Influência das culturas láticas no índice de proteólise do queijo minas frescal

Estudou-se, a influência de culturas láticas no índice de proteólise do queijo Minas Frescal, processado com leite não pasteurizado e pasteurizado. O emprego de culturas láticas na elaboração de queijo Minas Frescal pode ser indicado, uma vez que o índice de proteólise só se correlacionou com o tempo de conservação.

Demonstration of the cellular viability and safety of Enterococcus faecium CRL 183 in long-term experiments

Enterococcus faecium CRL 183, a strain isolated from NSLAB cheese starter, has been the focus of much research on its potential probiotic capacity, although its survival through the gastrointestinal tract has not been demonstrated so far. In order to determine the capacity of E. faecium CRL 183 to survive such conditions, this strain was administered daily to rats for 30 weeks. The experimental animals were divided into Group I: those that did not receive E. faecium, Group II: those that received a pure culture of E. faecium CRL 183 and Group III: animals that received E. faecium CRL 183 in the form of a fermented soy-based product. Faecal samples were collected at the beginning and at the 50%, 75% and 100% stages of the experimental period. Isolation and counts of Enterococcus were carried out on KF selective media. To distinguish the various Enterococcus species in the faeces, biochemical (API Strep 20) and molecular (PCR) tests were performed. Initially, E. faecium was absent from the intestinal flora of the rats; however, after 15 weeks of administration, E. faecium could be recovered from the faeces of Groups II and III, demonstrating that E. faecium CRL 183 was able to survive gastrointestinal transit under the study conditions. This is further evidence of the probiotic qualities of this strain. The safety of the strain was also investigated with regard to body weight and serum biochemical analysis.

Genetic Parameters For the Somatic Cells Count In the Milk of Buffaloes Using Ordinary Test Day Models

The buffaloes dairy milk production (BDMP) has increased in the last 20 years, mainly for the manufacturing of mozzarella cheese, which is recognized by its high nutritional quality. However, this quality can be affected by several factors i. e. high somatic cells count (SCC) provokes changes in the milk's constituents. As in bovine dairy milk, the SCC is used as diagnostic tool for milk quality; because it enables the diagnosis of sub-clinic mastitis and also allows the selection of individuals genetically resistant to that disease. Based on it, we collected information about SCC and BDMP along the lactation in Murrah breed buffaloes, during the period between 1997 and 2005. Curves were designed to estimate genetic parameters. These parameters were estimated by ordinary test-day models. There were observed variations in the estimated heritability for both characteristics the lowest score for somatic cells count (SSCC) was seen at first month (0.01) and the highest at sixth months (0.29 the genetic correlation between these traits varied from -1 at the 1 and 9(th) months to 0.31 and 0.30 in the2 and 4(th) month of lactation. Phenotypic correlations were all negative (-0.07 in the second month and up to -0.35 in the eighth month of lactation). These results showed that environmental factors are more important than genetics in explain SCC, for this reason, selection for genetic resistance to mastitis in buffalos based in SCC should not be done. In the other hand, negative phenotypic correlations demonstrated that as the SCC increased, the milk production decreased.

β-galactosidase immobilization on controlled pore silica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development of a novel fermented soymilk product with potential probiotic properties

The study was carried out to test the ability of Enterococcus faecium, Lactobacillus acidophilus, L. jugurti, Streptococcus thermophilus and L. delbrueckii ssp bulgaricus to decrease cholesterol in vitro and to grow in the presence of bile salts. Both properties were dependent on the species under study. The cultures were also inoculated into soymilk fortified with dry milk whey powder as single or mixed starters. The physicochemical and sensory evaluations of the fermented products showed that E. faecium plus L. jugurti (ratio 1:1) is the best combination, and this mixture also produces a 43% decrease in cholesterol. © Springer-Verlag 1999.

Kappa-casein gene study with molecular markers in female buffaloes (Bubalus bubalis)

Caseins comprise make up about 80% of the total protein content of milk and present polymorphism with change in the amino acid sequence. Within this abundance of proteins, kappa-casein is noteworthy, since it has been associated with differences in milk yield, composition and processing. The objective of this study was to observe the existence of polymorphism in the kappa-casein gene in female buffaloes. For this purpose, blood samples from 115 female buffaloes, collected with vacutainer by needle punctionure of the jugular vein, were used. for genomic DNA extraction was done from blood samples. The PCR-RFLP and SSCP techniques demonstrated that the studied animals were monomorphic for the kappa-casein gene. Only allele B was observed in these animals, which was present in homozygosis. Therefore, it was not possible to quantify the gene action on milk yield and its constituents. The monomorphism observed in the population studied would allow the development of a method to identify mixtures of cow and buffalo milk in mozzarella cheese production, especially because, in cattle, the kappa-casein gene is polymorphic. Copyright by the Brazilian Society of Genetics.

Características reológicas e sensoriais de bebidas lácteas funcionais

This research studied the effects of the independent variables whey protein concentrate - WPC (3.0; 3.5; 4.0%), skimmed milk powder - SMP (4.0; 5.0; 6.0%), and isolated soy protein - IPS (1.5; 2.0; 2.5%) on the rheological and sensorial characteristics of functional dairy beverages. In all tests 7% of sucrose was added to the ingredients. The rheological parameters were obtained in duplicate at the temperature of 10° C using a cone and plate rheometer, and fitted to the Power law model. The samples revealed a non-Newtonian fluid behavior both in the upward and downward curves, typical of a tixotropic fluid. The dairy beverages were submitted to a sensory analysis by a group of fifty untrained tasters who used a hedonic scale of nine points, the extremes being 1 - disliked extremely and 9 - liked extremely, in order to evaluate the following parameters: general acceptability; appearance and color; consistency; taste and aroma. The dairy beverage produced with 3% WPC, 6% SMP and 1.5% IPS, (treatment 3), was the one that obtained the best average score for those attributes and was preferred by the tasters. The variables SMP and IPS and the interaction between WPC and SMP presented a positive effect on the sensory consistency attributes: the higher amount of those ingredients in the formula the more the tasters liked the consistency.

Determinação de GMP e CMP* no leite por métodos espectrofotométrico (ANSM) e cromatográfico (HPLC) - parâmetros metodológicos (*glicomacropeptídeo e caseinomacropeptídeo)

Glycomacropeptide is a glycosilated fraction of bovine kappa-casein that remains soluble when milk is clotted by rennin. Determinations of milk sialic acid content are useful because its concentration reflects the amount of free GMP of milk. In normal milk these amounts are very low, 12 to 16 times lower than in sweet whey. Therefore, its determination may be applied to verify possible frauds with whey addictions, since it works as a fingerprint. With the description of a new spectrophotometric method for determination of free GMP (ANSM) occurred a simplification of procedures, being faster than others (HPLC method), without loss of accuracy. However, due to variations of glycosilation in kappa-casein between animals, during the lactation period, due to mastitis and yet due to proteolysis on milk, it was necessary to know these variations to interpret correctly the analytical results. It was analyzed 1,703 samples of producer's raw milk and 1,189 samples of processed milk (HTST and UHT). The results showed that normal milk from herd (producer's milk) have only small amounts of free GMP, with A470nm = 0.232±0.088 or 3.89±1.25 mg of sialic acid/L. The upper limit of this distribution was A = 0.496; thus every bigger value may represent a problem, being outside of normal distribution.

Proteinograma do soro lácteo de ovelhas da raça santa inês em diferentes fases de lactação

This study aimed to evaluate the influence of lactation phases on the proteinogram of whey protein in Santa Inês ewes. Ewes were accompanied in a semi-intensive system using the same sanitary and nutritional management evaluated at 15, 30, 60 and 90 days postpartum (end of weaning and lactation). Clinical examination of the mammary gland was carried out through and bacteriological culture. The screening of the material resulted in 44 milk samples of healthy glands concurrent negative by CMT and bacteriological culture exam. For obtaining the whey protein renin solution was used. The whey was fractionated into aliquots and kept in the -80C freezer to later separation of protein fractions. For determination of total protein of whey protein was employed the biuret, observing the linearity of the test. Separation of protein fractions was performed, using polyacrylamide gel containing sodium dodecyl sulfate (SDS-PAGE). Eigth protein were observed including lactoferrin, serum albumin, IgA, IgG (heavy chain IgG (IgG CP), light chain IgG (IgG CL), ß-lactoglobulin, a-lactalbumin and proteins identified as PM 15000 and PM 29000. No significant difference was observed at different stages of lactation in the following protein: IgA (P>0.3895), lactoferrin (P>0.1611), PM 29000 (P>0.4879), α-lactalbumin (P>0.0799) and PM15000 (P>0.4494). In total protein (P<0.0022), albumin protein (P<0.0377) and IgG (P<0.0354) it was observed a significant variation in the first moments of observations, in the ß-lactoglobulin protein (P<0.0005) there was significant variation with reduction of 15 to 30 days postpartum with progressive elevation until the last stage of lactation (90 days postpartum). The SDS-PAGE technique allowed the quantification of eigth whey proteins in health ewes. The protein fractions identified reflect the profile of whey to ovine species, with influence of stages of lactation in albumin, IgG and ß-lactoglobulin.

Produção de biofilme por Listeria monocytogenes isoladas de diferentes alimentos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Mineralização do soro ácido de leite em função do pH do solo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Perfil microbiano, físico-químico e análise das boas práticas de fabricação (BPF) de queijos minas frescal e ricota

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito do uso de Lactobacillus casei como cultura adjunta na qualidade tecnológica de queijo prato com reduzido teor de gordura

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Linguiça cuiabana: histórico e aspectos tecnológicos de fabricação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do uso de enzimas proteolíticas na maturação de queijo Prato com teor reduzido de gordura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)