Neila Silvia Pereira dos Santos Richards

Evaluation of bromine and iodine content of milk whey proteins combining digestion by microwave-induced combustion and ICP-MS determination.

The bromine and iodine content of whey protein concentrate (WPC), hydrolysate (WPH), and isolate (WPI) was evaluated combining microwave-induced combustion (MIC) digestion with inductively coupled plasma mass spectrometry (ICP-MS) determination. MIC digestion allowed the decomposition of up to 500 mg of samples using diluted NH4OH solution (25 mmol L(-1)) for absorption of analytes, assuring the compatibility with ICP-MS determination. Accuracy was evaluated using milk powder certified reference material (NIST 8435) with good agreements for Br and I (102% and 105%, respectively). For Br and I, the limit of quantification obtained by ICP-MS was 7 and 281 times lower in comparison with ion chromatography determination, respectively. Iodine could be enriched in whey protein production and up to 70% of the tolerable upper intake level was found, thus revealing the need to monitor it in whey proteins. On the other hand, the concentration of Br was below its acceptable daily intake.

Aceitação sensorial e caracterização de frozen yogurt de leite de cabra com adição de cultura probiótica e prebiótico

Goats milk is recommended for people afflicted with cow milk intolerance and gastro-intestinal disorders. frozen yogurt was elaborated with 1% prebiotic (inulin), 0.25% starter culture (Streptococcus thermophilus and Lactobacillus bulgaricus) and 0.25% probiotic culture (Bifidobacterium animalis and Lactobacillus acidophilus) to verify probiotic potential (after 7 and 120 days of storage), physical-chemical quality and sensorial acceptance. During storage viable cells were reduced, mainly probiotic bacteria. Nevertheless, the product showed probiotic potential because of B. animalis and L. acidophilus sum, which reached the minimum desirable until the end of storage. Values of total dry matter (26.6±0.2%), protein (3.0±0.3%), fat (2.6±0.1%), pH (5.5±0.01) and acid lactic (0.2±0.01%) were similar to those descript by other researches for the same product. Sensorial evaluation was realized by 50 untrained panelists, with a 7- point hedonic scale and intention to purchase. The product received good scores for global appearance, color, aroma and taste. Texture and residual taste had lower acceptance rates. The intent to purchase showed that 61% of panelists asserted to buy the product against 39%, who would not buy it. Accordingly, this research showed the feasibility of elaborating the goats milk frozen yogurt with addition of pre- and probiotics.

Emprego de soro de leite líquido na elaboração de mortadela

The objective of this paper was to verify the possibility of incorporating fluid whey in mortadela. The water employed in the elaboration of mortadela was replaced in the proportions of 50, 75 and 100% by fluid whey. Sensorial characteristics (color, odor, flavor and texture), pH, color, emulsion stability of mortadela were evaluated, as well as the percentage of fat and liquid released after thermal treatment of mortadela emulsion. The addition of fluid whey did not exert significant influence on the sensorial characteristics, pH, color, emulsion stability and liquid released after the thermal treatments in mortadela. Water substitutions of 75 and 100% by fluid whey in the elaboration of mortadela promoted a lower percentage of fat released after thermal treatment. Based on the obtained results it is clear that fluid whey can be used to substitute 100% of ice used in the elaboration of mortadela, thus avoiding that exceeding fluid whey be released in the environment.

Efeito do óleo de eucalipto (Corymbia citriodora) no controle do carrapato bovino

This research was aimed at evaluating in vitro and in vivo effects of eucalyptus (Corymbia citriodora) oil on cattle ticks (Rhipicephalus (Boophilus) microplus). Negative control group and eight concentrations of eucalyptus oil (0.5; 1; 2; 5; 10; 20; 50; 100%), were used on in vitro trials with engorged female ticks. The efficacy of control ticks was 0; 30.5; 75.5; 91; 100; 100; 100; 100 and 100%, respectively. At the in vivo trial eighteen Holstein cows were allocated to three groups (negative control, eucalyptus oil at 3.5% - level estimated by regression analysis, accounting for 95% efficacy of control ticks on in vitro trial and amitraz at 0.025%). Engorged female ticks were counted before (mean of days -3, -2, -1) and after treatment (1, 2, 3, 5, 7, 10, 14, 21 days). The efficacy control tick was 0; 96.4 and 69%, respectively, at 21 days after treatment. On the 1st and 2nd milked after treatments, physiologic variables were evaluate and milk samples were collected to evaluate organoleptic properties in milk and yoghurt (negative control x phytotherapic treatment). Similar results were found with sensorial acceptance test of milk and physiologic variables.

Enhancement of microbial oil production by alpha-linolenic acid producing Yarrowia lipolytica strains QU22 and QU137

Microbial oils enriched in essential polyunsaturated fatty acids can be used as nutritional complements. In order to improve the lipid yields and lipid profiles of 2 Yarrowia lipolytica strains, the effects of medium components and culture conditions were investigated using shake flasks. Under optimized conditions (cultivation for 3 days at 25oC and 150 rpm, using peptone as a nitrogen source and glucose as a carbon source), the biomass, lipid yield, and lipid content reached 6.75 g/L, 3.48 g/L, and 51.55% for Y. lipolytica QU22, and 6.85 g/L, 3.52 g/L, and 51.38% for Y. lipolytica QU137, respectively. Using a shaking speed of 150 rpm, unsaturated fatty acids constituted 87.96% (QU22) and 87.08% (QU137) of the total lipids produced by these strains, with 9.52 and 7.86% of alpha-linolenic acid, respectively. The strains are suitable candidates for fermentation processes involving essential polyunsaturated fatty acid (PUFA) production.

Propriedades de pasta de mesclas de farinha integral com farinha refinada usadas na produção de pães

In whole wheat bread production in Brazil blends of whole flour (WF) with refined flour (RF) are used, which differ in their composition. Thus, the objective of this study was to investigate the pasting properties of WF with RF blends. Samples with 100% of WF, 100% of RF (controls) and blends of WF with RF in the proportions of 20, 40, 60 and 80% were analyzed, in a RVA (Rapid Visco Analyzer) equipment. The samples pasting temperatures were similar. The peak viscosity decreased proportionally with the increase of WF in blends. Higher values of breakdown and holding strength were found in flour with high viscosity peak. Final viscosity and setback values decreased as the content of WF in blends increased. The pasting properties of WF with RF blends must be seen in a combined way, because they affect bread production and storage. The results also showed that RVA can be used to help in formulating WF/RF blends with certain pasting properties.

COMPARAÇÃO DE DIFERENTES MÉTODOS ANALÍTICOS PARA QUANTIFICAÇÃO DE LIPÍDIOS EM CREME DE RICOTA

The complexity of each sample makes impossible to describe only one method of analysis as the best, therefore, we should consider the advantages and disadvantages of each method and relate it with the sample. The aim of this study was identify the best method for lipids quantification in ricotta cream with a comparative study of three physico-chemical methods of analysis for lipids. The methods used were Soxhelt (hot extraction, using ether as solvent), Bligh; Dyer (cold extraction with chloroform, methanol and water) and Gerber (acid hydrolysis, using sulfuric acid and isoamyl alcohol). We evaluated the method in this study, among those mentioned, which would provide greater efficiency and reproducibility. The method of Gerber had the lowest performance among the methods tested, although not statistically differ from the Soxhlet method, the reproducibility of Gerber detract this type of method. The Soxhlet method showed better reproducibility of results, and values closer to those pre-determined for this sample. Bligh; Dyer method showed the highest yield of the lipid content of the sample, so the hot extraction methods (Soxhlet) and cold (Bligh; Dyer) are those that best show the lipid content of ricotta cream analyzed.

VIABILIDADE PROBIÓTICA DE QUEIJOS MINAS FRESCAL COM TEOR REDUZIDO DE LACTOSE Probiotic viability of Minas Fresh cheeses with reduced lactose content

O objetivo deste trabalho foi avaliar a viabilidade dos micro-organismos probioticos Lactobacillus acidophilus LA-5 e Bifidobacterium sp. BB-12 adicionados a diferentes formulacoes de queijo Minas Frescal com teor reduzido de lactose. Oito formulacoes de queijo Minas Frescal foram desenvolvidas, sendo denominadas T1 a T6 as adicionadas de 1% da cultura probiotica, com concentracoes de enzima lactase de 0,3g/L 0,6g/L e 0,9g/L e tempos de reacao de hidrolise de 12 e 24 horas, e as formulacoes controles T7 (sem lactase e 1% da cultura probiotica) e T8 (sem lactase e sem probiotico). Os queijos foram submetidos a analises microbiologicas de contagem dos micro-organismos probioticos semanalmente durante o periodo de armazenamento, bem como a analises fisico-quimicas de gordura, proteina, umidade, cinzas, gordura no extrato seco, acidez titulavel e pH. As reducoes dos teores de lactose dos queijos adicionados de lactase variaram de 73,14 a 93,23%. Apesar das contagens de Lactobacillus acidophilus (4,38+0,01 a 7,88 +0,07 log UFC.g-1) nao terem atingido o valores minimos de 10 6 UFC.g-1 em todos os dias de armazenamento dos queijos, a populacao de Bifidobacterium sp. (6,05+0,08 e 7,90+0,04 log UFC.g-1) manteve-se acima de 6,00 log UFC.g-1 para todas as formulacoes desenvolvidas, conferindo assim caracteristica probiotica aos queijos. Os resultados obtidos demonstram a possibilidade da incorporacao de bacterias probioticas em queijos com teor reduzido de lactose, sendo assim uma alternativa inovadora ao mercado de intolerantes a esse carboidrato

Adding palm oil to the diet of sheep alters fatty acids profile on yogurt: Benefits to consumers

The aim of this study was to modify the fatty acid profile of yogurt from sheep milk by the inclusion of different concentrations of palm oil into their diet. Thus, thirty-six sheep during lactation were separated in four groups with nine animals each, as described below: the group T0 (0%); the group T2 (inclusion of 2% of palm oil); the group T4 (inclusion of 4% of palm oil) and the group T6 (inclusion of 6% of palm oil). After 60 days of the supplementation, milk samples were collected and yogurt was produced, which was evaluated regarding the concentration of saturated fatty acids (SFA), monounsaturated fatty acids (MFA), and polyunsaturated fatty acids (PFA). A significant reduction (p<0.05) in most SFA and a significant increase (p<0.05) on MFA and PFA was observed in the yogurt of sheep supplemented with 4 and 6% of palm oil. Consequently, it is possible to conclude that palm oil supplementation exerts positive effects on yogurt, since it led to the reduction of undesirable fatty acids and increased fatty acids beneficial to human health.

Physico-chemical characterization of frozen sheep meat for a predetermined period

Aimed to evaluate the physicochemical stability of lamb meat stored in a freezer (18°C) for predetermined period. Sheep meat samples from the longissimus dorsi that were packaged and stored at -18 °C for predetermined intervals of time: 0, 90, 180, 270, 360, 450, 540 days. The specific analyzes were performed at the Department of Food Science and Technology, Federal University of Santa Maria. In relation to the evaluated parameters can be observed linear decrease pH, protein, fat, moisture and ash, and increasing linearly to lipid oxidation, thawing loss and protein exudate. The storage period alters the physico-chemical characteristics of sheep meat.