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1.
Food Chem ; 336: 127730, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768900

RESUMO

Phenols are responsible for the only health claim of virgin olive oil (VOO) recognized by the European Commission EU 432/2012 and the European Food Safety Authority. In this research, we studied the decrease in the phenolic content of 160 extra VOOs (EVOOs) after 12 months storage in darkness at 20 °C. Phenolic concentration was decreased 42.0 ± 24.3% after this period and this reduction strongly depended on the initial phenolic profile. Hence, EVOOs with predominance in oleacein and oleocanthal experienced a larger decrease in phenolic content than oils enriched in other phenols. Complementarily, hydroxytyrosol and oleocanthalic acid increased significantly in aged EVOOs, which allowed their discrimination from recently produced EVOOs. These changes are explained by degradation of main secoiridoids during storage due to their antioxidant properties. Hydroxytyrosol and oleocanthalic acid can be considered markers of olive oil ageing, although they can also provide information about quality or stability.


Assuntos
Armazenamento de Alimentos/métodos , Azeite de Oliva/química , Fenóis/química , Antioxidantes/química , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Iridoides/análise , Fenóis/análise , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Curva ROC , Espectrometria de Massas em Tandem , Fatores de Tempo
2.
Food Chem ; 334: 127611, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712493

RESUMO

Plant polyphenols applied as natural antioxidant ingredients, are known to bind to cysteine residues on meat proteins. The aim of this study was to examine the effect of light exposure on the formation of cysteine-phenol adduct in meat added 4-methylcatechol (4MC), a model polyphenol, during storage through quantitative LC-MS/MS-based analysis. Cysteine-4-methylcatechol adduct (Cys-4MC) formation in meat added 1500 ppm 4-MC increased significantly (by 50%) when stored under light in oxygen at 4 °C for 7 days as compared to storage in the dark. This was reflected by a significant decrease in thiol concentrations in the same sample. Gel electrophoresis showed loss in myosin heavy chain (MHC), and a resulting increase in cross-linked MHC (CL-MHC) and larger protein polymers in samples added 4MC. Protein blots stained with nitroblue tetrazolium (NBT) showed intensive protein-polyphenol binding in the meat samples added 4MC, but no major differences between storage conditions.


Assuntos
Catecóis/química , Armazenamento de Alimentos/métodos , Proteínas de Carne/química , Carne , Oxigênio/química , Antioxidantes/química , Cromatografia Líquida , Cisteína/química , Eletroforese em Gel de Poliacrilamida , Luz , Carne/análise , Proteínas de Carne/metabolismo , Cadeias Pesadas de Miosina/química , Compostos de Sulfidrila/química , Espectrometria de Massas em Tandem
3.
Food Chem ; 336: 127590, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763742

RESUMO

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.


Assuntos
Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Óleos Voláteis/farmacologia , Penicillium/efeitos dos fármacos , Thymus (Planta)/metabolismo , Antioxidantes/química , Citrus/química , Citrus/metabolismo , Citrus/microbiologia , Temperatura Baixa , Sucos de Frutas e Vegetais/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Óleos Voláteis/análise , Penicillium/fisiologia
4.
Food Chem ; 336: 127618, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771896

RESUMO

Litchi fruit were exposed to 0.7 PPM hydrogen water (HW) before storage at 25 ± 1 â„ƒ. HW treatment delayed the pericarp browning and maintained the total soluble solids (TSS) of litchi fruit. Then, a total of 25 antioxidant system-related characters were determined to evaluate the effects of HW on antioxidant system during pericarp browning. Compared with control pericarp, the pericarp of HW-treated litchi fruit exhibited higher levels of superoxide radical (O2-·) scavenging activity, glutathione (GSH), monodehydroascorbate reductase (MDHAR), polyphenol oxidase (PPO) and total flavonoids during whole storage, higher levels of hydrogen peroxide (H2O2), catalase (CAT), glutathione disulfide (GSSG), ascorbate oxidase (AAO) and total phenols only on day 1, and higher levels of ascorbate peroxidase (APX), total anthocyanin, glutathione reductase (GR) and glutathione peroxidases (GPX) at later stage of storage. Those HW-induced antioxidant system-related characters might directly or indirectly enhanced the antioxidant capacity and delayed the pericarp browning of litchi.


Assuntos
Antioxidantes/química , Armazenamento de Alimentos/métodos , Hidrogênio/química , Litchi/metabolismo , Catalase/metabolismo , Análise Discriminante , Flavonoides/química , Flavonoides/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Glutationa Redutase/metabolismo , Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , Análise dos Mínimos Quadrados , Litchi/química , Litchi/efeitos dos fármacos
5.
Food Chem ; 334: 127487, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688178

RESUMO

Biodegradable films poly(butylene adipate-co-butylene terephthalate) (PBAT)/poly(lactic acid) (PLA) incorporated with nano-polyhedral oligomeric silsesquioxane (POSS(epoxy)8) as a reactive compatibilizer were developed by melt processing. Structural, morphological, mechanical, and gas permeability properties of the films were determined. 1H NMR and GPC demonstrated that the POSS(epoxy)8 was chemically bound at the PBAT/PLA boundary phase via an epoxide ring opening reaction. SEM micrographs of impact fracture surfaces demonstrated the POSS(epoxy)8 improved interfacial adhesion between PBAT and PLA matrix. The mechanical properties of the PBAT/PLA films containing POSS(epoxy)8 were enhanced relative to pristine PBAT/PLA films. The water vapor, CO2 and O2 permeability of the PBAT/PLA films were improved by POSS(epoxy)8 addition. PBAT/PLA films containing POSS(epoxy)8 were shown to be superior to pristine PBAT/PLA films and polyethylene films in food storage tests. Results suggest that POSS(epoxy)8 addition during PBAT/PLA film production offers a simple strategy for the production of high performance biodegradable plastic packaging films.


Assuntos
Plásticos Biodegradáveis/química , Embalagem de Alimentos/métodos , Nanocompostos/química , Poliésteres/química , Dióxido de Carbono/química , Armazenamento de Alimentos/métodos , Oxigênio/química , Permeabilidade , Resistência à Tração
6.
Food Chem ; 334: 127547, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693334

RESUMO

Plastic food packages usually contain additives which may migrate from the package into the food and then be ingested by the consumer, representing a risk for their health. In this study, targeted and untargeted analysis by gas chromatography-mass spectrometry (GC-MS) is proposed to monitor any contaminants of this type in honey. The application of dispersive liquid-liquid microextraction (DLLME) as a preconcentration technique allowed very low detection limits to be reached for all the substances. Fifteen target compounds, including styrene, phthalates, fatty acids, alkylphenols and bisphenol A, were quantified. Untargeted analyses were also carried out, allowing other migrants in the honey samples to be identified, such as two phthalates, four acids, three esters, one aldehyde, one hydrocarbon and two alkyl phenol compounds. The proposed method was seen to be a useful approach for the quantification and identification of potential migrants from plastics in challenging samples such as honey.


Assuntos
Armazenamento de Alimentos/métodos , Mel/análise , Plásticos/química , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Microextração em Fase Líquida , Fenóis/análise , Fenóis/isolamento & purificação , Ácidos Ftálicos/análise , Ácidos Ftálicos/isolamento & purificação , Migrantes
7.
Food Chem ; 334: 127548, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712487

RESUMO

The study examined the influence of the process of extrusion on the physical properties and nutritional composition of black chokeberry pomaces. It has been determined that the extrusion process resulted in a reduction of the content of anthocyanins and fibre, but an increase of the contribution of simple sugars. In order to assess the phase transitions occurring in the products, a state diagram was utilized, which was constructed using the freezing and vitrification curve and values characterizing the conditions of maximum cryoconcentration. The determined values of critical water activity (based on water activity concepts) indicate that pomaces and extrudates retain crispiness in storage under moderate environmental relative humidity conditions. However, in the case of the glass transition concept, the determined values of water activity indicate that products stored in room temperature must be protected against the influence of humidity.


Assuntos
Armazenamento de Alimentos/métodos , Photinia/química , Adsorção , Umidade , Transição de Fase , Photinia/metabolismo , Temperatura , Temperatura de Transição , Água/química
8.
PLoS One ; 15(9): e0238237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925932

RESUMO

The objective of this paper is to assess foodstuff storage throughout Recent Prehistory (5600-50 BCE) from the standpoint of the three different types (household, surplus and supra-household) identified in the northeast of the Iberian Peninsula. The volumetric data of the underground silos serves as a proxy to evaluate the link between them and the agricultural systems and technological changes. The study also assesses the ability, and specifically, the will of the ancient communities of the northeastern Iberia to generate domestic and extra-domestic surpluses.


Assuntos
Agricultura/métodos , Características da Família/história , Armazenamento de Alimentos/história , Armazenamento de Alimentos/métodos , Agricultura/estatística & dados numéricos , Armazenamento de Alimentos/normas , História Antiga , História Medieval , Humanos , Região do Mediterrâneo
9.
PLoS One ; 15(9): e0235522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946481

RESUMO

Light conditions in retail stores may contribute to potato greening. In this study, we aimed to develop a potato tuber greening risk rating model for retail stores based on light quality and intensity parameters. This was achieved by firstly exposing three potato varieties (Nicola, Maranca and Kennebec) to seven specific light wavelengths (370, 420, 450, 530, 630, 660 and 735 nm) to determine the tuber greening propensity. Detailed light quality and intensity measurements from 25 retail stores were then combined with the greening propensity data to develop a tuber greening risk rating model. Our study showed that maximum greening occurred under blue light (450 nm), while 53%, 65% and 75% less occurred under green (530 nm), red (660 nm) and orange (630 nm) light, respectively. Greening risk, which varied between stores, was found to be related to light intensity level, and partially explained potato stock loss in stores. Our results from this study suggested that other in-store management practices, including lighting duration, average potato turnover, and light protection during non-retail periods, likely influence tuber greening risk.


Assuntos
Luz/efeitos adversos , Iluminação/efeitos adversos , Tubérculos/efeitos da radiação , Solanum tuberosum/efeitos da radiação , Verduras/efeitos da radiação , Comércio , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Iluminação/instrumentação , Iluminação/métodos , Tubérculos/metabolismo , Medição de Risco/métodos , Fatores de Risco , Solanum tuberosum/economia , Solanum tuberosum/metabolismo , Fatores de Tempo , Verduras/economia , Verduras/metabolismo
10.
Food Chem ; 332: 127375, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622189

RESUMO

Biopolymer films based on chitosan/potato protein/linseed oil/ZnO NPs were developed to maintain the storage quality of raw meat. Results indicated that the incorporation of ZnO NPs could effectively improve the transparency and tensile strength of the films, while addition of linseed oil could make the composite film maintain good elastic property. Films blended with chitosan/potato protein/linseed oil/ZnO NPs (Fcpzl) exhibited an excellent moisture barrier capability. SEM showed that ZnO NPs could harmoniously exist in various polymers matrix. FTIR analysis demonstrated that different components were bound together by intramolecular and intermolecular interactions, among which hydrogen bonds were the main force. Raw meat samples were wrapped with different films to evaluate the preservative effect during 4 °C storage. Results indicated that Fcpzl possessed best protective effect of raw meat with excellent acceptable sensory properties during 7 days storage, which could reduce the speed of increasing pH and total bacterial counts.


Assuntos
Quitosana/química , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Óleo de Semente do Linho/química , Carne , Proteínas de Plantas/química , Óxido de Zinco/química , Qualidade dos Alimentos , Carne/microbiologia , Solanum tuberosum/química , Resistência à Tração
11.
Food Chem ; 332: 127416, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619946

RESUMO

Water bamboo shoots quickly deteriorate after harvest as a result of rapid lignification and softening. Nitric oxide (NO) has been used to extend the postharvest life of several other vegetables. Here, we examined the effect of NO on the storage of water bamboo shoots at 4℃ for 28 days. Without NO, fresh weight and firmness decreased quickly, while the cellulose and lignin contents increased sharply during storage. NO treatment delayed softening by maintaining the integrity of the cell wall and inhibiting the degradation of protopectin and the expressions of pectin methylesterase and polygalacturonase. NO treatment also delayed cellulose synthesis by increasing cellulase activity. NO treatment decreased the synthesis of lignin by inhibiting the activities of phenylalanine ammonia-lyase, cinnamyl alcohol dehydrogenase, laccase and peroxidase. These results indicate that NO treatment is effective at suppressing the softening and lignification of water bamboo shoots during postharvest storage.


Assuntos
Armazenamento de Alimentos/métodos , Óxido Nítrico/farmacologia , Poaceae/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/ultraestrutura , Celulase/metabolismo , Celulose/metabolismo , Temperatura Baixa , Lignina/metabolismo , Microscopia Eletrônica de Varredura , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Poaceae/metabolismo , Poligalacturonase/metabolismo
12.
J Oleo Sci ; 69(8): 809-814, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32641604

RESUMO

In this work, the evolution of virgin olive oil from 4 olive varieties when stored at 5°C, 10°C and 20°C for a period of up to 3 years was studied. Free acidity increased progressively for the 4 varieties, staying below the limit for extra virgin olive oil, even at the highest temperature. The peroxide value also increased, reaching its maximum after about 28 months of storage, when some samples stored at 20°C exceeded the limit for extra virgin olive oil. The maximum values for K270 and K232 were reached at the end of the storage period, also exceeding the limit for extra virgin olive oil in the case of some varieties stored at 20°C. Oxidative stability decreased by 38%-50% depending on the storage temperature and the variety. Most of the color indexes increased in value because of the degradation of the oil pigments.


Assuntos
Armazenamento de Alimentos/métodos , Azeite de Oliva/química , Temperatura , Cor , Azeite de Oliva/análise , Oxirredução , Peróxidos/análise , Pigmentos Biológicos/química , Fatores de Tempo
13.
Anim Sci J ; 91(1): e13423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32648277

RESUMO

Meat tenderness is considered as the most important criterion for meat quality by consumers and can be improved by the actions of endogenous proteases, mainly calpains, during postmortem storage at 0-5°C. The purpose of this study, therefore, was to examine the postmortem calpain activation and proteolysis in breast (BM) and leg and thigh (LM) muscles of White Roman goose. BM and LM were taken from goose carcasses (n = 15) at 0 (10-15 min postmortem), 1, 3, and 7 days of storage at 5°C. The decrease in postmortem pH, calpain-1 and -11 activities, and contents of the calpain-1 80 kDa subunit and desmin was more rapid (p < .05) in BM than in LM. Our results show that postmortem proteolysis was more extensive in BM than in LM of White Roman goose, not only because the difference in fiber type composition between two muscles, but because the rate and extent of calpain activation were greater in BM as well. These results may provide useful information to optimize meat processing for different muscles in goose industry.


Assuntos
Calpaína/metabolismo , Qualidade dos Alimentos , Gansos , Carne , Músculo Esquelético/metabolismo , Proteólise , Animais , Calpaína/análise , Temperatura Baixa , Manipulação de Alimentos , Armazenamento de Alimentos/métodos , Concentração de Íons de Hidrogênio , Carne/análise , Mudanças Depois da Morte , Fatores de Tempo
14.
Food Chem ; 330: 127256, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540529

RESUMO

The objective of the present study was to investigate the effectiveness of different 1-MCP treatment patterns on alleviating chilling injury (CI) of postharvest nectarine stored at 0 ± 1 °C. Nectarine fruits were subjected to the following treatments: Single-High dose 1-MCP treatment (S-H): 1 µL L-1 application before storage; Multi-low dose 1-MCP treatment: (M-L) Five 0.25 µL L-1 applications after 0, 5, 10, 15, and 20 d of storage; Multi-high dose 1-MCP treatment (M-H): Five 1 µL L-1 applications after 0, 5, 10, 15 and 20 d of storage. The results showed that although all 1-MCP treatments alleviated CI, M-H 1-MCP treatment is the most effective pattern in alleviating CI of nectarine fruit in S-H, M-L, and M-H 1-MCP treatments. Moreover, this study indicated that the reduction of CI in nectarine by 1-MCP application was related to its regulations of ROS and energy metabolism.


Assuntos
Ciclopropanos/farmacologia , Prunus/efeitos dos fármacos , Temperatura Baixa , Metabolismo Energético , Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Frutas/metabolismo , Néctar de Plantas , Prunus/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Int J Food Microbiol ; 328: 108669, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32497922

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for several difficult-to-treat infections and staphylococcal food poisoning (SFP). This study was conducted to investigate the prevalence and enterotoxigenicity of MRSA in broiler chicken meat and giblets. A total of 5.5% (8/144) of the examined samples were contaminated with mecA positive/mecC negative MRSA, with staphylococcal counts of approximately 102 colony forming units (CFU)/g in breast, leg and gizzard samples and approximately 3.3 × 103 CFU/g in frozen liver samples. Most MRSA isolates (75%, 6/8) harboured the staphylococcal enterotoxin B (seb) gene. Reverse transcription-PCR (RT-PCR) showed that MRSA isolates initiated SEB production in experimentally contaminated chicken livers within 24 h of storage at temperatures over 8 °C. SEB was maximally produced at 24 °C when the MRSA counts reached 7.3 × 103 ± 1.2 × 103 CFU/g sample homogenate. The current study concludes that the main broiler chicken MRSA isolates in Egypt harbour the seb gene. To mitigate possible SEB production, especially in broiler chicken livers, a maximum "out of refrigeration" time limit should be implemented for cold chain poultry products.


Assuntos
Enterotoxinas/genética , Armazenamento de Alimentos/métodos , Fígado/microbiologia , Carne/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Produtos Avícolas/microbiologia , Animais , Galinhas/microbiologia , Egito/epidemiologia , Microbiologia de Alimentos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/metabolismo , Refrigeração , Infecções Estafilocócicas/epidemiologia
16.
PLoS One ; 15(6): e0234781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559209

RESUMO

In meat processing, antimicrobial treatment applied during slaughter and deboning may not control pathogens and spoilage organisms during subsequent transportation and storage. "Functional Ice" (FICE), an innovation over traditional ice, was investigated for its effects on food safety, shelf life, and quality of raw poultry thigh meat during refrigerated storage. FICE was prepared by freezing aqueous solutions of sodium tripolyphosphate (STPP) (2.5% and 5% w/v) and sodium lactate-sodium diacetate (SL-SD) (1% and 2.5% v/v). Potable water was used to prepare ice for the control treatment. Thigh meat inoculated with Salmonella Typhimurium (108 CFU/sample) was placed in FICE treatments, stored at 4 °C and sampled at 0, 12, 24, 36 and 48 h (n = 375). Weight pick-up was recorded for the uninoculated thighs. Additionally, shelf life and quality were evaluated for 8 days on tray-packed thighs that were stored in FICE treatments for 48 h (STPP 5%, and SL-SD 2.5%). Differences among treatments were determined using ANOVA with LSMeans (p ≤ 0.05). Results indicated that inoculated thighs stored in individual STPP 5%, and SL-SD 2.5% treatments lead to a significant reduction in Salmonella Typhimurium compared to the control (p ≤ 0.05) after 48 h of storage. FICE treated thighs showed higher yields, lower cook loss, and an extended shelf life of 1-2 days, without any color changes. FICE has the potential to improve food safety and shelf life while improving the yields and quality during storage and transportation of raw poultry meat.


Assuntos
Inocuidade dos Alimentos , Armazenamento de Alimentos/métodos , Carne/microbiologia , Acetatos/química , Acetatos/farmacologia , Animais , Temperatura Baixa , Polifosfatos/química , Polifosfatos/farmacologia , Aves Domésticas , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Lactato de Sódio/química , Lactato de Sódio/farmacologia
17.
Food Chem ; 328: 127040, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32512467

RESUMO

Wine ageing in barrels is conditioned, among other factors, by the amount of oxygen received during this process, which thus impacts its final properties. The aim of this study was to evaluate the effect of oxygen on wine colour during ageing in barrels and bottles during different times. The use of barrels with different and known rates of oxygenation allows the effect of different oxygenation conditions throughout the process in barrels and its later evolution in bottles. A simulation process of ageing in bottles was used to study the impact of bottling in wines after differing ageing periods in barrels. The study of winés oxygen consumption capacity has been tied to colour modifications during ageing in barrels and bottles. Wines aged in barrels with a high oxygenation rate showed greater avidity to consume oxygen taking less time to consume that available, which is reflected in a greater increase in colour intensity.


Assuntos
Armazenamento de Alimentos/métodos , Oxigênio/química , Vinho/análise , Cor , Cinética , Fatores de Tempo
18.
Anim Sci J ; 91(1): e13410, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32583539

RESUMO

This study evaluates the effect of a low-voltage electrical stimulation (ES) on the tenderness of yak longissimus muscle (LM). Samples from 16 yak bulls were divided into four treatment groups: normal chilling (NC), ES and chilling (ES & C) for 72 s (ES &C 72 s), ES & C for 90 s (ES & C 90 s), and ES & C for 108 s (ES & C 108 s). The temperature, the pH, the glycogen content, the Warner-Bratzler shear force (WBSF), the myofibril fragmentation index (MFI), and the muscle ultrastructure were determined during the course of postmortem aging. ES caused a rapid decrease in the pH to form a high-temperature and low-pH environment. The glycogen content gradually decreased with aging. The WBSF value of the ES & C groups was significantly lower than for the NC group (p < .05). The MFI values of ES & C groups after 24 hr postmortem aging were significantly higher than for the NC group. We concluded that ES improved yak meat tenderness during postmortem aging and that the different duration time by ES indicated different effects, and its affect was remarkable in the ES & C 90 s.


Assuntos
Bovinos , Estimulação Elétrica/métodos , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Carne , Mudanças Depois da Morte , Animais , Temperatura Baixa , Armazenamento de Alimentos/métodos , Concentração de Íons de Hidrogênio , Masculino , Carne/análise , Músculo Esquelético/ultraestrutura , Polissacarídeos/análise , Fatores de Tempo
19.
Food Chem ; 324: 126903, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32361095

RESUMO

Cuticular wax chemicals differ among fruit cultivars and contribute to storage ability. However, wax analysis in apple cultivars, particularly during storage, has not been described. In this work, the chemicals and crystal structures of cuticular wax in 10 apple cultivars were analyzed to observe wax functions in apple during storage. Results showed that alkanes and primary alcohols decreased while fatty acids increased in stored fruits of all cultivars compared with the fruits before storage. Terpenoids, aldehydes, and phenols were observed in stored fruits but not in the fruits before storage in all cultivars except 'Red Star' fruit. The weight loss rate was significantly correlated with six components including C13 alcohol, C14 alkanes, total alkanes, total wax, C13 alkanes and C54 alkanes in 10 cultivar apple fruits during storage. Our findings indicate that the total wax, particularly alkanes, in the peel of apple fruits is essential for storage and quality control.


Assuntos
Armazenamento de Alimentos/métodos , Malus/química , Ceras/química , Álcoois/metabolismo , Aldeídos/análise , Alcanos/metabolismo , Ácidos Graxos/metabolismo , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Malus/metabolismo , Fenóis/análise , Terpenos/análise , Ceras/análise
20.
J Food Sci ; 85(6): 1699-1706, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32458467

RESUMO

The eight biogenic amines (BA), which are histamine (HIS), tryptamine, putrescine, 2-phenylethylamine, cadaverine, tyramine, spermidine, and spermine, were determined in Chub Mackerel under different storage conditions after being freshly caught. The storage time and temperature were varied and the guts either present or removed. This study describes a reverse-phase high-performance liquid chromatography (HPLC) with a fluorescence detector following precolumn derivation with dansyl chloride method for the determination of BA in in Chub Mackerel samples. HIS represented the highest content of BA regardless of the storage temperature and time. During a 24-hr period, the content of HIS reached its highest level of 6,466.63 mg/kg at the storage temperature of 30 °C, whereas it only reached 28.73 mg/kg in 24 hr when the storage temperature was 0 °C, which is way below the standard acceptable threshold level (400 mg/kg). The storage times for the content of HIS to exceed the standard threshold level for HIS at different storage temperatures of 0, 4, 10, 15, 20, and 25 °C were 12, 5, 4 days, 48, 36, 15, and 14 hr, respectively. However, these times were significantly shortened when the viscera was removed from freshly-caught fish before storage. This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method to extend the storage time of freshly-caught Chub Mackerel. PRACTICAL APPLICATION: This study not only provides data for monitoring the content of BA, especially HIS, to ensure the safe storage and consumption of freshly-caught Chub Mackerel, but also presents a cost-effective method, which is gut-removal during storage, to extend the storage time of freshly-caught Chub Mackerel.


Assuntos
Aminas Biogênicas/análise , Armazenamento de Alimentos/métodos , Carne/análise , Animais , Cadaverina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa , Histamina/análise , Perciformes
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