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1.
Sci Rep ; 12(1): 21063, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36473923

RESUMEN

The fall armyworm (FAW; Spodoptera frugiperda) is one of the major agricultural pest insects. FAW is native to the Americas, and its invasion was first reported in West Africa in 2016. Then it quickly spread through Africa, Asia, and Oceania, becoming one of the main threats to corn production. We analyzed whole genome sequences of 177 FAW individuals from 12 locations on four continents to infer evolutionary processes of invasion. Principal component analysis from the TPI gene and whole genome sequences shows that invasive FAW populations originated from the corn strain. Ancestry coefficient and phylogenetic analyses from the nuclear genome indicate that invasive populations are derived from a single ancestry, distinct from native populations, while the mitochondrial phylogenetic tree supports the hypothesis of multiple introductions. Adaptive evolution specific to invasive populations was observed in detoxification, chemosensory, and digestion genes. We concluded that extant invasive FAW populations originated from the corn strain with potential contributions of adaptive evolution.


Asunto(s)
Spodoptera , Humanos , Animales , Spodoptera/genética , Filogenia , Asia , África , África Occidental
2.
Foods ; 11(19)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36230089

RESUMEN

One of the ingredients used for brewing is barley, which should be malted; it is considered the most polluting agricultural input. On the other hand, food wastage is today a widespread problem that causes significant environmental damage and also generates large economic losses worldwide. One of the most wasted food products is bread; it is estimated that hundreds of tons of bread are wasted every day worldwide. In this study, the brewing of ale beers with bread was carried out. For this purpose, up to 50% of the malt weight was replaced by different types of bread: wheat bread, whole wheat bread, rye bread, and corn bread. A physicochemical and sensory comparison was made with 100% malt ale beer. All beers brewed with bread had an alcoholic strength similar to that of the control beer, except the corn beer. Beers brewed with whole grain bread showed a higher antioxidant capacity and a higher total polyphenol content. The sensory analysis presented different profiles depending on the type of bread; in general, the addition of bread created a greater olfactory intensity in nose. Thus, it was found that it is possible to brew beer with bread substituting up to 50% of the malt. In addition, it was also shown that the beer brewed with whole wheat bread had similar characteristics to the control beer, even improving some beneficial health properties, representing a great advantage for the brewing industry all over the world.

3.
Foods ; 10(8)2021 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-34441504

RESUMEN

In brewing, the use of cereals (wheat, barley, maize, rice, sorghum, oats, rye or millet), pseudo-cereals (buckwheat, quinoa or amaranth) and tubers (sweet potato), as starch adjuncts, is being promoted for the production of a variety of high-quality beers, from sensory and nutritional points of view. The sensory properties of the obtained beer depend on the characteristics of each adjunct but also on the forms in which the adjunct is added: whole cereal, grits, malted, extruded grains, torrefied and syrup. Among these common forms, the extruded grains (maize or rice) produce a higher content of aroma compounds in beer. From a nutritional point of view, the use of non-conventional starch adjuncts, such as black rice, buckwheat or sweet potato, leads to an increase in the polyphenol content of the beer, and thus, its antioxidant capacity. Cereals such as maize, rice, sorghum or millet are the most promising for the production of gluten-free beers. A close relationship can be developed between the use of adjuncts in the beer industry and the use of commercial enzymes. Advances made by biotechnology to design new enzymes with different functionalities could be associated to a future increase in adjunct usage in brewing.

4.
Insects ; 11(12)2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-33255898

RESUMEN

Fall armyworm is one of the main pests of conventional and Bacillus thuringiensis (Bt) corn in many countries in the Americas, Africa, Asia and in Australia. We conducted diet-overlay bioassays to determine the status of susceptibility to four Bt proteins (Cry1A.105, Cry2Ab2, Cry1F and Cry1Ac) in three different populations of fall armyworm from Mexico, and one population from Puerto Rico. Bioassays showed that fall armyworms from Puerto Rico were resistant to Cry1F with a resistance ratio 50 (RR50) higher than 10,000 ng/cm2 and to Cry1Ac with a RR50 = 12.2 ng/cm2, displaying the highest median lethal concentration (LC50) values to all Bt proteins tested. The effective concentration 50 (EC50) values further confirmed the loss of susceptibility to Cry1F and Cry1Ac in this population. However, LC50 and EC50 results with Cry1A.105 and Cry2Ab2 revealed that fall armyworm from Puerto Rico remained largely susceptible to these two proteins. The Mexican populations were highly susceptible to all the Bt proteins tested and displayed the lowest LC50 and EC50 values to all Bt proteins. Our results suggest that Cry1F and Cry1Ac resistance is stable in fall armyworm from Puerto Rico. However, this population remains susceptible to Cry1A.105 and Cry2Ab2. Results with Mexican fall armyworms suggest that possible deployment of Bt corn in Mexico will not be immediately challenged by Bt-resistant genes in those regions.

5.
Commun Biol ; 3(1): 664, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33184418

RESUMEN

Understanding the genetic basis of insecticide resistance is a key topic in agricultural ecology. The adaptive evolution of multi-copy detoxification genes has been interpreted as a cause of insecticide resistance, yet the same pattern can also be generated by the adaptation to host-plant defense toxins. In this study, we tested in the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), if adaptation by copy number variation caused insecticide resistance in two geographically distinct populations with different levels of resistance and the two host-plant strains. We observed a significant allelic differentiation of genomic copy number variations between the two geographic populations, but not between host-plant strains. A locus with positively selected copy number variation included a CYP gene cluster. Toxicological tests supported a central role for CYP enzymes in deltamethrin resistance. Our results indicate that copy number variation of detoxification genes might be responsible for insecticide resistance in fall armyworm and that evolutionary forces causing insecticide resistance could be independent of host-plant adaptation.


Asunto(s)
Variaciones en el Número de Copia de ADN/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Spodoptera , Animales , Sistema Enzimático del Citocromo P-450/genética , Femenino , Genoma de los Insectos/genética , Nitrilos/farmacología , Piretrinas/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/genética
6.
J Sci Food Agric ; 100(10): 3971-3978, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32333388

RESUMEN

BACKGROUND: Nowadays, low alcohol and non-alcohol beer intake has increased due to expanding concerns about healthy diets. However, there are still appreciable differences between non-alcoholic beer and conventional beer, particularly regarding flavor. Vacuum distillation is commonly used to remove ethanol from the beer in industrial processes and it is used here. RESULTS: The presence of n-propanol, isobutanol, 3-methylbutanol, 2-methylbutanol, 2-phenylethanol, ethyl acetate, isoamyl acetate, and acetaldehyde, which are key compounds responsible for aroma and flavor of beer, have been analyzed using nuclear magnetic resonance (NMR) spectroscopy in commercial beers and also in the corresponding distillates and residual phases after dealcoholization. CONCLUSION: The compounds present in each phase were identified by monodimensional and bidimensional NMR spectra. The compounds that are completely removed or that remain in the residue of the conventional beers studied are described in detail. The presence of these compounds in dealcoholized beer would be beneficial in keeping the aroma and flavor in dealcoholized beer. © 2020 Society of Chemical Industry.


Asunto(s)
Cerveza/análisis , Aromatizantes/análisis , Espectroscopía de Resonancia Magnética/métodos , Destilación/instrumentación , Destilación/métodos , Etanol/análisis , Humanos , Odorantes/análisis , Gusto , Vacio
7.
Biomolecules ; 10(3)2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32143493

RESUMEN

Beer is one of the most consumed drinks around the world, containing a variety of compounds that offer both appreciated sensorial characteristics and health advantages. Important healthy compounds in beer are those with antioxidant properties that attenuate the content of free radicals produced as by-products in the human metabolism, exerting an appreciable effect against cancers or cardiovascular diseases. This work details a study of antioxidant compounds present in beer, focusing on the two main groups: phenols (including polyphenolic forms) and melanoidins, formed specifically during brewing as Maillard products. The fundaments of the most important methods to evaluate beer antioxidant activity, the main antioxidant compounds present in beer-especially those with healthy properties-and the new trends to increase beer antioxidant activity are also discussed.


Asunto(s)
Antioxidantes/química , Cerveza , Fenoles/química , Polímeros/química , Humanos
8.
Evodevo ; 10: 6, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30984364

RESUMEN

The great capability of insects to adapt to new environments promoted their extraordinary diversification, resulting in the group of Metazoa with the largest number of species distributed worldwide. To understand this enormous diversity, it is essential to investigate lineages that would allow the reconstruction of the early events in the evolution of insects. However, research on insect ecology, physiology, development and evolution has mostly focused on few well-established model species. The key phylogenetic position of mayflies within Paleoptera as the sister group of the rest of winged insects and life history traits of mayflies make them an essential order to understand insect evolution. Here, we describe the establishment of a continuous culture system of the mayfly Cloeon dipterum and a series of experimental protocols and omics resources that allow the study of its development and its great regenerative capability. Thus, the establishment of Cloeon as an experimental platform paves the way to understand genomic and morphogenetic events that occurred at the origin of winged insects.

9.
J Econ Entomol ; 112(2): 792-802, 2019 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-30535077

RESUMEN

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is one of the main pests of corn in many areas of the American continent. The reliance on pesticides to control fall armyworm has led to the development of insecticide resistance in many regions. We determined the resistance levels of fall armyworm to insecticides of different modes of action in fall armyworm populations from Puerto Rico and several Mexican states with different insecticide use patterns. Mexican populations that expressed higher resistance ratios (RR50) were: Sonora (20-fold to chlorpyriphos), Oaxaca (19-fold to permethrin), and Sinaloa (10-fold to flubendamide). The Puerto Rico population exhibited a remarkable field-evolved resistance to many pesticides. The RR50 to the insecticides tested were: flubendiamide (500-fold), chlorantraniliprole (160-fold), methomyl (223-fold), thiodicarb (124-fold), permethrin (48-fold), chlorpyriphos (47-fold), zeta-cypermethrin (35-fold), deltamethrin (25-fold), triflumuron (20-fold), spinetoram (14-fold). Spinosad (eightfold), emamectin benzoate and abamectin (sevenfold) displayed lower resistance ratio. However, these compounds are still effective to manage fall armyworm resistance in Puerto Rico. Fall armyworm populations from Mexico show different levels of susceptibility, which may reflect the heterogeneity of the pest control patterns in this country. The status of insecticide resistance in the fall armyworm from Puerto Rico indicates a challenging situation for the control of this pest with these insecticides in the close future. Lessons learned from this research might be applied in regions with recent invasions of fall armyworm in Africa.


Asunto(s)
Insecticidas , África , Animales , Resistencia a los Insecticidas , México , Puerto Rico , Spodoptera
10.
Artículo en Inglés | MEDLINE | ID: mdl-29988354

RESUMEN

For more than 20 years cotton has been the most widely sown genetically modified (GM) crop in Mexico. Its cultivation has fulfilled all requirements and has gone through the different regulatory stages. During the last 20 years, both research-institutions and biotech-companies have generated scientific and technical information regarding GM cotton cultivation in Mexico. In this work, we collected data in order to analyze the environmental and agronomic effects of the use of GM cotton in Mexico. In 1996, the introduction of Bt cotton made it possible to reactivate this crop, which in previous years was greatly reduced due to pest problems, production costs and environmental concerns. Bt cotton is a widely accepted tool for cotton producers and has proven to be efficient for the control of lepidopteran pests. The economic benefits of its use are variable, and depend on factors such as the international cotton-prices and other costs associated with its inputs. So far, the management strategies used to prevent development of insect resistance to GM cotton has been successful, and there are no reports of insect resistance development to Bt cotton in Mexico. In addition, no effects have been observed on non-target organisms. For herbicide tolerant cotton, the prevention of herbicide resistance has also been successful since unlike other countries, the onset of resistance weeds is still slow, apparently due to cultural practices and rotation of different herbicides. Environmental benefits have been achieved with a reduction in chemical insecticide applications and the subsequent decrease in primary pest populations, so that the inclusion of other technologies-e.g., use of non-Bt cotton- can be explored. Nevertheless, control measures need to be implemented during transport of the bolls and fiber to prevent dispersal of volunteer plants and subsequent gene flow to wild relatives distributed outside the GM cotton growing areas. It is still necessary to implement national research programs, so that biotechnology and plant breeding advances can be used in the development of cotton varieties adapted to the Mexican particular environmental conditions and to control insect pests of regional importance.

11.
Appl Environ Microbiol ; 82(4): 1023-1034, 2016 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-26637593

RESUMEN

Insecticidal protein genes from the bacterium Bacillus thuringiensis (Bt) are expressed by transgenic Bt crops (Bt crops) for effective and environmentally safe pest control. The development of resistance to these insecticidal proteins is considered the most serious threat to the sustainability of Bt crops. Resistance in fall armyworm (Spodoptera frugiperda) populations from Puerto Rico to transgenic corn producing the Cry1Fa insecticidal protein resulted, for the first time in the United States, in practical resistance, and Bt corn was withdrawn from the local market. In this study, we used a field-collected Cry1Fa corn-resistant strain (456) of S. frugiperda to identify the mechanism responsible for field-evolved resistance. Binding assays detected reduced Cry1Fa, Cry1Ab, and Cry1Ac but not Cry1Ca toxin binding to midgut brush border membrane vesicles (BBMV) from the larvae of strain 456 compared to that from the larvae of a susceptible (Ben) strain. This binding phenotype is descriptive of the mode 1 type of resistance to Bt toxins. A comparison of the transcript levels for putative Cry1 toxin receptor genes identified a significant downregulation (>90%) of a membrane-bound alkaline phosphatase (ALP), which translated to reduced ALP protein levels and a 75% reduction in ALP activity in BBMV from 456 compared to that of Ben larvae. We cloned and heterologously expressed this ALP from susceptible S. frugiperda larvae and demonstrated that it specifically binds with Cry1Fa toxin. This study provides a thorough mechanistic description of field-evolved resistance to a transgenic Bt crop and supports an association between resistance and reduced Cry1Fa toxin binding and levels of a putative Cry1Fa toxin receptor, ALP, in the midguts of S. frugiperda larvae.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Proteínas Bacterianas/toxicidad , Endotoxinas/toxicidad , Proteínas Hemolisinas/toxicidad , Resistencia a los Insecticidas , Plantas Modificadas Genéticamente/parasitología , Spodoptera/efectos de los fármacos , Zea mays/parasitología , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Endotoxinas/genética , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/enzimología , Proteínas Hemolisinas/genética , Unión Proteica , Puerto Rico , Spodoptera/fisiología , Estados Unidos
12.
Crit Rev Food Sci Nutr ; 56(8): 1379-88, 2016 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-25118090

RESUMEN

Beer consumers are accustomed to a product that offers a pleasant and well-defined taste. However, in alcohol-free and alcohol-reduced beers these characteristics are totally different from those in regular beer. Therefore, it is important to evaluate and determine the different flavor compounds that affect organoleptic characteristics to obtain a product that does not contain off-flavors, or taste of grass or wort. The taste defects in alcohol-free beer are mainly attributed to loss of aromatic esters, insufficient aldehydes, reduction or loss of different alcohols, and an indeterminate change in any of its compounds during the dealcoholization process. The dealcoholization processes that are commonly used to reduce the alcohol content in beer are shown, as well as the negative consequences of these processes to beer flavor. Possible strategies to circumvent such negative consequences are suggested.


Asunto(s)
Cerveza/análisis , Etanol/análisis , Gusto , Aldehídos/análisis , Ésteres/análisis , Manipulación de Alimentos/métodos , Humanos , Fenoles/análisis
13.
Pestic Biochem Physiol ; 122: 15-21, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26071802

RESUMEN

Fall armyworm (FAW) is a damaging pest of many economic crops. Long-term use of chemical control prompted resistance development to many insecticide classes. Many populations were found to be significantly less susceptible to major Bt toxins expressed in transgenic crops. In this study, a FAW strain collected from Puerto Rico (PR) with 7717-fold Cry1F-resistance was examined to determine if it had also developed multiple/cross resistance to non-Bt insecticides. Dose response assays showed that the PR strain developed 19-fold resistance to acephate. Besides having a slightly smaller larval body weight and length, PR also evolved a deep (2.8%) molecular divergence in mitochondrial oxidase subunit II. Further examination of enzyme activities in the midgut of PR larvae exhibited substantial decreases of alkaline phosphatase (ALP), aminopeptidase (APN), 1-NA- and 2-NA-specific esterase, trypsin, and chymotrypsin activities, and significant increases of PNPA-specific esterase and glutathione S-transferase (GST) activities. When enzyme preparations from the whole larval body were examined, all three esterase, GST, trypsin, and chymotrypsin activities were significantly elevated in the PR strain, while ALP and APN activities were not significantly different from those of susceptible strain. Data indicated that multiple/cross resistances may have developed in the PR strain to both Bt toxins and conventional insecticides. Consistently reduced ALP provided evidence to support an ALP-mediated Bt resistance mechanism. Esterases and GSTs may be associated with acephate resistance through elevated metabolic detoxification. Further studies are needed to clarify whether and how esterases, GSTs, and other enzymes (such as P450s) are involved in cross resistance development to Bt and other insecticide classes.


Asunto(s)
Proteínas Bacterianas/farmacología , Endotoxinas/farmacología , Proteínas Hemolisinas/farmacología , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Organofosfatos/farmacología , Spodoptera/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Secuencia de Bases , Resistencia a Múltiples Medicamentos/genética , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Endotoxinas/genética , Enzimas/metabolismo , Glutatión Transferasa/metabolismo , Proteínas Hemolisinas/genética , Inactivación Metabólica , Proteínas de Insectos/metabolismo , Datos de Secuencia Molecular , Compuestos Organotiofosforados/farmacología , Fosforamidas/farmacología , Puerto Rico , Spodoptera/genética , Spodoptera/metabolismo
14.
Food Res Int ; 76(Pt 3): 751-760, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28455060

RESUMEN

The coupled operation of vacuum distillation process to produce alcohol free beer at laboratory scale and Aspen HYSYS simulation software was studied to define the chemical changes during the dealcoholization process in the aroma profiles of 2 different lager beers. At the lab-scale process, 2 different parameters were chosen to dealcoholize beer samples, 102mbar at 50°C and 200mbar at 67°C. Samples taken at different steps of the process were analyzed by HS-SPME-GC-MS focusing on the concentration of 7 flavor compounds, 5 alcohols and 2 esters. For simulation process, the EoS parameters of the Wilson-2 property package were adjusted to the experimental data and one more pressure was tested (60mbar). Simulation methods represent a viable alternative to predict results of the volatile compound composition of a final dealcoholized beer.

15.
J Sci Food Agric ; 95(8): 1571-6, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25205443

RESUMEN

As the beer market is steadily expanding, it is important for the brewing industry to offer consumers a product with the best organoleptic characteristics, flavour being one of the key characteristics of beer. New trends in instrumental methods of beer flavour analysis are described. In addition to successfully applied methods in beer analysis such as chromatography, spectroscopy, nuclear magnetic resonance, mass spectrometry or electronic nose and tongue techniques, among others, sample extraction and preparation such as derivatization or microextraction methods are also reviewed.


Asunto(s)
Cerveza/análisis , Técnicas de Química Analítica/tendencias , Gusto , Técnicas Biosensibles/tendencias , Técnicas de Química Analítica/métodos , Cromatografía/tendencias , Nariz Electrónica , Humanos , Espectrometría de Masas/tendencias , Microextracción en Fase Sólida/tendencias , Análisis Espectral/tendencias
17.
Front Hum Neurosci ; 8: 274, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25071496
18.
Food Chem ; 157: 205-12, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24679772

RESUMEN

Non-alcohol beers show taste deficiencies in relation to regular (alcohol) beers as shown by consumer evaluation. In this study, multivariate statistical analysis of data obtained by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) measurements was applied to determining differential metabolites between two regular (R1 and R2) and their related low- and non-alcohol beers (F1 and F2, respectively) from a Spanish manufacturer, as well as between F1 and F2 and two non-alcohol beers (F3 and F4) from a non-Spanish producer. Principal component analysis (PCA) of data from UPLC-MS measurements with electrospray ionization in negative mode was able to separate the six beers. Sugar content was 6-fold and 2-fold higher in F2 and F1 than in R2 and R1, respectively. Isoxanthohumol and hop acid contents decreased in F2 as compared with R2 but kept in F1 similar to R1. Results are discussed in relation to valued taste characteristics of each beer type.


Asunto(s)
Cerveza/análisis , Cromatografía Líquida de Alta Presión/métodos , Etanol/análisis , Espectrometría de Masas/métodos , Metabolómica/métodos , Análisis Multivariante , Análisis de Componente Principal
19.
Int J Food Sci Nutr ; 65(6): 655-60, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24601667

RESUMEN

The demand for light beers has led brewers to innovate by developing light beer. However, these products are not widely accepted in Europe compared to North America and Australasia because of their lack of fullness in the taste and low bitterness compared with conventional beer. The lower levels of some important compounds, present in light beer, can explain these features since they are responsible for the characteristics of the beer. These include alcohol soluble proteins, oligosaccharides, glycerol, polyphenols, iso-α-acids, fusel alcohols and trihydroxy fatty acids. Light beer is produced by several methods, the most commonly used is the addition of glucoamylase to the wort before or during fermentation. This enzyme metabolizes residual carbohydrates (mainly dextrins) transforming them into fermentable sugars and reducing the caloric and alcohol content in this type of beer. Recently pilot studies have been carried out with genetically engineered yeast strains in which amylolytic genes are introduced into the yeast genome in order to metabolize carbohydrate residues. When introducing amylolytic genes, a better fermentability occurs although the fullness of flavor still becomes reduced.


Asunto(s)
Amilasas , Cerveza , Carbohidratos de la Dieta , Etanol/metabolismo , Organismos Modificados Genéticamente , Gusto , Levaduras , Amilasas/genética , Amilasas/metabolismo , Carbohidratos de la Dieta/metabolismo , Fermentación , Industria de Alimentos , Humanos , Levaduras/genética , Levaduras/metabolismo
20.
J Sci Food Agric ; 94(10): 1988-93, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24307135

RESUMEN

BACKGROUND: Iso-α-acids and their chemically modified variants are responsible for the bitterness of beer and play a disproportionately large role in the final quality of beer. The current study was undertaken to predict the degradation of commercial lager beers related to changes in the concentration of trans-iso-α-acids during storage by using high-pressure liquid chromatography. RESULTS: In the analysed beers the concentration of isohumulone (average concentration 28 mg L(-1)) was greater than that of isocohumulone (20 mg L(-1)) and isoadhumulone (10 mg L(-1)). The kinetic parameters, activation energy and rate constant, of the trans-iso-α-acids were calculated. In the case of dark beers, the activation energy for the degradation of trans-isocohumulones was found to be higher than for trans-isohumulones and trans-isoadhumulones, whereas in pale and alcohol-free beers activation energies for the degradation of the three trans isomers were similar. CONCLUSION: The loss of iso-α-acids can be calculated using the activation energy of the degradation of trans-iso-α-acids and the temperature profile of the accelerated ageing. The results obtained in the investigation can be used in the beer industry to predict the alteration of the bitterness of beer during storage.


Asunto(s)
Ácidos/química , Cerveza/análisis , Ciclopentanos/química , Diterpenos/química , Almacenamiento de Alimentos , Humulus/química , Cromatografía Líquida de Alta Presión , Humanos , Isomerismo , Gusto
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