Nutrient analysis

Procedure B— (sensitive) Range 0.25-18 ng-at N/liter Procedure C Range 0.6-40 p-g-at N/liter 

Note Do not use readings in excess of a logarithm 1.2. If more adsorption is encountered change from sensitivity B- (sensitive) to B or from A to B- (sensitive). With Procedure C, dilute the samples on the turntable with an equal volume of distilled water if more than about 35 /tg-at N/liter is anticipated. 

Use filings of pure or 99% pure cadmium metal that have passed a 32-mesh sieve but are held on a 60-mesh sieve (co. 0.25-0.50 mm). This rather close sizing is very important for good columns. Rinse the filings once or twice with a little clean diethyl ether to remove grease and dirt. Allow the metal to air-dry and store in a 

Dissolve 20 g of copper sulphate pentahydrate in 100 ml of distilled water. Store in glass or plastic. 

Dissolve 340 g of analytical reagent quality ammonium chloride in 3900 ml of distilled water. Add 50 drops of BRIJ, a detergent supplied by the Technicon Instruments Corporation. 

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Food Processor iN Nutrient Analysis System, Version 3.04, ESHA Research, Salem, Oreg., 1990 C. D. Hunt, T. R. Shuler, and L. M. Mullen,/. Am. Diet Assoc. 91, 558 (1991). 

Biological Gross organic components (BOD,TOC) Dissolved oxygen Nutrients analysis (NH3, PO4, NO3) pH Priority pollutant analysis ORP... 

Nutrient analysis of stabilized rice bran and its derivatives indicates that it is a good source of protein, dietary fiber and carbohydrates, in addition to several valuable phytonutrients, antioxidants, vitamins and minerals (Table 17.1). SRB and its water-soluble and water-insoluble derivatives contain all the nutrients at different levels. They are gluten and lactose free and do not give rise to any food allergy. 

Wolf WR and Ihnat M (1984) Evaluation of available certified biological reference materials for inorganic nutrient analysis. In Wolf WR, ed. Biological Reference Materials, pp 89-105, John Wiley Sons. 

Wolf WR, Iyengar GC and Tanner JT (1990) Muted diet reference materials for nutrient analysis of foods preparation of SRM-1545 Total diet. Fresenius J Anal Chem 338 473-475. 

Reference Material Needs for Regulatory Nutrient Analysis 287... 

Loder TC, Gilbert PM (1976) Blank and salinity corrections for automated nutrient analysis of estuarine and sea waters. University of New Hampshire Contribution UNH-59-JR101 to Technicon International Congress December 13-15... 

Since certified reference materials for seawater nutrient analysis are currently unavailable, individual laboratories must prepare their own standard solutions for instrument calibration. Standard stock solutions are prepared at high concentrations (mM) so that they can be used for months without significant alterations in concentration. Working low-concentration standard solutions are unstable and need to be prepared daily by diluting stock solutions with distilled water or low-nutrient seawater. In this case, the accuracy of nutrient analysis at a given laboratory is highly dependent upon the accuracy of the daily preparation of the calibration solutions. 

Gomis, D.B. and Alonso, J.J.M. 1996. Analysis for organic acids. In Handbook of Food Analysis, Vol. 1, Physical Characterization and Nutrient Analysis (L.M.L. Nollet, ed.) pp. 715-743. Marcel Dekker, New York. 

J Van Camp, A Huyghebaert. Proteins. In LML Nollet, ed. Handbook of Food Analysis. Volume 1 Physical Characterization and Nutrient Analysis. New York Marcel Dekker, 1996, pp 277-310. 

MAFF 1999, Nutrient analysis of other milks and creams. In, Archive - food surveillance information sheets, Number 178 May 1999, U.K. Food Standards Agency. Available at http //archive.food.gov. uk/maff/archive/food/infsheet/1999/nol78/178milk.htm... 

Nutrient analysis in order to determine the fertilization needed in organic fruit production, it is important to test the soil for nutrients before planting. This provides information about nutrient deficiencies and can also indicate whether there are excessive levels of certain nutrients in the soil. The soil sample should be tested for the following nutrients before a new orchard is set up ... 

Tropical storms, typhoons, or hurricanes, depending on their strength and geographical context, often deliver torrential rains. Increased river flow during such high intensity, low frequency rainfall events can transport a major portion of annual river N load to coastal systems. Historically, there has been a paucity of data on such events due to their irregular and extreme nature and the generally manual nature of water sample collection for nutrient analyses. However, with the use of in situ automatic water samplers and nutrient analysis systems, data from such events can now more readily be captured. 

In general, nutrient analyses are done either manually or using an autoanalyzer. Space limits preclude the presentation of detailed protocols. An excellent general review of nutrient analysis as well as detailed method descriptions and protocols can be found in Grasshoff et al. (1999) and Sparks et al. (1996). 

One might note that food tables are not extremely accurate. The lev els of specific nutrients can vary by several-fold, depending on methods for storage and cooking of food, plant variety, breed of farm animal, minerals in the soil used to grow the plant fol, and method of nutrient analysis. 

Other Parameters Measured Simultaneously with Bioluminescence. Measurements of several other parameters were obtained from the seawater after it had traversed the bioluminescence detector. When working on station with the bathy-photometer, which was equipped with a pressure transducer, temperature and beam transmittance were measured at depth while seawater was pumped by the submersible pump at depth to shipboard with 110 m of 2.54-cm ID hose. Sea surface temperature was obtained continuously from a probe at the intake near the sea chest. The seawater, obtained from either the sea chest or the bathyphotometer, was pumped through a Turner Designs fluorometer to measure chlorophyll fluorescence, and past a pH probe (31) and a conductivity cell when available. Samples of seawater were frozen for subsequent nutrient analysis (NO , NH4OH, P04 , and NO2). Plankton filtrates from 20 to 100 L (depending on plankton abundance) of seawater were collected from a 100-L effluent tank fitted with plankton net collection cups of 20-fxm mesh porosity. The filtrate was split, filtered onto Whatman GF/C 4.25-cm filter discs, and frozen for subsequent carbon and nitrogen determinations. The other half of the sample was preserved in 5% buffered formaldehyde solution for taxonomic analysis. 

Simultaneous collections were made of water and suspended sediments by an Inter-Ocean pump sampling system, Niskin bottles with internal rubber closures, Niskin bottles with Teflon-coated coil springs, and newly designed Niskin bottles without internal closures. The samples were examined for contamination, particularly of trace metals. AU the sampling systems led to some metal contamination of the samples except the new Niskin bottles. However, each system was found acceptable for nutrient analysis. Because of its novel closure, the newly designed Niskin bottle is convenient for suspended material analysis. Samples may be filtered directly from the sampling bottle without contacting the atmosphere. 

Osman, M.A. Chemical and nutrient analysis of baobab (Adansonia digitata) frait and seed protein solubility. Plant Foods for Human Nutrition. 2004, 59, 29-33. 

As an example, I will use the determinations of DOC and DON, partly because the discussions are very recent and partly because they are very familiar to me. The question of the accuracy of measurements of DOC in seawater has been disputed at least since the publications of Putter [62] and Krogh [63] the early work has been reviewed at length in an earher pubhcation [64]. While a variety of wet oxidation methods [65] were proposed for marine samples, the use of persulfate [35] provided the first real approach to a standard method. Persulfate oxidation, however, hke all purely chemical oxidations, was a batch process, and not easily automated. A number of workers proposed photo oxidation using ultraviolet (UV) hght [66-70], and automated analytical systems which produced data almost in real time were soon constructed [71-73]. Commercial units soon appeared, but many of the units in the field were jerry-built, constructed out of parts scavenged from discarded autoanalyzers formerly used for nutrient analysis. 

COMPOSITIONAL AND NUTRIENT ANALYSIS OF DRUM DRIED VALENCIA WASHED ORANGE PULP AND AACC REFERENCE WHEAT BRAN (a.b)... 

Table 13.6 shows the nutrient analysis of a diet for MPKU that meets the goals defined in the case example. In some centers, patients are encouraged to count milligrams of phenylalanine. Another approach that would meet these goals is to instruct the patient to consume the medical food and free foods (low-protein foods, fruits, non-starchy vegetables, fats, and sugars). 

Supplement with sugar-free vitamins and minerals as indicated based on nutrient analysis. 

Colorimetric methods for the determination of DIP, nitrate, nitrite, ammonium, and silicate are well established, with both manual and automatic procedures well understood and able to provide adequate sensitivity for most purposes. These methods can readily be used at sea and in the future probably in situ. International intercalibration exercises have shown that many laboratories now have the analytical expertise to measure nutrient concentrations at ambient levels, but this is not true of all laboratories and the analysis still requires careful analytical procedures that recognize the importance of contamination control, blank correction, and the complications arising from the saltwater matrix. Although there have been a number of such intercalibration studies, there is no widely available standard reference material for nutrient analysis at present. 

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