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1.
Mycorrhiza ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809313

RESUMO

Arbuscular mycorrhizal fungi (AMF) typically provide a wide range of nutritional benefits to their host plants, and their role in plant water uptake, although still controversial, is often cited as one of the hallmarks of this symbiosis. Less attention has been dedicated to other effects relating to water dynamics that the presence of AMF in soils may have. Evidence that AMF can affect soil hydraulic properties is only beginning to emerge. In one of our recent experiments with dwarf tomato plants, we serendipitously found that the arbuscular mycorrhizal fungus (Rhizophagus irregularis 'PH5') can slightly but significantly reduce water holding capacity (WHC) of the substrate (a sand-zeolite-soil mixture). This was further investigated in a subsequent experiment, but there we found exactly the opposite effect as mycorrhizal substrate retained more water than did the non-mycorrhizal substrate. Because the same substrate was used and other conditions were mostly comparable in the two experiments, we explain the contrasting results by different substrate compaction, most likely caused by different pot shapes. It seems that in compacted substrates, AMF may have no effect upon or even decrease the substrates' WHC. On the other hand, the AMF hyphae interweaving the pores of less compacted substrates may increase the capillary movement of water throughout such substrates and cause slightly more water to remain in the pores after the free water has drained. We believe that this phenomenon is worthy of mycorrhizologists' attention and merits further investigation as to the role of AMF in soil hydraulic properties.

2.
J Sci Food Agric ; 104(3): 1347-1356, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814156

RESUMO

BACKGROUND: The present study aimed to investigate the effects of large yellow croaker roe phospholipids (LYCRPLs) on the physical properties of surimi gels and to clarify their interaction mechanism with myofibrillar proteins (MPs) in terms of chemical forces and the spatial conformation. RESULTS: LYCRPLs could improve the gel strength, textural properties, rheological properties and water-holding capacity of surimi gels. Moreover, the interaction mechanism between LYCRPLs with MPs was revealed through intermolecular forces, Fourier transform infrared spectroscopy and ultraviolet visible absorption spectroscopy. The findings demonstrated that LYCRPLs enhanced the surface hydrophobicity and particle size of MPs, facilitating expansion and cross-linking of MPs. CONCLUSION: These results provide a theoretical basis for improving the characteristics of surimi gels and thus facilitate the application of LYCRPLs in the aquatic food industry. © 2023 Society of Chemical Industry.


Assuntos
Proteínas de Peixes , Perciformes , Animais , Proteínas de Peixes/química , Manipulação de Alimentos/métodos , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Produtos Pesqueiros/análise
3.
Br Poult Sci ; 65(3): 287-296, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466394

RESUMO

1. This study investigated the relationships of quality indices with the severity of wooden breast (WB) myopathy in chicken breast meat under refrigerated storage. The physicochemical properties, water-holding capacity (WHC), microbial quality and fatty acid profiles of normal chicken breast meat samples (NOR samples, n = 63), moderate WB (MWB, n = 63) myopathy and severe WB (SWB, n = 63) myopathy (MWB and SWB samples, respectively) were evaluated immediately after sampling and after 4 and 8 d of refrigerated storage at 4°C.2. Total collagen, fat, saturated and monounsaturated fatty acid contents, redness and pH of the SWB and MWB samples were higher than the NOR samples. The SWB samples that were stored for 8 d had poor WHC, total viable counts (TVC) of higher than 7.0log colony-forming units, total volatile basic nitrogen (TVB-N) content of greater than 15 mg/100 g and a thiobarbituric acid - reactive substance level of higher than 1 mg/kg malondialdehyde.3. No significant difference was observed in the TVB-N content and TVC of the MWB and NOR samples during storage. Polyunsaturated fatty acid content was lower in the SWB and MWB samples than in the NOR samples. The SWB samples were tougher than the MWB and NOR samples after 8 d of refrigeration.4. In conclusion, the quality of chicken breast meat with SWB myopathy degraded considerably over time; thus, such meat should not be subjected to extended refrigeration for storage.


Assuntos
Galinhas , Armazenamento de Alimentos , Carne , Doenças Musculares , Músculos Peitorais , Doenças das Aves Domésticas , Refrigeração , Animais , Carne/análise , Doenças Musculares/veterinária , Doenças Musculares/patologia , Músculos Peitorais/química , Músculos Peitorais/patologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/patologia , Ácidos Graxos/análise
4.
Plant Foods Hum Nutr ; 79(1): 137-142, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38206480

RESUMO

The present investigation finds that Chondracanthus chamissoi seaweed abounding in Peruvian coasts is characterized by its nutritional composition, total polyphenols, antioxidant capacity, and functional properties such as water-holding capacity (WHC), oil-holding capacity (OHC), and swelling capacity (SC). Boiling and steaming were applied before dehydration to evaluate the effect of these thermal treatments, keeping a control sample. The results indicated that the control dried seaweed sample presented 20.2 ± 0.16 g/100 g dw of proteins, 20.0 ± 0.61 g/100 g dw of ash, and 56.6 ± 0.08 g/100 g dw of total dietary fiber. In addition, the control sample presented 1.6 ± 0.07 mg GAE/g of total polyphenol content and 2.4 ± 0.30 mM Trolox mg/g of antioxidant capacity. In boiling samples, the apparent nutrient retention factors for proteins, fat, and dietary fiber are 96, 47 and 74%, respectively. In the steaming sample, the values were 102, 29, and 92%. The boiling before dehydration causes a significant decrease (p < 0.05) in total polyphenols and increases carbohydrates. Steaming before dehydration, a significant (p < 0.05) increase occurs in carbohydrates without significantly altering the concentration of total polyphenols. Regarding the functional properties, C. chamissoi presents 17.6 ± 0.15 g/g of WHC, 2.4 ± 0.78 g/g of OHC, and 9.8 ± 0.75 mL/g of SC. Boiling produces an increase in WHC and OHC; steaming does not affect the properties of the control sample.C. chamissoi seaweed collected from the coasts of Perú is an excellent alternative for use as food and ingredients in processed foods for human consumption.


Assuntos
Antioxidantes , Alga Marinha , Humanos , Antioxidantes/análise , Alga Marinha/química , Peru , Desidratação , Polifenóis/análise , Verduras , Carboidratos , Fibras na Dieta/análise
5.
BMC Plant Biol ; 23(1): 382, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550615

RESUMO

BACKGROUND: Currently, using unconventional water sources in agriculture has become necessary to face overpopulation worldwide. Therefore, a pot experiment was carried out to evaluate the effects of irrigation with saline water in the presence of co-applied wood chips biochar (WCB) with chemical fertilizers on physicochemical properties and nutrient availability as well as growth parameters, and yield of red radish (Raphanus sativus L.) grown in the saline sandy soil. METHODS: The WCB was added to the saline sandy soil at levels of 0 (control), 2.5, and 5% w/w. Then, this soil was cultivated by red radish plants and irrigated with saline water (5 dS m- 1). This experiment was performed in a randomized complete block design with three replicates. RESULTS: Compared with the control treatment, WCB treatments increased significantly soil water holding capacity by 34.8% and 73.2% for levels of 2.5 and 5%, respectively. Soil pH decreased significantly in all WCB treatments. The relative increase in the total available nitrogen over the control was 30.1 and 103.5% for 2.5 and 5% wood chips biochar, respectively. Compared to the control, applying WCB at 2.5% led to an increase in the fresh root weight of red radish plants by 142.7%, while 5% caused a decrease in the fresh root weight of red radish plants by 29.4%. CONCLUSION: Recently, WCB represents an interesting approach to the rehabilitation of saline soils and the management of using saline water sources. It is recommended that combined application of WCB at a level of 2.5% with chemical fertilizers in order to improve red radish growth and nutrient retention in the saline sandy soil which preserves the ecosystem as well as increases productivity leading to the reduction of costs.


Assuntos
Raphanus , Solo , Carvão Vegetal , Ecossistema , Fertilizantes , Águas Salinas , Areia , Solo/química , Madeira
6.
Environ Sci Technol ; 57(13): 5296-5304, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36951544

RESUMO

Agricultural soils are a major reservoir of microplastics, and concerns have arisen about the impacts of microplastics on soil properties and functioning. Here, we measured the physical properties of a silt loam in response to the incorporation of polyester fibers and polypropylene granules over a wide range of concentrations. We further elucidated the underlying mechanisms by determining the role of microplastic shape and the baseline effects from the amendment of soil particles. The incorporation of microplastics into soil tended to increase contact angle and saturated hydraulic conductivity and decrease bulk density and water holding capacity, but not affect aggregate stability. Polyester fibers affected soil physical properties more profoundly than polypropylene granules, due to the vastly different shape of fibers from that of soil particles. However, changes in soil properties were gradual, and significant changes did not occur until a high concentration of microplastics was reached (i.e., 0.5% w/w for polyester fibers and 2% w/w for polypropylene granules). Currently, microplastic concentrations in soils not heavily polluted with plastics are far below these concentrations, and results from this study suggest that microplastics at environmentally relevant concentrations have no significant effects on soil physical properties.


Assuntos
Microplásticos , Solo , Plásticos , Polipropilenos , Poliésteres
7.
J Environ Manage ; 345: 118847, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37673010

RESUMO

Poor cementation between soil particles is a fundamental cause of soil erosion and desertification. In recent decades, many polymers have been used to cement soil particles and improve the physical and chemical properties of soils. The contributions of polymers with different structures and functional groups to soil improvement vary considerably. In this study, a mixture comprising polyacrylamide (PAM), sodium polyacrylate (PAAS), hydroxypropyl methylcellulose (HPMC), and polyvinyl alcohol (PVA) was investigated to meet the requirements of soil water retention, erosion resistance, and plant growth. The results showed that the time required for the modified soil to reach drought conditions was extended by 4-7 days. The PAM/HPMC, PAM/PVA and PAM/PAAS experimental groups reduced the erosion rate by 99.57%, 98.3% and 96.38%, respectively, compared to that of the control group. The belowground plant biomass was significantly increased by PAM/HPMC, PAM/PAAS, and PAM/PVA, with increases of 115.92%, 145.23%, and 205.67%, respectively. HPMC contributed more to the soil erosion resistance and water-holding capacity, PAAS improved the soil porosity substantially, and PVA significantly increased the plant biomass. The rigid structures of the polymer chains enhanced the structural stability of the soil, and the hydrophilic functional groups increased the hydrophilicity of the amended soil. This study indicates different polymers that may be used to improve soil properties.


Assuntos
Areia , Solo , Polímeros , Álcool de Polivinil , Erosão do Solo
8.
J Sci Food Agric ; 103(1): 308-316, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35864589

RESUMO

BACKGROUND: Frozen tilapia fillet has become a leading aquatic product. High drip loss, dry and fibrous mouthfeel, and an unappealing appearance are its main problems. It was hypothesized that light salting could improve the quality, and that the preparation conditions would affect the storage stability of frozen tilapia fillets. RESULTS: The quality changes of lightly salted tilapia fillets were evaluated during frozen storage, and the underlying mechanisms were studied from the physicochemicaland microstructural perspectives. Though the salt content was 1.5% in all samples,the amount of ice crystals in frozen tissues decreased with the descending water content and freezing point (P < 0.05). No intracellular voids were observed in the samples prepared under proper salting conditions, and the myofibers were plump and smooth after freezing-thawing, which contributed to the high water-holding capacity of lightly salted fillets. After 28 days,the water-binding capacity of the salted groups was 14.69%-18.62% higher than that of their unsalted counterparts (P < 0.05). The reduced protein solubility in the salted fillets was likely to have occurred because the solubilized and unfolded proteins interacted more easily during frozen storage. The oxidation degree of myofibrillar proteins was also affected by salting condition, and the fillets with less oxidized sulfhydryl groups maintained high springiness after 28 days of frozen storage. CONCLUSION: The salting condition of 9% NaCl solution for 1 h was recommended for the preparation of lightly salted fillets from freshwater fish, taking into account quality, processing efficiency, and storage stability. The enhanced water-holding capacity and texture of lightly salted tilapia fillets were attributed to modified physicochemical and microstructural properties. These results could provide a scientific basis for the processing and storage of high-quality, frozen, lightly salted fillets from freshwater fish. © 2022 Society of Chemical Industry.


Assuntos
Ciclídeos , Tilápia , Animais , Cloreto de Sódio/química , Congelamento , Água
9.
J Sci Food Agric ; 103(2): 514-523, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36468614

RESUMO

BACKGROUND: Adenosine monophosphate-activated protein kinase (AMPK) is instrumental in the initiation of early postmortem glycolysis and the advent of pale, soft, and exudative (PSE) meat when cellular energy is altered. However, conflicting studies show that AMPK activation without corresponding energy level changes in PSE meat challenges this long-held notion. Here, we examined the effects of reactive oxygen species (ROS)-mediated oxidative stress on AMPK activation in the context of glycolysis, protein solubility, and water-holding capacity (WHC) in the postmortem yak longissimus dorsi (LD) muscle. Further, we explored the mechanisms underlying these effects. RESULTS: Hydrogen peroxide (H2 O2 ) significantly augmented the degree of oxidative stress, increasing the production of ROS and malondialdehyde excessive production and reducing the activity of the anti-oxidants superoxide dismutase and glutathione peroxidase. In turn, oxidative stress dramatically promoted AMPK activation and glycolysis by increasing glycogen depletion and promoting hexokinase and phosphofructokinase activity. Subsequently, lactic acid accumulation increased, leading to a rapid decline in pH, which aggravated protein solubility degree and centrifugal loss in the early postmortem yak LD muscle. Importantly, these changes caused by oxidative stress were eliminated by the AMPK inhibitor. Mechanistically, oxidative stress elevated calcium ion (Ca2+ ) levels, which mobilized calcium/calmodulin-dependent protein kinase ß (CaMKKß) and AMPK. Rescue experiments confirmed that the increases were attenuated using Ca2+ and CaMKKß chelators, respectively. CONCLUSION: These results indicated that oxidative stress caused by ROS hastened early-stage postmortem glycolysis and reduced the WHC of yak meat. These effects were likely mediated by the alternative and energy-independent CaMKKß/AMPK signaling pathway. © 2022 Society of Chemical Industry.


Assuntos
Proteínas Quinases Ativadas por AMP , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina , Bovinos , Animais , Espécies Reativas de Oxigênio , Proteínas Quinases Ativadas por AMP/genética , Cálcio , Estresse Oxidativo , Glicólise , Transdução de Sinais
10.
Br Poult Sci ; 64(3): 364-369, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36622118

RESUMO

1. In order to meet market demand for poultry, producers strive to ensure processing plants are more efficient. One of the ways of achieving better productivity is to remove meat from the carcase straight after slaughter. To diminish the negative consequences of this procedure, various processing techniques can be used, with brining being one of the most popular of these techniques.2. The aim of this study was to evaluate the physicochemical and sensory properties of chicken breast meat subjected to the procedure of early deboning and brine injection prior to chilling, as well as to verify the influence of brine on characteristics of the meat.3. To evaluate meat characteristics and verify the influence of brine injection on its quality, pH and water-holding capacity (WHC) were determined. Desirability of odour, taste, juiciness and tenderness to the consumer was evaluated. The intensity of odour and taste was assessed by a team of selected assessors in order to verify their influence on the consumer desirability of these features.4. The results showed that pH was lower, whereas WHC was more favourable in the case of brined meat. Moreover, sensory evaluations indicated that the desirability of taste and juiciness was significantly higher in the brined samples.5. Early deboning and brine injection prior to chilling of chicken breast meat had a positive influence on the sensory variables of the ready-to-eat product, thus contributing to its higher consumer acceptability.


Assuntos
Galinhas , Manipulação de Alimentos , Animais , Manipulação de Alimentos/métodos , Sais , Carne/análise , Água
11.
Environ Monit Assess ; 195(8): 932, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432491

RESUMO

Afforestation can improve soil erosion in the ecologically fragile areas of the Loess Plateau; however, the amount of water and phosphorus fertilizer that can promote vegetation survival is unclear, which hinders the improvement of the local ecological environment and the waste of water and fertilizer. In this study, based on field surveys, water and fertilizer control tests on Robinia pseudoacacia L. seedlings in experimental fields, and fitting CO2 response curves to R. pseudoacacia seedlings using a Li-6400 portable photosynthesizer, we measured their leaf nutrient contents and calculated resource use efficiency. The results showed that (1) under the same moisture gradient, except for photosynthetic phosphorus utilization efficiency (PPUE), light use efficiency (LUE), water use efficiency (WUE), carbon utilization efficiency (CUE), and photosynthetic nitrogen use efficiency (PNUE) all increased with increasing phosphorus fertilizer application. Under the same phosphorus fertilizer gradient, WUE increased with decreasing water application, and LUE, CUE, PNUE, and PPUE all reached the maximum at 55-60% of field water holding capacity. (2) Net photosynthetic rate (Pn) of R. pseudoacacia seedlings increased with increasing intercellular carbon dioxide concentration (Ci), and as Ci continued to increase, the increase in Pn became slower, but no maximal electron transport rate (TPU) occurred. Under the same CO2 concentration, Pn reached a maximum at 55-60% of field water holding capacity and phosphorus fertilizer at 30 gPm-2·a-1. (3) Leaf maximum carboxylation rate (Vcmax), maximum electron transport rate (Jmax), daily respiration (Rd), stomatal conductance (Gs), and mesophyll conductance (Gm) reached their maximum at 30 gPm-2·a-1 of phosphorus fertilizer. Vcmax, Jmax, and Rd reached their maximum at 55-60% of field water holding capacity; Gs and Gm reached their maximum at 75-80% of field water holding capacity. (4) The higher the soil phosphorus content, the lower the biochemical (lb), stomatal (ls), and mesophyll (lm). With the increase of soil moisture, lb and ls are higher, and lm is lower. (5) Structural equation modeling showed that water-phosphorus coupling had a less direct effect on Rd and a more direct impact on Gs and Gm. Relative photosynthetic limitation directly affected the photosynthetic rate, indicating that water and phosphorus affected the photosynthetic rate through relative plant limitation. It was concluded that the resource use efficiency and photosynthetic capacity reached the maximum when 55-60% of field water holding capacity was maintained, and phosphorus fertilization was at 30 gP m-2·a-1. Therefore, maintaining suitable soil moisture and phosphorus fertilizer levels in the semi-arid zone of the Loess Plateau can improve the photosynthetic capacity of R. pseudoacacia seedlings.


Assuntos
Robinia , Solo , Plântula , Dióxido de Carbono , Fertilizantes , Monitoramento Ambiental , China , Nitrogênio , Fósforo
12.
J Food Sci Technol ; 60(6): 1656-1665, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37187980

RESUMO

Yogurt, produced by the lactic fermentation of milk base, is an important dairy product worldwide. One of the essential sensory properties of yogurt is the texture, and some textural defects such as weak gel firmness and syneresis likely occur in various types of yogurts, affecting consumer acceptance. In this regard, various strategies such as enrichment of milk-based with different additives and ingredients such as protein-based components (skimmed milk powder (SMP), whey protein-based powders (WP), casein-based powders (CP), and suitable stabilizers, as well as modification of processing conditions (homogenization, fermentation, and cooling), can be applied in order to reduce syneresis. The most effective proteins and stabilizers in syneresis reduction are CP and gelatin, respectively. Furthermore, yogurt's water holding capacity and syneresis can be affected by the type of starter cultures, the protolithic activity, production of extracellular polysaccharides, and inoculation rate. Moreover, optimizing the heat treatment process (85 °C/30 min and 95 °C/5 min), homogenization (single or dual-stage), incubation temperature (around 40 °C), and two-step cooling process can decrease yogurt syneresis. This review is aimed to investigate the effect of fortification of the milk base with various additives and optimization of process conditions on improving texture and preventing syneresis in yogurt.

13.
J Dairy Res ; : 1-7, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35388774

RESUMO

We investigated the use of near-infrared spectroscopy (NIR) for measuring water-holding capacity (WHC) in fermented milk. Increased WHC ensures improved texture and decreased syneresis in fermented dairy products and also improves cheese yield. NIR combined with partial least-squares-discriminant analysis (PLS-DA) was found to be a promising rapid and non-invasive method with no pretreatment of the samples for prediction of WHC in fermented milk samples. Analysis of the chemical bonds in the region 10 700-4500 cm-1 (935-2200 nm) of the electromagnetic spectrum was able to distinguish between samples with high vs. low WHC. This technique was successfully used to screen different strains of lactic acid bacteria for their ability to provide fermented milk with increased WHC, which is of great importance for use in various dairy products.

14.
J Environ Manage ; 324: 116247, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174471

RESUMO

Nowadays, wastewater treatment plants (WWTPs) are transforming into water resource recovery facilities (WRRFs) where the resource recovery from waste streams is pivotal. Aerobic granular sludge (AGS) is a novel technology applied for wastewater treatment. Extracellular polymeric substances (EPS) secreted by microorganisms promote the aggregation of bacterial cells into AGS and the structural fraction of EPS (sEPS) is responsible for the mechanical properties of AGS. sEPS can be extracted and recovered from waste AGS by physico-chemical methods and its characterization is to date of relevant concern to understand the properties in the perspective of potential applications. This study reports on: characterization of sEPS extracted and recovered from AGS; - formation and characterization of sEPS-based hydrogels. Briefly, sEPS were extracted by a thermo-alkaline process followed by an acidic precipitation. sEPS-based hydrogels were formed by a cross-linking process with a 2.5% w/w CaCl2 solution. The following key-findings can be drawn: i) hydrogels can be formed starting from 1% w/w sEPS on, by diffusion of Ca2+ into sEPS network; ii) the Ca/C molar ratio of hydrogels decreased with increasing concentration of sEPS from 1 to 10% w/w; iii) the thermogravimetric and spectroscopic behaviours of sEPS show that the cross-linking reaction mainly involves the polysaccharidic fraction of biopolymers; iv) water-holding capacity up to 99 gH2O/gsEPS was registered for 1% w/w sEPS-based hydrogels, suggesting applications in several industrial sectors (i.e. chemical, paper, textile, agronomic, etc.); v) rheological results highlighted a solid-like behaviour (G'≫G") of sEPS-based hydrogels. The power-law fitting of G' vs. sEPS concentration suggests that the expansion of the sEPS network during cross-linking occurs through a percolative mechanism involving the initial formation of sEPS oligomers clusters followed by their interconnection towards the formation of 3D network. These findings provide additional information about the mechanisms of sEPS-based hydrogel formation and reveal the peculiar physico-chemical characteristics of sEPS which nowadays are increasingly gaining interest in the context of resource recovery.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Eliminação de Resíduos Líquidos/métodos , Hidrogéis , Biopolímeros/química , Reatores Biológicos , Águas Residuárias , Aerobiose
15.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296614

RESUMO

Fish are vulnerable to environmental pollutants such as polycyclic aromatic hydrocarbon and heavy metals. As one of the most commonly applied processing methods, the smoking of different species has been applied globally. Hence, this study aims to investigate the smoking process on the polycyclic aromatic hydrocarbon and elemental accumulation of the five different species (rainbow trout, Atlantic bonito, horse mackerel, sea bass, and Atlantic bluefin tuna) which are commonly processed and traded in the smoked fish industry. The processing yield, water holding capacity, and pH were also investigated. The results revealed that the proximal differences among fish species influence the water holding capacity, processing yield, and pH which are very important for process sustainability and the quality of the end product. The main finding was the proximal composition impact on the accumulation of both PAHs and heavy metals at different levels. While all of the tested samples were below the maximum permissible limit, some of the heavy metals, especially toxic elements, were found above the acceptable limit. Horse mackerel is determined to be the species most vulnerable to PAHs and heavy metal accumulation.


Assuntos
Poluentes Ambientais , Metais Pesados , Oncorhynchus mykiss , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Hidrocarbonetos Policíclicos Aromáticos/química , Fumaça , Metais Pesados/química , Água , Poluentes Químicos da Água/química
16.
J Sci Food Agric ; 102(13): 5618-5627, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35340026

RESUMO

BACKGROUND: Isolation of lysozyme from egg white (EW) using ion exchange resin adsorption method generates large quantities of lysozyme-free egg white (LFEW) with poor gelling property. To maximize the applications of LFEW, the effect of Lactiplantibacillus plantarum fermentation on the gel properties of LFEW was investigated in this study. RESULTS: The fermentation efficiency of LFEW with lysozyme removed was significantly improved, and the sugar removal rate (2 g kg-1 Lactiplantibacillus plantarum, 37 °C, 7 h) was more than 90%. Removal of lysozyme resulted in increased stability and surface hydrophobicity of EW. After Lactiplantibacillus plantarum fermentation, the stability of EW decreased, and the average particle size and surface hydrophobicity increased. In addition, by comparing the gel properties of EW and LFEW before and after fermentation at different pH, it was found that the hardness, elasticity, and water holding capacity (WHC) of EW gel increased significantly. The removal of lysozyme effectively improved the WHC and springiness of the EW gel and promoted the formation of a denser network structure with smaller pores. After Lactiplantibacillus plantarum fermentation treatment, LFEW gel hardness decreased, with loose and porous network structure, no browning occurred after autoclaving. CONCLUSION: This study provided the direction and theoretical basis for producing a fermented LFEW gel with pleasing texture and appearance. © 2022 Society of Chemical Industry.


Assuntos
Clara de Ovo , Lactobacillus plantarum , Clara de Ovo/química , Fermentação , Géis , Interações Hidrofóbicas e Hidrofílicas
17.
Trop Anim Health Prod ; 54(1): 47, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35018555

RESUMO

This study aimed to compare the physicochemical characteristics, fatty acid composition, and sensory attributes of the meat from three genetic groups: Nellore (Nell), ½ Nellore × ½ Angus (NeAn), and » Nellore × » Angus × ½ Senepol (NASe). Longissimus lumborum muscle from 30 slaughtered bulls with a body weight of 549 ± 32.5 kg was used. The water holding capacity was greater for the Nell and NeAn groups than for the NASe group. Meat samples from the NASe group exhibited a higher L* index than those from the NeAn group and lower a* and b* color indexes than those from the Nell group. The meat fatty acid profiles showed that the Nell group had higher concentrations of 12:0, 14:0, 18:1 t11, 14:1 c9, 16:1 c9, 18:1 c9, 18:1 c11, 18:2 c9, t11 (conjugated linoleic acid (CLA)), and 20:3 n-6 polyunsaturated fatty acid (PUFA) than the NeAn and NASe groups. The total saturated (ΣSFA), unsaturated (ΣUFA), and monounsaturated (ΣMUFA) fatty acid concentrations were higher and the ΣPUFA:ΣSFA ratio was lower in the Nell group than in the NeAn group. The Δ9-desaturase C16 activity was significantly higher in the Nell and NASe groups than in the NeAn group. The atherogenicity index (AI) tended to be lower in the crossbreeds than in the Nell breed. The NASe group presented meat with better tenderness, juiciness, and overall acceptance than the Nell and NeAn groups and was therefore the best genetic group for beef production of the tested groups.


Assuntos
Ácidos Graxos , Carne , Animais , Peso Corporal , Bovinos , Ácidos Graxos Insaturados , Masculino , Carne/análise , Músculos
18.
Planta ; 253(1): 14, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33392847

RESUMO

MAIN CONCLUSION: During desiccation, both apparent electron transport rate (ETRapp) and photosynthetic CO2 uptake peak when external water has evaporated. External water, causing suprasaturation, weakens the strong correlation between ETRapp and CO2 uptake. Lichens are poikilohydric organisms passively regulated by ambient conditions. In theory, apparent electron transport rate (ETRapp), estimated by photosystem II yield measured in light (ΦPSII), is a proxy of photosynthetic CO2 uptake. Hydration level, however, is a complicating factor, particularly during suprasaturation that strongly reduces CO2 diffusion. Here, the cephalolichen Lobaria pulmonaria and two chlorolichens Parmelia sulcata and Xanthoria aureola were excessively hydrated before photosynthetic CO2 uptake and ΦPSII using imaging fluorescence tools were simultaneously measured while drying at 200 µmol photons m-2 s-1. CO2 uptake peaked when hydration had declined to a level equivalent to their respective internal water holding capacity (WHCinternal) i.e., the water per thallus area after blotting external water. CO2 uptake and ETRapp in all species were highly correlated at hydration levels below WHCinternal, but weaker at higher hydration (chlorolichens) or absent (cephalolichen). Yet, at a specimen level for the two chlorolichens, the correlation was strong during suprasaturation. The CO2 uptake-ETRapp relationship did not differ between measured species, but may vary between other lichens because the slope depends on cortical transmittance and fraction of electrons not used for CO2 uptake. For new lichen species, calibration of ETRapp against CO2 uptake is therefore necessary. At intrathalline scales, ΦPSII during drying initially increased along thallus margins before reaching maximum values in central portions when hydration approached WHCinternal. WHCinternal represents the optimal hydration level for lichen photosynthesis. In conclusion, ETRapp is an easily measured and reliable proxy of CO2 uptake in thalli without external water but overestimates photosynthesis during suprasaturation.


Assuntos
Dióxido de Carbono , Transporte de Elétrons , Líquens , Ascomicetos/metabolismo , Dióxido de Carbono/metabolismo , Clorofila , Líquens/metabolismo , Luz , Parmeliaceae/metabolismo , Fotossíntese/fisiologia
19.
Trop Anim Health Prod ; 53(4): 415, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34312698

RESUMO

The study aimed to investigate the effects of slaughter age and gender on specific carcass and technological meat quality characteristics in Anatolian water buffaloes. The study was conducted on 55 water buffaloes using a 2 × 2 factorial design with two independent variables at two levels. Gender subgroups of male (n = 29) and female (n = 26) and slaughter age subgroups of younger than 2 years of age (n = 29) and older than 2 years of age (n = 26) were evaluated. Hot carcass and cold carcass weights were higher in old water buffaloes than young ones (P < 0.001). The skin weight of old buffaloes was also higher than young buffaloes (P < 0.01). Drip loss, expressed juice, and Warner Bratzler (WB) shear force values of longissimus dorsi (LD) muscles were not influenced by age group and gender of buffaloes. The lightness (L*) and hue (H*) values were higher in young buffaloes than old animals (P < 0.001). The meat of male buffaloes had lower redness (a*) and chroma (C*) values than that of female buffaloes. The current results indicated that female water buffalo could also be used for meat production away from negative impressions on the meat quality of female water buffalo.


Assuntos
Bison , Búfalos , Animais , Feminino , Masculino , Carne/análise
20.
J Food Sci Technol ; 58(1): 175-185, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33505062

RESUMO

The influences of spray-drying and freeze-drying processes on functional properties of ginkgo seed proteins (GSP) were systematically investigated. It was revealed that GSP dried by spray (SGSP) displays an significantly improved water holding capacity and superior emulsifying properties than the freezing-drying GSP (FGSP), whereas, the oil binding capacity is higher in FGSP. The difference in properties of SGSP and FGSP can be attributed to their different structural characteristics. Comparing with FGSP, SGSP was demonstrated having more disulfide bonds, more amorphous and less ordered structure, accounted for big differences in functional properties. With the outstanding functional characteristics, GSP could be potentially applied in oil-in-water type food system, such as milk and mayonnaise. Finally, it is important to choose the suitable drying method according to the requirements of the specific food system.

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