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1.
Food Res Int ; 186: 114401, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729704

RESUMO

Fuzhuan brick tea (FBT) fungal fermentation is a key factor in achieving its unique dark color, aroma, and taste. Therefore, it is essential to develop a rapid and reliable method that could assess its quality during FBT fermentation process. This study focused on using electronic nose (e-nose) and spectroscopy combination with sensory evaluations and physicochemical measurements for building machine learning (ML) models of FBT. The results showed that the fused data achieved 100 % accuracy in classifying the FBT fermentation process. The SPA-MLR method was the best prediction model for FBT quality (R2 = 0.95, RMSEP = 0.07, RPD = 4.23), and the fermentation process was visualized. Where, it was effectively detecting the degree of fermentation relationship with the quality characteristics. In conclusion, the current study's novelty comes from the established real-time method that could sensitively detect the unique post-fermentation quality components based on the integration of spectral, and e-nose and ML approaches.


Assuntos
Nariz Eletrônico , Fermentação , Espectroscopia de Luz Próxima ao Infravermelho , Paladar , Chá , Chá/química , Chá/microbiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Odorantes/análise , Quimiometria/métodos , Humanos , Fungos/metabolismo , Aprendizado de Máquina , Compostos Orgânicos Voláteis/análise
2.
Food Res Int ; 187: 114330, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763633

RESUMO

Processing technology plays a crucial role in the formation of tea aroma. The dynamic variations in volatile metabolites across different processing stages of fresh scent green tea (FSGT) were meticulously tracked utilizing advanced analytical techniques such as GC-E-Nose, GC-MS, and GC × GC-TOFMS. A total of 244 volatile metabolites were identified by GC-MS and GC × GC-TOFMS, among which 37 volatile compounds were concurrently detected by both methods. Spreading and fixation stages were deemed as pivotal processes for shaping the volatile profiles in FSGT. Notably, linalool, heptanal, 2-pentylfuran, nonanal, ß-myrcene, hexanal, 2-heptanone, pentanal, 1-octen-3-ol, and 1-octanol were highlighted as primary contributors to the aroma profiles of FSGT by combining odor activity value assessment. Furthermore, lipid degradation and glycoside hydrolysis were the main pathways for aroma formation of FSGT. The results not only elucidate the intricate variations in volatile metabolites but also offer valuable insights into enhancing the processing techniques for improved aroma quality of green tea.


Assuntos
Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Chá , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Chá/química , Manipulação de Alimentos/métodos , Nariz Eletrônico , Aldeídos/análise , Aldeídos/metabolismo , Monoterpenos Acíclicos/metabolismo , Monoterpenos Acíclicos/análise , Camellia sinensis/química , Camellia sinensis/metabolismo , Cetonas/análise , Cetonas/metabolismo , Octanóis
3.
Food Res Int ; 187: 114353, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763640

RESUMO

The food industry has grown with the demands for new products and their authentication, which has not been accompanied by the area of analysis and quality control, thus requiring novel process analytical technologies for food processes. An electronic tongue (e-tongue) is a multisensor system that can characterize complex liquids in a fast and simple way. Here, we tested the efficacy of an impedimetric microfluidic e-tongue setup - comprised by four interdigitated electrodes (IDE) on a printed circuit board (PCB), with four pairs of digits each, being one bare sensor and three coated with different ultrathin nanostructured films with different electrical properties - in the analysis of fresh and industrialized coconut water. Principal Component Analysis (PCA) was applied to observe sample differences, and Partial Least Squares Regression (PLSR) was used to predict sample physicochemical parameters. Linear Discriminant Analysis (LDA) and Partial Least Square - Discriminant Analysis (PLS-DA) were compared to classify samples based on data from the e-tongue device. Results indicate the potential application of the microfluidic e-tongue in the identification of coconut water composition and determination of physicochemical attributes, allowing for classification of samples according to soluble solid content (SSC) and total titratable acidity (TTA) with over 90% accuracy. It was also demonstrated that the microfluidic setup has potential application in the food industry for quality assessment of complex liquid samples.


Assuntos
Cocos , Espectroscopia Dielétrica , Análise de Componente Principal , Cocos/química , Análise dos Mínimos Quadrados , Espectroscopia Dielétrica/métodos , Análise Discriminante , Água/química , Análise de Alimentos/métodos , Microfluídica/métodos , Microfluídica/instrumentação , Nariz Eletrônico
4.
Respir Res ; 25(1): 203, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730430

RESUMO

BACKGROUND: Although electronic nose (eNose) has been intensively investigated for diagnosing lung cancer, cross-site validation remains a major obstacle to be overcome and no studies have yet been performed. METHODS: Patients with lung cancer, as well as healthy control and diseased control groups, were prospectively recruited from two referral centers between 2019 and 2022. Deep learning models for detecting lung cancer with eNose breathprint were developed using training cohort from one site and then tested on cohort from the other site. Semi-Supervised Domain-Generalized (Semi-DG) Augmentation (SDA) and Noise-Shift Augmentation (NSA) methods with or without fine-tuning was applied to improve performance. RESULTS: In this study, 231 participants were enrolled, comprising a training/validation cohort of 168 individuals (90 with lung cancer, 16 healthy controls, and 62 diseased controls) and a test cohort of 63 individuals (28 with lung cancer, 10 healthy controls, and 25 diseased controls). The model has satisfactory results in the validation cohort from the same hospital while directly applying the trained model to the test cohort yielded suboptimal results (AUC, 0.61, 95% CI: 0.47─0.76). The performance improved after applying data augmentation methods in the training cohort (SDA, AUC: 0.89 [0.81─0.97]; NSA, AUC:0.90 [0.89─1.00]). Additionally, after applying fine-tuning methods, the performance further improved (SDA plus fine-tuning, AUC:0.95 [0.89─1.00]; NSA plus fine-tuning, AUC:0.95 [0.90─1.00]). CONCLUSION: Our study revealed that deep learning models developed for eNose breathprint can achieve cross-site validation with data augmentation and fine-tuning. Accordingly, eNose breathprints emerge as a convenient, non-invasive, and potentially generalizable solution for lung cancer detection. CLINICAL TRIAL REGISTRATION: This study is not a clinical trial and was therefore not registered.


Assuntos
Aprendizado Profundo , Nariz Eletrônico , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Feminino , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Reprodutibilidade dos Testes , Testes Respiratórios/métodos , Adulto
5.
Food Res Int ; 183: 114180, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760124

RESUMO

Platostoma palustre (Mesona chinensis Benth or Hsian-tsao, also known as "Xiancao" in China), is an edible and medicinal plant native to India, Myanmar, and Indo-China. It is the main ingredient in the popular desserts Hsian-tsao tea, herbal jelly, and sweet herbal jelly soup. P. palustre is found abundantly in nutrient-rich substances and possesses unique aroma compounds. Variations in the contents of volatile compounds among different germplasms significantly affect the quality and flavor of P. palustre, causing contradiction in demand. This study investigates the variation in the volatile compound profiles of distinct ploidy germplasms of P. palustre by utilising headspace gas chromatography-mass spectrometry (HS-GC-MS) and an electronic nose (e-nose). The results showed significant differences in the aroma characteristics of stem and leaf samples in diverse P. palustre germplasms. A total of sixty-seven volatile compounds have been identified and divided into ten classes. Six volatile compounds (caryophyllene, α-bisabolol, benzaldehyde, ß-selinene, ß-elemene and acetic acid) were screened as potential marker volatile compounds to discriminate stems and leaves of P. palustre. In this study, leaves of P. palustre showed one odor pattern and stems showed two odor patterns under the influence of α-bisabolol, acetic acid, and butyrolactone. In addition, a correlation analysis was conducted on the main volatile compounds identified by HS-GC-MS and e-nose. This analysis provided additional insight into the variations among samples resulting from diverse germplasms. The present study provides a valuable volatilome, and flavor, and quality evaluation for P. palustre, as well as new insights and scientific basis for the development and use of P. palustre germplasm resources.


Assuntos
Nariz Eletrônico , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Folhas de Planta/química , Paladar , Caules de Planta/química
6.
Food Res Int ; 183: 114211, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760139

RESUMO

The wheat grains that are cultivated in saline-alkali soil exhibit a richer "wheat aroma" compared to their counterparts. This study characterized the composition and content of volatiles in five wheat kernel varieties, harvested from two fields with varying pH levels and total salt content in the soil. The wheat grown in soil with high pH and total salt content had significantly lower levels (p < 0.05) of ethyl 3-methylbutanoate and 1-octen-3-one and significantly higher levels (p < 0.05) of 1-butanol and 1-octen-3-ol. Among all factors, plant site contributed the highest F-value contribution rate (more than 77 %) for these four volatile compounds. Six e-nose sensors responsive to these four compounds exhibited consistent trends. Therefore, the lower of ethyl 3-methylbutanoate and 1-octen-3-one, the higher of 1-butanol and 1-octen-3-ol in wheat, grown on saline-alkali soil, served as characteristic markers for "wheat aroma".


Assuntos
Odorantes , Solo , Triticum , Compostos Orgânicos Voláteis , Triticum/química , Compostos Orgânicos Voláteis/análise , Solo/química , Odorantes/análise , Concentração de Íons de Hidrogênio , Álcalis/química , Cromatografia Gasosa-Espectrometria de Massas , Nariz Eletrônico
7.
J Chromatogr A ; 1725: 464931, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38703457

RESUMO

Atractylodis rhizoma is a common bulk medicinal material with multiple species. Although different varieties of atractylodis rhizoma exhibit variations in their chemical constituents and pharmacological activities, they have not been adequately distinguished due to their similar morphological features. Hence, the purpose of this research is to analyze and characterize the volatile organic compounds (VOCs) in samples of atractylodis rhizoma using multiple techniques and to identify the key differential VOCs among different varieties of atractylodis rhizoma for effective discrimination. The identification of VOCs was carried out using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS), resulting in the identification of 60 and 53 VOCs, respectively. The orthogonal partial least squares discriminant analysis (OPLS-DA) model was employed to screen potential biomarkers and based on the variable importance in projection (VIP ≥ 1.2), 24 VOCs were identified as critical differential compounds. Random forest (RF), K-nearest neighbor (KNN) and back propagation neural network based on genetic algorithm (GA-BPNN) models based on potential volatile markers realized the greater than 90 % discriminant accuracies, which indicates that the obtained key differential VOCs are reliable. At the same time, the aroma characteristics of atractylodis rhizoma were also analyzed by ultra-fast gas chromatography electronic nose (Ultra-fast GC E-nose). This study indicated that the integration of HS-SPME-GC-MS, HS-GC-IMS and ultra-fast GC E-nose with chemometrics can comprehensively reflect the differences of VOCs in atractylodis rhizoma samples from different varieties, which will be a prospective tool for variety discrimination of atractylodis rhizoma.


Assuntos
Atractylodes , Nariz Eletrônico , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Atractylodes/química , Espectrometria de Mobilidade Iônica/métodos , Rizoma/química , Análise Discriminante
8.
Sensors (Basel) ; 24(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38610504

RESUMO

Electronic nose devices stand out as pioneering innovations in contemporary technological research, addressing the arduous challenge of replicating the complex sense of smell found in humans. Currently, sensor instruments find application in a variety of fields, including environmental, (bio)medical, food, pharmaceutical, and materials production. Particularly the latter, has seen a significant increase in the adoption of technological tools to assess food quality, gradually supplanting human panelists and thus reshaping the entire quality control paradigm in the sector. This process is happening even more rapidly in the world of wine, where olfactory sensory analysis has always played a central role in attributing certain qualities to a wine. In this review, conducted using sources such as PubMed, Science Direct, and Web of Science, we examined papers published between January 2015 and January 2024. The aim was to explore prevailing trends in the use of human panels and sensory tools (such as the E-nose) in the wine industry. The focus was on the evaluation of wine quality attributes by paying specific attention to geographical origin, sensory defects, and monitoring of production trends. Analyzed results show that the application of E-nose-type sensors performs satisfactorily in that trajectory. Nevertheless, the integration of this type of analysis with more classical methods, such as the trained sensory panel test and with the application of destructive instrument volatile compound (VOC) detection (e.g., gas chromatography), still seems necessary to better explore and investigate the aromatic characteristics of wines.


Assuntos
Nariz Eletrônico , Vinho , Humanos , Controle de Qualidade , Qualidade dos Alimentos , Geografia
9.
Biosens Bioelectron ; 256: 116260, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613935

RESUMO

Various bioelectronic noses have been recently developed for mimicking human olfactory systems. However, achieving direct monitoring of gas-phase molecules remains a challenge for the development of bioelectronic noses due to the instability of receptor and the limitations of its surrounding microenvironment. Here, we report a MXene/hydrogel-based bioelectronic nose for the sensitive detection of liquid and gaseous hexanal, a signature odorant from spoiled food. In this study, a conducting MXene/hydrogel structure was formed on a sensor via physical adsorption. Then, canine olfactory receptor 5269-embedded nanodiscs (cfOR5269NDs) which could selectively recognize hexanal molecules were embedded in the three-dimensional (3D) MXene/hydrogel structures using glutaraldehyde as a linker. Our MXene/hydrogel-based bioelectronic nose exhibited a high selectivity and sensitivity for monitoring hexanal in both liquid and gas phases. The bioelectronic noses could sensitively detect liquid and gaseous hexanal down to 10-18 M and 6.9 ppm, and they had wide detection ranges of 10-18 - 10-6 M and 6.9-32.9 ppm, respectively. Moreover, our bioelectronic nose allowed us to monitor hexanal levels in fish and milk. In this respect, our MXene/hydrogel-based bioelectronic nose could be a practical strategy for versatile applications such as food spoilage assessments in both liquid and gaseous systems.


Assuntos
Técnicas Biossensoriais , Nariz Eletrônico , Técnicas Biossensoriais/métodos , Animais , Gases/química , Gases/análise , Aldeídos/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Cães , Receptores Odorantes/química , Humanos , Leite/microbiologia , Leite/química , Desenho de Equipamento , Odorantes/análise
10.
Nanoscale ; 16(19): 9259-9283, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38680123

RESUMO

An electronic nose (E-nose) is a technology fundamentally inspired by the human nose, designed to detect, recognize, and differentiate specific odors or volatile components in complex and chaotic environments. Comprising an array of sensors with meticulously designed nanostructured architectures, E-noses translate the chemical information captured by these sensors into useful metrics using complex pattern recognition algorithms. E-noses can significantly enhance the quality of life by offering preventive point-of-care devices for medical diagnostics through breath analysis, and by monitoring and tracking hazardous and toxic gases in the environment. They are increasingly being used in defense and surveillance, medical diagnostics, agriculture, environmental monitoring, and product validation and authentication. The major challenge in developing a reliable E-nose involves miniaturization and low power consumption. Various sensing materials are employed to address these issues. This review presents the key advancements over the last decade in E-nose technology, specifically focusing on chemiresistive metal oxide sensing materials. It discusses their sensing mechanisms, integration into portable E-noses, and various data analysis techniques. Additionally, we review the primary metal oxide-based E-noses for disease detection through breath analysis. Finally, we address the major challenges and issues in developing and implementing a portable metal oxide-based E-nose.


Assuntos
Nariz Eletrônico , Metais , Óxidos , Humanos , Óxidos/química , Metais/química , Testes Respiratórios , Nanoestruturas/química
11.
Food Res Int ; 185: 114277, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658069

RESUMO

For some food applications, it is desirable to control the flavor release profiles of volatile flavor compounds. In this study, the effects of crosslinking method and protein composition on the flavor release properties of emulsion-filled protein hydrogels were explored, using peppermint essential oil as a model volatile compound. Emulsion-filled protein gels with different properties were prepared using different crosslinking methods and gelatin concentrations. Flavor release from the emulsion gels was then monitored using an electronic nose, gas chromatography-mass spectrometry (GC-MS), and sensory evaluation. Enzyme-crosslinked gels had greater hardness and storage modulus than heat-crosslinked ones. The hardness and storage modulus of the gels increased with increasing gelatin concentration. For similar gel compositions, flavor release and sensory perception were faster from the heat-crosslinked gels than the enzyme-crosslinked ones. For the same crosslinking method, flavor release and perception decreased with increasing gelatin concentration, which was attributed to retardation of flavor diffusion through the hydrogel matrix. Overall, this study shows that the release of hydrophobic aromatic substances can be modulated by controlling the composition and crosslinking of protein hydrogels, which may be useful for certain food applications.


Assuntos
Emulsões , Aromatizantes , Cromatografia Gasosa-Espectrometria de Massas , Mentha piperita , Óleos de Plantas , Mentha piperita/química , Emulsões/química , Humanos , Óleos de Plantas/química , Aromatizantes/química , Gelatina/química , Reagentes de Ligações Cruzadas/química , Paladar , Hidrogéis/química , Nariz Eletrônico , Masculino , Feminino , Adulto
12.
Zhongguo Zhong Yao Za Zhi ; 49(4): 924-931, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621899

RESUMO

Odor is one of the important indicators evaluating the quality of traditional Chinese medicines. Research data has shown that there are increasing methods available for evaluating the odors of traditional Chinese medicines. Compared with conventional odor sensing techniques, electronic noses stand out for their convenience, high speed, and objectivity. The progress in the pharmaceutical technology of traditional Chinese medicines has provided new formulas and dosage forms for the innovative development in this field. The electronic nose with versatility can be customized to be equipped with a variety of cross-sensors, which can well satisfy the needs of the traditional Chinese medicine preparation technology. This study summarizes the characteristics, application status, and representative products of the current electronic nose, and analyzes the application and feasibility of electronic nose in the production of traditional Chinese medicine preparations based on the current status of odor evaluation. This review is expected to provide new methods, techno-logies, and ideas for electronic nose to play its unique role in the whole-process quality control and pharmaceutical process of traditional Chinese medicine preparations.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Nariz Eletrônico , Controle de Qualidade , Eletrônica
13.
Talanta ; 274: 126006, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569371

RESUMO

This study proposes an efficient method for monitoring the submerged fermentation process of Tremella fuciformis (T. fuciformis) by integrating electronic nose (e-nose), electronic tongue (e-tongue), and colorimeter sensors using a data fusion strategy. Chemometrics was employed to establish qualitative identification and quantitative prediction models. The Pearson correlation analysis was applied to extract features from the e-nose and tongue sensor arrays. The optimal sensor arrays for monitoring the submerged fermentation process of T. fuciformis were obtained, and four different data fusion methods were developed by incorporating the colorimeter data features. To achieve qualitative identification, the physicochemical data and principal component analysis (PCA) results were utilized to determine three stages of the fermentation process. The fusion signal based on full features proved to be the optimal data fusion method, exhibiting the highest accuracy across different models. Notably, random forest (RF) was shown to be the most accurate pattern recognition method in this paper. For quantitative prediction, partial least squares regression (PLSR) and support vector regression (SVR) were employed to predict the sugar content and dry cell weight during fermentation. The best respective predictive R2 values for reducing sugar, tremella polysaccharide and dry cell weight were found to be 0.965, 0.988, and 0.970. Furthermore, due to its ability to capture nonlinear data relationships, SVR had superior performance in prediction modeling than PLSR. The results demonstrated that the combination of electronic sensor fusion signals and chemometrics provided a promising method for effectively monitoring T. fuciformis fermentation.


Assuntos
Basidiomycota , Colorimetria , Nariz Eletrônico , Fermentação , Basidiomycota/metabolismo , Colorimetria/métodos , Quimiometria/métodos , Análise de Componente Principal , Análise dos Mínimos Quadrados
14.
Biosensors (Basel) ; 14(4)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38667183

RESUMO

As technology advances, electronic tongues and noses are becoming increasingly important in various industries. These devices can accurately detect and identify different substances and gases based on their chemical composition. This can be incredibly useful in fields such as environmental monitoring and industrial food applications, where the quality and safety of products or ecosystems should be ensured through a precise analysis. Traditionally, this task is performed by an expert panel or by using laboratory tests but sometimes becomes a bottleneck because of time and other human factors that can be solved with technologies such as the provided by electronic tongue and nose devices. Additionally, these devices can be used in medical diagnosis, quality monitoring, and even in the automotive industry to detect gas leaks. The possibilities are endless, and as these technologies continue to improve, they will undoubtedly play an increasingly important role in improving our lives and ensuring our safety. Because of the multiple applications and developments in this field in the last years, this work will present an overview of the electronic tongues and noses from the point of view of the approaches developed and the methodologies used in the data analysis and steps to this aim. In the same manner, this work shows some of the applications that can be found in the use of these devices and ends with some conclusions about the current state of these technologies.


Assuntos
Nariz Eletrônico , Técnicas Biossensoriais
15.
Molecules ; 29(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611821

RESUMO

This study aimed to investigate the volatile flavor compounds and tastes of six kinds of sauced pork from the southwest and eastern coastal areas of China using gas chromatography-ion mobility spectroscopy (GC-IMS) combined with an electronic nose (E-nose) and electronic tongue (E-tongue). The results showed that the combined use of the E-nose and E-tongue could effectively identify different kinds of sauced pork. A total of 52 volatile flavor compounds were identified, with aldehydes being the main flavor compounds in sauced pork. The relative odor activity value (ROAV) showed that seven key volatile compounds, including 2-methylbutanal, 2-ethyl-3, 5-dimethylpyrazine, 3-octanone, ethyl 3-methylbutanoate, dimethyl disulfide, 2,3-butanedione, and heptane, contributed the most to the flavor of sauced pork (ROAV ≥1). Multivariate data analysis showed that 13 volatile compounds with the variable importance in projection (VIP) values > 1 could be used as flavor markers to distinguish six kinds of sauced pork. Pearson correlation analysis revealed a significant link between the E-nose sensor and alcohols, aldehydes, terpenes, esters, and hetero-cycle compounds. The results of the current study provide insights into the volatile flavor compounds and tastes of sauced pork. Additionally, intelligent sensory technologies can be a promising tool for discriminating different types of sauced pork.


Assuntos
Carne de Porco , Carne Vermelha , Suínos , Animais , Nariz Eletrônico , China , Análise Espectral , Aldeídos , Cromatografia Gasosa
16.
Sensors (Basel) ; 24(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38676183

RESUMO

The electronic nose is a non-invasive technology suitable for the analysis of edible oils. One of the practical applications in the olive oil industry is the classification of virgin oils based on their sensory characteristics. Notwithstanding that this technology, at this stage, cannot realistically replace the currently used methods, it is fruitful for a preliminary analysis of the oil quality. This work makes use of this technology to develop a methodology for the detection of the threshold by which an extra-virgin olive oil (EVOO) drops into the virgin olive oil (VOO) category. With this aim, two features were studied: the level of fruitiness level and the type of defect. The results showed a greater influence of the level of fruitiness than the type of defect in the determination of the detection threshold. Furthermore, three of the sensors (S2, S7 and S9) of the commercial e-nose PEN3 were identified as the most discriminating in the classification between EVOO and VOO oils.


Assuntos
Nariz Eletrônico , Azeite de Oliva , Azeite de Oliva/química , Frutas/química
17.
Prostate ; 84(8): 756-762, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38497426

RESUMO

BACKGROUND: Many diseases leave behind specific metabolites which can be detected from breath and urine as volatile organic compounds (VOC). Our group previously described VOC-based methods for the detection of bladder cancer and urinary tract infections. This study investigated whether prostate cancer can be diagnosed from VOCs in urine headspace. METHODS: For this pilot study, mid-stream urine samples were collected from 56 patients with histologically confirmed prostate cancer. A control group was formed with 53 healthy male volunteers matched for age who had recently undergone a negative screening by prostate-specific antigen (PSA) and digital rectal exam. Headspace measurements were performed with the electronic nose Cyranose 320TM. Statistical comparison was performed using principal component analysis, calculating Mahalanobis distance, and linear discriminant analysis. Further measurements were carried out with ion mobility spectrometry (IMS) to compare detection accuracy and to identify potential individual analytes. Bonferroni correction was applied for multiple testing. RESULTS: The electronic nose yielded a sensitivity of 77% and specificity of 62%. Mahalanobis distance was 0.964, which is indicative of limited group separation. IMS identified a total of 38 individual analytical peaks, two of which showed significant differences between groups (p < 0.05). To discriminate between tumor and controls, a decision tree with nine steps was generated. This model led to a sensitivity of 98% and specificity of 100%. CONCLUSIONS: VOC-based detection of prostate cancer seems feasible in principle. While the first results with an electronic nose show some limitations, the approach can compete with other urine-based marker systems. However, it seems less reliable than PSA testing. IMS is more accurate than the electronic nose with promising sensitivity and specificity, which warrants further research. The individual relevant metabolites identified by IMS should further be characterized using gas chromatography/mass spectrometry to facilitate potential targeted rapid testing.


Assuntos
Nariz Eletrônico , Espectrometria de Mobilidade Iônica , Neoplasias da Próstata , Compostos Orgânicos Voláteis , Humanos , Masculino , Compostos Orgânicos Voláteis/urina , Compostos Orgânicos Voláteis/análise , Neoplasias da Próstata/urina , Neoplasias da Próstata/diagnóstico , Espectrometria de Mobilidade Iônica/métodos , Idoso , Pessoa de Meia-Idade , Projetos Piloto , Sensibilidade e Especificidade , Idoso de 80 Anos ou mais
18.
Food Chem ; 447: 138915, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38452539

RESUMO

Peanuts, sourced from various regions, exhibit noticeable differences in quality owing to the impact of their natural environments. This study proposes a fast and nondestructive detection method to identify peanut quality by combining an electronic nose system with a hyperspectral system. First, the electronic nose and hyperspectral systems are used to gather gas and spectral information from peanuts. Second, a module for extracting gas and spectral information is designed, combining the lightweight multi-head transposed attention mechanism (LMTA) and convolutional computation. The fusion of gas and spectral information is achieved through matrix combination and lightweight convolution. A hybrid neural network, named UnitFormer, is designed based on the information extraction and fusion processes. UnitFormer demonstrates an accuracy of 99.06 %, a precision of 99.12 %, and a recall of 99.05 %. In conclusion, UnitFormer effectively distinguishes quality differences among peanuts from various regions, offering an effective technological solution for quality supervision in the food market.


Assuntos
Arachis , Nariz Eletrônico , Meio Ambiente , Alimentos , Redes Neurais de Computação
19.
Food Res Int ; 181: 114078, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448095

RESUMO

The effects of α-amylase on of flavor perception were investigated via spectrum analysis, electronic tongue, on-line mass spectrometry, and molecular docking. Aroma release results showed that α-amylase exhibited variable release patterns of different aroma compounds. Electronic tongue analysis showed that the perception of bitterness, sweetness, sour, and saltiness was subtly increased and that of umami was significantly increased (p < 0.01) along with the increasing enzyme activity of α-amylase. Ultraviolet absorption and fluorescence spectroscopy analyses showed that static quenching occurred between α-amylase and eight flavor compounds and their interaction effects were spontaneous. One binding pocket was confirmed between the α-amylase and flavor compounds, and molecular docking simulation results showed that the hydrogen, electrostatic, and hydrophobic bonds were the main force interactions. The TYP82, TRP83, LEU173, HIS80, HIS122, ASP297, ASP206, and ARG344 were the key α-amylase amino acid residues that interacted with the eight flavor compounds.


Assuntos
Prótons , alfa-Amilases , Simulação de Acoplamento Molecular , Nariz Eletrônico , Espectrometria de Massas , Aminoácidos , Percepção
20.
J Food Sci ; 89(5): 3006-3018, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38532705

RESUMO

Wine faults threaten brand recognition and consumer brand loyalty. The objective of this study was to compare the acuteness of e-tongue and human sensory evaluation of wine fault development in Riesling wine over 42 days of storage. Riesling wines uninoculated (control) or inoculated with 104 CFU/mL cultures of Wickerhamomyces anomalus, Acetobacter aceti, Lactobacillus brevis, or Pediococcus parvulus were assessed every 7 days with the e-tongue and a rate-all-that-apply (RATA) sensory panel. After 7 days of storage, the e-tongue detected differences in all four wine spoilage microorganism treatments, compared to control wine, with discrimination indices over 86%. The RATA sensory panel detected significant differences beginning on day 35 of storage, 28 days after the e-tongue detected differences. This study showed that the e-tongue was more sensitive than the human panel as a detection tool, without sensory fatigue. PRACTICAL APPLICATION: This research is useful for winemakers seeking additional instrumental methods in the early detection of wine faults. Given the results of this study, the e-tongue can be a useful tool for detecting early chemical changes in white wines that have undergone microbial spoilage, providing winemakers with time to mitigate faults before they surpass sensory thresholds.


Assuntos
Paladar , Vinho , Vinho/análise , Vinho/microbiologia , Humanos , Nariz Eletrônico , Odorantes/análise , Adulto , Microbiologia de Alimentos/métodos , Feminino , Masculino , Armazenamento de Alimentos/métodos
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