Determination of folate in infant formula and adult/pediatric nutritional formula by optical biosensor assay: First Action 2011.05

After a review of data from a single-laboratory validation (SLV) study published in the International Dairy Journal 21, 783-789 (2011), a method for folate in infant formula and adult/pediatric nutritional formula was submitted for consideration of adoption by AOAC as an automated assay that is rapid and simple. The method uses an optical biosensor assay to quantitate total folate content in milk and milk-based pediatric and adult nutritional products. The assay uses folate binding protein and a functionalized sensor surface. The SLV showed an instrumental LOD of 0.1 ng/mL (equivalent to 2.5 microg/100 g for a typical infant formula). The method detection limit was 6.5 microg/100 g with a repeatability of 3.48% and an intermediate reproducibility of 4.63% RSD.

Successful development of satiety enhancing food products: towards a multidisciplinary agenda of research challenges

In the context of increasing prevalence of overweight and obesity in societies worldwide, enhancing the satiating capacity of foods may help people control their energy intake and weight. This requires an integrated approach between various food-related disciplines. By structuring this approach around the new product development process, this paper aims to present the contours of such an integrative approach by going through the current state of the art around satiety enhancing foods. It portrays actual food choice as the end result of a complex interaction between internal satiety signals, other food benefits, and environmental cues. Three interrelated routes to satiating enhancement are to change the food composition to develop stronger physiological satiation and satiety signals, anticipate and build on smart external stimuli at the moment of purchase and consumption, and improve palatability and acceptance of satiety enhanced foods. Key research challenges in achieving these routes in the field of nutrition, food technology, consumer, marketing, and communication are outlined.

[Determination of the content of eight metal elements in enteral nutritional powder (VIVONEX) by microwave digestion-AAS]

Enteral nutritional powder (VIVONEX) is mainly used to provide nourishment for critical patients and those patients who have just undergone surgical operation. Microelements included in it exert significant influence on the patients' physical functioning. In the present paper, Enteral nutritional powder was digested with HNO3 by microwave digestion. After that, the content of eight metal elements in it, K, Na, Ca, Mg, Fe, Mn, Cu and Zn, was determined by FAAS. With the good linear correlations of standard curves (r = 0.999 2-0.999 8), the recovery (n = 6) ranging from 97% to 103%, and the RSD (n = 6) from 0.46% to 1.12%, the method can be applied to simultaneous determination of several metal elements in enteral nutritional powder, and offers advantages of low detection limit, high sensitivity, speediness and accuracy. The determination of metal elements in samples by this method gives satisfactory results. Hence, the method helps to guarantee quality control of this kind of medicine, and supplies statistical evidence for the safety of clinical drug use.

Rheological properties and permeability of soy protein-stabilised emulsion gels made by acidification with glucono-δ-lactone

BACKGROUND

Soy protein, an important efficient emulsifier, is widely used by the food industry for incorporation into milk, yogurts, ice cream, salad dressings, dessert products, etc. The objective of this study was to investigate the rheological and physical properties of soy protein-stabilised emulsion gels as affected by protein concentration and gelation temperature.

RESULTS

The rheological properties and permeability were determined using oscillatory rheometry, permeability and whey separation. The modulus (G' and G″), fracture stress and fracture strain of acid-induced emulsion gels after 20 h of glucono-δ-lactone addition depended strongly on soy protein concentration and gelation temperature. At increasing soy protein concentrations, acid-induced emulsion gels had shorter gelation times but higher storage moduli (G'), fracture stresses and strains. Increasing gelation temperature decreased the gelation time, G', fracture stresses and strains. Permeability and whey separation were significantly affected by the protein concentration and the gelation temperature. A significant positive correlation was observed between whey separation and permeability coefficient in emulsion gels formed at different temperatures.

CONCLUSION

The rheological properties and permeability of soy protein-stabilised emulsion gels were significantly influenced by protein concentration and gelation temperature.

Atomic force microscopy as a nanoscience tool in rational food design

Atomic force microscopy (AFM) is a nanoscience tool that has been used to provide new information on the molecular structure of food materials. As an imaging tool it has led to solutions to previously intractable problems in food science. This type of information can provide a basis for tailoring food structures to optimise functional behaviour. Such an approach will be illustrated by indicating how a basic understanding of the role of interfacial stability in complex foods systems can be extended to understand how such interfacial structures behave on digestion, and how this in turn suggests routes for the rational design of processed food structures to modify lipolysis and control fat intake. As a force transducer AFM can be used to probe interactions between food structures such as emulsion droplets at the colloidal level. This use of force spectroscopy will be illustrated through showing how it allows the effect of the structural modification of interfacial structures on colloidal interactions to be probed in model emulsion systems. Direct studies on interactions between colliding soft, deformable droplets reveal new types of interactions unique to deformable particles that can be exploited to manipulate the behaviour of processed or natural emulsion structures involved in digestion processes. Force spectroscopy can be adapted to probe specific intermolecular interactions, and this application of the technique will be illustrated through its use to test molecular hypotheses for the bioactivity of modified pectin molecules.

Effect of extrusion on the antioxidant capacity and color attributes of expanded extrudates prepared from purple potato and yellow pea flour mixes

Foods with antioxidant capacity provide protection against cardio-vascular, certain forms of cancers, and Alzheimer's diseases caused by oxidative damages and contribute health benefits. The effect of extrusion cooking on the antioxidant capacity and color attributes of extruded products prepared from 3 selected formulations of purple potato and yellow pea flours using a co-rotating twin screw extruder were studied. Expansion ratios of the extruded products varied from 3.93 to 4.75. The total antioxidant capacities (TAC) of the extruded products, using DPPH assay, were 3769 to 4116 μg trolox equivalent/g dry weight sample and not significantly different (P > 0.05) from their respective raw formulations. The total phenolic contents (TP) of the extruded products varied from 2088 to 3766 μg of gallic acid equivalent/g dry weight sample and retained 73% to 83% of the TP from the raw formulations after extrusion. The total anthocyanins contents (TA) in the extrudates were 0.116 to 0.228 mg of malvidin-3-glucosides/g dry weight sample. Compared with their raw formulations, significant losses (60% to 70%) of the TA in the extruded products occurred due to extrusion cooking. Browning indices and color attributes such as brightness, chroma, and hue angle agreed with degradation of anthocyanins in the extruded products. However, extrusion cooking retained antioxidant capacities of the raw formulations in the extruded products either in their natural forms or degraded products with radical scavenging activity. This study demonstrated the potential for the production of puffed extruded food products with the improved antioxidant content from colored potatoes and pulse formulations.

Simultaneous determination of chromium, selenium, and molybdenum in nutritional products by inductively coupled plasma/mass spectrometry: single-laboratory validation

An inductively coupled plasma/MS method was developed for the simultaneous determination of Cr, Se, and Mo in infant formulas and other nutritional products. All samples were digested using a closed vessel microwave oven system, together with Ni and Te internal standards. The practical quantitation limits for Cr, Se, and Mo were 0.4, 0.2, and 0.4 ng/mL, respectively; dilution factors were 250 for powders and 50 for liquids. The Cr, Se, and Mo concentrations in 10 nutritional products were within specification limits, and within-day and day-to-day (6 independent days) precision values were <5% RSD. For two control samples, the observed precision was < or = 2% RSD over 10 independent days. In three National Institute of Standards and Technology standard reference materials, Cr, Se, and Mo results were within the certified limits. The average sample spike recoveries for 10 nutritional products ranged from 93 to 107%. Robustness studies showed a minimal effect from concomitant easily ionized element concentrations. However, the choice of internal standard and matrix matching carbon content were critical to obtaining accurate Se results. All indications are that this method would be a suitable candidate as a global reference method for the determination of these trace elements in nutritional products.

Dose-dependent suppression of hunger by a specific alginate in a low-viscosity drink formulation

Addition of specific types of alginates to drinks can enhance postmeal suppression of hunger, by forming strong gastric gels in the presence of calcium. However, some recent studies have not demonstrated an effect of alginate/calcium on appetite, perhaps because the selected alginates do not produce sufficiently strong gels or because the alginates were not sufficiently hydrated when consumed. Therefore, the objective of the study was to test effects on appetite of a strongly gelling and fully hydrated alginate in an acceptable, low-viscosity drink formulation. In a balanced order crossover design, 23 volunteers consumed a meal replacement drink containing protein and calcium and either 0 (control), 0.6, or 0.8% of a specific high-guluronate alginate. Appetite (six self-report scales) was measured for 5 h postconsumption. Relevant physicochemical properties of the drinks were measured, i.e., product viscosity and strength of gel formed under simulated gastric conditions. Hunger was robustly reduced (20-30% lower area under the curve) with 0.8% alginate (P < 0.001, analysis of covariance), an effect consistent across all appetite scales. Most effects were also significant with 0.6% alginate, and a clear dose-response observed. Gastric gel strength was 1.8 and 3.8 N for the 0.6 and 0.8% alginate drinks, respectively, while product viscosity was acceptable (<0.5 Pa.s at 10 s(-1)). We conclude that strongly gastric-gelling alginates at relatively low concentrations in a low-viscosity drink formulation produced a robust reduction in hunger responses. This and other related studies indicate that the specific alginate source and product matrix critically impacts upon apparent efficacy.

Chemical stability study of vitamins thiamine, riboflavin, pyridoxine and ascorbic acid in parenteral nutrition for neonatal use

BACKGROUND

The objective of this work was to study the vitamins B1, B2, B6 and C stability in a pediatric formulation containing high amounts of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulfate, pediatric vitamins and trace elements under different conditions using developed and validated analytical methods.

METHODS

The study was carried out during 72 h with formulations packaged in recommended storage temperature (4°C) and 25°C, with and without photoprotection.

RESULTS

The results showed that the methodologies used for assessing the chemical stability of vitamins B1, B2, B6 and C in the formulation were selective, linear, precise and accurate. The vitamins could be considered stable in the formulation during the three days of study if stored at 4°C. When stored at 25°C vitamin C presented instability after 48 h.

CONCLUSION

The pediatric formulation containing high amount of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulphate, pediatric vitamins and trace elements packaged in bag-type trilaminate presented a shelf life of the 72 h, when maintained under refrigeration, between 2°C and 8°C. This shelf life was measured considering the vitamins studied. Further studies are needed including all the vitamins present in this formulation.

[Product development on the basis of cereal and leguminous flours to coeliac disease in children between 6-24 months; I: formulation and acceptability]

The revaluation of the Andean cultivations, quinua (Chenopodium quinua Willd) and lupin (Lupinus albus L.), to be used in nutritional mixtures, with traditional cereals like corn (Zea mays L.) and rice (Oryza sativa L.), originate mixtures without gluten which constitute a good alternative for the nutrition of children under 24 months that suffer from celiac disease, since they improve the quality of the protein, by essential amino acids compensation, and also impacts in the product's diversification strategy. In the present work, the percentage composition of each flour in the mixture was determined by means of Linear Programming by means of the Solver form from the Excel spreadsheet. Prolamines were determined in the quinua and lupin flours by the ELISA test and the HPLC technique was used in both products obtained called "sweet mix" and "dessert mix", to define the quantity of amino acids with the purpose of providing around the 15% of the proteins required in the day. The flour mixtures selected as optimum, sweet mix, suitable for the preparation of sweet pancakes, as well as for the dessert mix, that by addition of water or milk produce a semi solid dessert, were evaluated after three months of storage, being acceptable their microbiological, bromatological and sensorial requirements, corroborating the results with the good acceptance of the products, prepared from the formulated mixtures, by the children of two Day Care centers of the City of Antofagasta-Chile.

Whey and casein labeled with L-[1-13C]leucine and muscle protein synthesis: effect of resistance exercise and protein ingestion

Muscle protein turnover following resistance exercise and amino acid availability are relatively well described. By contrast, the beneficial effects of different sources of intact proteins in relation to exercise need further investigation. Our objective was to compare muscle anabolic responses to a single bolus intake of whey or casein after performance of heavy resistance exercise. Young male individuals were randomly assigned to participate in two protein trials (n = 9) or one control trial (n = 8). Infusion of l-[1-(13)C]leucine was carried out, and either whey, casein (0.3 g/kg lean body mass), or a noncaloric control drink was ingested immediately after exercise. l-[1-(13)C]leucine-labeled whey and casein were used while muscle protein synthesis (MPS) was assessed. Blood and muscle tissue samples were collected to measure systemic hormone and amino acid concentrations, tracer enrichments, and myofibrillar protein synthesis. Western blots were used to investigate the Akt signaling pathway. Plasma insulin and branched-chain amino acid concentrations increased to a greater extent after ingestion of whey compared with casein. Myofibrillar protein synthesis was equally increased 1-6 h postexercise after whey and casein intake, both of which were higher compared with control (P < 0.05). Phosphorylation of Akt and p70(S6K) was increased after exercise and protein intake (P < 0.05), but no differences were observed between the types of protein except for total 4E-BP1, which was higher after whey intake than after casein intake (P < 0.05). In conclusion, whey and casein intake immediately after resistance exercise results in an overall equal MPS response despite temporal differences in insulin and amino acid concentrations and 4E-BP1.

The immunomodulating enteral nutrition in malnourished surgical patients - a prospective, randomized, double-blind clinical trial

BACKGROUND & AIM

The immunomodulating nutrition was supposed to reduce the incidence of complications in surgical patients, but many authors have questioned its value recently. The aim of the study was to assess the impact of enteral immunonutrition in postoperative period.

METHODS

Between January 2003 and December 2009, 305 malnourished patients (123 F, 182 M, m. age 60.8) undergoing resection for pancreatic or gastric cancer, after preoperative 14 days of parenteral feeding, were randomized in double-blind manner to receive either postoperative immunomodulating enteral diet (IMEN) or standard oligopeptide diet (SEN). Outcome measures of the intend-to-treat analysis were: number and type of complications, length of hospitalization, mortality, and vital organ function.

RESULTS

Median postoperative hospital stay was 17.1 days in SEN and 13.1 days in IMEN group (p = 0.006). Infectious complications were observed in 60 patients (39.2%) in SEN and 43 (28.3%) in IMEN group (p = 0.04). Differences were also observed in overall morbidity (47.1 vs 33.5%, p = 0.01) and mortality (5.9 vs 1.3%, p = 0.03), but the ratio of surgical complications, organ function, and treatment tolerance did not differ.

CONCLUSIONS

The study proved that postoperative immunomodulating enteral nutrition should be the treatment of choice in malnourished surgical cancer patients. The Clinical Trials Database registry number: NCT00576940.

[The Spanish Home Enteral Nutrition registry of the year 2009: from the NADYA-SENPE group]

OBJECTIVE

To describe the Home Enteral Nutrition Characteristics (HEN) recorded by the group NADYA-SENPE during 2009.

MATERIAL AND METHOD

collection and analysis of the data voluntary recorded in the HEN registry from the NADYA-SENPE group from January 1st to December 31st.

RESULTS

6.540 HEN patients were registered, 5.11% more than the previous year and 6,649 episodes (3,135 in women, 47,93%) from 32 different hospitals. 6,238 of them (95,38%) were over 14 years. The mean age of the patients under 14 yr was 3,67 ± 2,86 and it was 72,10 ± 16,89 in those over 14 yr group. The base illness registered more frequently was the neurological disorders in 2,732 (41,77%) patients, followed by cancer patients in 1,838; 28,10%. The enteral access route was registered in 1,123 (17,17%) of the episodes, being more frequent the administration by nasogastric tube 562 (50,04%). The mean length of nutritional treatment by episode was 323 days (10,77 months). 606 episodes of HEN ended, being the principal reasons for discontinuing treatment the patient death in 295 (48,68%) occasions. The transition to oral feeding occurred in 219 (36,14%) cases. Patients maintained normal activity in 2162 (32,55%) HEN episodes and 2,468 (37,13%) cases were living "bed-couch". The level of dependence was "total" in 2,598 (39,07%) of the episodes recorded. The nutritional formula was provided by the hospital in 4,183 (62,91%) cases and by the reference pharmacy in 2,262 (el 34,02%). Consumables were provided by the hospital in 3,531 (53,11%) cases.

CONCLUSIONS

The number of HEN patients recorded increased from the year 2008, continuing the gradual growth increase since the start of registration. The characteristics of the patients remain in the same profile as in previous years.

[Simultaneous determination of five illegal drugs in weight control foods with solid phase extraction-high performance liquid chromatography]

OBJECTIVE

To develop a method for simultaneous determination of hydrochlorothiazide, furosemide, clopamide, bumetanide and sibutramine hydrochloride in weight control foods with solid phase extraction-high performance liquid chromatography.

METHODS

The analytes in the samples were extracted with 2% phosphoric acid-methanol (1:1, V/V) solution ultrasonically and centrifuged. The extracts were clean-up with Osis MCX SPE columns, concentrated under weak N2 stream, and reconstituted with 2% phosphoric acid-methanol (1:1, V/V) solution, vortex mixing and centrifugation at 12,000 r/min. The high performance liquid chromatography was performed with Phenomenex C18 (250 x 4.60 mm, 5 microm) as separation column, 0.02 mol/L acetonitrile potassium dihydrogen phosphate buffer as mobile phase, gradient elution of 1.0 mL/min for the flow rate, and 40 degrees C for the column temperature. The standard curve method was used for the quantitative analysis.

RESULTS

A good linear range appeared for the five analytes from 0.25 to 100 microg/mL (r > or = 0.999). The detection limits were 5.2-108 microg/kg. The average recoveries were 86.5%-113.1%, with the relative standard deviations of 1.6%-8.9%.

CONCLUSION

The proposed method is a reliable method with high selectivity and high sensitivity for the detection of the five illegal chemicals in the weight control foods.

Regulatory environment and claims - limits and opportunities

During the past decade, the use of claims became more and more important in many countries in relation to the increased awareness of consumer about the link between foods and health, offering to industry a valuable opportunity to differentiate and valorize their products and to promote innovation. However, more and more stringent regulations are developed, all based on the general principles adopted by the Codex Alimentarius Commission. In addition to the different regulatory processes and administrative requirements according to the country, the high level (and cost) of scientific substantiation of claims, the constraints introduced by nutrient profiles and the poor knowledge of the impact on consumer depending on the cultural contexts may limit these opportunities or, at least complicate their use. All these issues are briefly analyzed, highlighting some striking convergences and differences between countries.

Nutritional quality and osmolality of home-made enteral diets, and follow-up of growth of severely disabled children receiving home enteral nutrition therapy

This study evaluated the nutritional quality of home-made enteral diets and their effect on growth parameters. Thirty pediatric patients receiving only homemade enteral diets were enrolled. Samples of milk-based (MB) and soup-based (SP) feeds were taken for chemical analyses. The children's anthropometric indexes were assessed. In the MB, the measured values for the macronutrients and energy corresponded to approximately 70% of the prescribed values. Conversely, the SP measured values corresponded to less than 50% of the prescribed values, except for carbohydrate. The prevalence of underweight was 30% (9/30) at the time of entry into home nutritional therapy and declined to 20% (6/30) at the time of the study (p = 0.007). Stunting increased throughout the follow up, from 30% (9/30) to 53% (16/30; p = 0.511). Obesity prevalence fell from 17% (4/23) to 9% (2/23; p < 0.001). Despite their inconsistent levels of macronutrients and energy, home-made enteral diets had no negative effect on the patients' weights.

Determination of trans vitamin K1 in infant and medical nutritional products using AOAC Method 999.15 with modified preparation and extraction procedures and C30 bonded phase chromatography: single-laboratory validation

Modifications were made to AOAC Official Method 999.15 to extend its applicability to specialty infant formulas containing hydrolyzed proteins and free amino acids, and to medical and adult nutritional products. Minor changes to the sample preparation procedure and chromatographic separation improved vitamin K1 recoveries and reduced chromatographic interferences in these types of matrixes. Currently AOAC Method 999.15 is applicable only to the determination of total vitamin K1 (phylloquione) in infant formula and milk (fluid, ready-to-feed, and powdered) containing > 1 microg vitamin K1/100 g solids. AOAC Method 999.15 recoveries of vitamin K1 were improved by altering sample sizes, extraction solvents and amounts, and the reagent addition order and amount of water or aqueous solutions added. The chromatographic separation of vitamin K1 in medical nutritional products containing canola and marine oils was improved, and trans vitamin K1 was separated from the biologically inactive cis isomer in all products with a C30 3 microm column and a 100% methanol mobile phase. With these modifications to the extraction procedure and chromatographic separation, AOAC Method 999.15 demonstrated acceptable precision and accuracy for the quantitation of trans vitamin K1 in specialty infant formulas containing hydrolyzed proteins and free amino acids, and medical and adult nutritional products. A single-laboratory validation of these minor modifications was completed. Fourteen different product matrixes were analyzed during validation. The intermediate precision averaged 4.15% RSD (range 2.52-5.81% RSD), and recovery data averaged 100.1% (range 92.2-109%).

[Protocolisation of parenteral artificial nutrition: Methodological and organisational bases for process design and review]

In the field of parenteral artificial nutrition (PN) there is debate over the application of such concepts as standardisation, individualisation, protocolisation and normalisation. Artificial Nutrition Units (ANU) that are designing or reviewing their PN provision system must take into account the existing methodological and regulatory references as well as the resources available for implementing the process. The aim of this article is to review and evaluate the possibilities that exist for designing an efficient, safe process, applying the methodology of continuous quality improvement. Current requirements are reviewed in terms of quality of formulation, safety, and cost containment, as well as the resources available to avoid jeopardising the possibilities of adapting the treatment to suit patient needs or compromising its efficacy. The solution to the problem of whether the chosen approach in the system of PN provision is appropriate must come from review of the quality of service through the evaluation of indicators both of process and results. In this task, the hospital pharmacist plays a significant role as an agent in guaranteeing compliance with good practice guidelines.