Volatile profiles and odor impact compounds in cashew (Anacardium occidentale L.) water phase and natural essences

Orientadores: Maria Aparecida Azevedo Pereira da Silva, Maria Regina Bueno FrancoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Durante a etapa de concentração de sucos, juntamente com a água, são também perdidos compostos voláteis responsáveis pelo aroma e sabor característicos da fruta. Esses voláteis podem, no entanto, ser recuperados por condensação, gerando um subproduto conhecido como water phase. Quando submetida à destilação fracionada, a water phase recuperada durante o processamento de sucos pode gerar essências naturais (GRAS), de alto valor agregado, as quais, ao serem incorporadas a sucos e refrescos, aumentam a qualidade sensorial desses produtos. Infelizmente, as water phases geradas por empresas brasileiras de sucos tropicais como caju, maracujá, etc são subaproveitadas. Isso ocorre devido ao conhecimento insuficiente tanto da composição dos voláteis presentes nas mesmas, como das condições de destilação a que devem ser submetidas para a elaboração de essências. Assim, os objetivos do presente estudo foram: i) identificar por cromatografia gasosaespectrometria de massas (CG-EM) o perfil de voláteis presentes em waterphase de caju gerada por indústria nacional de suco, determinando por CG-olfatometria (CGO), a importância odorífera de cada volátil identificado e, ii) através de destilação fracionada de water phase de caju gerada por empresa nacional, elaborar essências naturais, caracterizando a qualidade sensorial das mesmas, bem como o perfil de voláteis. Três tipos de materiais foram analisados: i) water phase de caju gerada durante a concentração de suco utilizando-se recuperador de aromas; ii) um condensado aquoso obtido por simples condensação da água evaporada durante a etapa de concentração do suco de caju e, iii) nove essências naturais GRAS geradas através da destilação fracionada de uma water phase de caju, utilizando-se coluna de fracionamento a 1 atm de pressão atmosférica e temperatura de 98 ºC, com condensação a ¿ 6 ºC. Os compostos voláteis presentes nas amostras foram isolados através de extração líquido-líquido com diclorometano e concentrados sob fluxo de nitrogênio. Após avaliação sensorial por equipe treinada, os isolados foram analisados por cromatografia gasosa (CG) utilizando-se um cromatógrafo gasoso Varian modelo 3600, equipado com detector de ionização de chama (DIC) e coluna capilar com fase estacionária DB-Wax. A identificação dos compostos foi conduzida através de um cromatógrafo gasoso da marca SHIMADZU modelo 17-A, equipado com detector de massas QP-5000 e operando nas seguintes condições: voltagem de ionização de 70eV (ionização por impacto de elétrons), velocidade de scan de 1 scan s ¿1 e varredura realizada entre 35 e 350 m/z. Os isolados da water phase e de uma das essências foram submetidos à CG-olfatometria (CGO), onde cinco julgadores treinados utilizando a técnica tempo-intensidade Osme, avaliaram os odores presentes nos efluentes cromatográficos dos citados isolados. Os resultados revelaram na water phase a presença de 64 compostos voláteis, dos quais 52 apresentaram impacto odorífero no efluente cromatográfico. Cerca de 38% dos compostos voláteis eram ésteres, 23% álcoois e 15% ácidos. Os voláteis de maior impacto odorífero presentes na water phase foram: ácido 3-metil butanóico (descrito como vômito, chulé), 2- metil butanóico (vômito, chulé), ácido acético (abacaxi cozido, remédio), acetofenona (queijo, cera), 2-hidroxi hexanoato de etila (caju), 2-metil-4-pentenal (verde, fruta), heptanol (caju, fruta), trans-3-hexen-1-ol (verde, fruta), 3-metil-1-butanol (chulé, álcool isoamílico); trans-2-butenoato de etila (fruta, caju), 2-metil butanoato de etila (fruta, caju), octanol (perfume, flor), trans-2-hexenal (maria fedida, verde), cis-3-hexen-1-ol (grama, doce), 2-etil-1-hexanol (verde, erva), isovalerato de etila (caju, doce) , 2-etil acrilato de metila (maria fedida, verde) e octanoato de etila (grão, terra molhada). Assim, a presente water phase, por conter muitos voláteis odoríferos de aromas desejáveis em uma essência de fruta, possuía grande potencial para gerar essências naturais de caju de boa qualidade sensorial. No condensado aquoso foram identificados 27 compostos voláteis, sendo 40% álcoois, 27% ácidos e 23% ésteres. A grande quantidade de álcoois e ácidos aliado a pequena quantidade e concentração de ésteres presentes no condensado aquoso demonstram que o mesmo é uma matéria prima menos favorável para a produção de essências, mas ainda assim, passível de ser explorada para esse fim. Todas as essências elaboradas apresentaram baixa intensidade de aroma de caju. O isolado da essência com maior intensidade de aroma de caju entre as 9 elaboradas possuía 61 compostos voláteis, dos quais 36 apresentaram importância odorífera no efluente cromatográfico. Dos 32 voláteis identificados, 33% eram álcoois, 23% terpenos, 14% ésteres, 11% aldeídos. Dentre eles, os de maior impacto odorífero foram: carvona (descrita como grama, sauna), 2-metil- 1-butanol (caju fermentado, fermentado), linalol (mamão, perfume), 2-hidroxi-4-metil pentanoato de etila (caju, fruta), cis-geraniol (essência de caju, fruta, flor), nonanal (grama, verde), 3-metil-1-butanol (caju fermentado, ardido), octanol (perfume, fruta), 2-etil-1- hexanol (grão, óleo de amêndoa), crotonoato de etila (caju, fruta). O alto caráter ¿doce/alcoólico¿ reportado nesta essência pela equipe sensorial, em detrimento do aroma característico de caju, pode ser atribuído à grande proporção de álcoois e terpenos presentes na mesma, em detrimento dos ésteres, que normalmente são responsáveis por notas de aromas ¿frutais¿ em essências. Dentre outros fatores, a baixa proporção de ésteres nesta essência, pode ser atribuída à perda, degradação, ou oxidação dos mesmos durante o processo de destilação fracionada da essência, realizada a alta temperatura e pressão atmosférica. A temperatura de condensação utilizada durante o processo de destilação (-6°C) também pode não ter sido suficientemente baixa para recuperar estes compostos na essência. De um modo geral, os resultados da presente pesquisa revelam que ainda que empresas brasileiras estejam gerando water phase com grande potencial para elaboração de essências naturais de caju, o processo de destilação fracionada dessas water phases, embora não possa ser considerado complexo, não é trivial, e requer otimização. Pesquisas adicionais explorando condições de destilação a menores temperaturas e pressões são cruciais para a adequada transformação das water phases nacionais em essências GRAS de alta qualidade sensorialAbstract: During the juice concentration step, volatile compounds responsible for the aroma and flavour characteristics of the fruit are lost together with the water. These volatiles can however be recovered by condensation, producing a sub-product known as the water phase. When submitted to fractionated distillation, the water phase recovered during juice processing can produce natural essence (GRAS), of high economic value, which, on being incorporated into juices and soft drinks, can increase the sensory quality of these products. Unfortunately, the water phases produced by Brazilian companies producing tropical juices such as cashew and passion fruit juices are under-used, due to a lack of knowledge of the composition of the volatiles present and of the distillation conditions to which they should be submitted to elaborate the essences. Thus the objectives of the present study were: i) identify the profile of the volatiles present in the cashew water phase produced by a national juice industry using gas chromatography-mass spectrometry (GC-MS), determining the odoriferous importance of each volatile identified using GC-olfactometry, and ii) elaborate natural essences by way of fractionated distillation of the cashew water phase produced by a national company, characterising their sensory quality and the profile of the volatiles. Three types of material were analysed: i) the cashew water phase produced during juice concentration using an aroma recovery unit; ii) an aqueous condensate obtained by the simple condensation of the water evaporated off during the cashew juice concentration step, and iii) nine natural GRAS essences produced by the fractionated distillation of a cashew water phase, using a fractionation column at 1 atm of atmospheric pressure and a temperature of 98ºC, with condensation at ¿6ºC. The volatile compounds present in the samples were isolated by liquid-liquid extraction using dichloromethane and concentrated in a flow of nitrogen. After a sensory evaluation by a trained panel, the isolates were analysed by gas chromatography (GC) using a Varian model 3600 gas chromatograph equipped with a flame ionisation detector (FID) and a capillary column with a DB-Wax stationary phase. The compounds were then identified using a Shimadzu model 17-A gas chromatograph equipped with a QP-5000 mass detector operating under the following conditions: ionisation voltage of 70eV (ionisation by electron impact), scanning velocity of 1 scan s-1 scanning between 35 and 350 m/z. Compounds isolated from the water phase and from one of the essences were submitted to GC-olfactometry (GC-O), where five trained judges evaluated the odours present in the chromatographic effluent of the above cited isolates using the Osme time-intensity technique. Sixty-four volatile compounds were found in the water phase, of which 52 presented an odoriferous impact on the chromatographic effluent. About 38% of the volatile compounds were esters, 23% alcohols and 15% acids. The following volatiles of the water phase showed the greatest odoriferous impact: 3-methyl butanoic acid (described as smelling of vomit, smelly feet), 2- methyl butanoic acid (vomit, smelly feet), acetic acid (cooked pineapple, medicinal), acetophenone (cheese, wax), ethyl 2-hydroxy hexanoate (cashew), 2-methyl-4-pentenal (greens, fruity), heptanol (cashew, fruity), trans-3-hexen-1-ol (greens, fruity), 3-methyl-1- butanol (smelly feet, isoamyl alcohol); ethyl trans-2-butenoate (fruity, cashew), ethyl 2- methyl butanoate (fruit, cashew), octanol (perfume, flowery), trans-2-hexenal (stinky insect, greens), cis-3-hexen-1-ol (grass, sweet), 2-ethyl-1-hexanol (greens, herbal), ethyl isovalerate (cashew, sweet), methyl 2-ethyl acrylate (stinky insect, greens) and ethyl octanoate (grainy, wet earth). Thus since the water phase contained so many odoriferous volatiles with desirable aromas for a fruit essence, it showed considerable potential to produce natural cashew essence with good sensory quality. Twenty-seven volatile compounds were identified in the aqueous condensate, of which 40% were alcohols, 27% acids and 23% esters. The larger amounts of alcohols and acids allied to the smaller amount and concentration of esters present in the aqueous condensate, indicated that this was a less favourable raw material for the production of essences, although possibly still of some use for such ends. All the essences elaborated presented a low intensity of cashew aroma. The isolate from the essence with the greatest intensity of cashew aroma amongst the 9 elaborated had 61 volatile compounds, of which 36 presented odoriferous importance in the chromatographic effluent. Of the 32 volatiles identified, 33% were alcohols, 23% terpenes, 14% esters and 11% aldehydes. Amongst these, those with greater odoriferous impact were: carvone (described as smelling of grass, sauna), 2-methyl-1-butanol (fermented cashew, fermented), linalool (papaya, perfume), ethyl 2-hydroxy-4-methyl pentanoate (cashew, fruity), cis-geraniol (cashew essence, fruity, flowery), nonanal (grass, greens), 3-methyl-1- butanol (fermented cashew, pungent), octanol (perfume, fruit), 2-ethyl-1-hexanol (grainy, almond oil), ethyl crotonoate (cashew, fruit). The highly ¿sweet/alcoholic¿ character of this essence as reported by the sensory panel, in detriment of a characteristic cashew aroma, can be attributed to the high proportion of alcohols and terpenes present, in detriment of esters, which are the compounds normally responsible for the fruity notes of essences. Amongst other factors, the low proportion of esters in this essence could be attributed to their loss during the fractionated distillation of the essence, carried out at high temperatures and atmospheric pressure. In general the results of the present study revealed that even if Brazilian companies are producing cashew water phase with great potential for the elaboration of natural cashew essences, the fractionated distillation process of these water phases, although not complex, is not trivial and requires optimisation. Additional research is crucial, exploring distillation conditions at lower temperatures and pressures for an adequate transformation of these national water phases into GRAS essences with high sensory qualityDoutoradoConsumo e Qualidade de AlimentosDoutor em Alimentos e Nutriçã

Association Between Taste Sensitivity And Self-reported And Objective Measures Of Salt Intake Among Hypertensive And Normotensive Individuals.

This study investigated the gustatory threshold for salt and its relationship with dietary salt intake among hypertensive (n = 54) and normotensive (n = 54) subjects. Salt intake was evaluated through 24-hour urinary sodium excretion and self-reported measures (discretionary salt, Sodium- Food Frequence Questionnaire (Na-FFQ), and 24-hour recall). Detection and recognition thresholds were higher among hypertensive subjects, as well as the total sodium intake. Detection and recognition thresholds were positively related to discretionary salt and total intake of the group as whole. Hypertensive and normotensive subjects presented positive correlations between taste sensitivity and the different measures of salt intake. To conclude, a positive correlation exists between taste threshold and salt intake and both seem to be higher among hypertensive subjects. The combined use of methods of self-report and assessment of taste thresholds can be useful in health promotion and rehabilitation programs, by screening subjects at higher risk of elevated salt intake and the critical dietary behaviors to be targeted as well to evaluate the result of targeted interventions.201330121

Acceptability Of An Alimentary Supplement Of Whey-protein Concentrate And Tgf- β In Patients With Crohn's Disease.

The objective of this study was to evaluate the acceptability of an alimentary supplement of bovine whey-protein concentrate (WPC) and TGF- β , unavailable commercially, by patients with Crohn's disease (CD) and determine the chemical composition, solubility, and total amino acids content. The supplement was diluted in water, and an acceptance test was done to evaluate the aroma, flavour, and viscosity of the product using facial hedonic scale (nine-point scale), applied on 54 CD patients. The supplement composition indicated 73.3% protein, 10.5% fat, 2.2% ash, 6.3% water, and 7.7% carbohydrate. The supplement is presented as a good protein source and high content of essential amino acids. The average acceptance for all the attributes was between 5.0 and 6.0, and the flavour was mainly associated with soybean/grain, sour milk, and sweet/vanilla flavour. The results indicated that the supplement provided important nutritional properties for CD patients; however, for a large number of individuals to be encouraged to perform supplementation, it is essential to improve the sensory quality of the product. In order to do so, additional research is necessary to prevent the formation of volatiles which cause off-flavours or to mask undesirable aromas/flavours found in it.201394786

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost