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1.
J Food Sci Technol ; 57(1): 364-374, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31975739

RESUMO

Grapefruit and lemon were exposed to phytosanitary irradiation doses of 0, 0.4, and 1 kGy, and then electronic-sensing screening of irradiation status and identification of radiation-induced ESR markers were conducted during 20 days storage. Codex standard photostimulated luminescence measurement (PSL1) was not a reliable indicator of irradiation status. Electronic tongue and electronic nose, however, showed potential as screening tools for discriminating irradiated fruits from non-irradiated counterparts based on principal component analysis of taste attributes and flavor patterns. Calibrated PSL approach clearly distinguished irradiated from non-irradiated samples based on the PSL ratio (PSL2/PSL1). Verification of irradiation status by electron spin resonance spectroscopy revealed clear paramagnetic centers from both irradiated fruits samples and ethanol-vacuum drying pretreatment improved radiation-induced ESR signal detection; not prominent enough in 0.4 kGy-irradiated commodities during 20 days of storage. Peel parts of both fruits showed high limonene which proportionally increased with irradiation doses (p < 0.05 kGy).

2.
J Sci Food Agric ; 99(2): 632-638, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29951995

RESUMO

BACKGROUND: Due to differences in radiation sources (electron beam from electron accelerator, gamma ray from 60 Co radionuclide) and energy delivery time (dose rate, kGy/time), the effects on foods are expected to be different with regard to chemical quality change and microbial decontamination. To better understand this impact, effects of variable dose rates of electron beam (EB, kGy s-1 ) and gamma rays (GR, kGy h-1 ) on microbial reduction, capsanthin content, and color parameters of red pepper (Capsicum annuum L.) powders (RPP) were determined. RPP samples were irradiated with 3 kGy absorbed dose, at variable dose rates of 1 and 5 kGy s-1 of EB (10 MeV/10 kW), and 1.8 and 9 kGy h-1 of GR (60 Co). RESULTS: Aerobic plate counts (APC) as well as yeast and mold counts of non-irradiated samples were 7.12 log CFU g-1 and 6.62 log CFU g-1 , respectively. EB and GR reduced these by 2-3 log CFU g-1 . A lower dose rate (1 kGy s-1 ) of EB was more effective for microbial reduction than a higher dose rate (5 kGy s-1 ). In contrast, a higher dose rate (9 kGy h-1 ) of GR efficiently decreased APC compared to a lower dose rate (1.8 kGy h-1 ). Higher EB and GR dose rates significantly decreased the capsanthin content and Hunter's red color (a* value). CONCLUSION: Low EB (kGy s-1 ) and high GR (kGy h-1 ) dose rates are recommended for microbiological safety of RPP with negligible changes in color attributes visible to the human eye, in contrast to the measured values. Thus the study demonstrates that the influence of absorbed dose is dependent on the applied dose rates. © 2018 Society of Chemical Industry.


Assuntos
Bactérias/efeitos da radiação , Capsicum/química , Capsicum/microbiologia , Irradiação de Alimentos/métodos , Frutas/efeitos da radiação , Pós/análise , Bactérias/crescimento & desenvolvimento , Capsicum/efeitos da radiação , Relação Dose-Resposta à Radiação , Frutas/química , Frutas/microbiologia , Raios gama
3.
J Sci Food Agric ; 99(8): 3860-3870, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30680730

RESUMO

BACKGROUND: In this study, we investigated whether electron beam (e-beam) irradiation can inactivate microbial populations, including aerobic bacteria plate count, fungi, and coliforms, in two types of lavers (dried and roasted). The impact of e-beam doses of 4 and 7 kGy on microbial populations, color values, total soluble pigments, chlorophylls, and carotenoid content immediately and after storage at 4, 15, 25, and 35 °C for 4, 8, and 12 weeks was also evaluated. RESULTS: The initial microbial load of approximately 106 and 105 CFU g-1 in both dried and roasted lavers was reduced to 104 and 101 CFU g-1 , respectively, after irradiation at 7 kGy. No further proliferation was observed in irradiated dried lavers during 4 weeks of storage at 4 and 15 °C. When stored at low temperature, the shelf-life was extended for up to 12 weeks in 7 kGy irradiated dried and roasted lavers. High amounts of soluble pigments and carotenoids were observed during storage in the 7 kGy irradiated dried laver samples at the end of 12 weeks irrespective of temperature. Although the chlorophyll content decreased under the storage conditions, it was comparatively stable in the 7 kGy-irradiated dried laver. Maximum degradation of color was observed in laver samples subjected to the roasting process. CONCLUSION: Overall, this study indicated that e-beam irradiation of laver at 7 kGy maintains microbial safety as well as quality attributes during storage for up to 12 weeks. Further, dried laver had more essential compounds than roasted laver. © 2019 Society of Chemical Industry.


Assuntos
Carotenoides/química , Clorofila/química , Irradiação de Alimentos/métodos , Pigmentos Biológicos/química , Extratos Vegetais/química , Porphyra/química , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/efeitos da radiação , Temperatura Baixa , Armazenamento de Alimentos , Humanos , Folhas de Planta/química , Folhas de Planta/microbiologia , Porphyra/microbiologia , Controle de Qualidade , Paladar
4.
J Food Sci Technol ; 56(12): 5454-5464, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31749493

RESUMO

This study focuses on applicability of e-sensing methods in addition to direct epifluorescent filter technique (DEFT), aerobic plate counts (APC), and photostimulated luminescence (PSL) to discriminate e-beam, γ-ray, and X-ray irradiated green onions (scallions) at 1, 4, and 7 kGy for each irradiation treatment, along with two confirmatory analysis. Although low dose (1 kGy) reduced the APC (6.15-2.69 log CFU/g), no significant difference was observed in DEFT. Scallions with log DEFT/APC ratio of ≥ 5.2 can be suspected as irradiated at at least 1 kGy. Both non-irradiated (< 700 counts/min) and irradiated (> 5000 counts/min) scallions were identified by PSL. Besides distinct volatile compounds profile, cumulative e-nose discrimination of 92.06% from principle component analysis was apparent among irradiation conditions. Sensitivity to changes in perceived taste by e-tongue showed 96.07% variation. The e-sensing capability to discriminate irradiated scallions can be exploited for exposing counterfeit claims as either non-irradiated or irradiated within the recommended standards.

5.
Lipids Health Dis ; 17(1): 223, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30249252

RESUMO

Ruminant meat flavor is an important quality and sensory parameter which relays mainly on the organoleptic characteristics of meat. Meat flavor is vital factor for the palatability and acceptability of meat by the consumers. There are various intrinsic and extrinsic factors that influence eating quality of meat. Among these factors, flavor is the major contributor. Fat and low-molecular-weight water-soluble compounds are the most important precursor components in meat, responsible for the meat flavor. The present review focus on the different pre and post-harvest factors that influences the ruminant meat flavor. Raw meat has little flavor but cooking adds value in flavor due to different temperature and cooking methods. The volatile flavoring compounds which are responsible for cooked meat flavor are produced thermally by the Maillard's reaction itself or interaction with lipid oxidation products and vitamin degradation. In nutshell, this review provides perception into previous literature on flavor that affected by various factors particularly the fatty acids and cooking methods.


Assuntos
Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos , Carne , Paladar , Animais , Culinária , Ácidos Graxos/química , Ácidos Graxos/fisiologia , Humanos , Oxirredução , Ruminantes/metabolismo
6.
J Sci Food Agric ; 98(14): 5444-5449, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29675926

RESUMO

BACKGROUND: High microbial load is a serious concern in terms of the health-related safety of products of animal origin. In this study, the microbial loads of commercial frozen duck-meat products, including bone-in whole raw, boneless sliced raw, and boneless whole smoked, were investigated for pathogenic contamination. The application of electron beam irradiation was also investigated. RESULTS: The samples revealed a serious microbial threat (102 -105 CFU g-1 for total aerobic bacteria and positive for foodborne pathogens), which required effective decontamination technology. Electron-beam irradiation (0, 1, 3, and 7 kGy) could potentially improve the hygienic quality of duck-meat samples. The D10 values for Listeria monocytogenes and Salmonella Typhi were 0.47 and 0.51 kGy, respectively. A direct epifluorescent filter technique and aerobic plate count (DEFT/APC) method was used for screening, while electron-spin resonance (ESR) spectroscopy and gas chromatography with mass spectrometry were effective as confirmatory techniques to identify radiation-induced markers in frozen duck meat. CONCLUSION: Electron-beam irradiation has the potential to ensure the microbial safety and hygienic quality of commercial duck meats. Identification of the samples for their irradiation history was also possible using radiation-induced detection markers, including the DEFT/APC, hydroxyapatite ESR radicals, and hydrocarbons. © 2018 Society of Chemical Industry.


Assuntos
Contaminação de Alimentos/prevenção & controle , Irradiação de Alimentos/métodos , Produtos da Carne/microbiologia , Animais , Patos , Contaminação de Alimentos/análise , Irradiação de Alimentos/instrumentação , Microbiologia de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/efeitos da radiação , Produtos da Carne/efeitos da radiação , Controle de Qualidade , Salmonella typhi/crescimento & desenvolvimento , Salmonella typhi/efeitos da radiação
7.
J Food Sci Technol ; 55(10): 3902-3910, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30228388

RESUMO

The application of food irradiation is based on the parameters including energy (MeV), dose rate (kGy/s or kGy/h), and absorbed dose (kGy). Red pepper powders were treated with different dose rates of 1, and 5 kGy/s electron beam (EB) as well as 1.8 and 9 kGy/h gamma ray (GR) in separate experiments. Constant absorbed dose (3 kGy) was maintained to observe whether different dose rates affect the product quality. Total and individual capsaicinoids increased at low EB and GR dose rates. Vitamin C content decreased at all dose rates, except at low GR dose rate, where no significant difference was observed. Low EB dose rate led to a marked increase (21%) in the total phenolics than high dose rate (13%). In contrast, high GR dose rate increased the total phenolics than low dose rate. Maximum antioxidants (1.36 mg TE/mL) were observed at high EB dose rate, although low dose rate also increased the antioxidant activity. Results indicated that different dose rates delivering the same absorbed dose had significant impact on the product quality and that the efficacy of absorbed dose is dependent on applied dose rates. In other words, a constant absorbed dose applied to the product is influenced by dose rate of the irradiation treatment.

8.
Lipids Health Dis ; 16(1): 84, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28464819

RESUMO

The current review article is an attempt to explain the therapeutic potential of mangiferin, a bioactive compound of the mango, against lifestyle-related disorders. Mangiferin (2-ß-D-glucopyranosyl-1,3,6,7-tetrahydroxy-9H-xanthen-9-one) can be isolated from higher plants as well as the mango fruit and their byproducts (i.e. peel, seed, and kernel). It possesses several health endorsing properties such as antioxidant, antimicrobial, antidiabetic, antiallergic, anticancer, hypocholesterolemic, and immunomodulatory. It suppresses the activation of peroxisome proliferator activated receptor isoforms by changing the transcription process. Mangiferin protects against different human cancers, including lung, colon, breast, and neuronal cancers, through the suppression of tumor necrosis factor α expression, inducible nitric oxide synthase potential, and proliferation and induction of apoptosis. It also protects against neural and breast cancers by suppressing the expression of matrix metalloproteinase (MMP)-9 and MMP-7 and inhibiting enzymatic activity, metastatic potential, and activation of the ß-catenin pathway. It has the capacity to block lipid peroxidation, in order to provide a shielding effect against physiological threats. Additionally, mangiferin enhances the capacity of the monocyte-macrophage system and possesses antibacterial activity against gram-positive and gram-negative bacteria. This review summarizes the literature pertaining to mangiferin and its associated health claims.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Antioxidantes/uso terapêutico , Hipoglicemiantes/uso terapêutico , Nootrópicos/uso terapêutico , Xantonas/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/patologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/patologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Humanos , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/patologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Mangifera/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neuralgia/tratamento farmacológico , Neuralgia/patologia , Nootrópicos/química , Nootrópicos/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Xantonas/química , Xantonas/isolamento & purificação
9.
Lipids Health Dis ; 16(1): 108, 2017 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-28595582

RESUMO

BACKGROUND: Current day consumers prefer natural antioxidants to synthetic antioxidants because they are more active. However, the activity generally depends on the specific condition and composition of food. The aim of this study was to investigate the effect of wheat germ oil and α-lipoic acid on the quality characteristics, antioxidant status, fatty acid profile, and sensory attributes of chicken nuggets. METHODS: Six types of diets were prepared for feeding the chickens to evaluate the quality of nuggets made from the leg meat of these experimental animals. These included control, diet enriched with wheat germ oil (WGO), which is a rich natural source of α-tocopherol (AT), diet with added AT or α-lipoic acid (ALA), diet with a combination of either ALA and WGO (ALA + WGO) or ALA and synthetic AT (ALA + AT). ALA has great synergism with synthetic as well as natural AT (WGO). RESULTS: The diet with WGO and ALA showed the best potential with respect to both antioxidant activity and total phenolic content. HPLC results revealed that the chicken nuggets made from WGO + ALA group showed maximum deposition of AT and ALA. The stability of the nuggets from control group was found to be significantly lower than that of nuggets from the WGO + ALA group. Total fatty acid content too was higher in the nuggets from this group. The poly unsaturated fatty acids (PUFA) were found to be higher in the nuggets from the groups fed with a combination of natural and synthetic antioxidants. CONCLUSION: It is concluded that the combination of natural and synthetic antioxidants in the animal feed exerts a synergistic effect in enhancing the stability and quality of chicken nuggets.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Carne/análise , Óleos de Plantas/administração & dosagem , Ácido Tióctico/administração & dosagem , Ração Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta , Ácidos Graxos/química , Ácidos Graxos/metabolismo
10.
Compr Rev Food Sci Food Saf ; 16(2): 295-315, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33371540

RESUMO

Polyphenols as phytochemicals have gained significant importance owing to several associated health benefits with regard to lifestyle diseases and oxidative stress. To date, the development of a single standard method for efficient and rapid extraction of polyphenols from plant matrices has remained a challenge due to the inherent limitations of various conventional extraction methods. The exploitation of polyphenols as bioactive compounds at various commercial levels has motivated scientists to explore more eco-friendly, efficient, and cost-effective extraction techniques, based on a green extraction approach. The current review aims to provide updated technical information about extraction mechanisms, their advantages and disadvantages, and factors affecting efficiencies, and also presents a comparative overview of applications of the following modern green extraction techniques-supercritical fluid extraction, ultrasound-assisted extraction, microwave-assisted extraction, pressurized liquid extraction, and pressurized hot water extraction-as alternatives to conventional extraction methods for polyphenol extraction. These techniques are proving to be promising for the extraction of thermolabile phenolic compounds due to their advantages over conventional, time-consuming, and laborious extraction techniques, such as reduced solvent use and time and energy consumption and higher recovery rates with lower operational costs. The growing interest in plant-derived polyphenols prompts continual search for green and economically feasible modern extraction techniques. Modern green extraction techniques represent promising approaches by virtue of overcoming current limitations to the exploitation of polyphenols as bioactive compounds to explore their wide-reaching applications on an industrial scale and in emerging global markets. Future research is needed in order to remove the technical barriers to scale-up the processes for industrial needs by increasing our understanding and improving the design of modern extraction operations.

11.
Crit Rev Food Sci Nutr ; 56(11): 1790-807, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-25830470

RESUMO

Development of knowledge-based food preservation techniques have been a major focus of researchers in providing safe and nutritious food. Food irradiation is one of the most thoroughly investigated food preservation techniques, which has been shown to be effective and safe through extensive research. This process involves exposing food to ionizing radiations in order to destroy microorganisms or insects that might be present on and/or in the food. In addition, the effects of irradiation on the enzymatic activity and improvement of functional properties in food have also been well established. In the present review, the potential of food irradiation technology to address major problems, such as short shelf life, high-initial microbial loads, insect pest management (quarantine treatment) in supply chain, and safe consumption of fresh fruits was described. With improved hygienic quality, other uses, such as delayed ripening and enhanced physical appearance by irradiation were also discussed. Available data showed that the irradiation of fruits at the optimum dose can be a safe and cost-effective method, resulting in enhanced shelf life and hygienic quality with the least amount of compromise on the various nutritional attributes, whereas the consumer acceptance of irradiated fruits is a matter of providing the proper scientific information.


Assuntos
Comportamento do Consumidor , Irradiação de Alimentos , Inocuidade dos Alimentos , Frutas/efeitos da radiação , Valor Nutritivo , Fenômenos Químicos , Frutas/química , Humanos
12.
Anal Bioanal Chem ; 405(12): 4225-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23503732

RESUMO

Two kinds (20 each) of gamma-irradiated (0, 5, and 10 kGy) tea samples, blended powders and packed in sachets (tea bags), were investigated using photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance spectroscopy (ESR) to identify their irradiation status. PSL-based rapid screening was possible for all the control samples except for one packed and two powdered samples. The irradiated samples presented a good dose-dependent PSL count except two powdered samples with very low PSL sensitivity. TL analysis provided the most reliable results, in which all the irradiated samples were identified using a well-defined high-intensity TL glow curve in a temperature range of 150-250 °C. The TL results were also confirmed by determining the TL ratio (TL1/TL2), which was <0.1 in all the non-irradiated samples and >0.1 in the irradiated ones. ESR spectroscopy was effective for only 3 packed and 6 powdered samples showing the radiation-induced cellulosic and sugar radical signals, respectively.


Assuntos
Irradiação de Alimentos/métodos , Radicais Livres/análise , Chá/química , Chá/efeitos da radiação , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama , Luminescência , Medições Luminescentes
13.
J Sci Food Agric ; 93(3): 634-40, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22969007

RESUMO

BACKGROUND: The general use of food irradiation requires reliable identification methods as well as extensive quality characterization. Shiitake (Lentinus edodes) mushrooms, packed in polystyrene trays and covered with polyvinylchloride film, were investigated for dose-dependent identification and quality characterization upon gamma irradiation (0, 1, 2, and 3 kGy). RESULTS: Thermoluminescence (TL) analysis of separated minerals provided excellent results to characterize the irradiated mushrooms. Low-dose re-irradiation (200-600 Gy), medium-dose re-irradiation (1-3 kGy) and high-dose re-irradiation (2-6 kGy) were performed and compared using an additive dose method. An electronic-nose analysis showed a difference in the volatile profiles of mushrooms following irradiation. One-kGy-irradiated mushrooms showed similar or better quality attributes to those of the control samples. Scanning electron microscopy revealed the dose-dependent degradation in microstructure of mushrooms upon irradiation. CONCLUSION: An absorbed dosed estimation was possible using TL analysis in which 1-3 kGy re-irradiation technique gave most promising results. An E-nose analysis effectively distinguished the samples based on irradiation history. The best quality attributes were observed at 1 kGy irradiation. However, the drastic effects of irradiation were prominent in 2 and 3 kGy-irradiated mushrooms.


Assuntos
Irradiação de Alimentos , Cogumelos Shiitake/efeitos da radiação , Cor , Relação Dose-Resposta à Radiação , Conservação de Alimentos/métodos , Raios gama , Microscopia Eletrônica de Varredura , Cogumelos Shiitake/química , Cogumelos Shiitake/ultraestrutura , Compostos Orgânicos Voláteis/análise
14.
J Sci Food Agric ; 92(4): 759-63, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22413144

RESUMO

BACKGROUND: Gamma irradiation is a safe method for the decontamination of shellfish, and its technical feasibility and safety have been endorsed (FAO/IAEA/WHO). In order to implement proper food-processing regulations, the identification of radiation treatment is required. In this study, electron paramagnetic resonance (EPR) spectroscopy was employed to identify the irradiation of seven different types of commonly consumed shellfish. RESULTS: Characteristics (g factor and signal intensity) of the EPR spectra of control and irradiated samples were recorded in order to clarify the gamma-ray treatment of shellfish. Radiation-specific signals around g = 2.0038 ± 0.0006 (g1) and g = 1.9996 ± 0.0002 (g2 and g3) were observed for all shellfish samples irradiated with absorbed doses of 3 and 6 kGy. The X-ray diffraction (XRD) spectra of some shellfish samples were recorded to investigate their mineral profiles. CONCLUSION: The EPR spectroscopic results indicated that carbonate minerals were the source of the paramagnetic species that were produced upon irradiation, entrapped in the shellfish and showed radiation-specific asymmetric signals whose intensities increased quantitatively with the absorbed radiation dose. The XRD analysis revealed that aragonite and calcite minerals were present in the shells of shellfish.


Assuntos
Exoesqueleto/efeitos da radiação , Irradiação de Alimentos , Radicais Livres/análise , Raios gama , Moluscos/efeitos da radiação , Frutos do Mar/efeitos da radiação , Exoesqueleto/química , Animais , Carbonato de Cálcio/análise , Espectroscopia de Ressonância de Spin Eletrônica , Inspeção de Alimentos/métodos , Minerais/análise , Moluscos/química , Doses de Radiação , República da Coreia , Frutos do Mar/análise , Difração de Raios X
15.
J Sci Food Agric ; 92(8): 1780-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22227835

RESUMO

BACKGROUND: Consumer preference for selection of natural substances, with their safe and beneficial effects on the human body as well as various physiological efficacies, is increasing. In this study, response surface methodology (RSM) was used to monitor the extraction characteristics of Vitis coignetiae (wild grape) and thereby optimise the functional properties of the resulting extract. RESULTS: A maximum total polyphenol content (TPC) of 415.74 mg per 100 g was obtained at a microwave power (MWP) of 102.36 W, an ethanol concentration (ETC) of 42.62% (by volume) and an extraction time (EXT) of 12.35 min. Electron-donating ability (EDA) reached a maximum of 69.20% at 125.65 W MWP, 41.81% ETC and 13.65 min EXT. The maximum nitrite-scavenging ability (NSA) obtained was 87.50% at 119.13 W MWP, 37.41% ETC and 13.20 min EXT. Superoxide dismutase (SOD) showed a maximum pseudo-activity (SDA) of 56.74% at 69.54 W MWP, 94.88% ETC and 10.32 min EXT. The effect of ETC was most prominent among the studied factors. CONCLUSION: Based on the superimposition of four-dimensional response surfaces with respect to TPC, EDA, NSA and SDA, the optimum ranges of extraction conditions were 70-150 W MWP, 30-50% ETC and 8-18 min EXT.


Assuntos
Antioxidantes/análise , Frutas/química , Micro-Ondas , Extratos Vegetais/química , Polifenóis/análise , Vitis/química , Antioxidantes/metabolismo , Interpretação Estatística de Dados , Alimento Funcional , Humanos , Nitritos/metabolismo , Superóxido Dismutase/metabolismo
16.
J Sci Food Agric ; 90(1): 30-5, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20355008

RESUMO

BACKGROUND: Perilla and sesame seeds, a rich source of energy, are commonly utilized in different forms in many countries. During the post-harvest period, they are contaminated with insects as well as microbes that may have importance for keeping quality and quarantine, and thus they can be treated with ionizing radiation for insect disinfestation and microbial decontamination. Reliable and routine methods to identify whether or not a food has been irradiated are needed to help consumers' understanding of irradiated food and promote international trade. In the present study, fat-derived hydrocarbons from irradiated perilla seeds and sesame seeds of Korean and Chinese origin were analyzed in order to identify irradiation treatment by comparing their properties during the post-irradiation period. RESULTS: Gas chromatographic-mass spectrometric analysis showed that several saturated hydrocarbons, such as tetradecane, pentadecane, hexadecane and heptadecane, were found in the non-irradiated control samples, while four radiation-induced unsaturated hydrocarbons (R(2) = 0.647-0.997), such as 1,7,10-hexadecatriene (C(16:3)), 1,7-hexadecadiene (C(16:2)), 6,9-heptadecadiene (C(17:2)) and 8-heptadecene (C(17:1)), were detected in all irradiated samples at 0.5 kGy or higher, with variations according to sample and origin. Concentrations of all hydrocarbons were reduced during storage and could not be detected in 0.5 kGy irradiated Chinese sample of either seed after 8 months. CONCLUSION: Radiation-induced hydrocarbons (C(16:3, 16:2, 17:2, 17:1)) could be used as markers to identify irradiated perilla and sesame seeds of both Korean and Chinese origin at 1 kGy or higher for 8 months' storage at room temperature.


Assuntos
Irradiação de Alimentos , Conservação de Alimentos/métodos , Hidrocarbonetos/análise , Perilla/efeitos da radiação , Sementes/efeitos da radiação , Sesamum/efeitos da radiação , Animais , Manipulação de Alimentos , Microbiologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Insetos/efeitos da radiação , Perilla/química , Radiação Ionizante , Sementes/química , Sesamum/química
17.
Food Sci Nutr ; 8(2): 1020-1029, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32148810

RESUMO

This study investigated the effect of different doses (0, 3, and 7 kGy) of e-beam on the microbiological and physicochemical qualities and the profile of fatty acids of the frozen duck meat (FDM). Electron beam at the dose of 3 kGy showed more than 2 log and 1 log cycles of reduction in the total bacterial (TAB) and coliform counts (TCC), respectively. The results indicated an increase in the TBARS values (1.50 ± 0.02 mg MDA/kg), peroxide value (0.83 ± 0.04 meq peroxide/kg), and total volatile base nitrogen (1.31 ± 0.16 mg/100 ml), but no effect on the sensory parameters. Irradiation lowered the lightness (L*) (31.87 ± 0.98) and redness (a*) (11.04 ± 0.20) values but elevated the metmyoglobin content in FDM. In addition, irradiation had no effect on the benzopyrene content; however, a reduction was observed in the vitamin A (0.239 ± 0.015 µg/g) and vitamin E (1.847 ± 0.075 µg/g) contents of the FDM samples. There were no trans-fatty acids present in the treated (irradiated) as well as the untreated (nonirradiated) meat samples (FDM), whereas the fatty acid content decreased in irradiated samples, in contrast with the nonirradiated control. Electronic nose clearly discriminated between the nonirradiated and irradiated FDM based on principal component analysis. It is concluded that the e-beam successfully improved the microbial quality of FDM with slight changes in physicochemical properties, but without altering its sensory properties.

18.
Food Sci Biotechnol ; 29(5): 705-715, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32419969

RESUMO

Medicinal herbs comprise of heavy microbial contaminations. This study aimed to assess microbial hazards including foodborne pathogens in 20 commercial medicinal herbs, Cnidii Rhizoma (C1-C10) and Alismatis Rhizoma (T1-T10) as well as to evaluate irradiation effects of E-beam on microbial load and detection chracteristics. Four samples (C5, C10, T1, T8) from both herbs with higher microbial load were selected for evaluating the irradiation effect of E-beam (up to 10 kGy) on microbial load and radiation-induced changes in detection markers by standard methods (Codex, Korean Food Code), such as direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR). DEFT/APC revealed non-evidence of pre-sterilization of all samples. PSL differentiated irradiated samples (1, 5, and 10 kGy) of both herbs from non-irradiated (control: 0 kGy). Both TL and ESR methods validated PSL screening results by detecting radiation-induced markers from E-beam irradiated medicinal herbs.

19.
Food Chem ; 286: 338-345, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827616

RESUMO

Consumption and global utilization of mandarins is on the rise due to its easy-to-peel attribute compared to other citrus fruits. Mandarins are irradiated as an effective phyto-sanitary treatment for trade requirements. In this study, mandarins were irradiated with 0.4 and 1 kGy electron-beam as approved by United States Department of Agriculture (USDA), and changes in microbial and physicochemical characteristics during storage were monitored at 4 °C for 15 d. Microbial proliferation during storage was noticeable in non-irradiated fruits, whereas irradiated mandarins showed dose-dependent inhibition up to 15 d. Irradiation did not affect its moisture, total phenolics, and vitamin C. However, hardness, organic acids, hesperidin, radical scavenging activity, reducing and free sugars significantly decreased in all samples after 5 d of storage. Although, irradiation at 0.4 and 1 kGy could not prevent changes in stored mandarins, 0.4 kGy did not affect the major constituents and physical quality of mandarins, while providing microbial decontamination.


Assuntos
Citrus sinensis/efeitos da radiação , Irradiação de Alimentos/métodos , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Citrus sinensis/metabolismo , Elétrons , Sequestradores de Radicais Livres/química , Frutas/metabolismo , Frutas/efeitos da radiação , Hesperidina/análise , Fenóis/análise , Temperatura
20.
Food Chem ; 286: 395-404, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827624

RESUMO

Rapid analytical methods for screening irradiated foods are required to comply with the approved standards for international trade. Dried shrimps irradiated at 1-7 kGy with gamma rays, electron beam (E-beam), and X-rays were screened with an electronic nose (E-nose) and electronic tongue (E-tongue). The data were compared with those from European standard methods (photostimulated luminescence, PSL) and direct epifluorescent filter technique/aerobic plate count, DEFT/APC). All irradiated shrimp samples were clearly discriminated from the non-irradiated control based on PSL photon count measurements and DEFT/APC microbial enumeration. The volatile patterns and taste attributes of the irradiated (>1 kGy from three sources) and control samples could be distinguished by the E-nose and E-tongue analyses through principal component analysis. Verification through electron spin resonance and thermoluminescence analyses validated screening results. The results indicate that E-sensing techniques showed potential for the rapid screening of irradiated foods like dried shrimps.


Assuntos
Análise de Alimentos/métodos , Irradiação de Alimentos , Frutos do Mar/análise , Espectroscopia de Ressonância de Spin Eletrônica , Nariz Eletrônico , Eletrônica/instrumentação , Eletrônica/métodos , Análise de Alimentos/instrumentação , Raios gama , Medições Luminescentes/métodos , Raios X
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