Most studies implemented FACS manually (73%) to develop products and/or software (20%) and used consumer product-based stimuli that had known and/or defined capacity to evoke a particular affective response, such as films and/or movie clips (20%); minimal attention was paid to consumer products with low levels of emotional competence or with unknown affective impact. The vast majority of studies (53%) did not validate FACS-determined affect and, of the validation measures that were used, most tended to be discontinuous in nature and only captured affect as it holistically related to an experience. This review illuminated some inconsistencies in how FACS is carried out as well as how emotional response is inferred from facial muscle activation. This may prompt researchers to consider measuring the total consumer experience by employing a variety of methodologies in addition to FACS and its emotion-based interpretation guide. Such strategies may better conceptualize consumers' experience with products of low, unknown, and/or undefined capacity to evoke an affective response such as product prototypes, line extensions, etc.

14.
Food Chem ; 323: 126699, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32315945

RESUMO

Effect of varied LED color temperatures on photo-oxidation in 2% fat milk and protection efficiency of packaging with and without light-protective additives (LPA) under different color temperatures was firstly evaluated. Riboflavin (Rb) is one of the critical photo-sensitizers in 2% milk when exposed to LED light. Higher color temperature with higher relative intensity of Rb absorbance region resulted in lower Rb and vitamin A retention, lower dissolved oxygen content, and higher TBARS value in milk packaged with non-LPA packaging. Yellow pigmented packaging that completely blocked the Rb absorbance region of all three LED color temperatures successfully reduced the rate of degradation of milk nutrients and flavor. TiO2-added packaging partially block the destructive light wavelength; higher level of TiO2 provided a longer protection on milk freshness. Combination of appropriate LED color temperature and LPA-packaging provided a cost-effective solution for minimizing photo-oxidation in retail dairy case.

15.
Environ Res ; 186: 109442, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32302873

RESUMO

Grape pomace (GP) management has been a challenge worldwide. We have previously demonstrated a biorefinery process to recover oil and polyphenols, and produce biofuels from GP sequentially, although over 50% of GP solid waste remains post-processing. To approach zero solid waste during GP processing, herein a pyrolysis process was designed for converting GP and its secondary processing wastes to biochars, which were then evaluated for lead (Pb) adsorption from water. GP lignin pyrolyzed at 700 °C (GPL2700 biochar) with specific surface area of 485 m2/g showed the highest Pb adsorption capacity, and achieved 66.5% of Pb removal from an initially high concentration of 300 mg/L within 30 min. At low initial Pb concentrations (50-3000 µg/L), GPL2700 biochar could reduce Pb concentrations to 0.208-77.2 µg/L. In addition, experimental and modeling results revealed that both physisorption and chemisorption mechanisms were involved in the adsorption process of GPL2700 biochar.


Assuntos
Vitis , Água , Adsorção , Carvão Vegetal , Chumbo , Águas Residuárias
16.
Food Chem ; 310: 125699, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31810727

RESUMO

The capacity of high-fiber foods to sequester BS during digestion is considered a mechanism to lower serum-cholesterol. We investigated the effect of hydrothermal (HT) and high-hydrostatic-pressure (HHP) on the bile salt (BS)-binding ability of dry beans, and how this relates to changes in bean microstructure, fiber content (insoluble-IDF/soluble-SDF), and viscosity. HT and HHP-600 MPa led to significant IDF reduction, including resistant starch (RS), whereas 150-450 MPa significantly increased RS, without modifying IDF/SDF content. Microscopy analysis showed that heating disrupted the bean cell wall integrity, protein matrix and starch granules more severely than 600 MPa; however, tightly-packed complexes of globular starch granules-protein-cell wall fiber formed at HHP ≤ 450 MPa. While HT significantly reduced BS-binding efficiency despite no viscosity change, HHP-treatments maintained or enhanced BS-retention. 600 MPa-treatment induced the maximum BS-binding ability and viscosity. These results demonstrate that BS-binding by beans is not solely based on their fiber content or viscosity, but is influenced by additional microstructural factors.


Assuntos
Ácidos e Sais Biliares/metabolismo , Fibras na Dieta , Manipulação de Alimentos/métodos , Phaseolus/química , Phaseolus/ultraestrutura , Parede Celular/química , Parede Celular/ultraestrutura , Fibras na Dieta/análise , Pressão Hidrostática , Phaseolus/metabolismo , Proteínas de Vegetais Comestíveis/química , Solubilidade , Amido/química , Viscosidade
17.
Foods ; 8(12)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835812

RESUMO

To better evaluate potential uses for grape pomace (GP) waste, a comprehensive chemical composition analysis of GP in Virginia was conducted. Eight commercial white and red pomace samples (cv. Viognier, Vidal Blanc, Niagara, Petit Manseng, Petit Verdot, Merlot, Cabernet Franc, and Chambourcin) obtained from different wineries in Virginia, USA were used. For extractives, GPs contained 2.89%-4.66% titratable acids, 4.32%-6.60% ash, 4.62%-12.5% lipids with linoleic acid being the predominant (59.0%-70.9%) fatty acid, 10.4-64.8 g total phenolic content (gallic acid equivalents)/kg GP, 2.09-53.3 g glucose/kg GP, 3.79-52.9 g fructose/kg GP, and trace sucrose. As for non-extractives, GPs contained 25.2%-44.5% lignin, 8.04%-12.7% glucan, 4.42%-7.05% xylan, and trace amounts of galactan, arabinan, and mannan (less than 3% in total). Potential usages of these components were further examined to provide information on better valorization of GP. Considering the valuable extractives (e.g., polyphenols and oil) and non-extractives (e.g., lignin), designing a biorefinery process aiming at fully recover and/or utilize these components is of future significance.

18.
J Food Sci ; 84(8): 2147-2158, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313833

RESUMO

Multiple analytical methods are used for quantification of total polyphenols and total flavanols in fruit juices and beverages. Four methods were evaluated in this study: Folin-Ciocalteu (F-C), Lowenthal permanganate (L-P), 4-dimethylaminocinnamaldehyde (DMAC), and the bovine serum albumin (BSA) precipitation method. Method validation parameters, including working range, limit of detection, limit of quantitation, precision (repeatability), accuracy, and specificity, were assessed and compared. The F-C method was not specific to polyphenols, and the L-P method had the widest working range but lacked accuracy. The DMAC method was the most specific to flavanols, and the BSA method was not suitable for quantification of smaller flavanols, such as catechin and epicatechin. Quantitative performance was evaluated using commercial fruit juice samples (n = 14), apple juice samples of different cultivars (n = 22), and commercial ciders (n = 17). In general, the L-P titration method and DMAC method resulted in higher quantitative values than the F-C method and BSA precipitation method, respectively. However, ratios of results obtained by the L-P and F-C method ranged from 1 to 28, and ratios of results obtained by the DMAC and BSA precipitation method ranged from <1 to 280. This tremendous variation is likely due to variation in polyphenol composition and sample matrix. This information provides perspective for comparison of results obtained through these different methods, and a basis for choosing the most appropriate analytical method for quantification of polyphenols to address a specific research question when working with commercial fruit juice, apple juice from different apple cultivars, and commercial ciders. PRACTICAL APPLICATION: This study compared results obtained when four common polyphenol quantification methods were applied to a diverse selection of fruit juices and beverages with distinct polyphenol composition and sample matrix. The matrix and polyphenol composition of the samples significantly influenced the results. Our findings can help manufacturers of fruit-based products choose the most appropriate analytical method for polyphenol quantification as part of a quality assurance program or to convey information on dietary polyphenol content to consumers. An assessment of analytical method validation parameters is provided for each of the four methods, which will help users of these methods to understand their limitations.


Assuntos
Flavanonas/análise , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Polifenóis/análise , Frutas/química , Malus/química
19.
J Food Sci ; 84(6): 1420-1426, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31162865

RESUMO

Antioxidant activity of enzymatically modified soybean protein film with two different forms of added lignin (alkali lignin and lignosulfonate) was investigated using two stimulated food systems involving direct and indirect contact with soybean oil and fish fatty acid ethyl ester (FAEE). For the direct system, control and lignin-doped films were added to oil vials which were stored at dark under 40 °C whereas for indirect, films were used to cover oil-containing glass vials stored under standard commercial lighting conditions. Autoxidation of oil samples in the direct contact system was determined by peroxide value (PV), color, headspace oxygen, and volatile compounds, while for the indirect contact system photoxidation was determined by using PV and color. For the direct contact system with soybean oil, the PV was significantly lower during storage for both lignins used compared to the control (packaging system without lignin film). There was not a significant effect of lignin on the color of the oils (P > 0.05). Modified films tested in this study did not have a significant effect on headspace oxygen contents of oil samples; however, it resulted in reduced volatile compounds for both soybean oil and fish oil samples. Based on our observation, soybean protein films with lignin showed a greater impact on soybean oil than fish oil, possibly because of high initial oxidation levels in the fish oil. Enzymatic modified soy protein films with lignin are alternative active packaging materials for highly sensitive to oxidation by radical and UV light. PRACTICAL APPLICATION: Plastic packaging materials require the use of petroleum oil and are not biodegradable. Packaging materials made from renewable, biodegradable biopolymers are of great interest but often suffer from performance problems, such as weak mechanical properties compared to petroleum-based plastics. Applying modified biopolymeric film with lignin in the inner layer of food packaging system improved some aspects of their performance during storage, not only by preventing the migration of chemical compounds from the package to the food but also by radical scavenging activity and UV-blocking ability of the packaging system.


Assuntos
Antioxidantes , Biopolímeros/química , Óleos de Peixe , Embalagem de Alimentos/instrumentação , Lignina/química , Óleo de Soja , Animais , Ésteres , Embalagem de Alimentos/métodos , Oxirredução , Proteínas de Soja/química
20.
PLoS One ; 14(6): e0217043, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170189

RESUMO

This goal of this study was to highlight the importance of minerals in the diet of fish for meeting micronutrient requirements in the human diet. First arsenic, calcium, cadmium, copper, iron, molybdenum, magnesium, manganese, sodium, phosphorus, potassium, selenium, and zinc concentrations of twelve commercially available tilapia samples were measured. The nutritional value of fillets in regard to their mineral content were assessed to establish potential health benefits or risks for consumers. The health benefit value of selenium was also calculated. Positive health benefit values indicate that tilapia fillets in the United States marketplace of this study do not pose health risks associated with mercury exposures. Selenium was the trace mineral of interest. After the market study, a seven-week fish feeding trial was conducted to study the influence of organic versus inorganic dietary selenium on Nile tilapia (Oreochromis niloticus). Fish were fed two different diets enriched with the same concentration (0.01g kg-1) of selenium in form of inorganic (sodium selenite) or organic (seleno-L-methionine) selenium in triplicate groups. There were no significant differences between growth and biometrics of fish fed different diets (p>0.05). At the end of trial twelve fish from each treatment were collected. Fillets of fish fed organic selenium had selenium concentrations of 0.55 ± 0.01 µg g-1 which were significantly (p<0.05) higher than fish fed inorganic selenium at levels of 0.22 ± 0.008 µg g-1 or fish samples from the marketplace with a selenium level of 0.2 ± 0.03 µg g-1. Fish fed organic selenium also had significantly higher (p<0.05) plasma and kidney selenium in comparison to fish fed inorganic selenium. No significant differences (p>0.05) were observed in glutathione peroxidase activities in either the plasma or liver of Nile tilapia in the different treatment groups. This study shows that organic selenium is a better option for production of Nile tilapia fillets rich in selenium.


Assuntos
Suplementos Nutricionais/análise , Saúde , Selênio/análise , Tilápia , Animais , Dieta , Fígado/enzimologia , Peroxidase/sangue , Peroxidase/metabolismo , Inquéritos e Questionários , Tilápia/sangue , Tilápia/crescimento & desenvolvimento , Tilápia/metabolismo , Estados Unidos
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