94 research outputs found
Lactic Acid Bacteria and Yeast Inocula Modulate the Volatile Profile of Spanish-Style Green Table Olive Fermentations
In this work, Manzanilla Spanish-style green table olive fermentations were inoculated
with Lactobacillus pentosus LPG1, Lactobacillus pentosus Lp13, Lactobacillus plantarum Lpl15, the yeast
Wickerhanomyces anomalus Y12 and a mixed culture of all them. After fermentation (65 days),
their volatile profiles in brines were determined by gas chromatography-mass spectrometry analysis.
A total of 131 volatile compounds were found, but only 71 showed statistical differences between
at least, two fermentation processes. The major chemical groups were alcohols (32), ketones (14),
aldehydes (nine), and volatile phenols (nine). Results showed that inoculation with Lactobacillus
strains, especially L. pentosus Lp13, reduced the formation of volatile compounds. On the contrary,
inoculation with W. anomalus Y12 increased their concentrations with respect to the spontaneous
process, mainly of 1-butanol, 2-phenylethyl acetate, ethanol, and 2-methyl-1-butanol. Furthermore,
biplot and biclustering analyses segregated fermentations inoculated with Lp13 and Y12 from the
rest of the processes. The use of sequential lactic acid bacteria and yeasts inocula, or their mixture,
in Spanish-style green table olive fermentation could be advisable practice for producing differentiated
and high-quality products with improved aromatic profile.Gobierno de España-OliFilm-AGL-2013-48300-
Key odorants of the typical aroma of Sherry vinegar
A representative Sherry vinegar was analysed by gas chromatography-olfactometry
(GC-O). Two GC-O techniques were used targeting compounds with impact on the
perceived quality of Sherry vinegar, i.e. detection frequency and aroma extract
dilution analysis. A total of 108 aromatic notes were detected and 64 of them were
identified. Diacetyl, isoamyl acetate, acetic acid, and sotolon reached the highest
frequency and flavour dilution (FD) factors. Ethyl acetate accounted for the maximum
frequency but had only a FD factor of 4. Similarity tests were performed between the
Sherry vinegar and model solutions of all possible combinations of these compounds.
The highest value from the similarity test was observed when diacetyl, ethyl acetate
and sotolon were added simultaneously. The profile of this model solution and the
representative Sherry vinegar showed a good similarity in the general aroma
description, which emphasises the important contribution of these 3 compounds to
the global aroma of this vinegar
Influence of Irrigation Modalities (Irrigation Management and Dryland), Fruit Ripening, and Cultivation Modality (Organic and Conventional) on Quality and Chemosensory Profile of Hojiblanca and Picual Extra Virgin Olive Oils
A study with controlled field and authentic samples of olives, obtained in similar conditions of soil, climate, region, harvest, and with the same cultivation techniques and considering simultaneously different agronomic factors (olive variety, fruit ripening degree, irrigation, and organic or conventional production system) is performed to evaluate their influence on quality and added value of extra virgin olive oil (EVOO). Agronomical and physicochemical parameters, polyphenols, tocopherols, and fatty acid composition and volatile and sensory profiles are determined in Hojiblanca and Picual VOOs obtained from different fruit ripening degrees and different cultivation modalities (conventional with and without irrigation, and organic with irrigation). Among volatile compounds, 1-hydroxy-2-propanone, (E)-linalool oxide, and 2-acetylfuran are described for the first time in EVOO. The variable that most influences the chemosensory composition of EVOOs is the variety, followed by the stage of ripeness, and, within each variety, the cultivation modality. Organic irrigation differ from conventional modalities, showing significant differences in acidity, stability, tocopherol and polyphenol contents, fatty acid composition, and sensory attributes. Practical Applications: Results are of great importance, due to their applicability to the EVOO sector, allowing one to know the qualitative, chemical and organoleptic differences between organic and conventional EVOO, and factors that improve the quality and performance of EVOO.Junta de Andalucía P18-TP-285
Comparison of the novel thin film-solid phase microextraction and sorptive extraction methods for Picual and Hojiblanca olive oil volatile fraction analysis in headspace
For first time, the new device named thin film solid phase microextraction (TF-SPME) has been used to determine the volatile profile of the Picual and Hojiblanca varieties of extra virgin olive oils. To this end, different traditional sampling methods such as headspace sorptive extraction (HSSE) with polydimethylsiloxane (PDMS) and polyethyleneglycol-modified silicone (EG/Silicone) Twisters® have been compared with the TF-SPME devices coated with different extraction polymeric phases. PARADISe software was used as a non-targeting method to process all data. The best results were obtained by HSSE-PDMS and 2TF-SPME. Moreover, the 2TF-SPME extraction method achieved the most adequate results of linearity for most compounds, according to F-values, while the intermediate precision results were similar for both 2TF-SPME and HSSE-PDMS sampling methods. Different sensitivity was observed between both sampling methods depending on the volatile compound, without being clearly influenced by the polarity of them. Although both sampling methods enabled the main active aroma of olive oil to be determined and for them to be differentiated according to olive variety, the 2TF-SPME method appears to be the most suitable for this goal.CONICYT 1171227Junta de Andalucía P18-TP-285
Semi-wildlife gait patterns classification using Statistical Methods and Artificial Neural Networks
Several studies have focused on classifying behavioral
patterns in wildlife and captive species to monitor their
activities and so to understanding the interactions of animals
and control their welfare, for biological research or commercial
purposes. The use of pattern recognition techniques, statistical
methods and Overall Dynamic Body Acceleration (ODBA) are
well known for animal behavior recognition tasks. The reconfigurability
and scalability of these methods are not trivial, since a
new study has to be done when changing any of the configuration
parameters. In recent years, the use of Artificial Neural Networks
(ANN) has increased for this purpose due to the fact that they can
be easily adapted when new animals or patterns are required. In
this context, a comparative study between a theoretical research is
presented, where statistical and spectral analyses were performed
and an embedded implementation of an ANN on a smart collar
device was placed on semi-wild animals. This system is part
of a project whose main aim is to monitor wildlife in real
time using a wireless sensor network infrastructure. Different
classifiers were tested and compared for three different horse
gaits. Experimental results in a real time scenario achieved an
accuracy of up to 90.7%, proving the efficiency of the embedded
ANN implementation.Junta de Andalucía P12-TIC-1300Ministerio de Economía y Competitividad TEC2016-77785-
A Binaural Neuromorphic Auditory Sensor for FPGA: A Spike Signal Processing Approach
This paper presents a new architecture, design
flow, and field-programmable gate array (FPGA) implementation
analysis of a neuromorphic binaural auditory sensor, designed
completely in the spike domain. Unlike digital cochleae that
decompose audio signals using classical digital signal processing
techniques, the model presented in this paper processes information
directly encoded as spikes using pulse frequency modulation
and provides a set of frequency-decomposed audio information
using an address-event representation interface. In this case,
a systematic approach to design led to a generic process for
building, tuning, and implementing audio frequency decomposers
with different features, facilitating synthesis with custom features.
This allows researchers to implement their own parameterized
neuromorphic auditory systems in a low-cost FPGA in order to
study the audio processing and learning activity that takes place
in the brain. In this paper, we present a 64-channel binaural
neuromorphic auditory system implemented in a Virtex-5 FPGA
using a commercial development board. The system was excited
with a diverse set of audio signals in order to analyze its response
and characterize its features. The neuromorphic auditory system
response times and frequencies are reported. The experimental
results of the proposed system implementation with 64-channel
stereo are: a frequency range between 9.6 Hz and 14.6 kHz
(adjustable), a maximum output event rate of 2.19 Mevents/s,
a power consumption of 29.7 mW, the slices requirements
of 11 141, and a system clock frequency of 27 MHz.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130
Discrimination of defective dry-cured Iberian ham determining volatile compounds by non-destructive sampling and gas chromatography
Evaluation of dry-cured Iberian ham quality is carried out by means of the sense of smell of experts and a percentage of these hams are discarded due to odour defects. However, hams in cellars cannot be altered by sampling because they would be devaluated, which makes instrumental analysis difficult. Thus, the aim of this work is to assess the potential of headspace gas chromatography coupled to ion mobility spectrometry (HS-GC-IMS) or mass spectrometry (HS-GC-MS) to discriminate defective Iberian hams using a non-destructive sampling. Fifty hams from pigs fed with acorns were sampled in a real industry setting and were classified according to their condition (defective or non-defective). Validated classification rates of 80% and 100% using partial least squares discriminant analysis were obtained with HS-GC-IMS and HS-GC-MS, respectively, demonstrating the potential of the instrumental methods tested, which can be seen as complementary to the traditional olfactory technique. Furthermore, the volatile profile of spoiled Iberian hams was also determined; on average, spoiled pieces showed higher values of nonanal and decanal. Besides that, formic acid was only detected in spoiled pieces. These results might lead to an easier discrimination of spoilage to guarantee the quality of Iberian hams on the market
Influence of the ripening chamber's geographical location on dry-cured Iberian ham's key odorants
Olfactometric and sensory analyses have been applied to study the possible influence of the ripening chamber’s geographical location on the aroma sensory profiles and key odorants of Iberian ham. Dry-cured Iberian ham was obtained from 3 acorn-fed pigs and, for the first time, both of the participating production facilities, located in two different Andalusian municipalities with different altitudes above mean sea level, processed one of the two hind legs from each pig. The descriptive sensory profile of orthonasal and retronasal odours was determined by trained panellists, while odour-active compounds were determined by gas chromatography/mass spectrometry-olfactometry (GC/MS-O). The results obtained showed that, separately, both techniques enable Iberian ham samples to be differentiated by their ripening chamber’s geographical location. For sensory analysis, retronasal sensory analysis appeared to be the most suitable for this goal, highlighting the “meat broth odour” and “roasted nuts odour” descriptors which presented significant differences between geographical locations for samples from all pigs. Moreover, ripening chamber’s geographical location characteristics and the initial composition of the raw material seemed to influence the content of some odour-active compounds. The odour-active compound identified as octane/acetone and isobutanol were conditioned by the ripening chamber’s geographical location, while decanal/2-ethyl-1-hexanol, 1-undecanol, 2-furanmethanol and cis-2-nonenal were also influenced by the individual pig itself. This study showed that slight climatological differences due to the location of the ripening chamber seem to have somewhat of an influence on the aromatic profile.Universidad de Sevilla VIPPIT-2019-I
ED-Scorbot: A Robotic test-bed Framework for FPGA-based Neuromorphic systems
Neuromorphic engineering is a growing and
promising discipline nowadays. Neuro-inspiration and
brain understanding applied to solve engineering
problems is boosting new architectures, solutions and
products today. The biological brain and neural systems
process information at relatively low speeds through
small components, called neurons, and it is impressive how
they connect each other to construct complex
architectures to solve in a quasi-instantaneous way
visual and audio processing tasks, object detection and
tracking, target approximation, grasping…, etc., with very
low power. Neuromorphs are beginning to be very promising
for a new era in the development of new sensors,
processors, robots and software systems that mimic
these biological systems. The event-driven Scorbot (EDScorbot)
is a robotic arm plus a set of FPGA / microcontroller’s
boards and a library of FPGA logic joined in a completely
event-based framework (spike-based) from the sensors to the
actuators. It is located in Seville (University of Seville) and
can be used remotely. Spike-based commands, through
neuro-inspired motor controllers, can be sent to the
robot after visual processing object detection and
tracking for grasping or manipulation, after complex
visual and audio-visual sensory fusion, or after performing
a learning task. Thanks to the cascade FPGA
architecture through the Address-Event-Representation
(AER) bus, supported by specialized boards, resources for
algorithms implementation are not limited.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130
Diversity of HLA Class I and Class II blocks and conserved extended haplotypes in Lacandon Mayans.
Here we studied HLA blocks and haplotypes in a group of 218 Lacandon Maya Native American using a high-resolution next generation sequencing (NGS) method. We assessed the genetic diversity of HLA class I and class II in this population, and determined the most probable ancestry of Lacandon Maya HLA class I and class II haplotypes. Importantly, this Native American group showed a high degree of both HLA homozygosity and linkage disequilibrium across the HLA region and also lower class II HLA allelic diversity than most previously reported populations (including other Native American groups). Distinctive alleles present in the Lacandon population include HLA-A*24:14 and HLA-B*40:08. Furthermore, in Lacandons we observed a high frequency of haplotypes containing the allele HLA-DRB1*04:11, a relatively frequent allele in comparison with other neighboring indigenous groups. The specific demographic history of the Lacandon population including inbreeding, as well as pathogen selection, may have elevated the frequencies of a small number of HLA class II alleles and DNA blocks. To assess the possible role of different selective pressures in determining Native American HLA diversity, we evaluated the relationship between genetic diversity at HLA-A, HLA-B and HLA-DRB1 and pathogen richness for a global dataset and for Native American populations alone. In keeping with previous studies of such relationships we included distance from Africa as a covariate. After correction for multiple comparisons we did not find any significant relationship between pathogen diversity and HLA genetic diversity (as measured by polymorphism information content) in either our global dataset or the Native American subset of the dataset. We found the expected negative relationship between genetic diversity and distance from Africa in the global dataset, but no relationship between HLA genetic diversity and distance from Africa when Native American populations were considered alone
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