Genome-wide association between single nucleotide polymorphisms with beef fatty acid profile in Nellore cattle using the single step procedure.

BACKGROUND: Saturated fatty acids can be detrimental to human health and have received considerable attention in recent years. Several studies using taurine breeds showed the existence of genetic variability and thus the possibility of genetic improvement of the fatty acid profile in beef. This study identified the regions of the genome associated with saturated, mono- and polyunsaturated fatty acids, and n-6 to n-3 ratios in the Longissimus thoracis of Nellore finished in feedlot, using the single-step method. RESULTS: The results showed that 115 windows explain more than 1 % of the additive genetic variance for the 22 studied fatty acids. Thirty-one genomic regions that explain more than 1 % of the additive genetic variance were observed for total saturated fatty acids, C12:0, C14:0, C16:0 and C18:0. Nineteen genomic regions, distributed in sixteen different chromosomes accounted for more than 1 % of the additive genetic variance for the monounsaturated fatty acids, such as the sum of monounsaturated fatty acids, C14:1 cis-9, C18:1 trans-11, C18:1 cis-9, and C18:1 trans-9. Forty genomic regions explained more than 1 % of the additive variance for the polyunsaturated fatty acids group, which are related to the total polyunsaturated fatty acids, C20:4 n-6, C18:2 cis-9 cis12 n-6, C18:3 n-3, C18:3 n-6, C22:6 n-3 and C20:3 n-6 cis-8 cis-11 cis-14. Twenty-one genomic regions accounted for more than 1 % of the genetic variance for the group of omega-3, omega-6 and the n-6:n-3 ratio. CONCLUSIONS: The identification of such regions and the respective candidate genes, such as ELOVL5, ESSRG, PCYT1A and genes of the ABC group (ABC5, ABC6 and ABC10), should contribute to form a genetic basis of the fatty acid profile of Nellore (Bos indicus) beef, contributing to better selection of the traits associated with improving human health.

Can Chocolate Be Classified as an Ultra-Processed Food? A Short Review on Processing and Health Aspects to Help Answer This Question.

Chocolate is a confectionery product whose consumption has increased, particularly dark chocolate. Chocolate is produced with varying amounts of cocoa liquor (CL), cocoa butter (CB) and cocoa powder (CP). The main chocolate types are dark, milk and white. Processing steps for chocolate production are described, and nutritional compositions examined for benefits and risks to health. Chocolate processing comprises steps at farm level, initial industrial processing for production of CL, CB and CP (common for all chocolate types) and mixing with other ingredients (like milk and sugar differing according to chocolate type) for industrial chocolate processing. All chocolate types present similar processing levels, and none involve chemical processing. Nutritional profiles of chocolate products differ according to composition, e.g., dark chocolate contains more CL, and so a higher antioxidant capacity. Chocolate is an energy-dense food rich in bioactive compounds (polyphenols, alkaloids, amino acids). Studies have demonstrated benefits of moderate consumption in reducing cardiovascular risk and oxidative and inflammatory burden, improving cognitive functions, maintaining diversity in gut microbiota, among others. In our view, chocolate should not be classified as an ultra-processed food because of simple processing steps, limited ingredients, and being an important part of a healthy diet when consumed in moderation.

Effects of n-3 and n-6 feeding sources on the quality and lipid oxidation of meat from feedlot-finished Bos indicus steers.

This study was conducted to evaluate the fatty acid profile, sensory properties and lipid oxidation of meat on retail display (RD) from Nellore steers (n = 96) fed diets containing soybean (SOY), sunflower (SUN), or linseed (LIN) oil or a control diet (CON). After slaughtering, samples of the Longissimus muscle were collected for sensory properties (1 day), fatty acid composition (1 day) and oxidation stability (3 days under RDC) evaluations. No differences in total lipids, cholesterol, TBARS, and total SFAs, MUFAs, PUFAs, and PUFA/SFA were observed. However, meat from animals fed vegetable oil had more CLA than that of the CON samples. The flavour, juiciness and overall acceptability were affected by the treatments (P < 0.05), but no consistent effect of a specific oil source was observed. Meat colour was not affected by diets or days under RD, and 7-ketocholesterol was not detected in any sample. The oil sources used in this work were not effective in consistently changing meat properties.

Validation of two methods for fatty acids analysis in eggs.

A comparative study between two methods (lipid extraction followed by saponification and methylation, and direct methylation) to determine the fatty acids in egg yolk was evaluated. Direct methylation of the samples resulted in lower fatty acid content and greater variation in the results than the lipid extraction followed by saponification and methylation. The low repeatability observed for the direct HCl methylation method was probably due to a less efficient extraction and conversion of the fatty acids into their methyl esters as compared to the same procedure starting with the lipid extract. As the lipid extraction followed by esterification method was shown to be more precise it was validated using powdered egg certified as reference material (RM 8415, NIST) and applied to samples of egg, egg enriched with polyunsaturated omega-3 fatty acids (n-3 PUFA), and commercial spray-dried whole egg powder.

HPLC method for quantification and characterization of cholesterol and its oxidation products in eggs.

A new method was developed for the simultaneous determination of cholesterol and its oxidation products in eggs, using HPLC with UV and refractive index (RI) detectors, and HPLC interfaced with atmospheric pressure chemical ionization coupled to MS (HPLC-APCI-MS). The best conditions for direct saponification of the sample and extraction of the non-saponifiable material were defined using complete factorial designs with central points. The method showed accuracy and precision with a detection limit between 0.002 and 0.079 microg/g. The oxides cholest-5-ene-3beta,20alpha-diol and cholest-5-ene-3beta,25-diol identified by HPLC-UV-RI were not confirmed by HPLC-APCI-MS.

Determinaçäo de colesterol em ovos: comparaçäo entre um método enzimático e um método por cromatografia líquida de alta eficiência / The determination of cholesteral in eggs: a comparison of an enzymatic method with that of high performance liquid chromatography

Os métodos enzimáticos apesar de serem baratos e simples são pouco utilizados na análise de colesterol em alimentos, uma vez que a enzima reage com qualquer esterol presente na amostra. Considerando que ovos possuem apenas colesterol, o objetivo deste trabalho foi otimizar um método por cromatografia líquida de alta eficiência (CLAE). Em ambos os métodos foi realizado saponificação direta das amostras e extração da matéria insaponificável com hexano. No método enzimático foi utilizado um kit (LABORLAB SA) e a absorbância foi determinada a 499 nm, 90 minutos após a reação. Na CLAE utilizou-se coluna C18, 100x4,6 mm x 4um (Chromolith, Merck), fase móvel acetonitrila:isopropanol (85:15) e fluxo de 2mL/min. Os métodos foram validados através de testes de recuperação, material de referência certificado de ovo em pó (SRM 1846,NIST) e receptibilidade. Os valores médios de colesterol nos ovos foram 1363 +- 47 e 1364 +- 40mg/100g de gema para o método enzimático e por CLAE, respectivamente, não havendo diferenças significativas (p>0,01) entre os resultados obtidos pelos dois métodos. Ambos os métodos podem ser utilizados com confiabilidade para determinação de colesterol em gema de ovos, sendo que o método enzimático possui vantagem de ser bem menos oneroso que o por CLAE. (AU)

Enzymatic methods are simple and of low-cost, but are nevertheless little used in thedetermination of cholesterol in foods as the enzyme reacts with any sterol, present in the sample. As eggsonly have cholesterol, the objective of this study was to optimize an enzymatic method for the determinationof cholesterol in eggs and compare it to a high performance liquid chromatography (HPLC) method. Forboth methods, the samples were saponified directly and the unsaponifiable matter extracted with hexane.For the enzymatic method, a test kit (LABORLAB S.A) was used and the absorbance read at 499 nm, 90minutes after the reaction. For HPLC, a C18, 100 x 4.6 mm x 4 µm (Chromolith, Merck) column was used,the solvent being acetonitrile:2-propanol (85:15 v/v) with a flow rate of 2 mL/min. The methods werevalidated according to recovery test, the use of egg standard reference material (SRM 1846, NIST), andrepeatability. The mean result for the enzymatic method was 1363 ± 47 and for HPLC 1364 ± 40 mg/100g of yolk. There were no significant differences (p>0.01) found between the results of the two methods.Both methods are reliable for use in the determination of cholesterol in yolk, the enzymatic method showingthe additional advantage of being cheaper than HPLC. (AU)