OLIGOSACCHARIDES IN GOAT MILK: STRUCTURE, HEALTH EFFECTS AND ISOLATION

Oligosaccharides have been widely recognized for their prebiotic and anti-infective properties. Among the different types of mammalian milk, the one of humans is the richest source of naturally derived oligosaccharides. However, their use as a basis for functional foods is hampered, due to their structural complexity, which in turn makes their re-synthesis extremely difficult. Thus, oligosaccharides from other sources have to be used. In this sense, goat milk constitutes a very appealing candidate, as it contains the highest amount of oligosaccharides among domestic animals, while goat milk oligosaccharides show significant similarities to human milk oligosaccharides from a structural point of view. Studies on goat milk oligosaccharides are scant, and more data is required in order to provide solid clinical evidence of their beneficial effects on humans. The aim of this review is to collect and present the main research findings on goat milk oligosaccharides structure, health effects and isolation

Using product driven process synthesis in the biorefinery

In this work, we propose the use of the product-driven process synthesis (PDPS) methodology for the product and process design stage in biorefinery. The aim of the biorefinery is to optimize the total use of the whole feedstock – with focus being on various products simultaneously – rather than to maximize the extraction yield of one single product. The challenge is therefore two-fold; first to identify the main compounds of interest, i.e. the products of the biorefinery, and second to design a process scheme that will allow for an optimal quantity and quality of the identified compounds. To illustrate how PDPS can be used in biorefinery a case study based on sugar beet leaves is described. The identification of the main compounds of interest is based on the functionalities that they can deliver in the final applications, rather than on their quantities in the feedstock. To design the process scheme for the extraction of the selected compounds, task networks, currently used for the extraction of the individual compounds of interest, are used after adaptations. These adaptations are done on the basis of the qualitative and/or quantitative changes that certain tasks – used for the extraction of one compound – may cause on another compound of interest. By using the sugar beet leaves biorefinery case, we show that the PDPS methodology can be a useful tool for structured decision making during the product and process design stage in biorefinery

Using product driven process synthesis in the biorefinery

\u3cp\u3eThe design of a biorefining process is challenging due to the high number of products that can be obtained from one feedstock, and the fact that some products can be negatively affected by processing conditions that are essential for other products. To facilitate this design, we propose the use of the product driven process synthesis methodology, with some adaptations. Four novel steps were introduced: (1) decomposition of the feedstock into its main compound classes, (2) identification of the potential uses of the compound classes found in the feedstock, based on the functionalities that they can deliver, (3) selection of the product-targets by evaluating their economic potential, and (4) identification of “critical tasks”, i.e., tasks that negatively affect the quantity and/or quality of each product during their separation. To illustrate how this new approach can be used in practice, a case study of a sugar beet leaves biorefinery is presented.\u3c/p\u3

Giving added value to products from biomass: the role of mathematical programming in the product-driven process synthesis framework

In the first years of the 2000’s the late professor Peter Bongers introduced together with his co-workers at Unilever a design methodology that could be applied in the development of new products and processes for structured food products; the product-driven process synthesis method (PDPS). The method was successfully employed in the following years, designing new products from different bio based sources. Although researchers used the method and even made improvements; the structural incorporation of mathematical programming tools has been lacking and this seems to be a crucial component for decision-making processes. In this contribution we will discuss the possibilities to extend the PDPS framework with several of these optimization tools

Anti-inflammatory effects of a special carbohydrate-whey protein cake after exhaustive cycling in humans

Intense exercise induces increased levels of pro-inflammatory and anti-inflammatory cytokines. Thus, the purpose of this study was to examine the effects of a special cake (consisting of carbohydrate to whey protein 3.5:1) vs. an isocaloric carbohydrate cake on inflammatory markers after exhaustive cycling in humans. Nine subjects received either the experimental or placebo cake in a counterbalanced fashion using a crossover, double-blind, repeated-measures design. They performed one trial involving a 2 h exercise on a cycle ergometer at 60-65% VO(2)max followed by a 4 h recovery and then a second trial involving an 1 h exercise at 60-65% VO(2)max which was increased at 95% VO(2)max. Blood samples were collected pre-exercise, 30 min and 4 h post-exercise, post-time Trial and 48 h post-time Trial. Cakes were consumed immediately post-exercise and every 1 h for the next 3 h. The results showed that consumption of the experimental cake reduced significantly (p < 0.05), 4 h post-exercise, the pro-inflammatory protein levels IL-6 and CRP compared to the control group by 50% and 46% respectively. Moreover, in the experimental cake group, the level of the anti-inflammatory cytokine IL-10 was higher by 118%, 4 h post-exercise, compared to the control group but not statistically significant. (C) 2013 Elsevier Ltd. All rights reserved

Effect of a special carbohydrate-protein cake on oxidative stress markers after exhaustive cycling in humans

Exercise has been associated with oxidative stress that is correlated with muscle fatigue and reduced exercise performance. The aim of this study was to examine the effects of a special cake (consisting of carbohydrate to whey protein 3.5:1) vs an isocaloric carbohydrate cake on biomarkers of oxidative stress in 9 males after exhaustive cycling. A randomized single-blind cross-over study was completed. They performed one trial involving a 2-h exercise on a cycle ergometer at 60-65% VO(2)max followed by a 4-h recovery and then a second trial involved an 1-h exercise at 60-65% VO(2)max which was increased at 95% VO(2)max (time trial). The subjects received 4 experimental or placebo cakes after the first trial (the first immediately after and then one every hour). Blood samples were collected at eight time intervals: pre-exercise, 30 min, 1.5 h and 4 h post-exercise, post time Trial, 1 h, 24 h and 48 h post time Trial. Thiobarbituric Acid Reactive Substances (TBARS), protein carbonyls, total antioxidant capacity (TAC), catalase and glutathione (GSH) were determined spectrophotometrically. The mean time to exhaustion did not differ upon cake consumption. Consumption of the special cake reduced TBARS significantly, but had no effect on other oxidative stress markers. (C) 2012 Elsevier Ltd. All rights reserved

Minced beef is more rapidly digested and absorbed than beef steak, resulting in greater postprandial protein retention in older men.

Background: Older individuals generally experience a reduced food-chewing efficiency. As a consequence, food texture may represent an important factor that modulates dietary protein digestion and absorption kinetics and the subsequent postprandial protein balance. Objective: We assessed the effect of meat texture on the dietary protein digestion rate, amino acid availability, and subsequent postprandial protein balance in vivo in older men. Design: Ten older men (mean +/- SEM age: 74 +/- 2 y) were randomly assigned to a crossover experiment that involved 2 treatments in which they consumed 135 g of specifically produced intrinsically L-[1-C-13]phenylalanine labeled beef, which was provided as beef steak or minced beef. Meat consumption was combined with continuous intravenous L-[ring-H-2(5)]phenylalanine and L-[ring-H-2(2)]tyrosine infusion to assess beef protein digestion and absorption kinetics as well as whole-body protein balance and skeletal muscle protein synthesis rates. Results: Meat protein derived phenylalanine appeared more rapidly in the circulation after minced beef than after beef steak consumption (P <0.05). Also, its availability in the circulation during the 6-h postprandial period was greater after minced beef than after beef steak consumption (61 +/- 3% compared with 49 +/- 3%, respectively; P <0.01). The whole-body protein balance was more positive after minced beef than after beef steak consumption (29 +/- 2 compared with 19 +/- 3 mu mol phenylalanine/kg, respectively; P <0.01). Skeletal muscle protein synthesis rates did not differ between treatments when assessed over a 6-h postprandial period. Conclusions: Minced beef is more rapidly digested and absorbed than beef steak, which results in increased amino acid availability and greater postprandial protein retention. However, this does not result in greater postprandial muscle protein synthesis rates

The muscle protein synthetic response to the combined ingestion of protein and carbohydrate is not impaired in healthy older men.

Aging is associated with a progressive decline in skeletal muscle mass. been hypothesized that an attenuated muscle protein synthetic response main anabolic stimuli may contribute to the age-related loss of muscle The aim of the present study was to compare the muscle protein synthetic following ingestion of a meal-like amount of dietary protein plus between healthy young and older men. Twelve young (21 +/- 1 years) and (75 +/- 1 years) men consumed 20 g of intrinsically L-[1-13C]phenylalanine-labeled protein with 40 g of carbohydrate. specifically produced intrinsically L-[1-13C]phenylalanine-labeled allowed us to assess the subsequent incorporation of casein-derived into muscle protein. Blood samples were collected at regular intervals, muscle biopsies obtained prior to and 2 and 6 h after protein plus ingestion. The acute post-prandial rise in plasma glucose and insulin concentrations was significantly greater in the older compared with the males. Plasma amino acid concentrations increased rapidly following ingestion in both groups. However, plasma leucine concentrations were significantly lower at t = 90 min in the older when compared with the (P 0.05). We conclude that the use of protein-derived amino acids for muscle protein synthesis is not impaired healthy older men following intake of protein plus carbohydrate

Leucine co-ingestion improves post-prandial muscle protein accretion in elderly men

Background & aims: It has been speculated that the amount of leucine in a meal largely determines the post-prandial muscle protein synthetic response to food intake. The present study investigates the impact of leucine co-ingestion on subsequent post-prandial muscle protein accretion following the ingestion of a single bolus of dietary protein in elderly males. Methods: Twenty-four elderly men (74.3 +/- 1.0 y) were randomly assigned to ingest 20 g intrinsically L-[1-C-13]phenylalanine-labeled casein protein with (PRO + LEU) or without (PRO) 2.5 g crystalline leucine. Ingestion of specifically produced intrinsically labeled protein allowed us to create a plasma phenylalanine enrichment pattern similar to the absorption pattern of phenylalanine from the ingested protein and assess the subsequent post-prandial incorporation of L-[1-C-13] phenylalanine into muscle protein. Results: Plasma amino acid concentrations increased rapidly following protein ingestion in both groups, with higher leucine concentrations observed in the PRO + LEU compared with the PRO group (P <0.01). Plasma L-[1-C-13]phenylalanine enrichments increased rapidly and to a similar extent in both groups following protein ingestion. Muscle protein-bound L-[1-C-13]phenylalanine enrichments were significantly greater after PRO + LEU when compared with PRO at 2 h (72%; 0.0078 +/- 0.0010 vs. 0.0046 +/- 0.00100 MPE, respectively; P <0.05) and 6 h (25%; 0.0232 +/- 0.0015 vs. 0.0185 +/- 0.0010 MPE, respectively; P <0.05) following protein ingestion. The latter translated into a greater muscle protein synthetic rate following PRO + LEU compared with PRO over the entire 6 h post-prandial period (22%; 0.049 +/- 0.003 vs. 0.040 +/- 0.003% h(-1), respectively; P <0.05). Conclusion: Leucine co-ingestion with a bolus of pure dietary protein further stimulates post-prandial muscle protein synthesis rates in elderly men