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1.
J Food Sci ; 88(4): 1580-1594, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36871163

RESUMO

Sugar beet leaves can be a viable and economically interesting source of high-quality protein for the food industry. We investigated how storage conditions and leaf wounding at harvest affect the content and quality of the soluble protein. After collection, leaves were either stored intact or shredded to mimic wounding induced by commercial leaf harvesters. Leaf material was stored in small volumes at different temperatures to assess leaf physiology or in larger volumes to assess temperature development at different locations in the bins. Protein degradation was more pronounced at higher storage temperatures. Wounding accelerated the degradation of soluble protein at all temperatures. Both wounding and storage at higher temperatures greatly stimulated respiration activity and heat production. At temperatures below 5°C, ribulose-1,5-biphosphate carboxylase oxygenase (RuBisCO) in intact leaves was preserved for up to 3 weeks. At temperatures of 30-40°C, RuBisCO degradation occurred within 48 h. Degradation was more pronounced in shredded leaves. In 0.8-m3 storage bins at ambient temperature, core temperatures rapidly increased, up to 25°C in intact leaves and up to 45°C in shredded leaves within 2-3 days. Immediate storage at 5°C greatly suppressed the temperature increase in intact but not in shredded leaves. The indirect effect of excessive wounding, that is, heat production, is discussed as the pivotal factor responsible for increased degradation of protein. For optimal retention of soluble protein levels and quality in harvested sugar beet leaves, it is advised to minimize wounding and to store the material at temperatures around -5°C. PRACTICAL APPLICATION: To preserve the soluble protein content and quality for at least 3 weeks, sugar beet leaves should be harvested with minimal wounding and stored at temperatures between 1 and 5°C. When aiming to store minimally wounded leaves in larger volumes, it must be ensured that the product temperature in the core of the biomass meets the temperature criterium or the cooling strategy must be adjusted. The principles of minimal wounding and low temperature storage are transferable to other leafy crops that are harvested for food protein.


Assuntos
Beta vulgaris , Ribulose-Bifosfato Carboxilase/metabolismo , Temperatura , Folhas de Planta/metabolismo , Açúcares
2.
Sci Rep ; 11(1): 23109, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848748

RESUMO

Tomato is an important commercial product which is perishable by nature and highly susceptible to fungal incidence once it is harvested. Not all tomatoes are equally vulnerable to pathogenic fungi, and an early detection of the vulnerable ones can help in taking timely preventive actions, ranging from isolating tomato batches to adjusting storage conditions, but also in making right business decisions like dynamic pricing based on quality or better shelf life estimate. More importantly, early detection of vulnerable produce can help in taking timely actions to minimize potential post-harvest losses. This paper investigates Near-infrared (NIR) hyperspectral imaging (1000-1700 nm) and machine learning to build models to automatically predict the susceptibility of sepals of recently harvested tomatoes to future fungal infections. Hyperspectral images of newly harvested tomatoes (cultivar Brioso) from 5 different growers were acquired before the onset of any visible fungal infection. After imaging, the tomatoes were placed under controlled conditions suited for fungal germination and growth for a 4-day period, and then imaged using normal color cameras. All sepals in the color images were ranked for fungal severity using crowdsourcing, and the final severity of each sepal was fused using principal component analysis. A novel hyperspectral data processing pipeline is presented which was used to automatically segment the tomato sepals from spectral images with multiple tomatoes connected via a truss. The key modelling question addressed in this research is whether there is a correlation between the hyperspectral data captured at harvest and the fungal infection observed 4 days later. Using 10-fold and group k-fold cross-validation, XG-Boost and Random Forest based regression models were trained on the features derived from the hyperspectral data corresponding to each sepal in the training set and tested on hold out test set. The best model found a Pearson correlation of 0.837, showing that there is strong linear correlation between the NIR spectra and the future fungal severity of the sepal. The sepal specific predictions were aggregated to predict the susceptibility of individual tomatoes, and a correlation of 0.92 was found. Besides modelling, focus is also on model interpretation, particularly to understand which spectral features are most relevant to model prediction. Two approaches to model interpretation were explored, feature importance and SHAP (SHapley Additive exPlanations), resulting in similar conclusions that the NIR range between 1390-1420 nm contributes most to the model's final decision.


Assuntos
Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Solanum lycopersicum/microbiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Calibragem , Produtos Agrícolas , Aprendizado Profundo , Frutas/microbiologia , Solanum lycopersicum/genética , Aprendizado de Máquina , Microbiologia , Reconhecimento Automatizado de Padrão , Doenças das Plantas/prevenção & controle , Análise de Componente Principal , Reprodutibilidade dos Testes , Software
3.
Clin Nutr ; 36(6): 1642-1648, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27836309

RESUMO

BACKGROUND & AIMS: Taste and smell changes due to chemotherapy may contribute to the high prevalence of overweight in testicular cancer patients (TCPs). This study investigates the taste and smell function, dietary intake, food preference, and body composition in TCPs before, during, and up to 1 year after cisplatin-based chemotherapy. METHODS: Twenty-one consecutive TCPs participated. At baseline TCPs were compared to healthy controls (N = 48). Taste strips and 'Sniffin' Sticks' were used to determine psychophysical taste and smell function. Subjective taste, smell, appetite, and hunger were assessed using a questionnaire. Dietary intake was analyzed using a food frequency questionnaire. Food preference was assessed using food pictures varying in taste (sweet/savoury) and fat or protein content. A Dual-Energy X-ray Absorptiometry (DEXA) scan was performed to measure whole body composition. RESULTS: Compared to controls, TCPs had a lower smell threshold (P = 0.045) and lower preference for high fat sweet foods at baseline (P = 0.024). Over time, intra-individual psychophysical taste and smell function was highly variable. The salty taste threshold increased at completion of chemotherapy compared to baseline (P = 0.006). A transient decrease of subjective taste, appetite, and hunger feelings was observed per chemotherapy cycle. The percentage of fat mass increased during chemotherapy compared to baseline, while the lean mass and bone density decreased (P < 0.05). CONCLUSIONS: Coping strategies regarding subjective taste impairment should especially be provided during the first week of each chemotherapy cycle. Since the body composition of TCPs already had changed at completion of chemotherapy, intervention strategies to limit the impact of cardiovascular risk factors should probably start during treatment.


Assuntos
Composição Corporal , Cisplatino/uso terapêutico , Preferências Alimentares , Olfato , Paladar , Neoplasias Testiculares/tratamento farmacológico , Absorciometria de Fóton , Adulto , Apetite , Índice de Massa Corporal , Estudos de Casos e Controles , Dieta , Humanos , Fome , Hormônio Luteinizante/sangue , Masculino , Avaliação Nutricional , Sobrepeso/etiologia , Inquéritos e Questionários , Neoplasias Testiculares/complicações , Testosterona/sangue
4.
Appetite ; 105: 392-9, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27298084

RESUMO

BACKGROUND: Chemotherapy can affect taste and smell function. This may contribute to the high prevalence of overweight and metabolic syndrome in testicular cancer survivors (TCS). Aims of the study were to evaluate taste and smell function and possible consequences for dietary intake, food preference, and body composition in TCS treated with cisplatin-based chemotherapy. METHODS: Fifty TCS, 1-7 years post-chemotherapy, and 50 age-matched healthy men participated. Taste and smell function were measured using taste strips and 'Sniffin' Sticks', respectively. Dietary intake was investigated using a food frequency questionnaire. Food preference was assessed using food pictures varying in taste (sweet/savoury) and fat or protein content. Dual-Energy X-ray Absorptiometry was performed to measure body composition. Presence of metabolic syndrome and hypogonadism were assessed. RESULTS: TCS had a lower total taste function, a higher bitter taste threshold, higher Body Mass Index (BMI), and more (abdominal) fat than controls (p < 0.05). No differences in smell function and dietary intake were found. Testosterone level was an important determinant of body composition in TCS (p = 0.016). CONCLUSION: Although taste function was impaired in TCS, this was not related to a different dietary intake compared to controls. Lower testosterone levels were associated with a higher BMI, fat mass, and abdominal fat distribution in TCS.


Assuntos
Composição Corporal , Sobreviventes de Câncer , Preferências Alimentares , Transtornos de Sensação/epidemiologia , Olfato/fisiologia , Paladar/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Glicemia/metabolismo , Comportamento de Escolha , Colesterol/sangue , Cisplatino/uso terapêutico , Estudos Transversais , Dieta , Seguimentos , Humanos , Hormônio Luteinizante/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/diagnóstico , Prevalência , Inquéritos e Questionários , Neoplasias Testiculares/tratamento farmacológico , Testosterona/sangue , Triglicerídeos/sangue , Adulto Jovem
5.
PLoS One ; 9(4): e93823, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24714107

RESUMO

The high failure rate of new market introductions, despite initial successful testing with traditional sensory and consumer tests, necessitates the development of other tests. This study explored the ability of selected physiological and behavioral measures of the autonomic nervous system (ANS) to distinguish between repeated exposures to foods from a single category (breakfast drinks) and with similar liking ratings. In this within-subject study 19 healthy young adults sipped from five breakfast drinks, each presented five times, while ANS responses (heart rate, skin conductance response and skin temperature), facial expressions, liking, and intensities were recorded. The results showed that liking was associated with increased heart rate and skin temperature, and more neutral facial expressions. Intensity was associated with reduced heart rate and skin temperature, more neutral expressions and more negative expressions of sadness, anger and surprise. Strongest associations with liking were found after 1 second of tasting, whereas strongest associations with intensity were found after 2 seconds of tasting. Future studies should verify the contribution of the additional information to the prediction of market success.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Bebidas , Desjejum/fisiologia , Expressão Facial , Paladar/fisiologia , Adolescente , Adulto , Emoções/fisiologia , Feminino , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Temperatura Cutânea/fisiologia , Adulto Jovem
6.
Plant J ; 43(5): 688-707, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16115066

RESUMO

Viral infection often results in typical symptoms, the biological background of which has remained elusive. We show that constitutive expression of the NSM viral movement protein (MP) of tomato spotted wilt virus in Nicotiana tabacum is sufficient to induce severe, infection-like symptoms, including pronounced deficiencies in root and shoot development. Leaves failed to expand and were arranged in a rosette due to the absence of internode elongation. Following the sink-source transition they accumulated excessive amounts of starch and developed fusing chlorotic patches in the mesophyll, resembling virus-induced chlorotic lesions. Eventually, the leaves became entirely white and brittle. With a combination of techniques, including photosystem II quantum-yield measurements, iontophoresis of symplasmic tracers, bombardment with pPVX.GFP and double immunolabelling it was shown that these symptoms correlated with the obstruction of NSM-targeted mesophyll plasmodesmata (Pd) in source tissues by depositions of 1,3-beta-D-glucan (GLU) or callose. Temperature-shift treatments (TST; 22-->32 degrees C), known to abolish chlorotic local lesions, also abolished the chlorotic 'superlesions' of transgenic plants and rescued plant development, by restoring the transport capacity of Pd through the action of 1,3-beta-D-glucanase (GLU-h) or callase. Return of these elongated, TST-recovered plants to 22 degrees C reintroduced superlesions and arrested shoot elongation, resulting in the formation of a rosette of clustered leaves at the shoot tip. Collectively, this indicates that the symptoms of NSM plants are self-inflicted and due to a basal defence response that counteracts prolonged interference of the MP with Pd functioning. This type of defence may also play a role in the formation of symptoms during viral infection.


Assuntos
Nicotiana/fisiologia , Nicotiana/virologia , Plasmodesmos/fisiologia , Tospovirus/metabolismo , Proteínas Virais/biossíntese , Expressão Gênica , Glucanos/metabolismo , Temperatura Alta , Fenótipo , Fotossíntese/fisiologia , Doenças das Plantas/virologia , Folhas de Planta/fisiologia , Folhas de Planta/ultraestrutura , Folhas de Planta/virologia , Proteínas do Movimento Viral em Plantas , Plantas Geneticamente Modificadas , Amido/metabolismo , Nicotiana/ultraestrutura , beta-Glucanas/metabolismo
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