Determination of fat, protein and moisture in ricotta cheese by near infrared spectroscopy and multivariate calibration.

Near-infrared reflectance spectroscopy (NIRS) with partial least squares regression (PLSR) was used to determine levels of fat, protein and moisture in ricotta cheese without complex sample preparation. Spectra of 19 conventional and low-fat ricotta samples from different manufacturers were collected in duplicate, with 33 of the 38 spectra used as a calibration set and the remaining 5 spectra used as an external validation set. The best results were obtained by processing the spectral region between 1,100 and 2,500 nm. Multivariate models with six latent variables (LVs) showed good prediction capability for fat and protein determinations, with average relative errors (Er) of 6.37 % and 5.95 %, respectively. For moisture, a more robust model was obtained with 4 LVs, showing better prevision capacity and Er of 1.91 %.

Supplementation with the omega-3 docosahexaenoic acid: influence on the lipid composition and fatty acid profile of human milk / Suplementação com ácido graxo ômega-3 docosahexaenoico: influência sobre a composição lipídica e perfil de ácidos graxos no leite humano

OBJECTIVE: This study assessed the impact of supplementing the diet of women during pregnancy and lactation with fish oil containing the omega-3 fatty acid docosahexaenoic acid, and its influence on the composition of human milk. METHODS: The sample comprised 60 women aged 18 to 38 years with appropriate dietary pattern, all of them healthy and nonsmokers. The intervention consisted of a daily supplementation with fish oil capsules that corresponded to a daily intake of 315mg of docosahexaenoic acid and 80mg of eicosapentaenoic acid during the third trimester of pregnancy and the first three months postpartum. The total fat content and fatty acid profile of their milk were determined by creamatocrit and gas chromatography. Descriptive statistics were used for data analysis and the significance level was set at p<0.05. RESULTS: There was no statistical difference between the fat contents of the study (fish oil capsules) and control (capsules containing corn starch as filler) groups. However, the milk of women taking fish oil contained higher docosahexaenoic and eicosapentaenoic acid levels 30 and 60 days after delivery. These results demonstrate that high omega-3 intake can influence its concentration in human milk. CONCLUSIONS: Given the importance of docosahexaenoic acid in the neonatal period, it is appropriate for pregnant and breastfeeding women to supplement on long-chain polyunsaturated fatty acids, which may be done by adding fish oil to the regular diet.

OBJETIVO: Este estudo teve como objetivo avaliar o impacto da suplementação na dieta de gestantes e de lactantes com ácidos graxos ômega-3 docosahexaenoico, sob a forma de óleo de peixe, e sua influência na composição do leite humano. MÉTODOS: A amostra foi constituída de 60 gestantes, com idade entre 18 e 38 anos, saudáveis, com padrão alimentar adequado e não fumantes. A intervenção consistiu na suplementação da dieta com cápsulas de óleo de peixe, totalizando um consumo diário de 315mg de ácido docosahexaenoico e 80mg de ácido eicosapentaenoico, no período entre o terceiro trimestre de gravidez e o terceiro mês após o parto. O teor de lipídeos totais e do perfil de ácidos graxos foi determinado pelos métodos de crematócrito e de cromatografia gasosa. Para a análise dos dados foi utilizada estatística descritiva e nível de significância de p<0,05. RESULTADOS: Entre o grupo sujeito à dieta suplementada (cápsulas de óleo de peixe) e o grupo controle (cápsulas contendo amido de milho como excipiente), não se constatou diferença estatística quanto aos valores totais de lipídeos. Entretanto, no leite das mães do primeiro grupo, a suplementação com óleo de peixe mostrou teores mais elevados na concentração dos ácidos docosahexaenoico e eicosapentaenoico, nos tempos 30 e 60 dias, demonstrando que um maior consumo de ômega-3 pode influenciar na sua concentração no leite humano. CONCLUSÃO: Considerando a importância do ácido docosahexaenoico no período neonatal, é adequado incrementar com ácidos graxos poliinsaturados de cadeia longa a alimentação de gestantes e de lactantes, o que pode ocorrer pela suplementação da dieta com óleo de peixe.

Influence of fermentation with Hanseniaspora sp. yeast on the volatile profile of fermented apple.

This study aims to evaluate the aromatic profile of fermented apple, obtained by the action of strains of Hanseniaspora uvarum and Hanseniaspora guilliermondii using two methods of analysis: static headspace and solid phase microextraction (SPME). The results obtained confirm that the strains of the Hanseniaspora genus contributed positively to the aroma profile of fermented apple, producing considerable amounts of esters and higher alcohols. In comparing the methods of analysis of aromatic compounds using headspace and SPME, it was verified that by using the headspace method it was possible to capture amounts that were up to 16 times greater than the value of the volatile compounds obtained by SPME. However, when using SPME, 5 times more compounds were obtained than when using headspace. Even so, in the conditions of this study it was noted that headspace was more efficient in the extraction of the aromatics of fermented apple when taking into consideration the cost effectiveness of both methods.