NEOS: An odour-induced affect scale for use in the cosmetic industry.

This work proposes an odour-induced affect scale for use in the cosmetic industry that relies on the approach that produced the UniGEOS, a universal odour-related emotional scale from the Swiss Center for Affective Sciences. The Natura Emotion and Odor Scale (NEOS) was built on experiments conducted with a larger set of participants (491) and a set of 35 scents that combine seven commercial perfumes from Natura & Co cosmetic company with 28 odours from different olfactory classes important for the cosmetic industry. The results showed the stability of 60 Emotion-Related terms in Brazilian Portuguese split into five emotion-related dimensions: Romance, Attention, Energy, Well-being and Negative feelings. The association of the scents evoking these five dimensions has direct implications in the design of new products.

Ce travail propose une échelle d'affect induite par des odeurs passible d'être utilisée dans l'industrie cosmétique. Cette échelle s'appuie sur l'approche qui a produit l'UniGEOS, une échelle affective universelle liée aux odeurs du Swiss Center for Affective Sciences. L'échelle Natura Emotion and Odor Scale (NEOS) a été construite sur la base d'expériences menées avec un plus grand nombre de participants (491) et un ensemble de 35 arômes combinant sept parfums commerciaux de la compagnie Natura & Co avec 28 odeurs de différentes classes olfactives importantes pour l'industrie cosmétique. Les résultats ont montré la stabilité de 60 termes liés aux émotions en portugais brésilien, répartis en cinq dimensions liées aux émotions : Romance, Attention, Énergie, Bien-être et Sentiments négatifs. L'association des arômes évoquant ces cinq dimensions a des implications directes dans la conception de nouveaux produits.

Context-dependent use of olfactory cues by foragers of Vespula germanica social wasps.

Food search is guided by cues from different sensory modalities, such as olfactory and visual. In social wasps, olfaction plays a key role in locating new resources. However, while several studies have focused on the importance of odours in predation, less is known about their role during scavenging, when spatial memories become a relevant guidance mechanism. Here, we investigated whether the use of odours during carrion exploitation by Vespula germanica wasps depends on whether they are locating or relocating the resource. By means of field choice experiments, we evaluated wasp response to odours: an odour eliciting a spontaneous aversive response, a learnt odour eliciting an appetitive response, and the conspecifics' odour eliciting an attractive response. Experiments were conducted in different contexts, i.e., during food localisation by naïve foragers, re-localisation of a resource at the learnt site and re-localisation of a resource that had been displaced from the learnt site. All olfactory stimuli evaluated markedly influenced foraging decisions in naïve wasps and in experienced wasps when the food was moved from the learnt location. However, odours were ignored during the wasp's return to the foraging site. These results suggest a cue hierarchy, in which local landmarks are more reliable to relocate carrion, while olfaction would be useful to locate novel resources or relocate a known source when spatial memories fail. Our findings demonstrate a context-dependent use of odours during carrion exploitation by V. germanica wasps and highlight the importance of spatial memories as an important factor modulating odour response.

Self-perceived and self-reported breath odour and the wearing of face masks during the COVID-19 pandemic.

OBJECTIVES: To assess the self-perception of breath odour (SPBO) and oral hygiene habits (OHHs) while the wearing of face masks during the COVID-19 pandemic. SUBJECTS AND METHODS: This cross-sectional study included 4647 individuals who answered a structured questionnaire containing demographic, medical and dental variables and self-perceived breath odour. Variables associated with changes in self-perceived breath odour, self-perceived halitosis and changes in OHHs were assessed through multivariate logistic regression. RESULTS: Changes in self-perceived breath odour were reported by 1572 individuals and were associated with smoking, systemic conditions, dry mouth, tongue coating, the period of face mask use and its interaction with prior thinking of having bad breath. Likewise, 645 individuals started to consider having bad breath. This was associated with the interaction between prior family/friends saying they have bad breath and period of face mask use. Changes in OHHs were strongly associated with changes in SPBO and starting to consider having bad breath. CONCLUSION: Changes in one's SPBO was associated with the wearing of face masks and was significant for changes in OHHs. Findings may be important to guide comprehensive preventive and therapeutic strategies in relation to oral health care.

Are you my mummy? Long-term olfactory memory of mother's body odour by offspring in the domestic cat.

Longevity of odour memories, particularly those acquired during early development, has been documented in a wide range of taxa. Here, we report that kittens of the domestic cat retained a memory into adult life of their mother´s body odour experienced before weaning. Kittens from 15 litters were tested when permanently separated from their mother at weaning on postnatal week 8, and tested again when 4 and 6 months and over 1 year of age. When presented with a simultaneous three-way choice between body odour of their own mother, of an unknown female of similar reproductive condition and a blank stimulus, weaning-age kittens sniffed the cotton swab with the odour of an unknown female longer. This preference, however, changed when as adults the subjects sniffed the cotton swab with their own mother's odour longer. We conclude that kittens form a long-lasting memory of the body odour of their mother, and by implication, that mothers retain an individual odour signature sufficiently stable across age and changes in their reproductive state to be distinguishable by their adult offspring. What this means in functional or cognitive terms is not yet clear. Does such "recognition" have a specific biological function and a specific cognitive representation? Or is it rather part of a more general phenomenon well known in (human) olfaction of odours that are familiar generally being judged more pleasant, and that might then influence olfactory-guided behaviour in a variety of contexts?

Assessment of odour emissions by the use of a dispersion model in the context of the proposed new law in Chile.

Chile is looking to define a regulatory framework for the odour emissions of various critical industrial activities. One of these is the sanitary sector, with 300 wastewater treatment plants (WWTP). The basis currently used by the Chilean environmental authority to assess odours is the set of odour emission factors (OEF) taken from the Dutch standard. The aim of this study was to compare these, used as a national reference, with our own OEF calculated from measurements using dynamic olfactometry of 41 WWTP. The dependence of OEF on operational variables such as flow rate and BOD5 was analysed in different plant processes. The current regulations were assessed under the two OEF scenarios for the 95th, 98th and 99.9th percentiles in the Temuco WWTP, using the WRF-CALPUFF modelling protocol. The OEF values of the emission sources showed no strong correlation with operating variables like BOD5 and wastewater flow rates in all plant sections. Our OEF values based on real measurements presented significant differences from the Dutch reference OEF, of the order of 6 UOe/m2/s. The odour emitting-units with the largest differences were the pre-treatment units, flow-splitting chamber and most units of the sludge processing sections. These new OEF offer an alternative paradigm for measuring emissions and an incentive to more accurate calculation of the emissions in critical units such as sludge treatment lines. When the WWTP studied in Temuco was assessed using the OEF calculated in this study, a difference of 1041 OUe/s was found above the odours emissions calculated using the Dutch reference database. Using the Dutch OEF, the odour immission concentrations at nearby receptors were not exceeded for the 95th and 98th percentiles; this might result in deficient environmental assessment under current Chilean laws. We therefore recommend that Chilean institutions should assess projects using the OEF calculated in this study.

First characterization of toxic alkaloids and volatile organic compounds (VOCs) in the cryptic dendrobatid Silverstoneia punctiventris.

BACKGROUND: Poison frogs are known for the outstanding diversity of alkaloid-based chemical defences with promising therapeutic applications. However, current knowledge about chemical defences in Dendrobatoidea superfamily has two sources of bias. First, cryptic, brown-colored species have been neglected in comparison to those conspicuously colored, and second, there has been little interest in characterizing metabolites other than alkaloids mediating defensive functions. In an effort to contribute to fill the gap of knowledge about cryptic species and broadening the spectrum of compounds analyzed we have applied head-space solid phase microextraction coupled to gas chromatography and mass spectrometry (HS-SPME/GC-MS) for extracting amphibian alkaloids and volatile organic compounds (VOCs) from Silverstoneia punctiventris. RESULTS: Using the skin from 8 specimens in 4 biological replicates we have found 33 different compounds. Twenty of them were classified as VOCs into 15 chemical classes including alkanes, alcohols, carbonyl compounds, methylpyridines, benzothiazoles, N-alkylpyrrolidines, pyrazines, and sesquiterpenoids, some of which were previously reported as repellents, defence compounds or defence pheromones in other organisms, and as sex pheromones in a treefrog. Interestingly, six of the remaining compounds were identified as alkaloids previously reported in other toxic/unpalatable dendrobatid frogs. CONCLUSIONS: This is the first report of alkaloids and VOCs found in the Silverstoneia genus, which has been assumed for decades as non-chemically defended. This study establishes HS-SPME/GC-MS as a new application for a simultaneous approach to amphibian alkaloids and VOCs in poison frogs while opens up new research questions to assess the co-occurrence of both type of compounds and to investigate the evolutionary significance of a defence gradient that includes olfactory avoidance, unpalatability, and toxicity in dendrobatids. In addition, our results show that amphibian alkaloids could have a dual function (olfactory at distance, taste by contact) never explored before neither in Silverstonaeia nor in any other dendrobatid species.

Investigation of metabolites associated with confinement odour in chilled vacuum-packed lamb by proton nuclear magnetic resonance (1H NMR) spectroscopy.

This study aimed to determine the profiles of water-soluble metabolites in lamb drip and meat by Nuclear Magnetic Resonance (NMR) spectroscopy, in order to better understand the confinement odour (CO) phenomenon in lamb meat on a molecular level. Thirty-five lamb legs were obtained from two New Zealand meat processing plants and stored for 11 to 13 weeks at temperatures ranging from -1.5 °C to +4.0 °C. A sensorial test classified meat samples as having CO, no odour (NO) or persistent odour (PO). Sixty-three and sixty-two metabolites were identified and quantified in drip and meat samples, respectively. Partial least squares canonical analysis (PLS-CA) showed that CO was correlated with meat and drip metabolites tyramine, formate, alanine, carnosine, urea, proline, aspartate, glutathione and nicotinate. CO was also positively associated with appearance and bloom, but not directly associated with pH, size of the bacterial population or with processing plant. Metabolites associated with CO/PO are substrates or products of glucose fermentation and amino acid catabolism.

Mitigation of diffuse CH4 and H2S emissions from the liquid phase of UASB-based sewage treatment plants: challenges, techniques, and perspectives.

Upflow anaerobic sludge blanket (UASB) reactors are considered to be a sustainable and well-established technology for sewage treatment in warm climate countries. However, gases dissolved in the effluent of these reactors, CH4 and H2S in some instances, are a major drawback. These dissolved gases can be emitted into the atmosphere downstream of the anaerobic reactors, resulting in odour nuisance and, in the case of H2S, corrosion, while in the case of CH4, increasing greenhouse gas emissions with a significant loss of potentially recoverable energy. In this sense, this study aims to provide a critical review of the recent efforts to control CH4 and H2S dissolved in UASB reactor effluents, with a focus on the different available techniques. Different desorption techniques have been tested for the removal/recovery of dissolved CH4 and H2S: diffused aeration, simplified desorption chamber, packed desorption chamber, closed downflow hanging sponge reactor, membrane contactor, and vacuum desorption chamber. Other recent publications addressing the oxidation of these compounds in biological posttreatments with simultaneous nitrification/denitrification of ammonia were also discussed. Additionally, the rationale of CH4 recovery was determined by energy balance and carbon footprint approaches, and the H2S removal was examined by modelling its emission and atmospheric dispersion.

Optimisation and field validation of odour-baited traps for surveillance of Aedes aegypti adults in Paramaribo, Suriname.

BACKGROUND: Emerging arboviral diseases like Zika, dengue and chikungunya that are transmitted by Aedes aegypti mosquitoes, are increasingly threatening human health. Blends of human-like synthetic chemical attractants can be used to attract host-seeking mosquitoes. The aim of this study was to test new combinations of traps and odour baits in the laboratory, followed by testing the best candidates in the field to improve Ae. aegypti monitoring and surveillance. METHODS: First, the BG-Suna trap was evaluated for capturing laboratory-reared Ae. aegypti by testing normal and inverted positions in screen cage tests. Secondly, the attractiveness of the MB5 blend, CO2, and their combination was tested. Thirdly, we tested the attractiveness of different trap types (BG-Suna, BG-Sentinel, MM-X and CDC light trap). Finally, we confirmed laboratory results in the field in Paramaribo, Suriname, using the MB5 and BG-Lure odour blends, CO2 and the BG-Sentinel and BG-Bowl trap using a Latin Square design. RESULTS: The MB5 blend in combination with CO2 outperformed traps baited only with CO2 or MB5 in screen cage tests (P < 0.0001). The BG-Sentinel trap performed equally well as the inverted BG-Suna and was taken to the field (P = 0.729). In the field, we captured Ae. aegypti, Cx. quinquefasciatus and Cx. nigripalpus. We confirmed the laboratory results and found that the combination of the MB5 blend and CO2 almost doubled Ae. aegypti female captures (P = 0.004) and more than doubled Culex spp. female captures (P = 0.005) compared to using only CO2. Interestingly, the MB5 blend outperformed the commercially available BG-Lure, in the BG-Sentinel (P < 0.001). The BG-Bowl also attracted Ae. aegypti when baited with the MB5 blend in similar numbers as the BG-Sentinel baited with the MB5 (P = 0.362). CONCLUSIONS: Our study demonstrated that the BG-Sentinel trap baited with the MB5 blend and CO2 outperforms the current golden standard (BG-Sentinel trap with BG-Lure) for monitoring Ae. aegypti females and males, in both laboratory and field experiments. The BG-Bowl baited with the MB5 blend is a good candidate for home use. Finally, the results show that CO2 is an indispensable component of the attractive blend.

Assessing the inter-annual variability of separation distances around odour sources to protect the residents from odour annoyance.

In recent years, there has been a growing concern about potential impacts on public health and wellbeing due to exposure to environmental odour. Separation distances between odour-emitting sources and residential areas can be calculated using dispersion models, as a means of protecting the neighbourhood from odour annoyance. This study investigates the suitability of using one single year of meteorological input data to calculate reliable direction-dependent separation distances. Accordingly, we assessed and quantified the inter-annual variability of separation distances at two sites with different meteorological conditions, one in Brazil and the other in Austria. A 5-year dataset of hourly meteorological observations was used for each site. Two odour impact criteria set in current regulations were selected to explore their effect on the separation distances. The coefficient of variation was used as a statistical measure to characterise the amount of annual variation. Overall, for all scenarios, the separation distances had a low degree of inter-annual variability (mean coefficient of variation values from 8% to 21%). Reasonable agreements from year to year were therefore observed at the two sites under investigation, showing that one year of meteorological data is a good compromise to achieve reliable accuracy. This finding can provide a more cost-effective solution to calculate separation distances in the vicinity of odour sources.

Assessment of volatile compounds and sensory characteristics of Mexican hibiscus (Hibiscus sabdariffa L.) calyces hot beverages.

This study was conducted to assess and correlate the sensory characteristics and volatile compounds of hot beverages from the calyces of four Mexican varieties of hibiscus (4Q4, Puebla Precoz, UAN 16-1, and Sudan). A panel of 10 judges, detected six flavour descriptors in all samples. Sensory studies revealed highly characteristic flavour profiles of these varieties. In order to obtain the extracts and further characterize the odour-active volatiles of the studied beverages, a simultaneous steam distillation and solvent extraction procedure followed by a GC-MS analysis was employed. A total of 104 volatile compounds were identified in all samples. By determining the odour activity values (OAVs) it was possible to identify compounds with high odor-activity in the beverages, such as: 2-furfural, 5-methyl-2-furfural, hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 1-octen-3-one, 1-octen-3-ol, 5-methyl-2(3H)-furanone, phenylacetaldehyde, nonanal, (E)-2-nonenal, geranylacetone, α-ionone and ß-ionone. Moreover, on the basis of their OAVs, the differences in odour profiles of beverages were predominately due to these odorants.

Olfactory discrimination between litter mates by mothers and alien adult cats: lump or split?

Mother cats can discriminate between their own and alien kittens using kittens' body odour. Here we ask whether they can also distinguish between body odours of kittens from the same litter. We conducted three experiments using the habituation-dishabituation technique with the odour of 1- and 7-week-old kittens of both sexes. In Experiment 1, we found no evidence that mothers discriminated among their own kittens of either age when presented three times with the odour of one individual (habituation trials) and then with the odour of a different individual (dishabituation or discrimination trial), even when the donor kittens were of different sex. In Experiment 2, alien adults of both sexes distinguished between 7 but not between 1-week-old litter mates. In Experiment 3, mothers distinguished between unknown litter mates in a similar and age-dependent manner to the animals of Experiment 2. We conclude that litter mates possess individual odour signatures that can be discriminated by adult cats, that these cues take some time to develop, but are not discriminated by their own mother, at least not during the pre-weaning period. Mothers possibly perceive and respond to a learned "nest"/litter odour shared by all litter mates or categorize the individual odours of their kittens as belonging to an "own kitten" category. That mothers did not discriminate between the odours of their own kittens but did so between individual kittens of alien litters suggests that different levels of processing olfactory information exist in mothers' ability to cognitively partition and differentially respond to such odours.

Evaluation of different air dosing strategies to enhance H2S removal in microaerobic systems treating low-strength wastewaters.

This study aimed to evaluate different air dosing strategies such as microaeration flow rates and air dosing points to enhance H2S removal in microaerobic systems treating low-strength wastewaters. Efficiency and stability of the reactors, as well as biogas quality, were assessed, and microbial community changes were evaluated using the PCR-DGGE technique. The results showed that the air dosing point affected the H2S concentration and that air dosing at the headspace promoted the highest H2S removal efficiency. The airflow rate also affected the process, since H2S concentration in the biogas was higher at 0.1 mL air.min-1 than at 0.3 mL air.min-1. The methane concentration in the biogas was also affected by both air dosing point and flow rate, since the lowest value was observed at the highest airflow rate of the headspace dosing point, due to dilution by the N2 influx applied to the system. The highest productivity and operational efficiency were observed at this air dosing point, with this airflow (HD0.3), which corroborates with the operational results and the ecological parameters, since the microaeration at this stage promoted high bacterial and archaeal species richness and diversity, optimum functional organization, high COD and H2S removal efficiencies.

Characterization of odour-active volatiles and sensory analyses of roasted oak (Quercus humboldtii Bonpl) acorns, a coffee substitute / Caracterización de los compuestos activos olfativamente y análisis sensorial de los frutos tostados del roble (Quercus humboldtii Bonpl), como una bebida sustituta de café

Background: Oak acorns are roasted and grounded to produce a powder that is used to prepare a coffee substitute beverage. Objective: To identify the odour-active volatiles of the powder derived from roasted acorns of Quercus humboldtii and to perform a quantitative descriptive analysis (QDA) of its appearance, odour, and taste. Methods: The odour-active volatiles of roasted oak acorn powder were extracted by SDE and analyzed by GC/MS and olfactory analyses (GC/O). Sensorial analyses of this beverage were done by QDA (Quantitative Descriptive Analysis). Results: Nineteen compounds were identified, showing acid, buttery/caramel, smoke/roasted, and fruity odour notes, which are common to those of roasted coffee. Ketones, aldehydes, aliphatic acids, furanic alcohols and pyrazines were identified as relevant for this coffee substitute beverage. The major volatile compounds were furfural, 5-methyl furfural, furfuryl alcohol, and 3-hydroxy-2-butanone, some of them related to the sugar breakdown by heating. Odour attributes characterized by QDA, were in agreement with those detected by GC-O (Gas Chromatography coupled to Olfactometry), but some off-taste notes were detected. Conclusions: The results of molecular sensory approach confirmed that this product resembles coffee; however, QDA analyses showed the presence of undesirable taste. More studies are needed in order to improve the taste quality of this coffee substitute.

Antecedentes: los frutos del roble se tuestan y muelen para producir un polvo que es empleado en la preparación de una bebida sustituta del café. Objetivos: identificar los compuestos volátiles activos olfativamente presentes en el polvo proveniente de los frutos tostados de Quercus humboldtii; así como llevar a cabo un análisis cuantitativo descriptivo (QDA) de la apariencia, olor y sabor de este polvo. Métodos: os compuestos volátiles activos olfativamente del polvo de los frutos tostados del roble se extrajeron por DES y se analizaron por CG-EM y análisis olfativo (CG-O). La caracterización sensorial de esta bebida sustituta de café fue realizada mediante el empleo de QDA. Resultados: se identificaron diecinueve compuestos y se evidenció la presencia de notas de olor como manteca/caramelo, ahumado/tostado y frutal, similares a las encontradas en el café tostado. Los componentes mayoritarios identificados para este sustituto de café fueron cetonas, aldehídos, ácidos alifáticos, alcoholes furánicos y pirazinas. Los compuestos mayoritarios detectados fueron furfural, 5-metil furfural, alcohol furfurílico y 3-hidroxi-2-butanona, algunos de ellos relacionados con la descomposición térmica de azúcares. Los atributos de olor caracterizados por QDA fueron similares a los detectados por CG-O, aunque se detectaron algunas notas de sabor desagradable. Conclusiones: los resultados del molecular sensory approach confirmaron que este producto se parece al café; sin embargo el QDA mostró la presencia de un sabor desagradable. Estudios adicionales son necesarios para mejorar la calidad del sabor de este sustituto de café.

Foraging behaviour of the exotic wasp Vespula germanica (Hymenoptera: Vespidae) on a native caterpillar defoliator.

Vespula germanica is a social wasp and an opportunistic predator. While foraging, these wasps learn and integrate different kinds of cues. They have successfully invaded many parts of the world, including native Nothofagus and Lophozonia forests located in the Andean-Patagonian region, where they forage on native arthropods. Perzelia arda, a lepidopteron defoliator of Lophozonia obliqua, uses the foliage to hide in and feed on. The purpose of this work is to study whether V. germanica use olfactory cues when foraging on P. arda. To do this, we used a Y-tube olfactometer and established three treatments to compare pairs of all combinations of stimuli (larvae, leaves with larval traces, and leaves without larval traces) and controls. Data were analysed via two developed models that showed decisions made by V. germanica and allowed to establish a scale of preferences between the stimuli. The analysis demonstrates that V. germanica wasps choose P. arda as larval prey and are capable of discriminating between the offered stimuli (deviance information criterion (DIC) null model = 873.97; DIC simple model = 84.5, n = 152). According to the preference scale, V. germanica preferred leaves with traces of larvae, suggesting its ability to associate these traces with the presence of the prey. This may be because, under natural conditions, larvae are never exposed outside their shelters of leaves and therefore V. germanica uses indirect signals. The presence of V. germanica foraging on P. arda highlights the flexible foraging behaviour of this wasp which may also act as a positive biological control, reducing lepidopteran populations.

Human exposure to hydrogen sulphide concentrations near wastewater treatment plants.

The hydrogen sulphide (H2S) levels from wastewater treatment plants (WWTPs) in Curitiba, Brazil have been quantified for the first time. H2S generated by anaerobic decomposition of organic matter in WWTPs is a cause for concern because it is an air pollutant, which can cause eye and respiratory irritation, headaches, and nausea. Considering the requirement for WWTPs in all communities, it is necessary to assess the concentrations and effects of gases such as H2S on populations living and/or working near WWTPs. The primary objective of this study was to evaluate the indoor and outdoor concentration of H2S in the neighbourhood of two WWTPs located in Curitiba, as well as its human health impacts. Between August 2013 and March 2014 eight sampling campaigns were performed using passive samplers and the analyses were carried out by spectrophotometry, presenting mean concentrations ranging from 0.14 to 32µgm-3. Eleven points at WWTP-A reported H2S average concentrations above the WHO recommendation of 10µgm-3, and 15 points above the US EPA guideline of 2µgm-3. At WWTP-B the H2S concentration was above US EPA guideline at all the sampling points. The I/O ratio on the different sampling sites showed accumulation of indoor H2S in some instances and result in exacerbating the exposure of the residents. The highest H2S concentrations were recorded during the summer in houses located closest to the sewage treatment stations, and towards the main wind direction, showing the importance of these factors when planning a WWTP. Lifetime risk assessments of hydrogen sulphide exposure showed a significant non-carcinogenic adverse health risk for local residents and workers, especially those close to anaerobic WWTPs. The data indicated that WWTPs operated under these conditions should be recognized as a significant air pollution source, putting local populations at risk.

Physicochemical and sensory (aroma and colour) characterisation of a non-centrifugal cane sugar ("panela") beverage.

Non-centrifugal cane sugar (NCS), also called "panela", is a high carbohydrate-content food obtained by boil evaporation of the sugar cane juice. This study was undertaken to assess physicochemical properties and sensory characteristics of panela beverage at two different concentrations. Evaluation of pH, °Brix, and colour (tristimulus colorimetry) was carried out in all panela drink samples. In order to characterise the odour-active volatiles of the beverage, a simultaneous steam distillation-solvent extraction method was applied using a mixture of diethyl ether-pentane (1:1,w/w) as solvent. The Aroma Extract Dilution Analysis revealed the presence of six odour-active compounds, being 2-methyl pyrazine the key aroma compound of this beverage. PCA (Principal Component Analysis) showed that there were no differences in the aroma and physicochemical properties (pH and °Brix) with respect to the geographical origin of analysed samples; however colour depends on heating during processing of NCS.

Pragmatic evaluation of odour emissions from a rendering plant in southern Brazil.

In the food industry and linked activities, environmental impacts relate mainly to the generation of liquid and gaseous effluents. Rendering plants, which process animal by-products, are strongly associated with malodorous emissions. Thus, effective odour-control technologies are required to minimise odour annoyance in nearby communities and thereby public complaints. In this paper, the effectiveness of a biofilter for the treatment of odours from a meat-rendering plant located in southern Brazil was evaluated based on German guideline VDI 3477:2004-11. Samples were collected upstream and downstream of the gas treatment system using a pragmatic approach in order to minimise the cost of such a study. Odour concentration was determined according to European standard EN 13725:2003. The results showed an OER of 8.82 × 108 ouE h-1 and odour removal efficiency lower than the established benchmark set by SEMA Resolution 054/2006, taken as reference for being the only Brazilian regulation to establish quantitative odour emission criteria. Enhancement of the biofiltration system and/or association with other odour abatement technologies are required to increase odour removal, limit impacts and comply with regulatory requirements. The paper also includes a discussion on the current odour regulation in Brazil.

Insulin effects on honeybee appetitive behaviour.

Worker honeybees (Apis mellifera) carry out multiple tasks throughout their adult lifespan. It has been suggested that the insulin/insulin-like signalling pathway participates in regulating behavioural maturation in eusocial insects. Insulin signalling increases as the honeybee worker transitions from nurse to food processor to forager. As behavioural shifts require differential usage of sensory modalities, our aim was to assess insulin effects on olfactory and gustatory responsiveness as well as on olfactory learning in preforaging honeybee workers of different ages. Adults were reared in the laboratory or in the hive. Immediately after being injected with insulin or vehicle (control), and focusing on the proboscis extension response, bees were tested for their spontaneous response to odours, sucrose responsiveness and ability to discriminate odours through olfactory conditioning. Bees injected with insulin have higher spontaneous odour responses. Sucrose responsiveness and odour discrimination are differentially affected by treatment according to age: whereas insulin increases gustatory responsiveness and diminishes learning abilities of younger workers, it has the opposite effect on older bees. In summary, insulin can improve chemosensory responsiveness in young workers, but also worsens their learning abilities to discriminate odours. The insulin signalling pathway is responsive in young workers, although they are not yet initiating outdoor activities. Our results show strong age-dependent effects of insulin on appetitive behaviour, which uncover differences in insulin signalling regulation throughout the honeybee worker's adulthood.

Inclusion of Yucca schidigera extract in diets with different protein levels for dogs.

This study evaluated the effects of inclusion of Yucca schidigera extract (YSE) in two diets with different levels of crude protein (CP) for dogs on facal odour, nutrient digestibility, ammonia concentration in feces and hematological and serum biochemical profiles. Twenty adults Beagles were used, distributed in a randomized block design in a 2 × 4 factorial design (two diets, 25% and 34% CP, and four YSE levels: 0, 250, 500 and 750 mg/kg) with five replicates, obtained during two experimental periods. The fecal odour reduced (P < 0.05) when 500 mg/kg of YSE was used in diets with higher CP. The inclusion of YSE reduced (P < 0.05) fecal ammonia, and the inclusion of 250 and 500 mg/kg YSE reduced intestinal gas. The inclusion of 750 mg/kg YSE increased the mean corpuscular hemoglobin (MCH), alanine aminotransferase (ALT) activity and tended to increase the serum cholesterol concentration, regardless of the protein level of the diets. There was no effect on the digestibility of nutrients, fecal consistency, nitrogen balance and thickness of the intestinal wall. The inclusion of 500 mg/kg YSE is effective in reducing fecal odour in dogs receiving diets with 34% of CP. Regardless of the protein content, YSE reduces fecal ammonia, but may cause adverse effects if included at higher doses.