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1.
Food Chem ; 367: 130658, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343808

RESUMO

Camel milk is rich in nutrients and its impact on human medicine and nutrition cannot be ignored. We conducted an in-depth analysis of milk proteins obtained from two camel breed (Camelus bactrianus, CB and Camelus dromedarius, CD). Label-free proteomic technology was performed to analysis the MFGM and whey proteomes of CB and CD milk. In total, 1133 MFGM proteins and 627 whey proteins were identified from camel milk. Results revealed that 216 MFGM proteins and 109 whey proteins were significantly different between them. In addition, the cellular process, cell and binding were the predominately GO annotations of milk proteins. KEGG analysis shown that most proteins were involved in metabolic pathways. Furthermore, many proteins were found to be involved in PI3K/AKT signaling pathway, which could be the possible reason for hypoglycemic effect of camel milk. These results could provide a further understanding for unique biological characteristics of camel milk proteins.


Assuntos
Camelus , Proteoma , Animais , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Proteínas do Leite , Fosfatidilinositol 3-Quinases , Proteômica , Soro do Leite , Proteínas do Soro do Leite
2.
Food Chem ; 368: 130820, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34416488

RESUMO

Two commercially available food grade fungal protease preparations (Fungal Protease 31,000 and Fungal Protease 60000) were found to hydrolyse bovine acid whey proteins but left the beta-lactoglobulin (ß-Lg) intact under the processing conditions used. Comparative analysis before and after hydrolysis of bovine acid whey, by 1D- and 2D-PAGE, RP-HPLC and intact-mass mass spectrometry showed that the ß-Lg remains intact and in high yield after hydrolysis by the fungal proteases. The ß-Lg could be separated from the whey protein peptide hydrolysate by ultrafiltration. Subjecting whey fraction to hydrolysis with the fungal protease preparations provides a procedure, under relatively mild conditions, to generate a highly enriched ß-Lg fraction. ß-Lg is recognised as a valued material in the food, pharmaceutical and cosmetic industries due to its properties such as gelling and foaming. The enriched ß-Lg preparation would also have application in areas such as nanoencapsulation.


Assuntos
Lactoglobulinas , Leite , Animais , Bovinos , Hidrólise , Proteínas do Leite , Peptídeo Hidrolases , Soro do Leite , Proteínas do Soro do Leite
3.
J Environ Manage ; 301: 113872, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607142

RESUMO

Effluent originating from cheese production puts pressure onto environment due to its high organic load. Therefore, the main objective of this work was to compare the influence of different process variables (transmembrane pressure (TMP), Reynolds number and feed pH) on whey protein recovery from synthetic and industrial cheese whey using polyethersulfone (PES 30 kDa) membrane in dead-end and cross-flow modes. Analysis on the fouling mechanistic model indicates that cake layer formation is dominant as compared to other pore blocking phenomena evaluated. Among the input variables, pH of whey protein solution has the biggest influence towards membrane flux and protein rejection performances. At pH 4, electrostatic attraction experienced by whey protein molecules prompted a decline in flux. Cross-flow filtration system exhibited a whey rejection value of 0.97 with an average flux of 69.40 L/m2h and at an experimental condition of 250 kPa and 8 for TMP and pH, respectively. The dynamic behavior of whey effluent flux was modeled using machine learning (ML) tool convolutional neural networks (CNN) and recursive one-step prediction scheme was utilized. Linear and non-linear correlation indicated that CNN model (R2 - 0.99) correlated well with the dynamic flux experimental data. PES 30 kDa membrane displayed a total protein rejection coefficient of 0.96 with 55% of water recovery for the industrial cheese whey effluent. Overall, these filtration studies revealed that this dynamic whey flux data studies using the CNN modeling also has a wider scope as it can be applied in sensor tuning to monitor flux online by means of enhancing whey recovery efficiency.


Assuntos
Queijo , Soro do Leite , Queijo/análise , Filtração , Membranas Artificiais , Redes Neurais de Computação , Proteínas do Soro do Leite
4.
Food Chem ; 370: 130931, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509939

RESUMO

The present research is part of an effort to create whey-based functional food. Previously, it was concluded that proteins and peptides in an encapsulation matrix contribute to mechanical properties of beads, fermentative activity, acid and bile tolerance, and the survival of probiotics during the simulated gastrointestinal condition. This research evaluates the effects of using whey protein concentrate and trypsin hydrolysate as components of a matrix for probiotic encapsulation on the antioxidant capacity of a beverage. Carrier with hydrolysate showed better encapsulation efficiency, spherical factor, and antioxidant capacity before and after fermentation compared to the carrier with non-hydrolyzed proteins. Hydrolysis of protein used for carrier formulation positively impacts the beverage's antioxidant properties and probiotic viability during 28 days of storage. Using proteins, especially peptides, as a matrix component achieved three objectives: protection of probiotics, enrichment of products with antioxidants, and neutralization of possible bitter taste (because the bitter tasting peptides are incorporated into the matrix and as such cannot contribute to the taste of the product) that bioactive peptides usually possess.


Assuntos
Probióticos , Soro do Leite , Alginatos , Antioxidantes , Bebidas/análise , Tripsina , Proteínas do Soro do Leite
5.
Int J Food Microbiol ; 361: 109444, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-34749186

RESUMO

"Torta del Casar" is a Spanish soft-ripened cheese made with sheep's raw milk and subjected to a short ripening process, which favors the growth of pathogenic microorganisms including Listeria monocytogenes. The development of strategies to control pathogens and minimize health risks associated with the presence of L. monocytogenes in these products is of great interest. In this regard, the anti-Listeria activity of a whey protein hydrolysate (ProH) alone or combined with six lactic acid bacteria strains isolated from cheese was evaluated in this study as a biocontrol strategy using a "Torta del Casar" cheese-based medium. The most active combinations of lactic acid bacteria assayed induced a reduction higher than two logarithmic units in the growth of L. monocytogenes (serotype 4b) compared to their respective control when they were co-inoculated in "Torta del Casar" cheese-based medium at 7 °C for 7 days. In addition, the observed downregulation of some key virulence genes of L. monocytogenes suggests that the strain Lactiplantibacillus plantarum B2 alone and combined with the strain Lactiplantibacillus spp. B4 are good candidates to be used as biocontrol agents against L. monocytogenes growth in traditional soft cheeses based on raw milk during their storage at refrigeration temperatures.


Assuntos
Anti-Infecciosos , Queijo , Lactobacillales , Listeria monocytogenes , Animais , Queijo/análise , Microbiologia de Alimentos , Hidrolisados de Proteína , Ovinos , Virulência , Soro do Leite
6.
Clin Nutr ESPEN ; 45: 426-432, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34620350

RESUMO

BACKGROUND & AIMS: Weight loss in older adults enhances physical function, but may lead to sarcopenia and osteoporosis. Whey protein is a low cost rich source of essential amino acids, may improve physical function. We evaluated the feasibility and acceptability of consuming whey protein in the context of a weight-loss intervention in older adults with obesity. METHODS: A 12-week pilot feasibility, non-randomized weight loss study of 28 older adults was conducted, consisting of individualized, weekly dietitian visits with twice weekly physical therapist-led group strengthening classes. Half consumed whey protein, three times weekly, following exercise. Preliminary efficacy measures of body composition, sit-to-stand, 6-min walk and grip strength and subjective measures of self-reported health and function were also evaluated. RESULTS: Of the 37 enrolled, 28 completed the study (50 % in the protein group). Attendance rates for protein vs. non-protein groups were 89.9 ± 11.1 % vs. 95.6 ± 3.4 % (p = 0.08). Protein consumption was high in those attending classes (90.3 %) as was compliance at home (82.6 %). Whey was pleasant (67.3 ± 22.1, range 30-100, above average), had little aftertaste, and was neither salty or sticky. All were compliant (0.64 ± 0.84, range 0-5, low = higher compliance). Both groups lost significant weight (protein vs. no protein, -3.45 ± 2.86 vs. -5.79 ± 3.08, p = 0.47); Sit-to-stand, 6-min walk, and gait speed were no different, grip strength was improved in the protein compared to the non-protein group (-2.63 kg vs. 4.29 kg; p < 0.001). CONCLUSIONS: Our results suggest that whey protein is a low-cost and readily available nutritional supplement that can be integrated into a weight loss intervention.


Assuntos
Perda de Peso , Soro do Leite , Idoso , Suplementos Nutricionais , Estudos de Viabilidade , Humanos , Proteínas do Soro do Leite
7.
J Food Sci ; 86(11): 4914-4921, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34636031

RESUMO

Emulsifying capacity (EC) of proteins is a benchmark standard widely used to evaluate the quality of protein ingredients in emulsion foods. EC (mL of oil emulsified per g of protein) is usually measured by a sudden drop in electrical resistance (phase transition) with the continuous addition of oil to a specific protein solution. However, little is known about electrochemical mechanisms behind this process because resistance, measured with an ohmmeter, is not sensitive enough to monitor changes in the concentration of protein electrolytes. Here, pea (PPI), myofibrillar (MPI), and whey (WPI) protein isolates were vigorously homogenized with oil at a series of oil/protein ratios to prepare emulsions with different final protein concentrations. The conductivity was closely monitored using a conductivity meter. A linear relationship was discovered between conductivity and the final protein concentrations. At higher oil fractions, the migration of proteins from the aqueous phase to the oil-water interface limited protein mobility, leading to a conductivity drop. EC was calculated from the regression lines; when the starting protein concentration was raised from 0.5% to 2.0%, the EC of PPI, MPI, and WPI decreased from 717, 782, 1339 to 219, 303, and 540 mL oil/g protein, respectively. The dependence of EC on the initial protein concentration and the sensitivity of conductivity to the depleting protein electrolytes suggest that protein concentration is an important factor to consider when determining EC for a given protein or comparing EC among different proteins. PRACTICAL APPLICATION: The simple and sensitive electrical conductivity test described in this paper allows for the accurate determination of emulsifying capacity of proteins. It may be adopted by the food industry to compare the emulsifying properties of different protein ingredients.


Assuntos
Água , Soro do Leite , Condutividade Elétrica , Emulsificantes , Emulsões , Proteínas do Soro do Leite
8.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684821

RESUMO

Currently, there is a growing demand for flavorings, especially of natural origin. It is worth paying attention to the biotechnological processes of flavor production, characterized by simplicity, high efficiency and relatively low cost. In this study, we analyzed the ability of the Galac tomyces geotrichum mold to transform by-products of the dairy industry: sour whey and buttermilk to complex flavour mixtures with pleasant, honey-rose aroma. Furthermore, the aroma complexity of the fermentation product has been carefully identified applying a sensomic approach involving the use of gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and stable isotope dilution assay (SIDA) to identify and quantify aroma compounds. Based on the calculation of odor activity value (OAV), 13 key aroma compounds were present in both tested variants. The highest OAVs were found for phenylacetaldehyde (honey-like) in the buttermilk variant (912) and 2-phenylethanol (rose-like) in the sour whey variant (524). High values of this indicator were also recorded for phenylacetaldehyde (319) and 3-methyl-1-butanol with a fruity aroma (149) in the sour whey culture. The other compounds identified are 3-methylbutanal (malty), 2,3-butanedione (cheesy), isovaleric acid (cheesy), 3-(methylthio)-propanal (boiled potato), butanoic acid (vinegar), (E)-2-nonenal (fatty), ethyl furaneol (burnt sugar), dimethyl trisulfide (cabbage), and acetic acid (vinegar).


Assuntos
Leitelho/análise , Leitelho/microbiologia , Microbiologia de Alimentos , Geotrichum/metabolismo , Odorantes/análise , Soro do Leite/química , Soro do Leite/microbiologia , Acetaldeído/análogos & derivados , Acetaldeído/análise , Biotecnologia , Biotransformação , Fermentação , Aromatizantes/metabolismo , Tecnologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olfatometria , Álcool Feniletílico/análise , Paladar , Compostos Orgânicos Voláteis/análise
9.
J Dairy Sci ; 104(12): 12321-12331, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34600708

RESUMO

This study developed postbiotics with whey bioconversion product produced by Enterococcus faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and Lactococcus lactis ssp. lactis CAU2013 KACC 81152BP to alleviate periodontitis (PD) and to improve gut health. The powdered whey bioconversion product (EF) produced by E. faecalis M157 KACC 81148BP, mixed whey bioconversion products (EF+LL) from E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP, and phosphate-buffered saline (PBS; control) were administered orally to PD-induced rats for 8 wk. Infiltration of inflammatory cells and epithelial proliferation in periodontal tissue were found in control, but the lesions were reduced in PD+EF group (administration of EF to PD-induced rats), and no lesions were observed in PD+EF+LL group (administration of EF+LL to PD-induced rats). The bone loss volumes in PD+EF and PD+EF+LL groups were lower than in control. Cytokine production levels related to inflammation were lower and antioxidative stress markers were higher in PD+EF and PD+EF+LL groups than in control for both periodontal tissue and gut. The ratios of Lactobacillus spp. in gut microbiome of PD+EF and PD+EF+LL groups were higher than in control. These results indicate that the whey bioconversion product produced by E. faecalis M157 KACC 81148BP, and mixed whey bioconversion products produced by E. faecalis M157 KACC 81148BP and L. lactis CAU2013 KACC 81152BP are effective on relieving periodontitis and improving the gut health.


Assuntos
Microbioma Gastrointestinal , Lactococcus lactis , Doenças Periodontais , Doenças dos Roedores , Animais , Enterococcus faecalis , Doenças Periodontais/veterinária , Ratos , Soro do Leite
10.
Nutrients ; 13(9)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34578990

RESUMO

Specific partially hydrolysed whey-based infant formulas (pHF-W) have been shown to decrease the risk of atopic dermatitis (AD) in infants. Historically, AD has been associated primarily with milk allergy; however, defective skin barrier function can be a primary cause of AD. We aimed to ascertain whether oral supplementation with pHF-W can improve skin barrier function. The effect of pHF-W was assessed on transepidermal water loss (TEWL) and antibody productions in mice epicutaneously exposed to Aspergillus fumigatus. Human primary keratinocytes were stimulated in vitro, and the expression of genes related to skin barrier function was measured. Supplementation with pHF-W in neonatal mice led to a significant decrease in TEWL and total IgE, but not in allergen-specific antibody levels. The whey hydrolysate was sufficient to decrease both TEWL and total IgE. Aquaporin-3 gene expression, linked with skin hydration, was modulated in the skin of mice and human primary keratinocytes following protein hydrolysate exposure. Skin barrier improvement may be an additional mechanism by which pHF-W may potentially reduce the risk of AD development in infants. Further human studies are warranted to confirm the clinical efficacy of these observations.


Assuntos
Dermatite Atópica/prevenção & controle , Suplementos Nutricionais , Pele/efeitos dos fármacos , Proteínas do Soro do Leite/farmacologia , Soro do Leite/administração & dosagem , Animais , Animais Recém-Nascidos , Aquaporina 3/metabolismo , Humanos , Hidrólise , Imunoglobulina E/efeitos dos fármacos , Lactente , Fórmulas Infantis , Recém-Nascido , Queratinócitos/efeitos dos fármacos , Camundongos , Pele/metabolismo , Perda Insensível de Água/efeitos dos fármacos
11.
Nutrients ; 13(9)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34578889

RESUMO

Human clinical trials have shown that a specific partially hydrolyzed 100% whey-based infant formula (pHF-W) reduces AD risk in the first yeast of life. Meta-analyses with a specific pHF-W (pHF-W1) confirm a protective effect while other meta-analyses pooling different pHF-W show conflicting results. Here we investigated the molecular composition and functional properties of the specific pHF-W1 as well as the stability of its manufacturing process over time. This specific pHF-W1 was compared with other pHF-Ws. We used size exclusion chromatography to characterize the peptide molecular weight (MW), a rat basophil degranulation assay to assess the relative level of beta-lactoglobulin (BLG) allergenicity and a preclinical model of oral tolerance induction to test prevention of allergic sensitization. To analyze the exact peptide sequences before and after an HLA binding assay, a mass cytometry approach was used. Peptide size allergenicity and oral tolerance induction were conserved across pHF-W1 batches of production and time. The median MW of the 37 samples of pHF-W1 tested was 800 ± 400 Da. Further oral tolerance induction was observed using 10 different batches of the pHF-W1 with a mean reduction of BLG-specific IgE levels of 0.76 log (95% CI = -0.95; -0.57). When comparing pHF-W1 with three other formulas (pHF-W2 3 and 4), peptide size was not necessarily associated with allergenicity reduction in vitro nor oral tolerance induction in vivo as measured by specific IgE level (p < 0.05 for pHF-W1 and 2 and p = 0.271 and p = 0.189 for pHF-W3 and 4 respectively). Peptide composition showed a limited overlap between the formulas tested ranging from 11.7% to 24.2%. Furthermore nine regions in the BLG sequence were identified as binding HLA-DR. In conclusion, not all pHF-Ws tested have the same peptide size distribution decreased allergenicity and ability to induce oral tolerance. Specific peptides are released during the different processes used by different infant formula producers.


Assuntos
Alérgenos , Fórmulas Infantis/análise , Lactoglobulinas , Hipersensibilidade a Leite , Peptídeos , Proteínas do Soro do Leite , Alérgenos/imunologia , Animais , Cromatografia , Dermatite Atópica , Indústria Alimentícia , Alimentos Formulados , Humanos , Hidrólise , Imunoglobulina E , Lactente , Lactoglobulinas/análise , Lactoglobulinas/imunologia , Hipersensibilidade a Leite/prevenção & controle , Proteínas do Leite , Peso Molecular , Peptídeos/análise , Peptídeos/imunologia , Hidrolisados de Proteína/análise , Hidrolisados de Proteína/imunologia , Ratos Sprague-Dawley , Soro do Leite , Proteínas do Soro do Leite/análise , Proteínas do Soro do Leite/imunologia
12.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576173

RESUMO

Nowadays, probiotics have been proposed for substituting antibiotics in animal feed since the European Union banned the latter compounds in 2006 to avoid serious side effects on human health. Therefore, this work aimed to produce a probiotic product for use in animal feed by fed-batch fermentation of whey with a combination of kefir grains, AGK1, and the fermented whole milk used to activate these kefir grains. The probiotic culture obtained was characterized by high levels of biomass (8.03 g/L), total viability (3.6 × 108 CFU/mL) and antibacterial activity (28.26 Activity Units/mL). Some probiotic properties of the probiotic culture were investigated in vitro, including its survival at low pH values, under simulated gastrointestinal conditions, after freezing in skim milk at -20 °C, and in the commercial feed during storage at room temperature. The viable cells of lactic and acetic acid bacteria and yeasts exhibited higher tolerance to acidic pH and simulated gastrointestinal conditions when the cells were protected with skim milk and piglet feed, compared with washed cells. The results indicated the feasibility of producing a probiotic product at a low cost with a potential application in animal feed.


Assuntos
Kefir , Probióticos , Ração Animal , Animais , Fermentação/fisiologia , Temperatura , Soro do Leite/metabolismo
13.
Anim Sci J ; 92(1): e13618, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34409709

RESUMO

The first secretion, 24-h post parturition of the mammary glands of sows, known as colostrum, is high in protein and low in lactose and fat. As a consequence of an insufficient ingestion of colostrum, more than 50% of piglets fail to reach weaning and die. The composition and some functions of colostrum have been previously reported. For example, colostrum carbohydrates consist of mainly lactose. Lipids in the colostrum are mostly triacylglycerols, but <1% is fatty acids, which may act as homeostasis regulators. Similarly, proteins are found mostly as casein and whey, the latter being ≥80% immunoglobulins. Colostrum-derived immunoglobulins and bioactive proteins such as azurocidin help the immune system of the piglet fend off infections. In addition, leukocytes and exosomes are other minor but nonetheless equally crucial bioactive components in the porcine colostrum. Modern pig farming has achieved increases in pig productivity and litter size, but this has been accomplished in detriment of the health and the survival rate of piglets. Therefore, porcine colostrum is now even more important in pig farming. In the present review, we discuss the current knowledge on the composition and physiological functions of the porcine colostrum and briefly propose future research directions.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Caseínas/análise , Colostro/imunologia , Colostro/metabolismo , Dieta/veterinária , Lactose/análise , Suínos/imunologia , Suínos/metabolismo , Triglicerídeos/análise , Animais , Animais Recém-Nascidos , Peptídeos Catiônicos Antimicrobianos/análise , Proteínas Sanguíneas/análise , Colostro/citologia , Colostro/fisiologia , Exossomos , Feminino , Humanos , Imunoglobulinas/análise , Lactente , Leucócitos , Tamanho da Ninhada de Vivíparos , Parto , Desmame , Soro do Leite
14.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443426

RESUMO

Proteomics and metabolomics are analytic tools used in combination with bioinformatics to study proteins and metabolites which contribute to describing complex biological systems. The growing interest in research concerning the resolution of these systems has stimulated the development of sophisticated procedures and new applications. This paper introduces the evolution of statistical techniques for the treatment of data, suggesting the possibility to successfully characterize the milk-whey syneresis process by applying two-dimensional correlation analysis (2DCOR) to a series of CE electropherograms referring to milk-whey samples collected during cheese manufacturing. Two cheese-making processes to produce hard cheese (Grana type) and fresh cheese (Crescenza) were taken as models. The applied chemometric tools were shown to be useful for the treatment of data acquired in a systematically perturbed chemical system as a function of time.


Assuntos
Ácidos/análise , Queijo/análise , Leite/química , Nitrogênio/análise , Soro do Leite/química , Animais , Eletroforese Capilar , Projetos Piloto
15.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361782

RESUMO

Thermal treatments of milk induce changes in the properties of milk whey proteins. The aim of this study was to investigate the specific changes related to nutrients in the whey proteins of dairy cow milk after pasteurization at 85 °C for 15 s or ultra-high temperature (UHT) at 135 °C for 15 s. A total of 223 whey proteins were confidently identified and quantified by TMT-based global discovery proteomics in this study. We found that UHT thermal treatment resulted in an increased abundance of 17 proteins, which appeared to show heat insensitivity. In contrast, 15 heat-sensitive proteins were decreased in abundance after UHT thermal treatment. Some of the heat-sensitive proteins were connected with the biological immune functionality, suggesting that UHT thermal treatment results in a partial loss of immune function in the whey proteins of dairy cow milk. The information reported here will considerably expand our knowledge about the degree of heat sensitivity in the whey proteins of dairy cow milk in response to different thermal treatments and offer a knowledge-based reference to aid in choosing dairy products. It is worth noting that the whey proteins (lactoperoxidase and lactoperoxidase) in milk that were significantly decreased by high heat treatment in a previous study (142 °C) showed no significant difference in the present study (135 °C). These results may imply that an appropriately reduced heating intensity of UHT retains the immunoactive proteins to the maximum extent possible.


Assuntos
Leite/química , Pasteurização/métodos , Proteínas do Soro do Leite/química , Soro do Leite/química , Animais , Feminino , Temperatura Alta , Leite/imunologia , Anotação de Sequência Molecular , Estabilidade Proteica , Proteômica/métodos , Soro do Leite/imunologia , Proteínas do Soro do Leite/classificação , Proteínas do Soro do Leite/imunologia , Proteínas do Soro do Leite/isolamento & purificação
16.
Bioresour Technol ; 341: 125739, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34418846

RESUMO

ß-Farnesene can replace petroleum products as specialty fuel to solve the global fuel energy crisis, but its production by Escherichia coli (E.coli) using glucose and isopropyl ß-D-1-thiogalactopyranoside (IPTG) is costly. Hence, we developed a new strategy to produce ß-farnesene by engineered E.coli strain F13 with bifunctional utilization of whey powder. The utilization of whey powder as a substrate ensured the growth of the strain F13, while whey powder could also replace IPTG to induce the production of ß-farnesene. In shake flasks, ß-farnesene production reached 2.41 g/L by the bifunctional utilization of whey powder as a substrate and inducer, 65.1% higher than that with IPTG and glucose. In the 7 L bioreactor, ß-farnesene production reached 4.74 g/L using whey powder, which was 197% of that in shake flasks. Therefore, this new strategy might be an attractive route to broaden the applications of whey powder and achieve the economical production of ß-farnesene.


Assuntos
Escherichia coli , Sesquiterpenos , Pós , Soro do Leite
17.
J Dairy Sci ; 104(10): 10500-10512, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34334199

RESUMO

In the manufacture of cream cheese, sweet cream and milk are blended to prepare the cream cheese mix, although other ingredients such as condensed skim milk and skim milk powder may also be included. Whey cream (WC) is an underutilized fat source, which has smaller fat droplets and slightly different chemical composition than sweet cream. This study investigated the rheological and textural properties of cream cheeses manufactured by substituting sweet cream with various levels of WC. Three different cream cheese mixes were prepared: control mix (CC; 0% WC), cream cheese mixes containing 25% WC (25WC; i.e., 75% sweet cream), and cream cheese mixes with 75% WC (75WC; i.e., 25% sweet cream). The CC, 25WC, and 75WC mixes were then used to manufacture cream cheeses. We also studied the effect of WC on the initial step in cream cheese manufacture (i.e., the acid gelation process monitored using dynamic small amplitude rheology). Acid gels were also prepared with added denatured whey proteins or membrane proteins/phospholipids (PL) to evaluate how these components affected gel properties. The rheological, textural, and sensory properties of cream cheeses were also measured. The WC samples had significantly higher levels of PL and insoluble protein compared with sweet cream. An increase in the level of WC reduced the rate of acid gel development, similar to the effect of whey phospholipid concentrate added to mixes. In cream cheese, an increase in the level of added WC resulted in significantly lower storage modulus values at temperatures <20°C. Texture results, obtained from instrumental and sensory analyses, showed that high level of WC resulted in significantly lower firmness or hardness values and higher stickiness compared with cream cheeses made with 25WC or CC cream cheeses. The softer, less elastic gels or cheeses resulting from the use of high levels of WC are likely due to the presence of components such as PL and proteins from the native milk fat globule membrane. The use of low levels of WC in cream cheese did not alter the texture, whereas high levels of WC could be used if manufacturers want to produce more spreadable products.


Assuntos
Queijo , Animais , Queijo/análise , Manipulação de Alimentos , Leite , Reologia , Soro do Leite , Proteínas do Soro do Leite
18.
J Dairy Sci ; 104(11): 11401-11412, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454763

RESUMO

Acid whey, a byproduct of Greek yogurt production, has little commercial value due to its low protein content and is also environmentally harmful when disposed of as waste. However, as a product of microbial fermentation, acid whey could be a rich source of beneficial metabolites associated with fermented foods. This study increases understanding of acid whey composition by providing a complete metabolomic profile of acid whey. Commercial and laboratory-made Greek yogurts, prepared with 3 different bacterial culture combinations, were evaluated. Samples of uncultured milk and cultured whey from each batch were analyzed. Ultra-high-performance liquid chromatography-tandem mass spectrometry metabolomics were used to separate and identify 477 metabolites. Compared with uncultured controls, acid whey from fermented yogurt showed decreases in some metabolites and increases in others, presumably due to the effects of microbial metabolism. Additional metabolites appeared in yogurt whey but not in the uncultured control. Therefore, the effect of microbial fermentation is complex, leading to increases or decreases in potentially bioactive bovine metabolites while generating new microbial compounds that may be beneficial. Metabolite production was significantly affected by combinations of culturing organisms and production location. Differences between laboratory-made and commercial samples could be caused by different starting ingredients, environmental factors, or both.


Assuntos
Soro do Leite , Iogurte , Animais , Bovinos , Fermentação , Metabolômica , Leite , Proteínas do Soro do Leite
19.
Waste Manag ; 132: 31-43, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34304020

RESUMO

Cheese whey (CW) is the main by-product of the dairy industry and is often considered one of the main agro-industrial biowaste streams to handle, especially within the European Union, where the diary activities play an essential role in the agrarian economy. In the paper, Life Cycle Assessment (LCA) is used to analyse the feasibility of producing polyhydroxyalkanoates (PHA) as the main output of an innovative CW valorisation route which is benchmarked against a conventional anaerobic digestion (AD) process. To this aim, the LCA inventory data are derived from lab-scale PHA accumulation tests performed on real CW, while data from the literature of concern are used for modelling both the PHA extraction from the accumulating biomass and for the alternative CW valorisation through AD. The comparison shows that AD would have better environmental performances than the baseline PHA production scenario. For example, the climate change indicator values result 44.8 and -35.7 kg CO2 eq./t CW for the baseline PHA recovery and AD, respectively. LCA proved to be a useful tool to highlight the weak points of innovative processes and suggest proper improvements. Once improved and again analysed through the LCA, the PHA production process from CW shows that environmental performance comparable to AD may be achieved. With reference, again, to the climate change indicator the value can be reduced to -50.3 kg CO2 eq./t CW for the improved PHA production process.


Assuntos
Queijo , Poli-Hidroxialcanoatos , Animais , Biomassa , Reatores Biológicos , Estágios do Ciclo de Vida , Soro do Leite
20.
Nutrients ; 13(7)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199006

RESUMO

People experiencing sleep problems may benefit from nutrients supporting serotonin metabolism and stress reduction. We studied the effect of a dairy-based product (DP) containing protein, galacto-oligosaccharides, vitamins and minerals, on sleep quality, stress, and gut-microbiota. In a cross-over RCT (three weeks intervention; three weeks washout), adults (n = 70; 30-50 y) with sleep disturbances (Pittsburgh Sleep Quality Index (PSQI) ≥ 9) consumed products 1 h before bed-time. Sleep quality (PSQI) was measured weekly, stress at base- and end-line (Depression Anxiety Stress Scale and saliva cortisol). Fecal samples were collected in the 1st intervention period only. Compared to placebo (skimmed milk), PSQI was only lower at day 14 in the 2nd intervention period in intention-to-treat (ITT) (p = 0.017; n = 69) and per-protocol (PP) (p = 0.038; n = 64) analyses. Post-hoc analysis (modified-PP: n=47, with baseline PSQI ≥ 9, and endline day 14), however, showed a decrease in PSQI (-1.60 ± 2.53; p = 0.034). Early morning saliva cortisol decreased versus placebo (p = 0.045). Relative abundance of Bifidobacterium increased (p = 0.02). Redundancy analysis showed an inverse relationship between baseline microbiota composition and baseline PSQI (p = 0.046). Thus, although DP did not improve sleep quality in ITT and PP populations, it did in the modPP. DP reduced salivary cortisol and stimulated Bifidobacterium, which possibly is important for sleep improvement.


Assuntos
Microbioma Gastrointestinal/fisiologia , Oligossacarídeos/uso terapêutico , Transtornos do Sono-Vigília/dietoterapia , Sono/efeitos dos fármacos , Proteínas do Soro do Leite/uso terapêutico , Adulto , Bifidobacterium/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Fezes/microbiologia , Feminino , Humanos , Masculino , Triptofano , Soro do Leite
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