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- Assessment of the prediction power of forced ageing methodology on lager beer aldehyde evolution during maritime transportationPublication . Aguiar, Dayana; Pereira, Ana C.; Marques, José C.The globalisation of the beer market forces brewers to have methodologies that rapidly evaluate the evolution of beer flavour stability. Commonly used forced ageing methods have limitations since temperature and transportation conditions (temperature, vibrations, long-distance travel, and other factors) impact beer quality. This study assessed the prediction power of a forced ageing methodology on the evolution of aldehydes during maritime transportation across four sample groups (maritime transport, storage simulation, and three ageing periods: 7, 21, and 28 days at 37 ◦C), which differed in their bottle-opening system (either crown cap or ring pull cap). The results revealed that forced ageing up to 28 days could estimate the evolution of phenylacetaldehyde, 3-methylbutanal, 2-methylpropanal, and hexanal during maritime transport. In contrast, the benzaldehyde content was consistently underestimated, on average, 0.8 times lower. In general, the ageing conditions significantly favoured the formation or liberation from a bound state, up to 2.2 times higher, of trans-2-nonenal, acetaldehyde, and 5-hydroximethylfurfural in comparison to the levels registered on exportation simulation beers. Moreover, forced-aged beers with ring pull caps developed quantifiable levels of nonanal and increased phenylacetaldehyde, benzaldehyde, and acetaldehyde content over time. Moreover, thermal stress induced a continuous increase in the extent of beer staling, up to seven times higher, in most samples.
- Evolution of staling aldehydes on lager beer stability: impact of maritime transport and storage condidtionsPublication . Aguiar, Dayana Nataly de Menezes; Marques, José Carlos Antunes; Pereira, Ana Cristina RebolaA estabilidade organolética da cerveja engarrafada é atualmente um dos principais desafios da indústria cervejeira. Não obstante à contribuição de inúmeras substâncias, os compostos carbonilos, em particular os aldeídos, são responsáveis por muitas das mudanças desfavoráveis e percetíveis ao consumidor. Estas modificações são favorecidas por temperaturas não refrigeradas, armazenamento durante períodos longos, vibrações induzidas pelo transporte, entre outros fatores. Atualmente, existem ainda poucos dados na literatura científica sobre o impacto das condições reais de transporte, nomeadamente impacto das vibrações e temperaturas não refrigeradas, na estabilidade organolética da cerveja. O presente trabalho teve como objetivo avaliar a evolução de 10 aldeídos em cerveja Lager engarrafada durante exportação por via marítima e armazenamento no destino. Para tal, simulou-se as condições reais que a cerveja produzida localmente é submetida, nomeadamente temperatura (19-30ºC), vibração (1.7 Hz) e tempo (até 120 dias). A análise dos compostos em estudo foi realizada por micro-extração em fase sólida seguida por cromatografia gasosa acoplada a espetrometria de massa. Os resultados obtidos revelaram que as condições de transporte (influência de tempo, temperatura e vibração) e armazenamento (tempo, temperatura) simuladas i) promoveram o aumento médio na concentração dos aldeídos de Strecker, de 65%, ii) enquanto os aldeídos formados a partir oxidação lipídica bem como o acetaldeído, regra geral, não apresentam variações significativas neste período. O aumento descrito em i) apresentou dois padrões: garrafas com abertura tradicional (carica) apresentavam valores médios de 131.6±9.9 e 190.3±9.4 µg/L enquanto garrafas com um sistema de abertura fácil 190.5±10.0 e 180.3±9.5 µg/L, após transporte e armazenamento respetivamente. O fenilacetaldeído foi o composto com maior variação nas condições estudadas, aumentando de 94.7±7.3 (cerveja fresca) para 143.6±8.0 e 168.9±8.9 µg/L, após transporte e considerando um período adicional de armazenamento, respetivamente. Adicionalmente, verificou-se que o procedimento de envelhecimento forçado tipicamente adotado, pode apresentar limitações a reproduzir as condições reais em alguns compostos. Em particular, destaca-se o benzaldeído, que em qualquer período de envelhecimento forçado, 7, 14 e 28 dias, apresentou concentrações, em média, inferiores, de 5.3±0.3 µg/L, 5.4±0.3 µg/L e 5.4±0.3 µg/L, respetivamente, em comparação com o teor real ao fim de 120 dias, de 6.4±0.4 µg/L.
- Assessment of Staling Aldehydes in Lager Beer under Maritime Transport and Storage ConditionsPublication . Aguiar, Dayana; Pereira, Ana C.; Marques, José C.: Beer flavor stability is greatly influenced by external temperature, vibrations, and longer delivery times. The present study assessed the impact of transport and storage conditions on staling aldehyde evolution in lager beers across five sample groups (fresh, transport, and storage simulation, and their controls), which differed in their bottle opening system (either crown cap or ring pull cap). Maritime transport conditions (45 days of travel, vibrations of 1.7 Hz, and warm temperatures (21–30 ◦C)) were simulated, together with storage time in a distributor’s warehouse (up to 75 days). The results revealed that the concentration of Strecker aldehydes increased more quickly after transport and storage simulation in beer bottles with the ring pull cap opening system, and the contents of 2-methylpropanal and 3-methylbutanal, in particular, were up to three times higher. Benzaldehyde content also increased significantly, by 33% on average, in these samples. Hexanal was only found in beers with a ring pull cap that underwent transport simulation. Further storage after transport simulation significantly reduced the content of 2-methylpropanal, 3-methylbutanal, and hexanal, by 73%, 57%, and 43%, respectively, suggesting the formation of a bound state. 5- hydroxymethylfurfural was continuously increased by 78.5% and 40.5% after the Transport and Transport & Storage simulations, respectively. Transport conditions lead to a slight increase, of 0.6 EBC units, in beer color.
- The importance of monitoring cortisol in the agri-food sector: a systematic reviewPublication . Aguiar, Dayana; Marques, Carlos; Pereira, Ana C.Cortisol monitoring in the agri-food sector is considered a valuable tool due to its direct correlation with growth, reproduction, the immune system, and overall animal welfare. Strategies to monitor this stress hormone and its correlation to food quality and security have been studied in fish farming and the livestock industry. This review discusses studies on monitoring cortisol in the food industry for the first time. The impact of cortisol on animal production, quality, and the security of food products, and the analytical procedures commonly implemented for sample pre-concentration and quantification by liquid chromatography coupled to mass spectrometry, are reviewed and discussed according to the results published in the period 2012–2022. Aquaculture, or fish farming, is the leading agri-food sector, where cortisol’s impact and usefulness are better known than in livestock. The determination of cortisol in fish not only allows for an increase in the production rate, but also the ability to monitor the water quality, enhancing the sustainable development of this industry. In cattle, further studies are needed since it has mainly been used to detect the administration of illicit substances. Current analytical control and monitoring techniques are expensive and often depend on invasive sampling, not allowing fast or real-time monitoring.