Numerical Model to Analyze the Physicochemical Mechanisms Involved in CO₂ Absorption by an Aqueous Ammonia Droplet

This article belongs to the Special Issue Mechanical and Biomedical Engineering in Paradigm[Abstract] CO₂ is the main anthropogenic greenhouse gas and its reduction plays a decisive role in reducing global climate change. As a CO₂ elimination method, the present work is based on chemical absorption using aqueous ammonia as solvent. A CFD (computational fluid dynamics) model was developed to study CO₂ capture in a single droplet. The objective was to identify the main mechanisms responsible for CO₂ absorption, such as diffusion, solubility, convection, chemical dissociation, and evaporation. The proposed CFD model takes into consideration the fluid motion inside and outside the droplet. It was found that diffusion prevails over convection, especially for small droplets. Chemical reactions increase the absorption by up to 472.7% in comparison with physical absorption alone, and evaporation reduces the absorption up to 41.9% for the parameters studied in the present work

Comparative studies on the fatty acid profile and volatile compounds of fallow deer and beef fermented sausages without nitrite produced with the addition of acid whey

This study aims to improve knowledge on fermented beef and fallow deer sausages and the effect of nitrite elimination and the addition of freeze dried acid whey on the fatty acid profile and volatile compounds. Three different formulations within each of the two product groups, made of beef and fallow deer meat, respectively, were prepared: control sample with sodium nitrite, sample without nitrite, and sample without nitrite and with the addition of freeze-dried acid whey powder (0.7%). After production, the sausages were subjected to analysis including proximate chemical composition, pH and water activity, Thiobarbituric Acid Reactive Substance (TBARS), fatty acid profile, and volatile compound determination. The fermented sausages were characterized by an average pH and water activity in the range of 5.23–5.79 and 0.910–0.918, respectively. Fallow deer sausages were characterized by a higher content of saturated and polyunsaturated fatty acids in comparison to beef sausages. The elimination of nitrite did not significantly affect the amount of volatile compounds in fermented sausages. However, the effect of the freeze-dried acid whey powder addition on the amount of some volatile compounds in uncured sausages was observed, in particular, that derived from bacterial metabolism.Axencia Galega de Innovación | Ref. IN607A2019 / 01Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) | Ref. CPD2016-0030Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED) | Ref. 119RT056

Application of proteomic technologies to assess the quality of raw pork and pork products: an overview from farm-to-fork

The quality assurance of pork meat and products includes the study of factors prior to slaughter such as handling practices, diet and castration, and others during the post-mortem period such as aging, storage, and cooking. The development over the last two decades of high-throughput techniques such as proteomics offer great opportunities to examine the molecular mechanisms and study a priori the proteins in the living pigs and main post-mortem changes and post-translational modifications during the conversion of the muscle into the meat. When the most traditional crossbreeding and rearing strategies to improve pork quality were assessed, the main findings indicate that metabolic pathways early post-mortem were affected. Among the factors, it is well documented that pre-slaughter stress provokes substantial changes in the pork proteome that led to defective meat, and consequently, novel protein biomarkers should be identified and validated. Additionally, modifications in pork proteins had a strong effect on the sensory attributes due to the impact of processing, either physical or chemical. Maillard compounds and protein oxidation should be monitored in order to control proteolysis and volatile compounds. Beyond this, the search of bioactive peptides is becoming a paramount goal of the food and nutraceutical industry. In this regard, peptidomics is a major tool to identify and quantify these peptides with beneficial effects for human health.CYTED | Ref. 119RT0568Axencia Galega de Innovación | Ref. IN607A2019/0

Effects of autochthonous Kluyveromyces lactis and commercial Enterococcus faecium adjunct cultures on the volatile profile and the sensory characteristics of short-ripened acid-curd Cebreiro cheese

Elaboráronse catro lotes de queixo tipo Cebreiro por duplicado a partir de leite pasterizado. Un lote control foi fabricado só cun cultivo iniciador comercial tipo O. Os outros tres lotes preparáronse co mesmo cultivo iniciador xunto con: (i) un cultivo comercial de Enterococcus faecium; (ii) un cultivo adxunto seleccionado de Kluyveromyces lactis, usado nunha etapa de premaduración do leite de elaboración; e (iii) unha combinación de ambos cultivos adxuntos. Os queixos elaborados co adxunto de lévedos caracterizáronse por valores máis altos de índices de proteolise xeral, pH e actividade da auga, e amosaron recontos de mesófilos totais e de bacterias lácticas polo menos 2 unidades logarítmicas maiores que os correspondentes aos lotes elaborados só con bacterias lácticas. Os perfís de compostos volátiles dos queixos elaborados con K. lactis distinguíronse polo seu alto contido en ésteres, alcohois de cadea ramificada, ácidos graxos, acetoína e 2-feniletanol. Estes lotes tiveron unha textura máis friable e adherente, e amosaron aromas diferenciados picante, a lévedo, alcohólico, acético e afroitado. Ademáis, a adición de enterococos semellou contribuir a acadar características sensoriais máis desexables. Os lotes fabricados con ambos cultivos adxuntos recibiron puntuacións máis altas nos parámetros preferencia de textura, intensidade de sabor, preferencia de aroma e sabor, e preferencia sensorial xeral. Os perfís sensoriais dos queixos elaborados con lévedos engadidos foron moi similares aos do queixo Cebreiro tradicional de leite cru de boa calidade sensorial.Xunta de Galici

Gut Microbiota of Great Spotted Cuckoo Nestlings is a Mixture of Those of Their Foster Magpie Siblings and of Cuckoo Adults

Diet and host genetic or evolutionary history are considered the two main factors determining gut microbiota of animals, although studies are scarce in natural populations. The system of great spotted cuckoos (Clamator glandarius) parasitizing magpies (Pica pica) is ideal to study both effects since magpie adults feed cuckoo and magpie nestlings with the same diet and, consequently, differences in gut microbiota of nestlings of these two species will mainly reflect the importance of genetic components. Moreover, the diet of adults and of nestling cuckoos drastically differ from each other and, thus, differences and similarities in their microbiotas would respectively reflect the effect of environmental and genetic factors. We used next-generation sequencing technologies to analyze the gut microbiota of cuckoo adults and nestlings and of magpie nestlings. The highest -diversity estimates appeared in nestling cuckoos and the lowest in nestling magpies. Moreover, despite the greatest differences in the microbiome composition of magpies and cuckoos of both ages, cuckoo nestlings harbored a mixture of the Operational Taxonomic Units (OTUs) present in adult cuckoos and nestling magpies. We identified the bacterial taxa responsible for such results. These results suggest important phylogenetic components determining gut microbiome of nestlings, and that diet might be responsible for similarities between gut microbiome of cuckoo and magpie nestlings that allow cuckoos to digest food provided by magpie adults.This work was supported by the Ministerio de Ciencia, Innovacion y Universidades and European (FEDER) funds (CGL2017-83103-P)

Application of Proteomic Technologies to Assess the Quality of Raw Pork and Pork Products: An Overview from Farm-To-Fork

The quality assurance of pork meat and products includes the study of factors prior to slaughter such as handling practices, diet and castration, and others during the post-mortem period such as aging, storage, and cooking. The development over the last two decades of high-throughput techniques such as proteomics offer great opportunities to examine the molecular mechanisms and study a priori the proteins in the living pigs and main post-mortem changes and post-translational modifications during the conversion of the muscle into the meat. When the most traditional crossbreeding and rearing strategies to improve pork quality were assessed, the main findings indicate that metabolic pathways early post-mortem were affected. Among the factors, it is well documented that pre-slaughter stress provokes substantial changes in the pork proteome that led to defective meat, and consequently, novel protein biomarkers should be identified and validated. Additionally, modifications in pork proteins had a strong effect on the sensory attributes due to the impact of processing, either physical or chemical. Maillard compounds and protein oxidation should be monitored in order to control proteolysis and volatile compounds. Beyond this, the search of bioactive peptides is becoming a paramount goal of the food and nutraceutical industry. In this regard, peptidomics is a major tool to identify and quantify these peptides with beneficial effects for human healthJosé M. Lorenzo and Daniel Franco are members of the HealthyMeat network, funded by CYTED (Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo) (ref. 119RT0568). Our thanks go to GAIN (Axencia Galega de Innovación, Xunta de Galicia, Spain) for supporting this research (grant number IN607A2019/01). Mohammed Gagaoua is grateful to the funding received from Marie Skłodowska-Curie, grant agreement no. 713654S

Effect of chestnuts level in the formulation of the commercial feed on carcass characteristics and meat quality of Celta pig breed

The effect of including chestnuts in the formulation of the feed on carcass characteristics and meat quality from 24 castrated males Celta pigs was studied. The inclusion of 15% of chestnut (CH15) improved (p0.05) differences except for the carcass length and ham length, for which the CH15 group proved to be the group with the longest sizes. The diet did not affect the physicochemical properties (colour parameters, water holding capacity and shear force) of longissimus dorsi muscle. The composition of some fatty acids of the longissimus dorsi muscle was affected by diet. The total saturated (35-38%) and total polyunsaturated fatty acids (8-10%) did not present differences. However, the increase of chestnut in the diet increased (p<0.05) the monounsaturated fatty acids in intramuscular fat (57% in CH25 vs. 53% in control and CH15). Within monounsaturated fatty acids, the C18:1n9 was the most influenced by the diet. The expression of the enzyme that synthesizes C18:1n9 depend on the composition of the diet. Therefore, the lower content of protein and the higher amounts of C18:1n9 and C18:2n6 in the chestnut could be explaining the greater content of C18:1n9 in muscle of chestnut-fed animals. The main conclusion is that including chestnuts in the diet would allow reduce production costs with no effect or even improving carcass measurements and meat qualityXunta de Galicia, The Regional Government (Project PGIDT00AGR17E)S

Essential oil variability in Iranian populations of Heracleum persicum Desf. ex Fischer: a rich source of hexyl butyrate and octyl acetate

Heracleum persicum Desf. ex Fischer seeds are a rich source of essential oils (EOs) with high antimicrobial and antioxidant effects. In order to determine the phytochemical variability in various Iranian H. persicum populations, seed samples were collected from 10 different climatic locations. The current study indicated that hexyl butyrate (20.9–44.7%), octyl acetate (11.2–20.3%), hexyl-2-methylbutyrate (4.81–8.64%), and octyl 2-methyl butyrate (3.41–8.91%) were the major components of the EOs. The maximum (44.7%) and the minimum (20.9%) content of hexyl butyrate were obtained from Kaleibar and Sari populations, respectively. Moreover, the octyl acetate content ranged from 2% (in Mahdasht) to 20.3% in Torghabeh population. The CA and PCA analysis divided the 10 Iranian H. persicum populations into three major groups. Populations from Khanghah, Kaleibar, Shebeilo, Showt, Mahdasht, and Amin Abbad showed a distinct separation in comparison with the other populations, having high contents of hexyl butyrate (39.8%) and low contents of octyl acetate (13.5%) (Chemotype II). According to correlation analysis, the highest correlation coefficient was among habitat elevation and hexyl butyrate content. In addition, the mean annual precipitation was negatively correlated with the content of hexyl butyrate. Although octyl acetate content showed high correlation with soil EC and mean annual temperature, it was not statistically significant. In general, in order to have plants with a high content of hexyl butyrate, it is recommended to harvest these plants from regions with high altitude and low rainfall such as Kaleibar

Characterization of volatile compounds of cooked wild Iberian red deer meat extracted with solid phase microextraction and analysed by capillary gas chromatography - mass spectrometry

Wild Iberian red deer meat demand and interest are increasing and, therefore, an in-depth characterization of meat quality is needed to meet consumer demands. The objective of the present work was to assess, for the first time, the volatile profile of cooked wild sport-hunted Iberian red deer meat. Twenty-three loin samples from male red deer (Cervus elaphus hispanicus) were cooked and the volatile profile was analysed using solid phase microextraction, followed by capillary gas chromatography-mass spectrometry. Fifty-five volatile compounds were found. The major ones in number and relative abundance were aldehydes (84%), followed by alcohols (11%), hydrocarbons (2.4%), ketones (1.7%), furans (0.34%) and sulphur compounds (0.18%). Hexadecanal was the major compound and other long-chain compounds such as (E)-2-tetradecen-1-ol or 2-pentadecanone were also reported in considerable abundance. Several compounds related to grass-based diets were identified (2,3-octanedione, hexadecane or 1-pentadecanol). Odour impact ratio of volatile compounds was calculated and dimethyl trisulphide, (E,E)-2,4-decadienal, decanal and dodecanal were the most odorant compounds affecting the flavour of the cooked deer meat.Gobierno Vasco | Ref. IT944-16Ministerio de Economía y Competitividad | Ref. RTC-2016-5327-2Axencia Galega de Innovación | Ref. IN607A2019/01CYTED | Ref. 119RT056