Volatile changes in cv. Verdeal Transmontana olive oil: From the drupe to the table, including storage

This study focused on the volatile changes in cv. Verdeal Transmontana throughout the entire olive oil processing chain, from the drupe to olive oil storage up to 12 months, while correlating it with quality parameters and sensory quality. During crushing and malaxation, the volatiles formed were mainly “green-leaf volatiles” (GLVs), namely (E)-2-hexenal, hexanal, and 1-hexanol. Centrifugation and clarification steps increased the total volatile amounts to 130 mg kg−1. However, clarification also increased nonanal and (E)-2-decenal contents, two markers of oxidation, with a noticeable loss of phenolic compounds and oxidative stability. During storage, the total volatile amounts reduced drastically (94% at 12 months after extraction), together with the positive sensory attributes fruity, green, bitter, and pungent. Despite being classified as extra-virgin after one year of storage, peroxides and conjugated dienes were significantly higher while there was a reduction in antioxidant capacity as well as in phenolic compounds (less 50%) and oxidative stability (57%). The present work allowed concluding that the extraction process modulates the volatile composition of olive oil, with a concentration of volatiles at the clarification step. During storage, volatiles are lost, mainly eight months after extraction, leading to the loss of important sensory attributes.Ricardo Malheiro thanks FCT, POPH-QREN and FSE for the Post- Doctoral grant (SFRH/BPD/111901/2015). The authors thank the Casa Santo Amaro and their owners for the samples availability and the kindness for allowing the use of their facilities to extract the oils.info:eu-repo/semantics/publishedVersio

Biofloc technology on the zootechnical performance of tilapia: effect of strain and stocking density

The necessity of new technologies for the culture of aquatic organisms is becoming more evident, and thus, the biofloc system, a technic created to perform zero or minimum water exchange, starts to become more useful not only in shrimp culture, but also in finfish culture. This research purpose was to evaluate the growth and survival of Nile tilapia or “gray” (Oreochromis niloticus – GIFT strain) and red tilapia “Red Florida” strain (Oreochromis sp.) in biofloc system stocked in different densities (400 e 800/m3) in brackish water (8‰). Sixteen 26L plastic bins (19L usefull) were used and 192 fingerlings (3,06 ± 0,2 g) were stocked. A factorial experimental design was adopted (strain vs density) and a “macrocosm-microcosm” device system. For42 days, the animals were fed on a 45% CP commercial diet, three times per day. Water quality parameters and microbial community were monitored. At the end, proximate analysis of biofloc biomass was performed. The results suggested that Nile tilapia was the most appropriate for this phase (3-20 g) in biofloc system in brackish water. Furthermore, no negative effect was observed when 800 fish/m2 stocking density was considered.A necessidade de novas tecnologias para o cultivo de organismos aquáticos se faz cada vez mais presente, assim, o sistema de bioflocos, tecnologia concebida para trabalhar com nenhuma ou pouca renovação de água, começa a ter uso não somente na carcinicultura, mas também na piscicultura. O presente trabalho teve como objetivo avaliar o crescimento e sobrevivência de tilápias do Nilo (Oreochromis niloticus – linhagem GIFT) e tilápia vermelha (Oreochromis sp.) em sistemas de bioflocos sob diferentes densidades de estocagem (400 e 800/m3) em água salobra (8‰). Foram utilizadas 16 caixas plásticas de 26L (19L útil) e estocados 192 alevinos (3,06 ± 0,2 g). Adotou-se um delineamento fatorial (linhagem x densidade) e um sistema macrocosmo-microcosmo. Durante 42 dias os animais foram alimentados três vezes ao dia com ração comercial contendo 45% de proteína bruta. Foram monitorados os parâmetros de qualidade de água e o perfil de microrganismos da mesma ao longo do experimento. No final, foi realizada uma análise bromatológica da biomassa de bioflocos. Os resultados sugerem a tilápia do Nilo (O. niloticus) a mais adequadas para esta fase (3-20 g) em um sistema de bioflocos em água salobra. Observou-se ainda que não houve efeito negativo no crescimento quando empregado densidade de 800 peixes/m³

Análise energética em sistema de produção de suínos com aproveitamento dos desejos como biofertilizante em pastagem Energy analysis in a swine production system with use of manure as biofertilizer in pasture

O objetivo deste trabalho foi estimar a quantidade de energia para a produção de suínos, em ciclo completo, e o balanço energético do sistema com reaproveitamento dos resíduos gerados como biofertilizante, em área de pastagem, utilizando dados médios de cinco ciclos, em granja comercial no município de Diamantina - MG. Quantificou-se o coeficiente energético de cada componente envolvido no processo produtivo de suínos terminados, tratamento dos resíduos e produção de pastagem de Brachiaria decumbens, nas formas de ração, trabalho humano, energia elétrica, máquinas e equipamentos, combustíveis e lubrificantes, instalações, produção de suínos vivos e produção de Brachiaria decumbens. A quantidade média de energia para produzir 1 kg de suíno vivo foi de 53,35 MJ. De toda energia empregada no sistema, 76,03% (1.067.106,07 MJ) referem-se às entradas e 23,97% (331.400 MJ) às saídas, resultando em coeficiente de eficiência energética de 0,31. A energia transformada em suínos para abate correspondeu a 55,58% (184.200 MJ) das saídas, ao passo que a pastagem de Brachiaria decumbens assumiu o valor de 44,42% (147.200 MJ).<br>This work objective was to esteem the amount of energy employed in a complete cycle swine production and the energy balance of the system with utilization of the generated manure as biofertilizer in pasture area, by using five cycles' average data, in a commercial farm in Diamantina municipal district - MG Brazil. The energy coefficient of each involved component was quantified in the productive process of finished swine, residues treatment and Brachiaria decumbens pasture production, in the form of ration, human labor, electric power, machines and equipments, fuel and lubricants, buildings, finished swine production and Brachiaria decumbens production. The average quantity of energy to produce 1 kg of alive swine was of 53.35 MJ. Of total employed energy in the system 76.03% (1,067,106.07 MJ) refers to the inputs and 23.97% (331,400 MJ) refers to the outputs, resulting in an energy efficiency coefficient of 0.31. The energy converted in swine for abate corresponded to 55.58% (184,200 MJ) of the outputs, while the pasture of Brachiaria decumbens reached a value of 44.42% (147,200 MJ)