Encontrados 5 documentos, a visualizar página 1 de 1
Effects of various sugars added to growth and drying media upon thermotolerance...
Carvalho, Ana S.; Silva, Joana; Ho, Peter; Teixeira, P.; Malcata, F. Xavier; Gibbs, PaulThe aim of this research effort was to investigate the role of various sugar substrates in the growth medium upon thermotolerance and upon survival during storage after freeze-drying of Lactobacillus bulgaricus. Addition of the sugars tested to the growth medium, and of these and sorbitol to the drying medium (skim milk) was investigated so as to determine whether a relationship exists between growth and drying...
Relevant factors for the preparation of freeze-dried lactic acid
Carvalho, Ana S.; Silva, Joana; Ho, Peter; Teixeira, Paula; Malcata, F. Xavier; Gibbs, PaulThe industrial exploitation of lactic acid bacteria (LAB) as starter and/or probiotic cultures depends strongly on the preservation technologies employed, which are required to guarantee long-term delivery of stable cultures in terms of viability and activity. Freeze-dried preparations exhibit advantages relative to preparations made with other techniques in terms of long-term preservation, coupled with conveni...
Impedimetric method for estimating the residual activity of freeze-dried Lactob...
Carvalho, A. Sofia; Silva, Joana; Ho, Peter; Teixeira, Paula; Malcata, F. Xavier; Gibbs, PaulThe residual activity of Lactobacillus delbrueckii ssp. bulgaricus cultures was analysed using pH and various impedimetric methods (impedance detection time (IDT), conductance and capacitance) to quantify the loss in activity following freeze-drying. The large variation recorded in IDT values for similar levels of activity suggests that IDT is not an adequate parameter for estimating the culture's fermentative ...
Survival of freeze-dried Lactobacillus plantarum and Lactobacillus
Carvalho, A. Sofia; Silva, Joana; Ho, Peter; Teixeira, Paula; Malcata, F. Xavier; Gibbs, PaulNo significant differences were observed in the viability of Lactobacillus plantarum and Lactobacillus rhamnosus cells during freeze-drying in the presence or absence of inositol, sorbitol, fructose, trehalose, monosodium glutamate and propyl gallate. However, survival was higher during storage when drying took place in the presence of these compounds. Sorbitol produced more significant effects than the other c...
Changes in colour and phenolic composition during the early stages of maturatio...
Ho, Peter; Silva, Maria da Conceição M.; Hogg, Timothy A.Differences in colour and phenolic composition during the maturation of port in oak wood, stainless steel and glass were examined for a period of 311 days at 18 °C. Principal component analysis (PCA) was used in variable selection, data reduction and data analysis. Nine out of 13 colour and phenolic variables were heavily loaded on PC1 (76.1% of explained variance), and a plot of PC1 scores versus maturation ti...
| Financiadores do RCAAP | |||||||
|
|
|
|
|
|
||