Biohydrogenation and digestion of long chain fatty acids in steers fed on Lolium perenne bred for elevated levels of water-soluble carbohydrate

Grass is a rich source of alpha-linolenic acid (18: 3n-3) and in this study the effects on ruminal fatty acid metabolism of feeding beef steers zero-grazed Lolium perenne containing elevated levels of water-soluble carbohydrate (WSC) were investigated. Eight Hereford x Friesian steers were offered ad libitum access to one of two varieties of Lolium perenne, Ba11353, high WSC (HS) or AberElan, intermediate WSC ( experimental control) harvested at different times of the day ( 14: 00 and 10: 00 h, respectively) to accentuate WSC differentials. The grass was zero-grazed and fed for 21 days, after which the animals were offered ad libitum grass silage for 14 days to provide a covariate intake. The dry matter ( 202 vs. 167 g per kg fresh weight), WSC( 243 vs. 161 g per kg DM), total fatty acids (21.4 vs. 17.9 g per kg DM) and proportion of 18: 3n-3 (0.54 vs. 0.43) were greater and fibre content was lower ( 251 vs. 296 g ADF per kg DM) for HS compared with the control. DM intake and intake of total fatty acids and 18: 3n-3 was higher for HS (9.3 vs. 6.7 kg per d; 201 vs. 117 and 108.5 vs. 51.3 g per d, respectively). There was a trend ( P <0.1) for the flow of 18: 3n-3 at the duodenal to be higher on HS (8.5 vs. 5.7 g per d) but surprisingly there was no significant difference in the flows of 18: 0 or 18: 1 trans (58.5 vs. 48.8 and 11.1 vs. 9.1 g per d, respectively). This may be attributed to the net flows of fatty acids across the rumen ( duodenal flow - intake) which were positive on the control and negative on the HS. Biohydrogenation of 18: 2n-6 and 18: 3n-3 was not different between treatments and averaged 79.9 and 90.5%, respectively. Intestinal absorption as a proportion of duodenal flow of all the fatty acids were high ranging from 0.70 for 12: 0 to 0.96 for 18: 1 trans. In conclusion, treatment HS a Lolium perenne bred for elevated levels of WSC had higher total fatty acids and a higher proportion of the beneficial fatty acid 18: 3n-3 compared to a control. The higher DM intakes achieved when feeding the treatment HS along with the greater content of 18: 3n-3 resulted in a trend for greater intakes of this fatty acid and flow to and absorption from the small intestine

Variability in the contents of pork meat nutrients and how it may affect food composition databases

Pork meat is generally recognised as a food with relevant nutritional properties because of its content in high biological value proteins, group B vitamins, minerals especially heme iron, trace elements and other bioactive compounds. But pork meat also contributes to the intake of fat, saturated fatty acids, cholesterol, and other substances that, in inappropriate amounts, may result in negative physiologically effects. However, there are relevant factors affecting the content of many of these substances and somehow such variability should be taken into consideration. So, genetics, age and even type of muscle have a relevant influence on the amount of fat and the contents in heme iron. Also the composition in fatty acids of triacylglycerols is very sensitive to the contents of cereals in the feed; for instance, polyunsaturated fatty acids may range from 10% to 22% in pork meat. The content of other nutrients, like vitamins E and A, are also depending on the type of feed. Some bioactive substances like coenzyme Q10, taurine, glutamine, creatine, creatinine, carnosine and anserine show a large dependence on the type of muscle. This manuscript describes the main factors affecting the composition of pork meat nutrients and how these changes may affect the general food composition databases. (C) 2012 Elsevier Ltd. All rights reserved.Grant AGL2010-16305 from the Spanish Ministry of Science and Innovation (Madrid, Spain) and FEDER Funds and collaboration of Vaquero Foundation for R+D on Pork Meat (Madrid, Spain) are acknowledged. Grant PROMETEO/2012/001 from Generalitat Valenciana (Spain) is also acknowldeged. Work prepared within the Unidad Asociada IAD (UPV)-IATA (CSIC) framework.Reig Riera, MM.; Aristoy, M.; Toldra, F. (2013). Variability in the contents of pork meat nutrients and how it may affect food composition databases. Food Chemistry. 140(3):478-482. https://doi.org/10.1016/j.foodchem.2012.11.085S478482140

Identification of emulsifier potato peptides by bioinformatics: application to omega-3 delivery emulsions and release from potato industry side streams

We are grateful for the financial support from Innovation Fund Denmark (Grant nr: 7045-00021B, PROVIDE project). We also acknowledge K.M.C. amba (Brande, Denmark) and A.K.V. amba (Langholt, Denmark) for providing the potato samples used in this study.In this work, we developed a novel approach combining bioinformatics, testing of functionality and bottom-up proteomics to obtain peptide emulsifiers from potato side-streams. This is a significant advancement in the process to obtain emulsifier peptides and it is applicable to any type of protein. Our results indicated that structure at the interface is the major determining factor of the emulsifying activity of peptide emulsifiers. Fish oil-in-water emulsions with high physical stability were stabilized with peptides to be predicted to have facial amphiphilicity: (i) peptides with predominantly α-helix conformation at the interface and having 18–29 amino acids, and (ii) peptides with predominantly β-strand conformation at the interface and having 13–15 amino acids. In addition, high physically stable emulsions were obtained with peptides that were predicted to have axial hydrophobic/hydrophilic regions. Peptides containing the sequence FCLKVGV showed high in vitro antioxidant activity and led to emulsions with high oxidative stability. Peptide-level proteomics data and sequence analysis revealed the feasibility to obtain the potent emulsifier peptides found in this study (e.g. γ-1) by trypsin-based hydrolysis of different side streams in the potato industry.Innovation Fund Denmark 7045-00021