Peanut skin extract reduces lipid oxidation in cooked chicken patties.

The objectives of this study were to evaluate the antioxidant capacity of peanut skin extract and its effect on the color and lipid oxidation of cooked chicken patties over 15 d of refrigerated storage. The extract was obtained using 80% ethanol and evaluated in terms of total phenolic content, reducing power based on the ferric reducing ability of plasma (FRAP) reagent, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. The patties were made with ground thigh fillets, chicken skin, and 2% salt. They were homogenized and divided into the following two groups: a control treatment without antioxidants and a peanut skin treatment with 70 mg gallic acid equivalent (GAE)/kg per patty. Analyses of the fatty acid profiles, instrumental colors (L*, a*, and b*) and thiobarbituric acid reactive substances (TBARS) were performed on d 1, 8, and 15 of storage at 1±1ºC. The peanut skin extract resulted in a phenolic content of 32.6±0.7 mg GAE/g dry skin, an antioxidant activity (FRAP) of 26.5±0.8 6 µmol Trolox equivalent/g dry skin, and an efficient concentration (EC50) of 46.5 µg/mL. The total unsaturated fatty acid was approximately 73%, and 39% of this fatty acid content was monounsaturated. The peanut skin extract slowed the decrease in the a* values (P<0.05) but reduced the L* and b* values compared to the control samples during storage (P<0.05). Lipid oxidation was minimized by the peanut skin extract (P<0.05), which resulted in a maximum value of 0.97 malondialdehyde (MDA)/kg compared to values that were close 19 mg MDA/kg patties in the control sample at the end of storage period. Thus, it can be concluded that although peanut skin extract causes little color change, it can be applied as a natural antioxidant to cooked chicken patties because it efficiently inhibits lipid oxidation in this product during refrigerated storage.

Effect of spray drying on the sensory and physical properties of hydrolysed casein using gum arabic as the carrier.

This study was aimed at spray drying hydrolysed casein using gum Arabic as the carrier agent, in order to decrease the bitter taste. Three formulations with differing proportions of hydrolysed casein: gum Arabic (10:90, 20:80 and 30:70) were prepared and characterized. They were evaluated for their moisture content, water activity, hygroscopicity, dispersibility in water and in oil, particle size and distribution, particle morphology, thermal behaviour (DSC) and bitter taste by a trained sensory panel using a paired-comparison test (free samples vs. spray dried samples). The proportion of hydrolysed casein did not affect the morphology of the microspheres. The spray drying process increased product stability and modified the dissolution time, but had no effect on the ability of the material to dissolve in either water or oil. The sensory tests showed that the spray drying process using gum Arabic as the carrier was efficient in attenuating or masking the bitter taste of the hydrolysed casein.

Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology

In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (10³ CFU/g). The encapsulated probiotics were unstable when they were stored at 20 °C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 °C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at -18 °C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved.

Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology.

In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (10(3) CFU/g). The encapsulated probiotics were unstable when they were stored at 20 °C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 °C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at -18 °C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved.

Stability of microencapsulated B. lactis (BI 01) and L. acidophilus (LAC 4) by complex coacervation followed by spray drying.

Microcapsules containing Bifidobacterium lactis (BI 01) and Lactobacillus acidophilus (LAC 4) were produced by complex coacervation using a casein/pectin complex as the wall material, followed by spray drying. The aim of this study was to evaluate the resistance of these microorganisms when submitted to the spray drying process, a shelf-life of 120 days at 7-37 degrees C and the in vitro tolerance after being submitted to acid pH (pH 1.0 and 3.0) solutions besides morphology of microcapsules. Microencapsulated microorganisms were shown to be more resistant to acid conditions than free ones. Microencapsulated L. acidophilus maintained its viability for a longer storage period at both temperatures. The microcapsules presented a spherical shape with no fissures. The process used and the wall material were efficient in protecting the microorganisms under study against the spray drying process and simulated gastric juice; however, microencapsulated B. lactis lost its viability before the end of the storage time.

Microencapsulation of L. acidophilus (La-05) and B. lactis (Bb-12) and evaluation of their survival at the pH values of the stomach and in bile.

Microcapsules were prepared using the probiotic microorganisms Lactobacillus acidophilus (La-05) and Bifidobacterium lactis (Bb-12) and the spray drying technique and cellulose acetate phthalate as the wall material. This study evaluated the resistance of these microorganisms to drying at three temperatures and also the in vitro tolerance of the free and microencapsulated form to pH values and bile concentrations similar to those found in the human stomach and intestine. With an air entry temperature of 130 degrees C and exit temperature of 75 degrees C, the number of viable cells of B. lactis was practically unaltered, whereas the population of L. acidophilus was reduced by two logarithmic cycles. B. lactis was more resistant to the drying process than L. acidophilus under all conditions tested. The morphology of the microcapsules was determined by scanning electron microscopy and the microcapsules presented a rounded external surface containing concavities, a continuous wall with no apparent porosity, average size of 22 microm, moisture content varying from 5.3 to 3.2% and water activity between 0.230 and 0.204. After inoculation into HCl solutions with pH values adjusted to 1 and 2, incubated anaerobically at 37 degrees C, and plated after 0, 1 and 2 h of incubation, microcapsules were effective in protecting the microorganisms, while the populations of both free microorganisms were eliminated after only 1 h at the acidic conditions. Microencapsulated B. lactis and L. acidophilus, both free and microencapsulated, were also resistant after 12h to bile solutions.

Development and sensory evaluation of soy milk based yoghurt.

Yoghurts were prepared by fermentation of soy milk using a mixed starter culture containing Lactobacillus bulgaricus and Streptococcus thermophilus. Soy milk at 9 degrees Brix was homogenised under pressure (17 MPa) and fermented with and without addition of sucrose (2.0 and 2.5 g per 100 g) for 4, 5, 6 and 7 hours. The yoghurts were evaluated in terms of sensory quality, pH, titrable acidity, phytic acid and oligosaccharides: A yoghurt with the best sensory quality was obtained using the homogenised soy milk with 2% sucrose addition and fermented for 6 h. Lactobacillus bulgaricus and Streptococcus thermophilus did not produce phytases and alpha-galactosidases at the experimental conditions, consequently, phytic acid and galactosides were not affected by the process.

Development and sensory evaluation of soy milk based yoghurt

Foram elaborados iogurtes através da fermentaçao de leite de soja, usando uma cultura mista de lactobacillus bulgaricus e Streptococcus thermophilus. O leite de soja com 9ºBrix foi homogeinizado sob pressao (17 MPa) e fermentado com e sem adiçao de sacarose (2,0 e 2,5g por 100g)por 4,5,6 e 7 horas. Os iogurtes obtidos foram analisados em relaçao as características sensoriais, pH, acidez titulável, fitatos e oligossacarídeos. Foi obtido um iogurte com óptimas qualidades sensoriais, a partir do leite de soja homogeinizado, com adicao de 2 por ciento de sacarose e fermentado por 6h. Os microrganismos utilizados nao produziram fitases e alfa-galactosidases e, consequentemente, os teores de alfa-galactosídeos e de filatos nao foram alterados pelo processamento

Characterization of two cell lines with distinct phenotypes and genotypes established from a patient with renal cell carcinoma.

Two human renal carcinoma cell lines have been established from the same patient. One cell line (CCF-RC1) was obtained from the primary tumor and the second (CCF-RC2) was established from cells of the renal vein effluent of the perfused tumorous kidney. Although they were established from the same patient, the cell lines differed in certain biological properties. They have been passaged up to 50 times in vitro for about two years. Each has an epithelial morphology and exhibits mutilayering. Cell cycle time of CCF-RC1 and CCF-RC2 was 34 and 36 h, respectively. They exhibited anchorage independent growth, and the plating efficiency of CCF-RC2 in soft agar was higher than that of CCF-RC1. Both lines induced tumors in nude mice at the site of s.c. injection closely resembling the original tumor in histological examination. Electron microscopic features of both tumors in nude mice were consistent with epithelial origin. Doubling time of CCF-RC1 and CCF-RC2 in nude mice was 11 and 12 days, respectively. CCF-RC1 and CCF-RC2 have hypotetraploid karyotype and modal numbers of 83 and 73, presenting two and three marker chromosomes, respectively. Immunocytology with commercial monoclonal antibodies against renal carcinoma (URO-3) and cytokeratin (Mac 6) showed positive reactions with both lines, suggesting that these cell lines derived from renal epithelium. A murine monoclonal antibody (2E11) was generated against CCF-RC2 by the hybridoma technique; 2E11 reacted with CCF-RC2, but not with CCF-RC1. These cell lines may provide a useful model for the study of tumor heterogeneity and its relationship to metastasis.