Development of a mixed jussara and mango juice with added Lactobacillus rhamnosus GG submitted to sub-lethal acid and baric stresses.

This study evaluated the interference of sub-lethal acid (SLA) stress and high isostatic pressure (HIP) stress on the survival of Lactobacillus rhamnosus GG (LGG) in mixed jussara and mango juice with the pH adjusted to 3.0 and 3.5, during 90 days of storage at 6 °C. The SLA stress at pH 4.0 previously applied to the LGG cells had no effect on the survival of this bacterium in mixed jussara and mango juices. On the other hand, the application of 200 MPa/5 min/25 °C treatment to LGG cells was shown to be efficient in the cross protection of this bacterium in an acid medium. Pressures above 400 MPa/5 min/25 °C caused a reduction in the viability in an acid medium and lower pressures (< 100 MPa) showed similar results compared to control treatment in the LGG survival. No changes in pH, acidity and soluble solids were observed in mixed juices. In addition, these products showed elevated levels of anthocyanins, phenolic compounds and antioxidant capacity. This highlights the capacity of the HIP process to promote the cross protection of LGG in an acid medium.

Eficiência de suco de juçara e manga na veiculação de Lactobacillus rhamnosus GG ao trato gastrointestinal humano simulado por ensaio in vitro / Efficiency of juçara and mango juice in the delivery of Lactobacillus rhamnosus GG to the human gastrointestinal tract simulated by in vitro assay

Este trabalho avaliou a interferência do estresse subletal em pH ácido na sobrevivência de Lactobacillus rhamnosus GG em suco misto de juçara e manga com pH ajustado para 3,0 e 3,5 e a resistência desta bactéria ao trato gastrointestinal simulado in vitro durante 28 dias de armazenamento a 6,0 °C. O estresse ácido previamente aplicado nas células de L. rhamnosus GG não aumentou sua resistência ao trato gastrointestinal simulado in vitro e a bactéria apresentou viabilidade mínima de 3,89 Log UFC/mL após a passagem pela fase entérica II. Os tratamentos utilizados, bem como o tempo de armazenamento, não influenciaram (p>0,05) na viabilidade de L. rhamnosus GG. Portanto, o estresse ácido subletal aplicado não se mostrou eficaz no aumento da sobrevivência da bactéria até 28 dias de armazenamento, mas a mesma apresentou boa sobrevivência no suco em pH ácido, mesmo quando não submetida ao estresse prévio em pH 4,0 por 1 hora a 37 °C.

This work evaluated the interference of sublethal stress at acidic pH in the survival of Lactobacillus rhamnosus GG in mixed jussara and mango juice with pH adjusted to 3,0 and 3,5, and the resistance of this bacterium to the gastrointestinal tract simulated in vitro during 28 days of storage at 6.0 °C. The acid stress previously applied to the cells of L. rhamnosus GG did not increase its resistance to the simulated gastrointestinal tract in vitro and thebacterium had a minimum viability of 3.89 Log CFU/mL after passage through the enteric phase II. The treatments used, as well as the storage time, did not influence (p>0.05) the viability of L. rhamnosus GG. Therefore, the sublethal acid stress applied was not effective in increasing the survival of the bacteria until 28 days of storage, but it presented good survival in the juice at acid pH, even when not submitted to previous stress at pH 4.0 per 1 hour at 37 °C.

Caracterização química e perfil de ácidos graxos em cultivares de nogueira-macadâmia / Chemical characterization and fatty acids profile in macadamia walnut cultivars

A nogueira-macadâmia produz nozes de alto valor no mercado internacional, devido às características nutricionais de suas amêndoas, consideradas uma excelente fonte energética. O objetivo do trabalho foi realizar a caracterização química e o perfil de ácidos graxos em 22 cultivares de nogueira-macadâmia. As cultivares utilizadas foram: 'Edson', 'HAES 788 (Pahala)', 'Beaumont 695', 'Flor Rosa', 'IAC 9-20X', 'HAES 344 (Kau)', 'Cannon', 'IAC 9-20', 'C160', 'HAES 849', 'IAC 4-12B', 'HAES 816', 'Doroti', '791 Fuji', 'IAC 4-20 (Keaumi)', 'HAES 814', 'HAES 722', 'África', 'IAC Campinas-B', 'HAES 246 (Keauhou)', 'HAES 741 (Mauka)' e 'HAES 842'. Foram quantificados a umidade, extrato etéreo, proteína, cinza e fibra bruta, além disso, extração de óleo e o perfil de ácidos graxos. A maior quantidade de proteína foi registrada na cultivar 'IAC 9-20X'. Quanto ao teor de fibra bruta, as maiores porcentagens foram observadas nas cultivares 'HAES 741' e 'HAES 842'. As amêndoas de todas as cultivares de nogueira-macadâmia analisadas possuem ácidos palmítico e oleico.

The walnuts macadamia have a high value on the international market due to their almonds nutritional characteristics considered to be an excellent source of energy. The aim of this work was to evaluate the chemical composition and fatty acid profile of 22 cultivars of almond walnut macadamia. The cultivars tested were: 'Edson', 'HAES 788 (Pahala)', 'Beaumont 695', 'Flor Rosa', 'IAC 9-20X', 'HAES 344 (Kau)', 'Cannon', 'IAC 9-20', 'C160', 'HAES 849', 'IAC 4-12B', 'HAES 816', 'Doroti', '791 Fuji', 'IAC 4-20 (Keaumi)', 'HAES 814', 'HAES 722', 'África', 'IAC Campinas-B', 'HAES 246 (Keauhou)', 'HAES 741 (Mauka)' and 'HAES 842'. Moisture, fat, protein, ash and crude fiber were analyzed and also oil extraction and fatty acid profile. The highest amount of protein was recorded in 'IAC 9-20X'. The highest percentages of crude fiber content were observed in cultivars 'HAES 741' and 'HAES 842'. The kernels of all walnut macadamia cultivars showed palmitic and oleic acids.