Rita de Cássia Ramos do Egypto Queiroga

Efeito de dietas com níveis crescentes de caroço de algodão integral sobre a composição química e o perfil de ácidos graxos da carne de cordeiros Santa Inês

Esta pesquisa foi realizada com o objetivo de avaliar o efeito da inclusao (0, 20, 30 e 40%) de caroco de algodao integral (Gossypium hirsutum) na dieta sobre a composicao quimica e o perfil de acidos graxos da carne de cordeiros Santa Ines. Foram utilizados 24 cordeiros machos nao-castrados (peso corporal inicial de 19,0 ± 0,2 kg e 4 meses de idade), todos criados em regime de confinamento em baias individuais. Os niveis de caroco de algodao integral nao afetaram a composicao centesimal e os percentuais de colesterol e fosfolipidios da carne ovina. Entretanto, houve diferenca entre os percentuais dos acidos graxos miristico, palmitico e linolenico e entre a relacao C18:0 + C18:1 / C16:0. Do ponto de vista nutricional, a utilizacao de caroco de algodao integral na dieta pode ser recomendada, durante periodos curtos, em niveis de ate 40% para ovinos em terminacao. Ressalta-se que o caroco de algodao integral e um subproduto economicamente viavel por apresentar baixo custo de producao em comparacao ao milho e a soja.

Influência do manejo do rebanho, das condições higiênicas da ordenha e da fase de lactação na composição química do leite de cabras Saanen

The objective of this trial was to evaluate the effect of lactation stage in the chemical and physical characteristics of milk from Saanen goats as well as to investigate the effects of flock management, milking sanitary conditions, and lactation phase in the milk fatty acid profile. Twenty goats were randomly assigned to four groups of five animals each. Flock management differed by the presence or absence of males in the groups while milking sanitary conditions differed either by a poor or by a good milking hygiene. Milk samples were collected at 35, 85 and 135 days of lactation. Results showed that milk yield was as expected at 135 days of lactation; peak milk production was observed at 35 days of lactation and decreased linearly as lactation progressed. Milk yield, milk fat content, and milk acidity all changed according to the lactation stage. Milking sanitary conditions and flock management did not affect the milk fatty acids profile. However, milk fatty acids profile differed at different lactation stages with the greatest content of saturated fatty acids at 85 days of lactation.

Nutritional and sensory characteristics of Minas fresh cheese made with goat milk, cow milk, or a mixture of both

This study aimed to assess and compare the nutritional, technological, and sensory characteristics of Minas fresh cheese made with goat milk, cow milk, or a mixture of the two stored in cold conditions for 21d. The yield and centesimal composition of the cheeses were not affected by the type of milk used in their preparation. Reductions were observed in the moisture content, pH, proteolysis index, and instrumental hardness; moreover, increases were observed in the syneresis, acidity index, and depth of proteolysis index in all cheeses. The percentages of caprylic, capric, oleic, and linoleic fatty acids were higher in goat milk cheese and cheese made with a mixture of goat and cow milk compared with cow milk cheese, and a sensory evaluation revealed differences in color, flavor, and aroma between the cheeses. The preparation of Minas fresh cheese with a mixture of goat and cow milk can be a viable alternative for dairy products in the market that can be characterized as high-quality products that meet consumer demands.

Comparative Protein Composition Analysis of Goat Milk Produced by the Alpine and Saanen Breeds in Northeastern Brazil and Related Antibacterial Activities

The protein composition of goat milk differs between goat breeds and could present regional trends. The aim of this study was to comparatively analyze the protein composition of goat milk produced by the Alpine and Saanen breeds in northeastern Brazil and to evaluate the antibacterial activity of its protein fractions. SDS-PAGE, 2-DE electrophoresis and RP-HPLC analyses revealed the absence of αs1-casein in the milk of both breeds and no differences between the αs2-casein, β-casein, β-lactoglobulin and α-lactalbumin profiles. The amounts of soluble proteins and β-casein hydrolysis residues were higher in Saanen milk. Only the protein fraction containing the largest amounts of casein (F60–90%) inhibited bacterial growth, with MIC values between 50 and 100 mg/mL. This study describe for the first time three important points about the goat milk protein of two Brazilian goat breeders: absence of α-s1 casein in the protein profile, differences between the milk protein composition produced by goats of Alpine and Saanen breeders and antibacterial activity of unbroken proteins (casein-rich fraction) present in these milk.

Chemical composition and fat profile of meat from crossbred goats reared under feedlot systems

This study aimed to evaluate the chemical quality and fat profile of meat from crossbred goats (native and exotic) reared under feedlot systems. Thirty-two entire male goats were divided in equal number into four racial groups: eight pure Boer breed, eight ¾ Boer + ¼ SPRD crossbred, eight ½ Boer + ½ SPRD crossbred and eight ½ Anglo Nubian + ½ SPRD crossbred. All goats were reared under feedlot system and slaughtered at the average age and live weight of 223 days and 29 kg, respectively. The chemical composition including moisture, protein, ash, fat, cholesterol, phospholipids and fatty acids was determined. The breed types had no significant effect on moisture, protein, ash, fat, cholesterol and phospholipids contents. However, the percentages of oleic and stearic acids and the MUFA/SFA ratio showed significant differences between the four breed groups, with percentages ranging from 0.72 for ¾ Boer + ¼ SPRD crossbred to 0.95 for ½ Boer + ½ SPRD crossbred. The oleic acid (C18:1) was found in the highest percentage in the fatty acid profile in goat meat, particularly for ½ Boer + ½ SPRD and ½ Anglo + ½ SPRD genotypes. The crossing of exotic Boer and Anglo Nubian breeds with the natives SPRD resulted in a goat meat of high quality, even at a ratio of 50%, since the goat meat showed low cholesterol percentage and high protein and unsaturated fatty acids contents.

Produção e composição química do leite de cabras mestiças Moxotó sob suplementação com óleo de licuri ou de mamona

Avaliou-se o efeito da inclusao de oleos de licuri ou de mamona na dieta sobre a producao, a composicao quimica do leite de cabras leiteiras e a viabilidade economica dessas dietas. No delineamento experimental foram utilizadas cabras Mesticas Moxoto distribuidas em quadrado latino 5 × 5 com duas repeticoes, composto de cinco dietas: uma controle, sem lipidio suplementar, e as demais com 3% ou 5% de oleo de licuri ou de mamona. A suplementacao com 5% de oleo de licuri reduziu a producao de leite, mas nao influenciou a producao de leite corrigida para 4% de gordura. A adicao de 3% de oleo de mamona reduziu o teor de gordura e de solidos totais em comparacao ao oleo de licuri, aumentando o teor de lactose. O teor de proteina do leite, no entanto, nao foi alterado pela adicao de oleo na dieta. Os indicadores economicos apontaram a dieta controle como a mais rentavel, no entanto, a suplementacao com 3% de oleo de licuri, em comparacao ao de mamona, pode ser interessante quando o leite se destina ao processamento, em virtude do maior teor de gordura.

Características físico-químicas e perfil lipídico do leite de cabras mestiças Moxotó alimentadas com dietas suplementadas com óleo de semente de algodão ou de girassol

The effects of cottonseed and sunflower oil supplementation on milk composition were tested using crossbred Moxoto goats. Experimental diets were as follows: control, without addition of oil; addition of 3% cottonseed oil; 5% cottonseed oil; 3% sunflower oil and 5% sunflower oil (%DM). Ten confined lactating goats were allotted to a double Latin square experimental design (5 × 5). Each period was comprised by 12 days of adaptation to the diet and three days of sampling in each period. Cottonseed oil supplementation at 5 %DM increased the fat content (4.99%) and the total solid (13.48%) of milk. However, the addition of sunflower oil at 5% promoted an increase in the linolenic acid (C18:3) concentrations. Therefore, the vegetal oil addition in diets for native goats promoted an increase in the percentage of milk fat and in unsaturated fatty acid contents in milk, resulting in a product of better quality for the human health.

Thermal and quality evaluation of vegetable oils used in ruminant feed

Dairies add fat supplements to the diets of small ruminants to increase energy production and consequently the production and quality nutritional and sensorial of the milk. This study investigated the thermal and oxidative stability of babassu, castor, faveleira, and sesame oils by TG/DTA and PDSC. The profile of the fatty oils studied was determined by GC–MS as well as physicochemical characteristics. The thermogravimetric profile of the oils indicated that mass loss was caused by the decomposition or volatility of the triacylglycerides. Faveleira and sesame oils showed a high percentage of polyunsaturated fatty acids, especially C18:2. From a nutritional standpoint, unsaturated oils are more suitable supplements for animals because they promote biochemical changes beneficial to human health.

Milk adulteration: Detection of bovine milk in bulk goat milk produced by smallholders in northeastern Brazil by a duplex PCR assay.

The aim of this study was to investigate the adulteration of goat milk produced by smallholders in semiarid northeastern Brazil with bovine milk as an adulterant. The study was requested by the association of smallholder producers in the region to investigate and to inhibit adulteration practices as a need to ensure the quality and safety of goat milk. A duplex PCR assay has been developed and standardized. Further validation was performed in 160 fresh bulk goat milk samples. The detection limit of the duplex PCR was 0.5% bovine milk in goat milk and the results indicated that 41.2% of the goat milk presented to market was positive for bovine milk. Making the test available to the association of producers, together with extension activities, have been applied to reduce adulteration in goat milk sold to small-scale dairy plants and to ensure the species origin for goat milk in the state of Paraíba.

Development and quality of a Brazilian semi-hard goat cheese (coalho) with added probiotic lactic acid bacteria.

The effects of the addition of different strains of lactic acid bacteria on different quality parameters of a Brazilian goat semi-hard cheese (coalho) were assessed during 7 days of storage (10°C) as follows: Control, Lactobacillus lactis subsp. lactis and L. lactis subsp. cremoris (standard); C2, L. acidophilus; C3, L. paracasei; C4, Bifidobacterium lactis; and C5, L. acidophilus, L. paracasei and B. lactis. There were no differences for the proteolysis index and depth of proteolysis among the assessed cheeses. The cheeses presented increase in hardness, gumminess and chewiness during the storage. Regarding the ability to melt, all evaluated cheeses showed a reduction in diameter. Cheeses presented high luminosity with predominance of the yellow component; and number of lactic bacteria greater than 106–107 cfu/g during the 7 days of storage. C5 had better sensory scores in the acceptance test, purchase intention and preference ranking test. Coalho goat cheese could be a potential carrier of probiotic lactic acid bacteria.