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1.
J Agric Food Chem ; 67(41): 11454-11463, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529950

RESUMO

Commercial fragrant rapeseed oil (CFRO), from roasted and hot-pressed seeds, is enjoyed in China for its unique aroma. However, the characteristic of aroma-active compounds in CFRO is still unclear. In this study, a new odor monolithic material sorptive extraction method was established to trap volatiles from rapeseed oil. Thirty CFROs were investigated using this method coupled with gas chromatography-mass spectrometry. A total of 29 volatile compounds were identified by gas chromatography-olfactometry including pyrazines, alcohols, aldehydes, ketones, and sulfur compounds. Further, 2,5-dimethylpyrazine (peanut-like), 3-ethyl-2,5-dimethylpyrazine (roasted nut-like), dimethyl trisulfide (cabbage-like), 4-isothiocyanato-1-butene (pungent and pickle-like), butyrolactone (caramel-like), and benzyl nitrile (pungent and sulfur-like) are affirmed as the key odorants for the overall aroma of CFRO, owing to their odor activity values ≥1. This work provides a new insight on acquiring aroma-active compounds from rapeseed oil in a more time-effective process compared to conventional methods. Futhermore, this novel approach is applicable in the field of food flavor.


Assuntos
Aromatizantes/química , Odorantes/análise , Óleo de Brassica napus/química , Compostos Orgânicos Voláteis/química , Adsorção , Aromatizantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Olfatometria , Óleo de Brassica napus/economia , Sementes/química , Extração em Fase Sólida , Compostos Orgânicos Voláteis/isolamento & purificação
2.
J Agric Food Chem ; 67(37): 10401-10411, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31441654

RESUMO

This research applied inhibitors to reduce the content of cooked off-flavor components (dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, and 3-(methylthio)propanaldehyde) in heat-treated melon juice. The effects of glucose oxidase (GOD) on the formation and release of these four volatile sulfur compounds were also investigated. Results showed that GOD strongly inhibited the formation of the four compounds. In GOD-treated melon juice, S-methylmethionine was strongly protonated and not easily degraded into dimethyl sulfide. Moreover, the release of the dimethyl sulfide that did form was restrained by the hydrophobic interactions of gluconic acid and oxidation by hydrogen peroxide. In addition, gluconic acid (or glucose) and hydrogen peroxide could form a stable complex with methionine in an acidic matrix and thus prevented the methionine from producing 3-(methylthio)propanaldehyde, dimethyl disulfide, and dimethyl trisulfide by the Maillard reaction during heat processing.


Assuntos
Cucurbitaceae/química , Aromatizantes/química , Sucos de Frutas e Vegetais/análise , Culinária , Cucurbitaceae/enzimologia , Frutas/química , Frutas/enzimologia , Glucose Oxidase/química , Temperatura Alta , Humanos , Reação de Maillard , Odorantes/análise , Proteínas de Plantas/química , Compostos de Enxofre/química , Paladar
3.
J Agric Food Chem ; 67(38): 10713-10725, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31453702

RESUMO

Converting peanut protein biomass waste into environmentally friendly meat substitutes by a high-moisture extrusion process can help solve both resource and waste problems and be "double green". A multiscale method combined with some emerging techniques such as atomic force microscopy-based infrared spectroscopy and X-ray microscopy was used to make the whole extrusion process visible to show the process of forming a meat-like fibrous structure using two-dimensional and three-dimensional perspectives. The results showed that the protein molecules underwent dramatic structural changes and unfolded in the extruder barrel, which created favorable conditions for molecular rearrangement in the subsequent zones. It was confirmed that the meat-like fibrous structure started to form at the junction of the die and the cooling zone and that this structure was caused by the phase separation and rearrangement of protein molecules in the cooling zone. Moreover, the interactions between hydrogen bonds and disulfide bonds formed in the cooling zone maintained the meat-like fibrous structure with an α-helix > ß-sheet > ß-turn > random coil. Of the two main peanut proteins, arachin played a greater role in forming the fibrous structure than conarachin, especially those subunits of arachin with a molecular weight of 42, 39, and 22 kDa.


Assuntos
Arachis/química , Aromatizantes/química , Extratos Vegetais/química , Proteínas de Plantas/química , Resíduos/análise , Aromatizantes/isolamento & purificação , Química Verde , Ligações de Hidrogênio , Raios Infravermelhos , Extratos Vegetais/isolamento & purificação , Conformação Proteica
4.
J Agric Food Chem ; 67(36): 10137-10144, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423769

RESUMO

Volatile extractive compounds from high-quality oak wood (Quercus sp.) are responsible for important pleasant olfactory notes, such as coconut, wood, vanilla, caramel, and spice. Recently, a new off-flavor reminiscent of rancid butter has been detected in oak wood. Using gas chromatography-olfactometry (GC-O) coupled to several detection modes, such as nitrogen-phosphorus detection (GC-O-NPD) or mass spectrometry (GC-O-MS) and multidimensional GC-O coupled to time-of-flight mass spectrometry, six compounds containing nitrogen atoms were identified. The volatiles were suggested to belong to 2,5-disubstituted pyrazines family, which was confirmed by comparison with synthetic reference compounds. For this purpose, symmetric and dissymmetric 2,5-dialkylpyrazines were prepared from methyl esters of corresponding aliphatic amino acids (Val, Leu, and Ile) by a three-step, one-pot reaction under mild reducing conditions. Organoleptic descriptors and odor detection thresholds were also determined, whereas a bacterial origin explaining these off-flavors was hypothesized.


Assuntos
Aromatizantes/química , Pirazinas/química , Quercus/química , Madeira/química , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria
5.
J Agric Food Chem ; 67(36): 10195-10206, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31436982

RESUMO

Pea protein hydrolysate (PPH) is successfully conjugated with gum arabic (GA) through Maillard-driven chemistry. The effect of cross-linking conjugation on the structure, solubility, volatile substances, emulsification, and antioxidative activity of glyco-PPH is investigated, and found to improve all properties. The formation of glyco-PPH is confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM). Size exclusion chromatography-multi angle light scattering (SEC-MALS) unveils that the maximum molecular mass of glyco-PPH occurs after 1 day of conjugation and approximately 1.2 mol of gum arabic conjugates on one mole of PPH. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) reveals the odor changes of glycoprotein before and after cross-linking. We have also prepared oil-in-water emulsions using glyco-PPH, which have enhanced physical stability against pH changes and chemical stability against lipid oxidation. The mechanism proposed involves Maillard-driven synthesis of the cross-linked PPH-GA conjugates, which increase the surface hydrophilicity and steric hindrance of glyco-PPH. These findings could provide a rational foundation for tailoring the physicochemical properties and functionalities of plant-based protein, which are attractive for food and functional materials applications.


Assuntos
Aromatizantes/síntese química , Goma Arábica/química , Proteínas de Ervilha/química , Antioxidantes/química , Emulsões/química , Aromatizantes/química , Interações Hidrofóbicas e Hidrofílicas , Reação de Maillard , Hidrolisados de Proteína/química , Solubilidade
6.
J Agric Food Chem ; 67(31): 8599-8608, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287302

RESUMO

Because foods are perceived through combined inputs from taste and odor, which are determined by the concentration of the individual odor and taste molecules, the unified high-throughput quantitation of volatile odorants and non-volatile tastants with the very same instrumental setup has been a long-standing but yet unmet dream. The research presented here for the first time demonstrates, after only minimal sample workup, the highly accurate, rapid, and sensitive unified quantitation of odorants and tastants of key flavor molecules in apple juice on a single ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) platform over a large dynamic range of up to 6 orders of magnitude. While flavor-active aldehydes, ketones, and organic acids were analyzed after derivatization with 3-nitrophenylhydrazine, taste-active polyphenols and odor-active esters were directly analyzed by means of UHPLC-MS/MS with and without target analyte enrichment through stir-bar sorptive extraction. This "unified flavor quantitation" approach holds promise to accelerate the transition of today's labor and time-consuming, low-throughput analysis of odorants and tastants into a new era of high-performance quantitation of key flavor molecules.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Aromatizantes/química , Ensaios de Triagem em Larga Escala/métodos , Odorantes/análise , Espectrometria de Massas em Tandem/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Compostos Orgânicos Voláteis/química
7.
Food Chem ; 300: 125195, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326676

RESUMO

Presence of pungent gingerols in ginger oleoresin makes it an ideal natural flavoring candidate for the food industry. The study reports its incorporation for synergistic enhancement of flavor and nutraceutical portfolio of candied mango. The process is systematically optimized at bench-scale for gingerols infusion and subsequent candying treatment in a range of hypo and hypertonic osmotic solutions for critical transport properties. After that, optimization of the drying process and the scale-up study was conducted with a 200 folds increase in the batch size. Collated effects of multistep optimization resulted in 85.6, 76.8, 60.2% retention in ß-carotene, total phenolics, Vitamin C, respectively, along with minor color difference and significant improvement in sensory scores over fresh mango. Mass transfer and quality parameters were comparable in both scales, implying excellent repeatability and scalability of the process. Compared with a similar commercial product, substantial improvement in quality characteristics along with 376.7% reduction in overall processing time was achieved.


Assuntos
Doces , Catecóis/química , Álcoois Graxos/química , Aromatizantes/química , Indústria de Processamento de Alimentos/métodos , Mangifera/química , Ácido Ascórbico/análise , Ácido Ascórbico/química , Cor , Dessecação/métodos , Suplementos Nutricionais/análise , Qualidade dos Alimentos , Frutas/química , Gengibre/química , Humanos , Fenóis/análise , Fenóis/química , Paladar , beta Caroteno/análise , beta Caroteno/química
8.
J Food Sci ; 84(8): 2171-2180, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313307

RESUMO

Amadori rearrangement product (ARP) derived from glutamic acid (Glu) and xylose (Xyl) was prepared by aqueous Maillard reaction. Subsequently, ion exchange chromatography, MS, and NMR were used for purification and identification, confirming that the molecular formula of ARP was C10 H17 NO8 , namely N-(1-deoxy-α-D-xylulos-1-yl)-glutamic acid, with a molecular mass of 279 Da. To improve the aqueous yield of ARP, a thermal reaction coupled with vacuum dehydration was used and the yield of ARP was increased from 2.07% to 75.11%. Furthermore, flavor formation capacity of ARP by a thermal treatment simulated to a baking process was compared with Maillard reaction products, Maillard-dehydration reaction products, and Glu-Xyl mixture. The results indicated that a larger amount of volatile flavor compounds and a biscuit-like, burnt aroma was generated rapidly from the mixture of ARP and unreacted Glu-Xyl, which could be a potential flavor enhancer for baked foods. PRACTICAL APPLICATION: Maillard reaction performed in aqueous medium through thermal reaction combined with vacuum dehydration is a novel and practical technology that could be widely used to produce Maillard reaction intermediates (MRIs), such as Amadori or Heyns rearrangement products, which are regarded as significant nonvolatile aroma precursors and have stable physical and chemical properties compared with Maillard reaction products (MRPs). MRI derived from glutamic acid and xylose is a potential substitute of MRPs for flavorings preparation and shows a great capacity to generate fresh flavors in a short time at high temperature, which meets the requirements of baking foods. Therefore, the new developed method could be a promising tool for MRI preparation and application in food and flavoring industries.


Assuntos
Aromatizantes/química , Ácido Glutâmico/química , Produtos Finais de Glicação Avançada/química , Temperatura Alta , Reação de Maillard , Odorantes/análise , Paladar , Vácuo , Xilose/química
9.
J Sci Food Agric ; 99(14): 6444-6454, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31294830

RESUMO

BACKGROUND: There is a close relationship between certain 'aging markers' in wine and the wine's age. This study aimed to characterize all extracted aging markers in Chinese rice wine and distinguish the ages of Chinese rice wine using principal component analysis (PCA) and cluster analysis (CA). RESULTS: A total of 49 potential aging markers (P ≤ 0.05*) were extracted from 71 volatile organic compounds (VOCs) in Chinese rice wine across a range of seven different ages. Of all 49 extracted aging markers, all furans, 2/3 aldehydes and ketones maintained significantly increasing levels with age (P ≤ 0.01**), especially sotolon (0.981**) and acetophenone (0.951**). On the other hand, all sulfides decreased significantly (P ≤ 0.01**). Changes in vanillin, guaiacol, 4-vinylguaiacol (4-VG) and 4-ethylguaiacol (4-EG) also suggested a potential synthesis during the aging process. The results of PCA and CA demonstrated that Chinese rice wines with different ages could be clearly distinguished from each other, which was consistent with the evolution of the 49 aging markers during the aging process. CONCLUSION: These 49 potential 'aging markers' successfully distinguished ages using PCA and CA. Our results therefore throw light on the characterization of VOCs during Chinese rice wine aging, and provide a quantitative basis for discriminating the ages of Chinese rice wine. © 2019 Society of Chemical Industry.


Assuntos
Compostos Orgânicos Voláteis/química , Vinho/análise , China , Aromatizantes/química , Humanos , Análise Multivariada , Odorantes/análise , Análise de Componente Principal , Paladar , Fatores de Tempo
10.
J Sci Food Agric ; 99(14): 6644-6648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31325326

RESUMO

BACKGROUND: Apple juice is rich in polyphenolic compounds, especially in chlorogenic acid. A sour and bitter taste has been attributed to the compound. Chlorogenic acid in coffee powder was quickly hydrolysed by a p-coumaryl esterase of Rhizoctonia solani (RspCAE) at its optimal pH of 6.0. It was unknown, however, if RspCAE would also degrade chlorogenic acid under the strongly acidic conditions (pH 3.3) present in apple juice. RESULTS: Treatment of apple juice with RspCAE led to a chlorogenic acid degradation from 53.38 ± 0.94 mg L-1 to 21.02 ± 1.47 mg L-1 . Simultaneously, the caffeic acid content increased from 6.72 ± 0.69 mg L-1 to 19.33 ± 1.86 mg/L-1 . The aroma profile of the enzymatically treated sample and a control sample differed in only one volatile. Vitispirane had a higher flavour dilution factor in the treated juice. Sensory analysis showed no significant difference in the taste profile ( p < 0.05). CONCLUSION: These results demonstrated a high stability and substrate specificity of RspCAE. An increase in caffeic acid and a concurrent decrease in chlorogenic acid concentration may exert a beneficial effect on human health. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ácido Clorogênico/química , Esterases/química , Sucos de Frutas e Vegetais/análise , Proteínas Fúngicas/química , Malus/química , Rhizoctonia/enzimologia , Aromatizantes/química , Concentração de Íons de Hidrogênio , Hidrólise , Odorantes/análise , Especificidade por Substrato
11.
J Food Sci ; 84(8): 2261-2268, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313301

RESUMO

The consumer demand for locally grown fresh produce is continuously increasing in the United States. The high tunnel systems have been successfully utilized by small acreage growers for local production. Consumers are typically assessing appearance, freshness, flavor and aroma when purchasing produce. A common perception is that locally grown produce tastes better than nonlocal. However, there is not much evidence for supporting this claim. The objective of this study was to identify consumer acceptability and the sensory characteristics/differences of locally grown spinach in open field or in high tunnel and nonlocal commercially grown spinach. Spinach, Spinacia oleracea cv. "Corvair" was grown in open field and in high tunnel at Kansas State Univ. Olathe Horticulture Research and Extension Center (OHREC) in spring 2017 and the commercially grown spinach was purchased at a local retail store. A consumer study (n = 205) was conducted at Kansas State Univ., Olathe campus, and a descriptive sensory analysis was conducted by a highly trained descriptive analysis panel in the Center for Sensory Analysis and Consumer Behavior at Kansas State Univ., Manhattan campus, in spring 2017. The consumer test showed that high tunnel spinach scored significantly higher in overall liking (P < 0.0001), flavor liking (P < 0.0001), and texture liking (P < 0.05) when compared to open field and store purchased spinach. Descriptive analysis showed that locally grown spinach had higher intensity of attributes that indicate premium quality, such as green color and green/spinach flavors. Our results indicate that locally grown spinach was preferred from the consumers for its high organoleptic quality. PRACTICAL APPLICATION: Locally grown spinach demonstrated high intensity in a set of sensory attributes that suggest a product with premium organoleptic quality. Correspondingly to these results, consumers liked spinach produced locally in high tunnels the most. The results of this study can be used for developing marketing strategies that are aiming specifically to the consumer niche that is seeking fresh produce of high organoleptic quality.


Assuntos
Comportamento do Consumidor , Spinacia oleracea/química , Cor , Aromatizantes/química , Aromatizantes/metabolismo , Preferências Alimentares , Humanos , Kansas , Odorantes/análise , Spinacia oleracea/crescimento & desenvolvimento , Spinacia oleracea/metabolismo , Paladar
12.
Food Chem ; 298: 125060, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261004

RESUMO

Typical ketone flavours (with variations in chain length, position and number of keto group, branched chain) were selected to investigate the effect of molecule structure of ketones on their interactions with myofibrillar proteins (MPs). Results showed that 2,3-pentanedione quenched the fluorescence of MPs more effectively than 2-pentanone and 3-pentanone due to the number of keto group. There was no significant difference between 5-methyl-2-hexanone and 2-heptanone, which was attributed to their similar molecular size and polarity. The quenching effect of homologous ketone flavours increased with carbon chain growth due to the higher hydrophobic interaction. Dynamic quenching played a major role in the fluorescence quenching process of MPs by 2-pentanone, 3-pentanone, 5-methyl-2-hexanone, 2-heptanone and 2-octanone. The α-helix content decreased gradually with the increase of ketones concentration. Results of GC/MS were in accordance with the fluorescence quenching analysis generally, whereas 2,3-pentanedione and 2-nonanone exhibited some differences due to their higher steric hindrance effects.


Assuntos
Aromatizantes/química , Cetonas/química , Proteínas Musculares/química , Animais , Dicroísmo Circular , Aromatizantes/análise , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/metabolismo , Proteínas Musculares/metabolismo , Ligação Proteica , Microextração em Fase Sólida , Espectrometria de Fluorescência , Suínos
13.
Food Chem ; 298: 125062, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31280088

RESUMO

The industrial transformation of tomato (Lycopersicon esculentum Mill.) produces processed foods, such as dried tomatoes. In this study two varieties (SaAb and PerBruzzo), grown in three cropping systems (one conventional and two organic ones), were processed by two types of small-scale drying (oven or sun drying), over two years of production. The dried samples were analyzed for their non-volatile and volatile composition, relating the results with sensory analysis. The multivariate analysis performed on collected data allowed a detailed comparison of the effects of processing, year-to year variation and cropping systems. Results indicated that drying methods mainly influenced the composition and flavor profile, also affected by the production year. The cropping system significantly influenced some quality indices, such as the acid and sugar amounts, and the aldehydes, respectively higher and lower in organic samples. The comprehensive PCA analysis allowed discrimination of drying methods and, to a lesser extent, cropping systems.


Assuntos
Aromatizantes/química , Lycopersicon esculentum/química , Nariz Eletrônico , Aromatizantes/análise , Liofilização , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Lycopersicon esculentum/metabolismo , Agricultura Orgânica , Análise de Componente Principal , Estações do Ano , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
14.
Food Chem ; 297: 125018, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253265

RESUMO

Different Ohmic heating conditions (OH, 10, 100, and 1000 Hz at 25 V; 45, 60, and 80 V at 60 Hz) were assessed to manufacture whey-raspberry flavored beverages. The inhibition of α-glucosidase, α-amylase, and angiotensin-converting I enzymes, antioxidant capacity, fatty acid profile, and volatile organic compounds (VOCs) were determined. OH treated samples presented lower anthocyanins content than the conventional treatment (2.91 ±â€¯0.23 mg/g), while the mild-intermediate conditions (10,100-Hz at 25 V and 45,60-V at 60 Hz) presented the highest chemical antioxidant activity when compared to the extreme processing conditions (1000 Hz-25 V and 80 V-60 Hz). OH led to an increase of 10% in both α-glucosidase (>99%) and α-amylase (≥70%). Among the VOCs, furfural and 5-hydroxymethylfurfural, a major intermediate Maillard reaction product was found in all treatments. Overall, OH can be used in the processing of whey-flavored raspberry beverages.


Assuntos
Bebidas/análise , Aromatizantes/química , Rubus/química , Soro do Leite/química , Antocianinas/análise , Antioxidantes/química , Culinária , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucosidases/antagonistas & inibidores , Glucosidases/metabolismo , Ondas de Rádio , Temperatura Ambiente , Compostos Orgânicos Voláteis/análise , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
15.
J Agric Food Chem ; 67(28): 7926-7934, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31250635

RESUMO

Black garlic is a new garlic product produced through fermentation of fresh garlic and is very popular in Asia countries due to its health benefits. Its key aroma-active compounds were characterized by gas chromatography-olfactometry-mass spectrometry (GC-O-MS), gas chromatography-time-of-flight mass spectrometry (GC-TOFMS), and sensory evaluation. In total 52 aroma compounds were identified, and 15 of them with high flavor dilution (FD) factors based on aroma extract dilution analysis (AEDA) were selected and quantitated. Finally, 9 key aroma-active compounds, including acetic acid (sour), allyl methyl trisulfide (cooked garlic), Furaneol (caramel), diallyldisulfide (garlic), diallyltrisulfide (sulfur), (E,Z)-2,6-nonadien-1-ol (cucumber), 3-methylbutanoic acid (sweat), 5-heptyldihydro-2(3H)-furanone (apricot), and diallyl sulfide (garlic), were determined through aroma recombination and omission experiment. In addition to the sulfur-containing compounds, heterocyclic compounds were the major aroma contributors in black garlic. Sensory evaluation revealed that the flavor profile of black garlic mainly consisted of sulfur, sour, sweet, fresh, sauce, gasoline, and roasted odors.


Assuntos
Aromatizantes/química , Alho/química , Compostos Orgânicos Voláteis/química , Adulto , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Olfato , Paladar
16.
J Agric Food Chem ; 67(25): 7098-7109, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31199133

RESUMO

Wine aging bouquet is defined as a positive, complex evolution of aromas during bottle aging. The aim of this study was to look for the link between some of the vine status parameters and the development, during wine aging, of volatile compounds such as DMS, tabanones, and some wine aromatic heterocycles. The potential influence of air temperature was investigated as well as vine nitrogen and water status. Wines were obtained by microvinification from plots of Vitis vinifera L. cv. Merlot, Cabernet-Sauvignon, and Cabernet franc, over vintages from 1996 to 2007, and cellar-aged until 2014. Wine aging aromas were quantified using gas chromotography-mass spectrometry. The effects of the vintage and vine water and nitrogen status were greater than the varietal effects. The nine aroma compounds measured showed very high levels in the 2003 vintage. The results revealed a positive link between vine nitrogen status and dimethyl-sulfide and N, S, O-heterocycle levels measured in the aged wines. Levels of 4-[2-butylidene]-3,5,5-trimethyl-2-cyclohexen-1-one and 4-[( 3E)-1-butylidene]-3,5,5-trimethyl-2-cyclohexen-1-one (megastigmatrienones; tabanone) isomers increased when the vines were affected by a water deficit.


Assuntos
Aromatizantes/química , Nitrogênio/análise , Vitis/química , Compostos Orgânicos Voláteis/química , Água/análise , Vinho/análise , Irrigação Agrícola , Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Isomerismo , Nitrogênio/metabolismo , Temperatura Ambiente , Fatores de Tempo , Vitis/metabolismo , Água/metabolismo
17.
J Agric Food Chem ; 67(25): 7110-7119, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240930

RESUMO

Soft pretzels show a uniform brown crust color and elicit a characteristic aroma that is clearly different from those of other small types of bread. Data on the odorants responsible for this unique aroma are scarcely available. Application of aroma extract dilution analysis (AEDA) on an extract (distillate) obtained from the crust of freshly baked soft pretzels followed by identification experiments revealed 4-hydroxy-2,5-dimethyl-3(2 H)-furanone (4-HDF, caramel-like) and 2-acetyl-1-pyrroline (2-ACPY; roasty, popcorn-like), which had the highest flavor dilution (FD) factors among the 28 odor-active compounds identified. Quantitation of all 28 aroma compounds by stable isotope dilution assays (SIDA) and calculation of odor activity values (OAV) confirmed 2-ACPY, 4-HDF, and phenylacetic acid as key contributors to the pretzel aroma profile. Compared with other pastry crusts, in particular, the low odor activities of the Strecker aldehydes 2- and 3-methylbutanal, the lipid degradation product ( E)-2-nonenal, and the lack of pyrazines were elucidated as the main reasons for the different aroma profile of pretzel crust. An aroma recombinate, which is among the first established for the crusts of breads and pastries, clearly mimicked the overall odor of the pretzel crust, in particular when a solution in ethanol was sprayed in the ambient air.


Assuntos
Pão/análise , Aromatizantes/química , Compostos Orgânicos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Olfatometria , Olfato , Paladar
18.
Food Chem ; 293: 120-126, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151591

RESUMO

The effects of the natural ingredients Angelica sinensis (AS) and Codonopsis pilosula (CP) on the shelf life of chicken seasoning were investigated. Color differences and sensory evaluation were used to indicate sensory differences. Changes in volatiles were monitored. The rate of increase in the color value a* of the AS and CP samples was lower than that in the control. Rancid flavor appeared later in the AS and CP samples than in the control. The levels of aldehydes, ketones, and alkenes increased during storage. A kinetic model was built based on the proportion of aldehydes (main marker), to predict shelf life. The predicted shelf life at room temperature was 60 days for the control, 114 days for AS, and 89 days for CP. The shelf life of chicken seasoning could be prolonged with AS and CP. This kinetic model can be used to predict the shelf life of chicken seasoning.


Assuntos
Aromatizantes/química , Aldeídos/química , Aldeídos/metabolismo , Alcenos/química , Alcenos/metabolismo , Angelica sinensis/química , Angelica sinensis/metabolismo , Animais , Galinhas , Codonopsis/química , Codonopsis/metabolismo , Cor , Aromatizantes/metabolismo , Armazenamento de Alimentos , Cetonas/química , Cetonas/metabolismo , Cinética , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
19.
J Sci Food Agric ; 99(12): 5577-5585, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150111

RESUMO

BACKGROUND: One of the most important species used to ferment Chinese turbid rice wine (CTRW) at an industrial-scale level is Rhizopus oryzae, although the flavor of CTRW fermented by pure R. oryzae is inferior to that of traditional CTRW. RESULTS: Mucor indicus was used as a cooperative species to improve the flavor of CTRW presented by R. oryzae. The flavor compounds in different fermentation stages were determined by headspace solid-phase microextraction-gas chromatography-mass spectrometry and high-performance liquid chromatography. It was noted that the M. indicus and R. oryzae co-culture changed the profiles of flavor compounds in CTRW, including esters, higher alcohols, amino acids and organic acids, and also significantly enhanced the concentration of sweet amino acids, fruity and floral esters, and higher alcohols. Sensory evaluation demonstrated that the CTRW fermented by M. indicus and R. oryzae had a more intense aroma, harmonious taste, continuation and full body mouth-feel because of more abundant flavor compounds. CONCLUSION: Mucor indicus is a promising species for co-culture with R. oryzae to improve the flavor of CTRW. © 2019 Society of Chemical Industry.


Assuntos
Aromatizantes/química , Mucor/metabolismo , Oryza/microbiologia , Rhizopus/metabolismo , Vinho/análise , China , Técnicas de Cocultura , Fermentação , Aromatizantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Mucor/crescimento & desenvolvimento , Odorantes/análise , Oryza/química , Rhizopus/crescimento & desenvolvimento , Microextração em Fase Sólida , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Vinho/microbiologia
20.
Food Chem ; 295: 569-578, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174797

RESUMO

Fish scales are usually discarded or used to produce fish meal, etc. In order to enhance their utility, we produced the gelatin hydrolysates from fish scales (FSGH) and they were heated with glucose, xylose, and ribose to prepare sugar-FSGH Maillard reaction products (MRPs). The antioxidant capacity and sensory property of MRPs were evaluated. The results showed that ribose-FSGH MRPs exhibited higher antioxidant capacity than glucose- and xylose-FSGH MRPs. After simulated gastrointestinal digestion, the DPPH and ABTS scavenging activity of ribose-FSGH MRPs were 25.32 µM and 193.37 µM Trolox equivalent/g sample, respectively, and the reducing power was 0.509. Flavor compounds (such as butanal, benzaldehyde, 2-methyl-3-furanthiol, and maltol) of ribose-FSGH MRPs were produced in abundance after 5 h of heating and ribose-FSGH MRPs exhibited flavor enhanced effect on caramel-like and mouthfulness sensory attributes. These results suggest that ribose-FSGH MRPs can be potentially used as food antioxidants.


Assuntos
Antioxidantes/química , Carpas/metabolismo , Gelatina/metabolismo , Produtos Finais de Glicação Avançada/química , Compostos Orgânicos Voláteis/análise , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Aromatizantes/química , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Alimentos Marinhos/análise , Temperatura Ambiente
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