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1.
Chemosphere ; 259: 127474, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32603962

RESUMO

Anaerobic digestion (AD) is the biological preferred treatment applied to Slaughterhouse wastewaters (SWW) due to its effectiveness. The aim of the study is to investigate the effect of different percentages of fats, oil and grease (FOG) on biomethane production in anaerobic co-digestion with slaughterhouse wastewater using BMP tests under mesophilic conditions (35 °C). For this purpose, three percentages of FOG from 1% to 10% were tested. Biodegradability, biomethane production and the microbial population were studied. In addition, settling capacity has been evaluated at different conditions: i) before and after anaerobic co-digestion; ii) at different temperature 25 °C and 35 °C. The settling rates as well as the characterization of the digestate were recorded. Experimental results showed that all the co-digestion mixtures (FOG percentages = 1-10%) enhanced biomethane production and biodegradability compared to AD of sole SWW. The best conditions were achieved at 5-10% of FOG, showing biodegradability of 66-70% CODtremoval and specific biomethane productions of 562 and 777 mLCH4·g-1CODsremoved, respectively. Regarding microbial dynamics, Eubacteria was reduced with the increase in %FOG but Acetate utilizing methanogens was increased. Regarding settling capacity, mesophilic temperatures (35 °C) increased the settling rate of digestate in 1.76 times and reduced the lag-phase to 0.92 min; obtaining a more concentrated sludge and leaving a clarified whose TSS represent only 8% of TS.


Assuntos
Matadouros , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Anaerobiose , Bactérias , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Gorduras , Hidrocarbonetos , Metano , Esgotos/química
2.
Food Chem ; 332: 127327, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615380

RESUMO

The effect of variation in acid gel pH during cream cheese production was investigated. The gel microstructure was denser and cheese texture firmer, as the pH decreased from pH 5.0 to pH 4.3, despite the viscoelasticity of these gels remaining similar during heating. Protein hydration and secondary structure appeared to be key factors affecting both cheese microstructure and properties. Proteins within the matrix appeared to swell at pH 5.0, leading to a larger corpuscular structure; greater ß-turn structure was also observed by synchrotron-Fourier transform infrared (S-FTIR) microspectroscopy and the cheese was softer. A decrease in pH led to a denser microstructure with increased aggregated ß-sheet structure and a firmer cheese. The higher whey protein loss at low pH likely contributed to increased cheese hardness. In summary, controlling the pH of acid gel is important, as this parameter affects proteins in the cheese, their secondary structure and the resulting cream cheese.


Assuntos
Queijo/análise , Gorduras/química , Manipulação de Alimentos , Proteínas/química , Reologia , Concentração de Íons de Hidrogênio , Viscosidade
3.
J Sports Med Phys Fitness ; 60(4): 618-624, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32396288

RESUMO

BACKGROUND: The purpose of this study was to compare the effects of a 24-week resistance-training (RT) program performed 2 vs. 3 times per week on body fat and metabolic health markers in older women. METHODS: Thirty-nine women (≥60 years old) were randomly assigned to two groups according to RT frequency (G2x=two sessions per week, N.=19; and G3x=three sessions per week, N.=20) and were submitted to two 12-week stages of whole-body RT. In the first stage, participants performed 1 set of 10 to 15 repetitions in each of eight exercises, whereas in the second stage, they performed 2 sets of 10 to 15 repetitions. Body fat was estimated by DXA, while biochemical analyses were performed on venous blood samples collected in the morning hours after a 12 hours' fasting and after a minimum of 48 hours since the last physical exercise session. RESULTS: After the 24 weeks of RT, only G3x significantly reduced body fat mass (G2x=0.0%; G3x=-5.1%), whereas both G2x and G3x reduced blood glucose and C-reactive protein levels. Both groups improved HDL-C after the first 12-week stage compared to baseline, although the changes from pre- to post-training were not significantly different between groups. No significant difference was observed compared to baseline for total cholesterol, VLDL-C, LDL-C, and triglycerides for either group. CONCLUSIONS: These results suggest that RT-induced changes in health markers may occur regardless of RT frequency, whereas performing RT three times per week may be needed for reducing total body fat mass in older women.


Assuntos
Gorduras/metabolismo , Obesidade/terapia , Treinamento de Resistência , Tecido Adiposo/metabolismo , Idoso , Biomarcadores/sangue , Composição Corporal , Terapia por Exercício , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Obesidade/sangue , Triglicerídeos/sangue
4.
Am J Clin Nutr ; 111(6): 1178-1189, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412597

RESUMO

BACKGROUND: There is convincing evidence that daily whole almond consumption lowers blood LDL cholesterol concentrations, but effects on other cardiometabolic risk factors such as endothelial function and liver fat are still to be determined. OBJECTIVES: We aimed to investigate whether isoenergetic substitution of whole almonds for control snacks with the macronutrient profile of average snack intakes, had any impact on markers of cardiometabolic health in adults aged 30-70 y at above-average risk of cardiovascular disease (CVD). METHODS: The study was a 6-wk randomized controlled, parallel-arm trial. Following a 2-wk run-in period consuming control snacks (mini-muffins), participants consumed either whole roasted almonds (n = 51) or control snacks (n = 56), providing 20% of daily estimated energy requirements. Endothelial function (flow-mediated dilation), liver fat (MRI/magnetic resonance spectroscopy), and secondary outcomes as markers of cardiometabolic disease risk were assessed at baseline and end point. RESULTS: Almonds, compared with control, increased endothelium-dependent vasodilation (mean difference 4.1%-units of measurement; 95% CI: 2.2, 5.9), but there were no differences in liver fat between groups. Plasma LDL cholesterol concentrations decreased in the almond group relative to control (mean difference -0.25 mmol/L; 95% CI: -0.45, -0.04), but there were no group differences in triglycerides, HDL cholesterol, glucose, insulin, insulin resistance, leptin, adiponectin, resistin, liver function enzymes, fetuin-A, body composition, pancreatic fat, intramyocellular lipids, fecal SCFAs, blood pressure, or 24-h heart rate variability. However, the long-phase heart rate variability parameter, very-low-frequency power, was increased during nighttime following the almond treatment compared with control (mean difference 337 ms2; 95% CI: 12, 661), indicating greater parasympathetic regulation. CONCLUSIONS: Whole almonds consumed as snacks markedly improve endothelial function, in addition to lowering LDL cholesterol, in adults with above-average risk of CVD.This trial was registered at clinicaltrials.gov as NCT02907684.


Assuntos
Doenças Cardiovasculares/metabolismo , LDL-Colesterol/sangue , Endotélio Vascular/fisiopatologia , Gorduras/metabolismo , Fígado/metabolismo , Prunus dulcis/metabolismo , Adulto , Idoso , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nozes/metabolismo , Fatores de Risco , Lanches , Triglicerídeos/sangue , Vasodilatação
5.
Food Chem ; 322: 126636, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283375

RESUMO

Inter-relationship between lactose crystallization (LC), the amount and composition of surface free fat (SFF); and their effect on physico-chemical properties of infant formula (IF) containing hydrolyzed and intact (non-hydrolyzed) whey protein in their composition were investigated at two temperatures (25 and 45 °C) and five RH (11-65%) conditions. Results varied with compositional variation of IF. LC increased exponentially with SFF in non-hydrolyzed IF powders. IF composition influenced LC and caused selective migration of triglycerides, resulting in higher proportion of unsaturated fats in SFF of powders with large lactose crystals and vice-versa. Increase in SFF with increased proportion of saturated fats in their composition, resulted in reduced wettability of powders. Overall, IF composition affects LC which influences the amount and type of fat migration to particle surface resulting in varying wettability of IF powders.


Assuntos
Gorduras/química , Fórmulas Infantis/química , Lactose/química , Cristalização , Armazenamento de Alimentos , Pós/química , Temperatura , Molhabilidade , Proteínas do Soro do Leite/química
6.
Clin Sci (Lond) ; 134(8): 1031-1048, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32337536

RESUMO

Global trends in the prevalence of overweight and obesity put the adipocyte in the focus of huge medical interest. This review highlights a new topic in adipose tissue biology, namely the emerging pathogenic role of fat accumulation in bone marrow (BM). Specifically, we summarize current knowledge about the origin and function of BM adipose tissue (BMAT), provide evidence for the association of excess BMAT with diabetes and related cardiovascular complications, and discuss potential therapeutic approaches to correct BMAT dysfunction. There is still a significant uncertainty about the origins and function of BMAT, although several subpopulations of stromal cells have been suggested to have an adipogenic propensity. BM adipocytes are higly plastic and have a distinctive capacity to secrete adipokines that exert local and endocrine functions. BM adiposity is abundant in elderly people and has therefore been interpreted as a component of the whole-body ageing process. BM senescence and BMAT accumulation has been also reported in patients and animal models with Type 2 diabetes, being more pronounced in those with ischaemic complications. Understanding the mechanisms responsible for excess and altered function of BMAT could lead to new treatments able to preserve whole-body homeostasis.


Assuntos
Medula Óssea/metabolismo , Diabetes Mellitus/metabolismo , Gorduras/metabolismo , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Diabetes Mellitus/genética , Humanos
7.
Sci Total Environ ; 728: 138415, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32348944

RESUMO

Daily, sewage treatment works (STWs) receive large volumes of fats, oils and greases (FOG), by-products of food preparation. To increase FOG removal at STW, conventional primary sedimentation tanks (PSTs) can be enhanced using chemical coagulant or through dissolved air flotation (DAF) techniques. This work aimed to assess the potential benefits of enhanced primary treatment for FOG removal through an energy and costs analysis. To achieve this, a five-year sampling programme was conducted monthly at 15 STWs measuring FOG concentrations in crude and settled sewage (i.e. after primary treatment). In addition, two DAF pilot systems were trialled for four months and their performance, in terms of FOG removal, was assessed and compared to that of a control primary clarifier. Across the 15 STWs, influent FOG concentrations were found at 57 ±â€¯11 mg.L-1. Chemical coagulants dosed prior to PSTs increased FOG removal rates on average to 71% whilst traditional sedimentation only achieved 50% removal. Effluent FOG concentrations were found between 12-22 mg.L-1 and 19-36 mg.L-1 respectively. By contrast, DAF achieved FOG effluent concentrations on average at 10 ±â€¯4 mg.L-1 corresponding to 74% removal from a relatively low influent concentration of 40 ±â€¯30 mg.L-1. Thus, enhanced primary treatments have the potential to reduce organic load to secondary treatment and increase energy generation through anaerobic digestion. The overall net energy balance was estimated at 2269 MWh.year-1 for the DAF compared to 3445 MWh.year-1 for the chemically-enhanced PST making it a less financially attractive alternative. Yet, in the case where the works require upgrading to accommodate flow or load increases, DAF appeared as a sensible option over sedimentation offering significantly lower capital costs and footprint. In relation to FOG management, upgrading all STWs is not realistic and will require understanding where the benefits would be the highest.


Assuntos
Esgotos , Águas Residuárias , Gorduras , Hidrocarbonetos , Óleos Vegetais
8.
J Oleo Sci ; 69(3): 199-206, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115546

RESUMO

The wasted raw fat of chicken was extracted and recrystallized with slowly stir at various cooling temperature to get a clear out-looking and liquid chicken oil. The recovery percentage of liquid chicken oil is about 100, 87, 78, 49 and 0% at 25, 21, 17, 13 and 9°C. The chicken liquid oil has a new composition of fatty acids than the original oil (p < 0.05) and has a safety range in acid value and peroxide value. The fatty acid ratio of the liquid chicken oil obtained at 13°C to be 1:1.6:0.9 (SFA: MUFA: PUFA) is believed to be good dietary oil. The concept of ideal fatty acid ratio comes from Hayes' report (1:1.5:1, SFA: MUFA: PUFA) which is also found to mimic to human lipid fatty acid ratio. Statistically evaluation on Hayes' basis, it showed that the liquid chicken oil scored even better than the extra virgin olive oil. In conclusion, this study not only first open a new gate for the recycle of global raw chicken fat to a dietary oil but also give an evidence that the chicken oil seems more compatible to human lipid on the hypothetic basis of biocompatibility.


Assuntos
Gorduras Insaturadas na Dieta/isolamento & purificação , Gorduras/química , Animais , Galinhas , Gorduras Insaturadas/química , Ácidos Graxos/análise , Temperatura
9.
Food Chem ; 318: 126518, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32151925

RESUMO

Cocoa butter substitutes (CBS) used for chocolate preparation was produced using a mixture of palm kernel oil (PKO) and enzymatically interesterified fats. The interesterified fats consisted of palm olein (POL), fully hydrogenated palm oil (FHPO) and PKO that were catalyzed using Lipozyme TL IM at 65 °C in a solvent-free packed bed reactor. An interesterification degree of 97.10% was obtained using feed flow rate of 70 mL/min and the interesterified fats showed steep solid fat content (SFC) curve characteristics with low SFC at high temperature. In the binary system, PKO and the interesterified fats showed good compatibility at 5-10 °C, while eutectic effects were observed at 15-35 °C. CBS produced from PKO and the interesterified fats in a mass ratio of 4:6 (CBS-46) and 3:7 (CBS-37) had crystals formed prominently in the ß' form. Without the need of a tempering process, chocolate made using CBS-46 as the base oil exhibited the desired properties in terms of hardness and fracturability.


Assuntos
Chocolate , Gorduras na Dieta , Indústria de Processamento de Alimentos/métodos , Óleo de Palmeira/química , Catálise , Esterificação , Gorduras/química , Indústria de Processamento de Alimentos/instrumentação , Lipase/química
10.
J Food Sci ; 85(4): 964-971, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32222051

RESUMO

Oil migration (OM) has been an immense issue in fat-based foods such as peanut butter and chocolate fillings. The objective of this study was to evaluate the effect of high-intensity ultrasound (HIU) on OM in a palm kernel oil-based fat used in chocolate fillings, coatings, and confectionery applications. The sample was crystallized at 30 °C for 90 min and stored for 48 hr at 25 °C. HIU was applied after 20 min at 30 °C using a 3.2-mm diameter tip operating at an amplitude of 216 µm (90 W) for 10 s. OM was measured using a centrifuge- and a filter paper-based method. Crystal morphology and size, solid fat content (SFC), melting behavior, and hardness were evaluated after 90 min, 48 hr, and after OM. Results showed that HIU reduced OM (P < 0.05) by 52.0% when measured using the filter paper method while a reduction of 97.4% was observed when measured with the centrifuge method. HIU also reduced the crystal size (P < 0.05) and formed a more organized crystalline network. A reduction in peak temperature (Tp ) after 90 min of crystallization and 48 hr of storage was observed in sonicated samples without affecting the enthalpy. However, enthalpy and Tp were higher in the sample without HIU analyzed after OM due to the migration of low melting point triacylglycerols out of the crystalline network. HIU also increased the hardness (P < 0.05) from 1.37 N and 3.17 N. But no differences (P > 0.05) were found on SFC due to sonication. Overall, HIU changed the crystalline structure of the fat allowing for a better entrapment of liquid oil in the crystalline matrix. Results from this study will benefit food producers that are looking for fat sources with better capacity to entrap oil. PRACTICAL APPLICATION: OM is one of the main problems facing the fat industry, especially since the elimination of partially hydrogenated fats from foods. Efforts are being focused on finding new technologies to reduce OM and therefore to improve the shelf life of the product. This study introduces for the first time, a new processing technology to reduce OM in a palm kernel fat with high content of saturated fatty acids that is commonly used in confectionery applications.


Assuntos
Manipulação de Alimentos/métodos , Óleo de Palmeira/química , Sonicação/métodos , Cristalização , Gorduras/química , Ácidos Graxos/química , Dureza , Cinética , Sementes/química , Temperatura , Triglicerídeos/química
11.
Nat Commun ; 11(1): 1418, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184397

RESUMO

The Golgi apparatus plays a central role in the intracellular transport of macromolecules. However, molecular mechanisms of Golgi-mediated lipid transport remain poorly understood. Here, we show that genetic inactivation of the Golgi-resident protein GRASP55 in mice reduces whole-body fat mass via impaired intestinal fat absorption and evokes resistance to high-fat diet induced body weight gain. Mechanistic analyses reveal that GRASP55 participates in the Golgi-mediated lipid droplet (LD) targeting of some LD-associated lipases, such as ATGL and MGL, which is required for sustained lipid supply for chylomicron assembly and secretion. Consequently, GRASP55 deficiency leads to reduced chylomicron secretion and abnormally large LD formation in intestinal epithelial cells upon exogenous lipid challenge. Notably, deletion of dGrasp in Drosophila causes similar defects of lipid accumulation in the midgut. These results highlight the importance of the Golgi complex in cellular lipid regulation, which is evolutionary conserved, and uncover potential therapeutic targets for obesity-associated diseases.


Assuntos
Gorduras/metabolismo , Proteínas da Matriz do Complexo de Golgi/genética , Obesidade/genética , Obesidade/prevenção & controle , Animais , Transporte Biológico , Dieta Hiperlipídica , Drosophila , Complexo de Golgi/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/metabolismo , Obesidade/fisiopatologia , Ganho de Peso
12.
Food Chem ; 315: 126281, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004984

RESUMO

Determination of the fatty acid (FA) profile of milk fat generally involves total lipid extraction from liquid milk, transesterification and GC analysis. The lipid extraction step is time consuming and often employs toxic solvents such as chloroform. Two alternative methods are presented here that skip the lipid extraction step and allow the determination of FA composition via direct transesterification of dried milk and liquid milk respectively. We have shown that dried milk can be used directly in alkaline-catalysed methylation, whereas direct transesterification of both dried milk and fresh milk is feasible with acidic methanol. Both methods generate similar results as compared to the classical two-step method (i.e. lipid extraction and FA methylation) when optimised methylation parameters (temperature, time, milk and reagent volume) are followed. By omitting the lipid extraction step, these simplified one-step methods offer a much higher throughput and a reduced cost in FA composition analysis of milk samples.


Assuntos
Gorduras/química , Ácidos Graxos/análise , Leite/química , Animais , Esterificação , Solventes
13.
Food Chem ; 316: 126305, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32066069

RESUMO

A fourth phase of water, labeled exclusion-zone or "EZ," extends from hydrophilic surfaces. Salient features include exclusion of colloidal and molecular solutes, and characteristic light absorbance at 270 nm. In cell systems, EZ water interfaces with membranes, macromolecules, and organelles, and its buildup appears to be vital for function. For years thought to build health, fats have gained a negative reputation over the last few decades. While their exact role in health remains unclear, now they have become more accepted. We tested several fats for their capacity to generate EZ water. Large EZs formed next to ghee, coconut oil, lard, organic clarified butter, and 'Brain Octane®' oil. Cold ghee surfaces produced especially large EZs. Thus, EZ growth, confirmed by microsphere exclusion and UV-VIS absorbance spectroscopy of samples flanking the fat, may be an important factor in cellular hydration and might well underlie the health-promoting function of fats.


Assuntos
Gorduras/química , Encéfalo , Química Encefálica , Interações Hidrofóbicas e Hidrofílicas , Temperatura , Água/química
14.
Int J Food Microbiol ; 320: 108543, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32028204

RESUMO

This study investigated the effect of growth conditions on proteolytic activity of six Pseudomonas strains, (Pseudomonas fragi DZ1, Pseudomonas koreensis DZ138, Pseudomonas rhodesiae DZ351, Pseudomonas fluorescens DZ390, Pseudomonas synxantha DZ832 and Pseudomonas lundensis DZ845), isolated from raw milk. The proteolytic activity of all Pseudomonas strains in dairy media (skim milk and whole milk) was significantly higher (p < 0.05) than in non-dairy media (TSB), with most activity from Pseudomonas grown in whole milk. The proteolytic activity from P. lundensis DZ845 grown in TSB with the addition of 5% (w/v) butter was higher than other dairy ingredients added to TSB and the amount of proteolytic activity increased with increasing concentrations of butter (from 5 to 15%). P. rhodesiae DZ351 showed little proteolytic activity in all TSB supplemented with dairy ingredients. Only four of the six strains produced one protease of 47 kDa when grown in TSB. However, all six strains were able to produce at least one type of proteases in milk medium. For P. lundensis DZ845, a 12% casein zymography gel revealed that the presence of butter could induce proteolytic activity. This is the first study showing the effect of milk fat (butter) on the proteolytic activity of Pseudomonas. This highlights the greater vulnerability of whole milk compared to skim milk to proteolytic activity.


Assuntos
Gorduras/análise , Leite/química , Leite/microbiologia , Pseudomonas/metabolismo , Animais , Caseínas/metabolismo , Peptídeo Hidrolases/metabolismo , Proteólise , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/isolamento & purificação , Especificidade da Espécie
16.
J Food Sci ; 85(2): 421-431, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31943214

RESUMO

Animal fat tissue (that is, pork or beef fat) is composed of liquid and solid fat incorporated in a network of connective tissue. Hence, their rheological and thermal properties may differ significantly from plant-derived fats. Specifically, animal fats have elastic and melting properties that give rise to not only a certain comminution behavior during processing, but also provide meat products such as sausages with certain organoleptic properties. To mimic key properties of animal fat tissue with plant-derived materials, a new structuring approach was used. Canola oil was mixed with <30% (w/w) of fully hydrogenated canola oil at 65 °C, hot-emulsified with a soy protein suspension (8%, w/w) at a lipid content of 70% (w/w) using a high-shear disperser, and cooled to 37 °C. The concentrated, emulsified fat crystal networks were then incubated with transglutaminase for 1 hr to induce protein crosslinking. Microscopy images showed that samples were composed of tightly packed lipid particles with regions of coalesced or unemulsified lipids appearing at higher solid fat concentrations. Texture analysis and rheological measurements showed that crosslinked samples possessed elasticities that decreased with increasing solid fat concentration. Above 30% solid fat, matrices reverted back to exhibiting a mainly plastic behavior. Results were attributed to the formation of either a droplet-filled protein network, a particulate fat crystal network, or a mixture thereof. Taken together, results show that plant-based crosslinked emulsified fat crystal networks are able to mimic mechanical properties of animal fat provided that not too much solid fat (<30% in this study) is used. This makes them useful for the manufacture of meat products or analogues. PRACTICAL APPLICATION: This study introduced a new structuring approach to mimic properties of animal fat tissue with only plant-derived materials. The structured lipids can, for example, be used for the manufacture of processed meat analogues.


Assuntos
Emulsificantes/química , Substitutos da Gordura/química , Produtos da Carne/análise , Óleo de Brassica napus/química , Tecido Adiposo/química , Animais , Bovinos , Emulsões/química , Gorduras/química , Manipulação de Alimentos , Proteínas de Soja/química , Suínos
17.
J Food Sci ; 85(2): 465-476, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31957899

RESUMO

The aim of the current study was to identify quality indicators of fat (14.50 ± 0.75%) and low-fat (4.79 ± 0.63%) raw ground beef by monitoring changes in physicochemical and microbiological parameters during aerobic refrigerated storage, such as water-holding capacity, pH, thiols, carbonyl compounds, thiobarbituric acid reactive substances (TBARS), metmyoglobin, deoxymyoglobin, oxymyoglobin color indices, pseudomonads, Brochothrix thermosphacta, and total viable counts. Meat packaged in air-permeable polyethylene plastic film was stored under controlled isothermal conditions (0, 5, 10, and 15 °C). A population level of pseudomonads equal to 7.0 ± 0.5 log10 colony forming units (CFU)/g was considered as the potential spoilage level. Using principal component analysis, samples were distinguished on the basis of their microbial load. A significant positive correlation between microbial population and carbonyls, metmyoglobin, TBARS, water-holding capacity, and a negative correlation with thiols and color parameters (L* , chroma) were observed. Two different approaches were followed to estimate the quality status of samples: (i) the partial least square (PLS) regression with R2 of 0.93 and root mean square error prediction of 0.44 for pseudomonads, using the above physicochemical characteristics as the dominant input variables, which allowed prediction of the microbiological status of ground beef regardless of time-temperature storage profile and fat content, and (ii) a square-root-type model (adjusted R2 of 0.952) that satisfactorily predicted the growth of spoilage pseudomonads under isothermal and dynamic conditions, regardless of the above physicochemical changes. The above results suggest that depending on the available input data, the two modeling approaches can accurately (and complementarily) assess quality of aerobically stored ground beef. PRACTICAL APPLICATION: Changes in appearance and quality of fat and low-fat raw ground beef are associated with physicochemical alteration and/or microbial growth. The study provides two different modeling approaches that can be integrated in an intelligent interface of the refrigerator having specific colorimetric and/or temperature sensors, to evaluate in a convenience way the quality of stored meat thus reducing domestic waste: the partial least square model was based on physicochemical parameters (particularly chroma, metmyoglobin, and thiobarbituric acid reactive substances), while the square root model was based on the time-temperature conditions during storage.


Assuntos
Bactérias/isolamento & purificação , Gorduras/análise , Carne/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bovinos , Contagem de Colônia Microbiana , Cor , Microbiologia de Alimentos , Armazenamento de Alimentos , Refrigeração , Temperatura , Substâncias Reativas com Ácido Tiobarbitúrico/análise
18.
Waste Manag ; 103: 399-406, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31945709

RESUMO

Several of the waste materials that have a negative impact on the sewer system are produced by fats, oils and greases (FOG) discharged from commercial and domestic kitchens. These materials accumulate at different points in the sewer catchment, from kitchens to pumping stations, sewers and sewage treatment works (STWs), and comprise oily wastewater, floating agglomerates and hard deposits. Despite their detrimental effects, these waste materials have a high calorific content and are an ideal feedstock for energy recovery processes. So far, the overall volume of each type of waste and their physical-chemical properties in relation to their collection point are unknown. However, from a management point of view, knowledge on each feedstock quality and volumes is necessary to develop an economic viable solution for their collection and for energy recovery purposes. In this study, FOG wastes collected from households, food service establishments (FSEs), sewage pumping stations, sewers and STWs, were compared to sewage sludge in terms of organic contents and energy potentials. As expected, FOG recovered at source (households and FSEs) were 'cleaner' and had a higher energy content. Once mixed with wastewater the materials changed in composition and lost some of their energy per unit mass. Our results showed that around 94,730 tonnes.year-1 of these materials could be recovered from the Thames Water Utilities' catchment, one of the most populated in the UK. These materials could produce up to 222 GWh.year-1 as biogas, close to double of what is produced with sewage sludge digestion and around 19% of the company energy needs. Finally, even with over six million households in the catchment, the results showed that most of the FOG waste was produced by FSEs (over 48,000 premises) with an estimated average of 79,810 tonnes.year-1 compared to 14,920 tonnes.year-1 from private households. This is an important outcome as recovery from FSEs will be cheaper and easier if the company decides to implement a collection system for energy recovery.


Assuntos
Gorduras , Esgotos , Biocombustíveis , Hidrocarbonetos , Eliminação de Resíduos Líquidos , Águas Residuárias
19.
Proc Natl Acad Sci U S A ; 117(5): 2462-2472, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31953260

RESUMO

Preadipocytes can give rise to either white adipocytes or beige adipocytes. Owing to their distinct abilities in nutrient storage and energy expenditure, strategies that specifically promote "beiging" of adipocytes hold great promise for counterbalancing obesity and metabolic diseases. Yet, factors dictating the differentiation fate of adipocyte progenitors remain to be elucidated. We found that stearoyl-coenzyme A desaturase 1 (Scd1)-deficient mice, which resist metabolic stress, possess augmentation in beige adipocytes under basal conditions. Deletion of Scd1 in mature adipocytes expressing Fabp4 or Ucp1 did not affect thermogenesis in mice. Rather, Scd1 deficiency shifted the differentiation fate of preadipocytes from white adipogenesis to beige adipogenesis. Such effects are dependent on succinate accumulation in adipocyte progenitors, which fuels mitochondrial complex II activity. Suppression of mitochondrial complex II by Atpenin A5 or oxaloacetic acid reverted the differentiation potential of Scd1-deficient preadipocytes to white adipocytes. Furthermore, supplementation of succinate was found to increase beige adipocyte differentiation both in vitro and in vivo. Our data reveal an unappreciated role of Scd1 in determining the cell fate of adipocyte progenitors through succinate-dependent regulation of mitochondrial complex II.


Assuntos
Complexo II de Transporte de Elétrons/metabolismo , Gorduras/metabolismo , Obesidade/enzimologia , Estearoil-CoA Dessaturase/genética , Ácido Succínico/metabolismo , Adipócitos Bege/citologia , Adipócitos Bege/metabolismo , Adipogenia , Animais , Metabolismo Energético , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Estearoil-CoA Dessaturase/metabolismo , Termogênese
20.
J Craniofac Surg ; 31(1): 54-57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31425407

RESUMO

Craniomaxillofacial and plastic surgeons are often confronted with patients who present with enophthalmos caused mainly by trauma. In many patients, one-stage reconstruction repairs only the bony orbit, leaving intact the disfiguring enophthalmos. Thus, some filler is needed to restore the normal volume of the orbit. The authors describe a technique to correct such deformation safely and effectively. Data were collected from 30 enophthalmic patients (average age 36.67 ±â€Š11.66 years) who underwent retro-ocular injections of fat globules between August 2014 and July 2018. CT helped identify a safe injection site, and specific CT measurements quantified the volume of fat globules required. There was a significant difference between the preoperative and postoperative values for lateral orbital protrusion (P < .01), superior orbital protrusion (P < .01), and orbital volume (P < .01). Most patients were satisfied with the outcome. There were no significant complications. Injecting fat globules into the retro-orbital area is an effective technique for correcting enophthalmos deformity.


Assuntos
Enoftalmia/cirurgia , Adolescente , Adulto , Gorduras/administração & dosagem , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Órbita/cirurgia , Adulto Jovem
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