Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 114
Filter
1.
Compr Rev Food Sci Food Saf ; 23(4): e13376, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38923698

ABSTRACT

Cold plasma treatment is an innovative technology in the food processing and preservation sectors. It is primarily employed to deactivate microorganisms and enzymes without heat and chemical additives; hence, it is often termed a "clean and green" technology. However, food quality and safety challenges may arise during cold plasma processing due to potential chemical interactions between the plasma reactive species and food components. This review aims to consolidate and discuss data on the impact of cold plasma on the chemical constituents and physical and functional properties of major food products, including dairy, meat, nuts, fruits, vegetables, and grains. We emphasize how cold plasma induces chemical modification of key food components, such as water, proteins, lipids, carbohydrates, vitamins, polyphenols, and volatile organic compounds. Additionally, we discuss changes in color, pH, and organoleptic properties induced by cold plasma treatment and their correlation with chemical modification. Current studies demonstrate that reactive oxygen and nitrogen species in cold plasma oxidize proteins, lipids, and bioactive compounds upon direct contact with the food matrix. Reductions in nutrients and bioactive compounds, including polyunsaturated fatty acids, sugars, polyphenols, and vitamins, have been observed in dairy products, vegetables, fruits, and beverages following cold plasma treatment. Furthermore, structural alterations and the generation of volatile and non-volatile oxidation products were observed, impacting the color, flavor, and texture of food products. However, the effects on dry foods, such as seeds and nuts, are comparatively less pronounced. Overall, this review highlights the drawbacks, challenges, and opportunities associated with cold plasma treatment in food processing.


Subject(s)
Food Handling , Plasma Gases , Plasma Gases/chemistry , Food Handling/methods , Fruit/chemistry , Vegetables/chemistry , Food Preservation/methods
2.
Environ Sci Technol ; 58(21): 9135-9146, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38754026

ABSTRACT

Reducing aviation emissions is important as they contribute to air pollution and climate change. Several alternative aviation fuels that may reduce life cycle emissions have been proposed. Comparative life cycle assessments (LCAs) of fuels are useful for inspecting individual fuels, but systemwide analysis remains difficult. Thus, systematic properties like fleet composition, performance, or emissions and changes to them under alternative fuels can only be partially addressed in LCAs. By integrating the geospatial fuel and emission model, AviTeam, with LCA, we can assess the mitigation potential of a fleetwide use of alternative aviation fuels on 210 000 shorter haul flights. In an optimistic case, liquid hydrogen (LH2) and power-to-liquid fuels, when produced with renewable electricity, may reduce emissions by about 950 GgCO2eq when assessed with the GWP100 metric and including non-CO2 impacts for all flights considered. Mitigation potentials range from 44% on shorter flights to 56% on longer flights. Alternative aviation fuels' mitigation potential is limited because of short-lived climate forcings and additional fuel demand to accommodate LH2 fuel. Our results highlight the importance of integrating system models into LCAs and are of value to researchers and decision-makers engaged in climate change mitigation in the aviation and transport sectors.


Subject(s)
Aviation , Vehicle Emissions , Models, Theoretical , Air Pollution , Climate Change , Air Pollutants/analysis
3.
Mol Nutr Food Res ; 68(6): e2300458, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38389157

ABSTRACT

SCOPE: Processing of whey protein concentrate (WPC) for infant formulas may induce protein modifications with severe consequences for preterm newborn development. The study investigates how conventional WPC and a gently processed skim milk-derived WPC (SPC) affect gut and immune development after birth. METHODS AND RESULTS: Newborn, preterm pigs used as a model of preterm infants were fed formula containing WPC, SPC, extra heat-treated SPC (HT-SPC), or stored HT-SPC (HTS-SPC) for 5 days. SPC contained no protein aggregates and more native lactoferrin, and despite higher Maillard reaction product (MRP) formation, the clinical response and most gut and immune parameters are similar to WPC pigs. SPC feeding negatively impacts intestinal MRP accumulation, mucosa, and bacterial diversity. In contrast, circulating T-cells are decreased and oxidative stress- and inflammation-related genes are upregulated in WPC pigs. Protein aggregation and MRP formation increase in HTS-SPC, leading to reduced antibacterial activity, lactase/maltase ratio, circulating neutrophils, and cytotoxic T-cells besides increased gut MRP accumulation and expression of TNFAIP3. CONCLUSION: The gently processed SPC has more native protein, but higher MRP levels than WPC, resulting in similar tolerability but subclinical adverse gut effects in preterm pigs. Additional heat treatment and storage further induce MRP formation, gut inflammation, and intestinal mucosal damage.


Subject(s)
Infant Formula , Milk , Humans , Infant, Newborn , Infant , Animals , Swine , Whey Proteins , Intestines/physiology , Infant, Premature , Inflammation
4.
Food Res Int ; 178: 113950, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38309910

ABSTRACT

Formation of Maillard reaction products (MRPs) is increasingly studied by the use of fluorescence spectroscopy, and most often, by measuring single excitation/emission pairs or use of unresolved spectra. However, due to the matrix complexity and potential co-formation of fluorescent oxidation products on tryptophan and tyrosine residues, this practice will often introduce errors in both identification and quantification. The present study investigates the combination of fluorescence excitation emission matrix (EEM) spectroscopy and parallel factor analysis (PARAFAC) to resolve the EEMs into its underlying fluorescent signals, allowing for better identification and quantification of MRPs. EEMs were recorded on a sample system of bovine serum albumin incubated at 40 °C for up to one week with either glucose, methylglyoxal or glyoxal added. Ten unique PARAFAC components were resolved, and assignment was attempted based on similarity with fluorescence of pure standards of MRPs and oxidation products and reported data from literature. Of the ten fluorescent PARAFAC components, tyrosine and buried and exposed tryptophan were resolved and identified, as well as the formation of specific MRPs (argpyrimidine and Nα-acetyl-Nδ-(5-methyl-4-imidazolon-2-yl)ornithine) and tryptophan oxidation products (kynurenine and dioxindolylalanine). The formation of the PARAFAC resolved protein modifications were qualitatively validated by liquid chromatography-mass spectrometry.


Subject(s)
Serum Albumin, Bovine , Tryptophan , Factor Analysis, Statistical , Glycation End Products, Advanced , Tyrosine
5.
Mol Nutr Food Res ; 67(24): e2300318, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37888862

ABSTRACT

SCOPE: Ready-to-feed liquid infant formulas (IFs) are increasingly being used for newborn preterm infants when human milk is unavailable. However, sterilization of liquid IFs by ultra-high temperature (UHT) introduces Maillard reaction products (MRPs) that may negatively affect systemic immune and kidney development. METHODS AND RESULTS: UHT-treated IF without and with prolonged storage (SUHT) are tested against pasteurized IF (PAST) in newborn preterm pigs as a model for preterm infants. After 5 days, blood leukocytes, markers of systemic immunity and inflammation, kidney structure and function are evaluated. No consistent differences between UHT and PAST pigs are observed. However, SUHT increases plasma TNFα and IL-6 and reduces neutrophils and in vitro response to LPS. In SUHT pigs, the immature kidneys show minor upregulation of gene expressions related to inflammation (RAGE, MPO, MMP9) and oxidative stress (CAT, GLO1), together with glomerular mesangial expansion and cell injury. The increased inflammatory status in SUHT pigs appears unrelated to systemic levels of MRPs. CONCLUSION: SUHT feeding may impair systemic immunity and affect kidney development in preterm newborns. The systemic effects may be induced by local gut inflammatory effects of MRPs. Optimal processing and length of storage are critical for UHT-treated liquid IFs for preterm infants.


Subject(s)
Infant Formula , Infant, Premature , Infant , Humans , Infant, Newborn , Animals , Swine , Animals, Newborn , Temperature , Inflammation , Kidney
6.
J Agric Food Chem ; 71(5): 2344-2355, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36715127

ABSTRACT

Caffeic acid (CA) and chlorogenic acid (CGA) are commonly found phenolic acids in plant-derived foods and beverages. Their corresponding adducts with cysteine (Cys) have been detected in coffee-containing beverages. However, despite the well-documented antioxidant and anti-inflammatory activity of CA and CGA, the immunomodulatory activities of the Cys adducts (CA-Cys and CGA-Cys) are unknown. The adducts were therefore synthesized, and their immunomodulatory effects were studied in lipopolysaccharide (LPS)-treated RAW 264.7 cells and compared to the activity of the parent phenolic acids. CA and CGA generally down-regulated the inflammatory responses. However, RNA-sequencing showed that the LPS-induced pathways related to Toll-like receptor signaling, chemokine signaling, and NOD-like receptor signaling, and JAK-STAT/MAPK signaling pathways were upregulated in adduct-treated cells relative to parent phenolic acids, while neurodegenerative disorder-related pathways and metabolic pathways were downregulated. Production of prostaglandin E2 (PGE2), interleukin-6, tumor necrosis factor-α (TNF-α), and reactive oxygen species (ROS) was all inhibited by CA and CGA (P < 0.05). PGE2 and TNF-α were further suppressed in adduct-stimulated cells (P < 0.05), but ROS production was increased. For example, TNF-α produced by 100 µM CGA-stimulated cells and 100 µM CGA-Cys adduct-stimulated cells were 4.46 ± 0.23 and 1.61 ± 0.18 ng/mL, respectively. Thus, the addition of the Cys moiety drastically alters the anti-inflammatory activity of phenolic compounds.


Subject(s)
NF-kappa B , Tumor Necrosis Factor-alpha , Tumor Necrosis Factor-alpha/metabolism , NF-kappa B/metabolism , Lipopolysaccharides/pharmacology , Amino Acids/metabolism , Reactive Oxygen Species/metabolism , Anti-Inflammatory Agents/pharmacology , Macrophages , Dinoprostone , Chlorogenic Acid/chemistry
7.
Food Res Int ; 163: 112187, 2023 01.
Article in English | MEDLINE | ID: mdl-36596128

ABSTRACT

Quinones are electrophilic compounds that can undergo Michael addition or Schiff base reaction with nucleophilic amines, but the effect of temperature has not been systematically studied. The aim of this study was to characterize how temperature affects the reaction mechanism and kinetics of 4-methylbenzoquinone (4MBQ) with lysine (Lys), Nα-acetyl Lys or Nε-acetyl Lys. The products were identified and characterized by LC-MS/MS, which revealed formation of Michael addition products, Schiff base, and a di-adduct in Lys and Nα-acetyl Lys-containing reaction mixtures. The product profiles were not affected by temperature in the range of 15-100 °C. NMR analysis proved that Michael addition of Nα-acetyl Lys occurred on the C5 position of 4MBQ. Rate constants for the reactions studied by stopped-flow UV-vis spectrophotometry under pseudo-first-order conditions where the amines were present in excess in the range 15 °C to 45 °C showed the α-amino groups of Lys are more reactive than the ε-groups. The kinetics results revealed that the temperature dependence of reaction rates followed the Arrhenius law, with activation energies in the order: Lys < Nε-acetyl Lys < Nα-acetyl Lys. Our results provide detailed knowledge about the temperature dependence of the reaction between Lys residues and quinones under conditions relevant for storage of foods.


Subject(s)
Lysine , Schiff Bases , Lysine/chemistry , Chromatography, Liquid , Temperature , Tandem Mass Spectrometry , Amines , Quinones
8.
Food Chem ; 403: 134406, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36191424

ABSTRACT

Protein-polyphenol interactions affect the structure, stability, and functional properties of proteins and polyphenols. Oxidized polyphenols (o-quinones) react rapidly with the sulfhydryl group of cysteine (Cys) residues, inducing covalent bonding between proteins and polyphenols. However, quantitative data on such reactions remain elusive, despite the importance of depicting the significance of such interactions on food structure and function. This work reports the synthesis, purification, and characterization of caffeic acid-cysteine (CA-Cys) and chlorogenic acid-cysteine (CGA-Cys) adducts and their stable isotope analogs, CA-[13C3,15N]Cys and CGA-[13C3,15N]Cys. A sensitive LC-MS/MS isotope dilution method was developed to simultaneously quantify these adducts in foods and beverages. Protein-bound CA-Cys and CGA-Cys were detected in the micro-molar range in milk samples with added CA and CGA, confirming covalent bonding between milk proteins and CA/CGA. These adducts were detected in commercial coffee-containing beverages but not in cocoa-containing drinks. Furthermore, the adducts were found to be partially stable during enzymatic protein hydrolysis.


Subject(s)
Chlorogenic Acid , Polyphenols , Polyphenols/chemistry , Chlorogenic Acid/metabolism , Cysteine/chemistry , Chromatography, Liquid , Tandem Mass Spectrometry , Beverages , Proteins
9.
Front Sociol ; 8: 1051189, 2023.
Article in English | MEDLINE | ID: mdl-38274842

ABSTRACT

Smoker stigma is a likely unintended consequence of tobacco polices aiming to denormalise smoking. Little is known about the dissemination of stigmatising attitudes toward smokers at the population level, including their associations with personal values. Applying a theoretical approach that conceptualises stigma as a cultural (moral and intersubjective) issue, we analyse the spread of perceived public stigma of smokers in Norway and factors predicting agreement with such a perception. Using merged data from the biennial national survey Norwegian Monitor 2011 and 2013 (N = 7,792), we tested whether the tendency to agree with a perceived public stigma of smokers differs by four indexes of value opposites ('puritanism/emancipation,' 'conformity/individuality,' 'tolerance/intolerance,' 'status/anti-status'), controlling for smoking status, SES, and demographics. Descriptive statistics and block-wise logistic regression models were applied. In the total sample, 59.1% agree with the statement that 'most people think less of a person who smokes.' Two of the four indexes of value opposites tested were associated with tendencies to agree with the perceived public stigma of smokers ('puritanism/emancipation' and 'status/anti-status'). Smokers with current plans to quit expressed the highest perceived public stigma, while ex-smokers expressed a higher perceived public stigma than never-smokers. Women, young people and respondents with high SES agree with a public stigma of smokers more than men, older people and respondents with low SES do. The perceived public stigma of smokers is high in Norway and varies to some extent with personal values, but also with socio-demographics and especially smoking status.

10.
Mol Nutr Food Res ; 66(20): e2200132, 2022 10.
Article in English | MEDLINE | ID: mdl-36052940

ABSTRACT

SCOPE: Ready-to-feed liquid infant formula is increasingly used for preterm infants when human milk is unavailable. These formulas are sterilized by ultra-high temperature treatment, but heating and storage may reduce bioactivity and increase formation of Maillard reaction products with potential negative consequences for immature newborns. METHODS AND RESULTS: Using preterm pigs as a model for sensitive newborn infants, the study tests the intestinal responses of feeding experimental liquid formula within 5 days. A pasteurized formula (PAST) with the same nutrient composition but less protein modifications serves as control to ultra-high temperature-treated formula without (UHT) and with prolonged storage (SUHT). Relative to PAST, UHT contains lower levels of lactoferrin and IgG. Additional storage (40 °C, 60 days, SUHT) reduces antimicrobial capacity and increases non-reducible protein aggregates and Maillard reaction products (up to 13-fold). Pigs fed SUHT have more diarrhea and show signs of intestinal inflammation (necrotizing enterocolitis) compared with pigs fed PAST and UHT. These clinical effects are accompanied by accumulation of Maillard reaction products, protein cross-links, and inflammatory responses in the gut. CONCLUSION: The results demonstrate that feeding UHT infant formulas, particularly after prolonged storage, adversely affects gut maturation and function in preterm pigs used as a model of preterm infants.


Subject(s)
Infant Formula , Intestines , Humans , Infant, Newborn , Infant , Swine , Animals , Animals, Newborn , Intestines/physiology , Glycation End Products, Advanced , Protein Aggregates , Lactoferrin , Temperature , Infant, Premature , Inflammation , Immunoglobulin G
11.
Food Chem ; 397: 133775, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-35917780

ABSTRACT

Protein-polyphenol adducts are formed upon covalent bonding between oxidized polyphenols and proteins. 4-Methylcatechol (4MC) is a polyphenol with origin in coffee and is oxidized to 4-methylbenzoquinone (4MBQ) under conditions used during food processing. The present study characterizes 4MBQ-induced covalent modifications on ß-lactoglobulin (ß-LG) from bovine milk, (henceforth ß-LQ) and the effect on protein digestibility. Significant thiol and amine loss was found in ß-LQ compared to ß-LG. Site-specific 4MBQ-induced modifications were identified on Cys, Lys, Arg, His and Trp in ß-LQ. No significant differences between ß-LG and ß-LQ on in vitro digestibility were observed by assessment with SDS-PAGE, degree of hydrolysis and LC-MS/MS unmodified peptide intensities. Cys-4MC adduct (1.7 ± 0.1 µmol/g) was released from ß-LQ after in vitro digestion. Thus, it is relevant to investigate how released Cys-4MC adducts are absorbed in vivo in future studies.


Subject(s)
Cysteine , Lactoglobulins , Catechols , Chromatography, Liquid , Cysteine/chemistry , Digestion , Lactoglobulins/chemistry , Polyphenols , Tandem Mass Spectrometry
12.
Food Chem ; 396: 133732, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35872499

ABSTRACT

Current analytical methods studying protein oxidation modifications require laborious sample preparation and chromatographic methods. Fluorescence spectroscopy is an alternative, as many protein oxidation products are fluorescent. However, the complexity of the signal causes misinterpretation and quantification errors if single emission spectra are used. Here, we analyzed the entire fluorescence excitation-emission matrix using the trilinear decomposition method parallel factor analysis (PARAFAC). Two sample sets were used: a calibration set based on known mixtures of tryptophan, tyrosine, and four oxidation products, and a second sample set of oxidized protein solutions containing UV-illuminated ß-lactoglobulin. The PARAFAC model succeeded in resolving the signals of the model systems into the pure fluorophore components and estimating their concentrations. The estimated concentrations for the illuminated ß-lactoglobulin samples were validated by liquid chromatography-mass spectrometry. Our approach is a promising tool for reliable identification and quantification of fluorescent protein oxidation products, even in a complex protein system.


Subject(s)
Fluorescent Dyes , Lactoglobulins , Calibration , Factor Analysis, Statistical , Spectrometry, Fluorescence/methods
14.
Food Chem (Oxf) ; 5: 100120, 2022 Dec 30.
Article in English | MEDLINE | ID: mdl-35865714

ABSTRACT

Odor-active volatile sulfur compounds are formed in heated food protein systems. In the present study, hydrogen sulfide (H2S) was found to be the most abundant sulfur volatile in whey protein solutions (whey protein isolate [WPI], a whey model system and single whey proteins) by gas chromatography-flame photometric detector (GC-FPD) analysis after heat treatments (60-90 °C for 10 min, 90 °C for 120 min and UHT-like treatment). H2S was detected in WPI after heating at 90 °C for 10 min, and was significantly increased at higher heat load (90 °C for 120 min and the UHT-like treatment). Site-specific LC-MS/MS-based proteomic analysis was conducted, monitoring desulfurization reactions in these protein systems to investigate the mechanism of H2S formation in heated WPI. Cysteine residues from beta-lactoglobulin were found to be responsible for the formation of H2S in heated WPI, presumably via beta-elimination.

15.
Food Chem ; 396: 133687, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35858513

ABSTRACT

The formation of Maillard reaction products, including Amadori compounds (determined as furosine), advanced glycation end products (AGEs), α-dicarbonyl and furfural compounds, as well as amino acid cross-links (lysinoalanine and lanthionine) was investigated in direct (DI) and indirect (IN) UHT-treated experimental liquid infant formula (IF) during storage at 40 °C. IN-IF had higher concentrations of all investigated compounds compared to DI-IF and low pasteurized IF. IN UHT treatment induced significantly higher concentrations of α-dicarbonyl compounds (glyoxal, methylglyoxal, 3-deoxyglucosone and 3-deoxygalactosone) compared to DI, which facilitated increased formation of AGEs (N-Ɛ-(carboxymethyl)lysine, methylglyoxal- and glyoxal-derived hydroimidazolones) in unstored IFs. During storage for 6 months, concentrations of furosine and AGEs increased while α-dicarbonyl compounds decreased. Principal component analysis indicated that differences between IN-IF and DI-IF disappeared after 2 months of storage. IN-IF had higher concentrations of lysinoalanine and lanthionine and lower concentrations of available lysine and arginine than DI-IF indicating higher loss of protein quality in IN-IF.


Subject(s)
Amino Acids , Maillard Reaction , Glycation End Products, Advanced/chemistry , Glyoxal/analysis , Humans , Infant Formula/analysis , Lysine/analysis , Lysinoalanine , Pyruvaldehyde/analysis
16.
J Sci Food Agric ; 102(14): 6293-6298, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35514139

ABSTRACT

BACKGROUND: Hempseed meal, a by-product of the hempseed oil processing stream, is a potential alternative source for food proteins. Efficient extraction of proteins from hempseed meal is challenging owing to differences in the structure and solubility of various protein fractions present in the seed. In the present study, protein was extracted from hempseed meal using four different solvents, including aqueous NaOH, KOH, NaHCO3 and NaCl, at four different concentrations with the aim of improving the recovery of protein fractions rich in essential amino acids. RESULTS: Extraction using alkaline solvents provided superior protein recovery (60-78%) compared with NaCl solution and control extractions (20-48% and 21%, respectively). The concentration of alkali or salt (0.25-1 mol L-1 ) had a minor but significant impact on the yield. Amino acid composition analysis revealed that hempseed meal contains 24% (54.5 ± 0.19 mg g-1 ) essential amino acids of total amino acids, and extraction with NaOH, KOH, NaHCO3 or NaCl did not improve the selective extraction of essential amino acids compared to control experiments. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis allowed the identification of edestin and albumin in the extracts obtained with NaHCO3 and NaCl solvents, with results further showing that the type of extraction solvent influences protein extraction selectivity. CONCLUSION: Although alkali solvents provide superior extraction yields, extraction with water resulted in extracts containing the highest proportion of proteins bearing essential amino acids. According to the results of SDS-PAGE, extraction using alkali solvents induced protein crosslinking. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Subject(s)
Seeds , Sodium Chloride , Albumins/chemistry , Amino Acids/analysis , Amino Acids, Essential/analysis , Cannabis , Plant Extracts , Seeds/chemistry , Sodium Chloride/analysis , Sodium Dodecyl Sulfate/analysis , Sodium Hydroxide , Solvents/chemistry , Water/analysis
17.
BMC Public Health ; 22(1): 631, 2022 03 31.
Article in English | MEDLINE | ID: mdl-35361172

ABSTRACT

BACKGROUND: In Norway, tobacco consumption is equally divided between combustible (cigarettes) and non-combustible (snus) tobacco. In the process of quitting, people who smoke can choose between several smoking cessation aids and strategies based on what is available on the market or what are recommended as cessation aids. A quit attempt may be planned or unplanned and consist of a gradual decline in consumption or an abrupt quitting. This study explores smoking cessation aids and strategies used at the latest quit attempt among people who have ever smoked. How prevalent is the use of various cessation aids and strategies, and do they correlate with each other? Are there any differences in successful quits depending on the use of a specific cessation aid or strategy? METHOD: We used repeated cross-sectional representative surveys in Norway for 2017, 2018, 2019 and 2020. The analytic sample consists of people aged 20 years or older who have ever smoked daily, more precisely current daily smokers with at least one quit attempt (n = 476), and former daily smokers who quit in 2012 or later (n = 397). Participants answered questions on cessation aids and strategies used at their last quit attempt. Logistic regression analysis was used to estimate the associations between cessation aids and strategies and sociodemographic and smoking-related variables and successful quit attempts. RESULTS: Fifty-six percent of people who ever smoked daily reported any use of cessation aids, and nicotine replacement therapy (NRT), snus and e-cigarettes were the most commonly used cessation aids. Snus and web/mobile use was associated with successful quits, while NRT was associated with unsuccessful quit attempts. When exclusive use was separated from the combined use of several aids, only snus was associated with successful quits. CONCLUSION: Snus use was found to be a "stand-alone" cessation aid, and only weakly associated with the use of other cessation aids. Further investigation of cessation aid preferences is needed, especially among smokers with little or no contact with health services and/or for whom traditional cessation aids have no appeal.


Subject(s)
Electronic Nicotine Delivery Systems , Smoking Cessation , Adult , Cross-Sectional Studies , Humans , Smokers , Tobacco Use Cessation Devices , Young Adult
18.
J Agric Food Chem ; 70(14): 4391-4406, 2022 Apr 13.
Article in English | MEDLINE | ID: mdl-35380828

ABSTRACT

Thermal treatment is often employed in food processing to tailor product properties by manipulating the ingredient functionality, but these elevated temperatures may accelerate oxidation and nutrient loss. Here, oxidation of different whey protein systems [α-lactalbumin (α-LA), ß-lactoglobulin (ß-LG), a mix of α-LA and ß-LG (whey model), and a commercial whey protein isolate (WPI)] was investigated during heat treatment at 60-90 °C and a UHT-like treatment by LC-MS-based proteomic analysis. The relative modification levels of each oxidation site were calculated and compared among different heat treatments and sample systems. Oxidation increased significantly in protein systems after heating at ≥90 °C but decreased in systems with higher complexity [pure protein (α-LA > ß-LG) > whey model > WPI]. In α-LA, Cys, Met, and Trp residues were found to be most prone to oxidation. In ß-LG-containing protein systems, Cys residues were suggested to scavenge most of the reactive oxidants and undergo an oxidation-mediated disulfide rearrangement. The rearranged disulfide bonds contributed to protein aggregation, which was suggested to provide physical protection against oxidation. Overall, limited loss of amino acid residues was detected after acidic hydrolysis followed by UHPLC analysis, which showed only a minor effect of heat treatment on protein oxidation in these protein systems.


Subject(s)
Milk Proteins , Proteomics , Chromatography, Liquid , Disulfides , Hot Temperature , Lactalbumin/chemistry , Lactoglobulins/chemistry , Milk Proteins/chemistry , Tandem Mass Spectrometry , Whey Proteins/analysis
19.
J Agric Food Chem ; 70(3): 847-856, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35025507

ABSTRACT

Disulfides are important for maintaining the protein native structure, but they may undergo rearrangement in the presence of free Cys residues, especially under elevated temperatures. Disulfide rearrangement may result in protein aggregation, which is associated with in vivo pathologies in organisms and in vitro protein functionality in food systems. In a food context, it is therefore important to understand the process of disulfide rearrangement on a site-specific level in order to control aggregation. In the present study, a liquid chromatography-mass spectrometry (LC-MS)-based bottom-up site-specific proteomic approach was optimized to study disulfide rearrangements in beta-lactoglobulin (ß-LG) under different heat treatments (60-90 °C). Artifactual disulfide rearrangement observed during sample preparation using a conventional protocol was detected and minimized by blocking the remaining free Cys residues with iodoacetamide in the presence of urea after heat treatment. Use of endoproteinase Glu-C for enzymatic hydrolysis allowed, for the first time, identification and comparison of the relative intensity of all theoretically possible ß-LG disulfide cross-links formed by the heat treatments. Non-native disulfides were formed from heat treatment at approx. 70 °C where ß-LG started to unfold, while higher levels of inter-molecular disulfide links were formed at ≥80 °C, in agreement with ß-LG aggregation detected by size exclusion chromatography analysis. Collectively, the Cys residues of the surface-located native disulfide Cys66-Cys160 were proposed to be more reactive, participating in heat-induced disulfide rearrangement, compared to other Cys residues. The abundant signal of non-native disulfide bonds containing Cys66, especially Cys66-Cys66, observed after heating suggested that Cys66 is a key disulfide-linked Cys residue in ß-LG participating in heat-induced inter-molecular disulfide bonds and the corresponding protein aggregation.


Subject(s)
Disulfides , Lactoglobulins , Chromatography, Liquid , Hot Temperature , Lactoglobulins/genetics , Mass Spectrometry , Proteomics
20.
J Agric Food Chem ; 70(1): 319-332, 2022 Jan 12.
Article in English | MEDLINE | ID: mdl-34967606

ABSTRACT

The most widely used whey protein ingredient in an infant formula (IF) is the whey protein concentrate (WPC). The processing steps used in the manufacturing of both a powdered IF and a WPC introduce protein modifications that may decrease the nutritional quality. A gently processed whey protein ingredient (serum protein concentrate; SPC) was manufactured and used for the production of a powdered IF. The SPC and the SPC-based IF were compared to the WPC and the powdered WPC-based IF. Structural protein modifications were evaluated, and Maillard reaction products, covering furosine, α-dicarbonyls, furans, and advanced glycation end products, were quantified in the IFs and their protein ingredients. IF processing was responsible for higher levels of protein modifications compared to the levels observed in the SPC and WPC. Furosine levels and aggregation were most pronounced in the WPC, but the SPC contained a high level of methylglyoxal, revealing that other processing factors should be considered in addition to thermal processing.


Subject(s)
Infant Formula , Maillard Reaction , Humans , Powders , Whey Proteins
SELECTION OF CITATIONS
SEARCH DETAIL
...