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1.
Magn Reson Chem ; 57(9): 589-602, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30664274

RESUMO

Roasting of Coffea arabica L. seeds gives rise to chemical reactions that produce more than 800 compounds, some being responsible for the desired organoleptic properties for which the beverage called "coffee" is known. In the industry, the "roasting profile," that is, the times and temperatures applied, is key to influence the composition of roasted coffee beans and the flavour of the beverage made from them. The impact of roasting on the chemical composition of coffee has been the subject of numerous studies, including by nuclear magnetic resonance (NMR) spectroscopy. However, the roasting equipment and profiles applied in these studies are often far from real industrial conditions. In this work, the effects of two critical technological parameters of the roasting process, namely, the "development time" (the period of time after the "first crack," a characteristic noise due to seed disruption) and the final roasting temperature on coffee extracts, were investigated. Seeds were roasted at pilot scale according to 13 industrial roasting profiles and extracted in D2 O. The extracts were analysed by 1 H NMR experiments. The NMR spectra were compared using (a) quantitative analysis of main signals by successive orders of magnitude and (b) chemometric tools (principal component analysis, partial least squares and sparse-orthogonal partial least squares analysis). This allowed to identify compounds, which may serve as markers of roasting and showed that changes in chemical composition can be detected even for slight change in final temperature (~1°C) or in total roasting time (~25 s).

2.
Anal Bioanal Chem ; 411(9): 1677-1678, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30963216
3.
MethodsX ; 12: 102666, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38559386

RESUMO

Domestic-oriented research focusing on food requires methodologies that closely mimic practices occurring in home kitchens while meeting scientific standards. Currently however, there is a lack of methodologies that can be implemented in both laboratory and home environments. This paper proposes a method that fulfills the scientific requirements of repeatability and reproducibility, while utilizing commonly available materials and processes found in the average household. The method is applied to the preparation, boiling, and seasoning of roots of Daucus carota L. ("carrots"), which can be employed in various scientific fields with only minor adjustments. Three scientific experiments utilizing this methodology are presented, namely sensory evaluation, ionic chromatography measurements, and NMR experiments. In the existing literature, numerous protocols have been used for carrot sample preparation, hindering direct comparisons between studies. In this paper we would like to highlight the ability of the methodology to enhance comparability, as well as its potential utilization in other research applications. The main principles underlying the proposed methodology can also be extrapolated to prepare samples of several other vegetables or cereals.•Comprehensive guidelines for standardizing the shapes, lengths, and widths of carrots are outlined, ensuring minimal variability while preserving the integrity of the raw material.•The cooking method for carrots is tailored to utilize commonly available household materials, while meeting scientific standards required for research purposes.•Seasoning practices involving readily available domestic materials, like commercial salt, are suggested.

4.
Anal Bioanal Chem ; 410(25): 6339-6340, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30191277
5.
Plant Physiol Biochem ; 194: 708-721, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36566710

RESUMO

Successful human space exploration requires more products than can be taken as payload. There is a need, therefore, for in-space circular manufacturing. Requirements for this include limited resource inflow, from either Earth or other planets and the generation of minimal waste. The provision of nutritious food is a clear need for human survival on the Moon or Mars and is one of the most complex to solve. Demand in large quantities, constant and reliable provision of food requires the development of specialist agricultural technologies. Here, we first review the history of space farming over the past five decades. This survey assesses the technologies which have been tested under the harsh conditions of space, identifying which modern horticultural components are applicable for in-space plant growth. We then outline which plants have been grown and under what conditions, and speculate upon the types of plants that could be selected to best nourish astronauts. Current systems are focussed on experimentation and exploration, but do not yet provide turn-key solutions for efficient food production within a long-term space exploration scenario. With that take, this review aims to provide a perspective on how an engineered closed circular environmental life-support system (ECCLES) might be constructed. To exemplify the latter, nutrient auto accumulation by biofortification is proposed through the integration of space farming and space mining, which is uncharted on Earth.


Assuntos
Voo Espacial , Astronave , Humanos , Planetas , Agricultura , Horticultura
6.
Anal Bioanal Chem ; 408(17): 4467-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27307247
8.
Anal Bioanal Chem ; 408(27): 7543-7544, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27734154
9.
Anal Bioanal Chem ; 399(1): 483-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21046086

RESUMO

In order to determine the saccharide content of plant tissues, we studied a new non-destructive and fast analytical method that we call "direct quantitative proton nuclear magnetic resonance spectroscopy" (d q (1)H NMR): the application of quantitative proton nuclear magnetic resonance spectroscopy (q (1)H NMR) to non modified plant tissues along with capillary tubes containing a reference compound (for quantification) and deuterium oxide (for locking). Using this method, the saccharide content of samples of carrot (Daucus carota L.) roots was compared to the results given from similar samples by the formerly published q (1)H NMR determination of extracts obtained by the O'Donoghue/Davis method. The content in glucose and sucrose is significantly higher with the direct method than when an extraction step is included; the content in fructose is not significantly different. If a possible detection of saccharides included in glycosylated biological compounds is to be excluded, a more complete extraction of saccharides is probably obtained using the direct method.


Assuntos
Carboidratos/análise , Daucus carota/química , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/análise , Espectroscopia de Ressonância Magnética/instrumentação , Raízes de Plantas/química
11.
Acc Chem Res ; 42(5): 575-83, 2009 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-19449900

RESUMO

Food preparation is such a routine activity that we often do not question the process. For example, why do we cook as we do? Why do we eat certain foods and avoid other perfectly edible ingredients? To help answer these questions, it is extremely important to study the chemical changes that food undergoes during preparation; even simply cutting a vegetable can lead to enzymatic reactions. For many years, these molecular transformations were neglected by the food science field. In 1988, the scientific discipline called "molecular gastronomy" was created, and the field is now developing in many countries. Its many applications fall into two categories. First, there are technology applications for restaurants, for homes, or even for the food industry. In particular, molecular gastronomy has led to "molecular cooking", a way of food preparation that uses "new" tools, ingredients, and methods. According to a British culinary magazine, the three "top chefs" of the world employ elements of molecular cooking. Second, there are educational applications of molecular gastronomy: new insights into the culinary processes have led to new culinary curricula for chefs in many countries such as France, Canada, Italy, and Finland, as well as educational programs in schools. In this Account, we focus on science, explain why molecular gastronomy had to be created, and consider its tools, concepts, and results. Within the field, conceptual tools have been developed in order to make the necessary studies. The emphasis is on two important parts of recipes: culinary definitions (describing the objective of recipes) and culinary "precisions" (information that includes old wives' tales, methods, tips, and proverbs, for example). As for any science, the main objective of molecular gastronomy is, of course, the discovery of new phenomena and new mechanisms. This explains why culinary precisions are so important: cooks of the past could see, but not interpret, phenomena that awaited scientific studies. For French cuisine alone, more than 25,000 culinary precisions have been collected since 1980. The study of the organization of dishes was improved by the introduction of a formalism called "complex disperse systems/nonperiodical organization of space" (CDS/NPOS). CDS describes the colloidal materials from which the parts of a dish are made; NPOS provides an overall description of a dish. This formalism has proven useful for the study of both scientific (examining phenomena to arrive at a mechanism) and technological (using the results of science to improve technique) applications. For example, it can be used to describe the physical structure of dishes (science) but also to examine the characteristics of classical French sauces (technology). Many questions still remain in the field of molecular gastronomy. For example, one "Holy Grail" of the field is the prediction of physical, biological, chemical, and organoleptic properties of systems from their CDS/NPOS formula. Another issue to be worked out is the relationship between compound migration in food and chemical modifications of those migrating compounds. These questions will likely keep scientists busy in the near future.

15.
Anal Bioanal Chem ; 398(7-8): 3139-53, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20972556

RESUMO

Solutions obtained by soaking onion (Allium cepa L.) bulbs samples in water are frequently consumed, either directly or as part of dishes, both at home or in the food industry. However, little information is available regarding the extracted metabolites and the extraction mechanisms. In this article, the composition of raw onion extracts and of aqueous solutions where raw onion tissues were soaked was investigated directly by quantitative proton nuclear magnetic resonance spectroscopy (q (1)H NMR). The assignment of NMR signals was performed, with less than 3% (in area) of unidentified peaks. Analyses of one-dimensional (1)H NMR spectra with additional two-dimensional NMR studies showed 20 regions of interest where 3 saccharides, 17 amino acids, and 5 organic acids were detected and quantified. Resonance assignment with chemical shift was done for each saccharide, as well as for each amino acid and organic acid, with additional work on spin-spin coupling pattern and on observed and not observed correlations from correlation spectroscopy studies. Quantification of saccharides was performed and qualified by works on peak decomposition algorithms. Complementary studies by high-performance liquid chromatography, mass spectroscopy and tandem mass spectroscopy, and thin layer chromatography and preparative layer chromatography were carried out in order to validate the NMR results on identification.


Assuntos
Aminoácidos/análise , Carboidratos/análise , Ácidos Carboxílicos/análise , Espectroscopia de Ressonância Magnética/métodos , Cebolas/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Espectrometria de Massas , Paladar
17.
Anal Bioanal Chem ; 406(1): 5-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24381060
19.
Anal Bioanal Chem ; 405(12): 3913-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23584099
20.
J Agric Food Chem ; 56(2): 314-20, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18081249

RESUMO

Using 1H nuclear magnetic resonance spectroscopy (1D and 2D), the two types of photosynthetic pigments (chlorophylls, their derivatives, and carotenoids) of "green beans" (immature pods of Phaseolus vulgaris L.) were analyzed. Compared to other analytical methods (light spectroscopy or chromatography), 1H NMR spectroscopy is a fast analytical way that provides more information on chlorophyll derivatives (allomers and epimers) than ultraviolet-visible spectroscopy. Moreover, it gives a large amount of data without prior chromatographic separation.


Assuntos
Phaseolus/química , Fotossíntese , Pigmentos Biológicos/análise , Carotenoides/análise , Clorofila/análise , Espectroscopia de Ressonância Magnética
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