Standard test meal

The Lundh test also includes intestinal intubation and direct measurement of enzyme output in duodenal juice but uses a standardized test meal as a pancreatic stimulus. Because this test requires release of physiological regulatory mediators from the duodenal mucosa, it is less specific than the SC test and may render falsepositive results in intestinal diseases such as celiac sprue. 

Dose PEG Standard test meal(see Table VIII). 

Measurements of True Magnesium Absorption. Appearance of a single ingested isotope in the plasma or urine can not provide a quantitative estimate of fractional absorption of a mineral without concomitant measurement of Isotope exchange between the mineral in the plasma and other body compartments 2A). Table IV shows the levels of urinary Mg from an intravenous injection that accompanied an oral dose of 50 mg Mg. Radioactivity was determined in 15 ml urine with a relative S.D. of < 1% in composites collected at Intervals up to 24 hours, and with < 4% in the 24-48 h collection. The relative standard deviations for Mg measurements were consistently higher, reaching unacceptable levels in samples taken after 12 hours following the test meal. 

Wood meal is used for industrial explosives and also as an anticaking agent etc. It is q,uite cheap and does not disturb the colour of flames, and is used mainly for lance compositions, A standard test indicated less than ly moisture 6.5 8.5 cc/g apparent specific volume 7% of the meal passes 30 mesh less than lA% ashtThe Ind. Exp.S, J. Handbook of industrial explosives, p,215(1966)1. 

Different complete test meals containing proteins, carbohydrates and lipids have been tested for measuring digestive hpase secretions and hpolysis levels in the CI tract. Shak Iso (initially from Sopharga Laboratories, later from Nestle Chnical Nutrition, France) was used as a complete hquid test meal. A standard 375 mL... 

Fig. 10.6 Gastric and duodenal pH variations during test meals in humans. Mean values and standard deviations were estimated from...

The standard methods (26) of analysis for commercial lecithin, as embodied in the Official and Tentative Methods of the American Oil Chemists Society (AOCS), generally are used in the technical evaluation of lecithin (27). Eor example, the AOCS Ja 4-46 method determines the acetone-insoluble matter under the conditions of the test, free from sand, meal, and other petroleum ether-insoluble material. The phosphoHpids are included in the acetone-insoluble fraction. The substances insoluble in hexane are determined by method AOCS Ja 3-87. 

The term "standard" is not meant to denote a digestion procedure which should be routinely used to determine potentially available calcium. Since the number of foods tested so far is limited, it will be more useful to think of the "standard" procedure as a set of conditions to be used to see how well we understand food chemistry and calcium solubility in the gastrointestinal environment. It should be used for measuring the relative solubility of calcium from foods and meals, but mostly in the context of comparisons with in vivo results to define factors which require further study. 

A collaborative study for the determination of ethoxyquin in various meals and extruded pet foods was done under Schreier and Greene (134). Eleven laboratories took part in the study and determined ethoxyquin in acetonitrile extracts of ground samples using a column packed with C,8 octadecylsilane and a mixture of acetonitrile and ammonium acetate solution as a mobile phase. The method was tested for the analysis of 16 samples that contained ethoxyquin from 0.25 to 289 ppm. Repeatability standard deviations ranged from 0.08 to 3.2 ppm, and repeatabil-... 

In a study recently carried out in Hong Kong on disposable plastic containers for take-away meals the migration of styrene oligomers, heavy metals and the overall migration from plastic containers and, where present, their lids were determined into food simulants under different test conditions. Results showed that all the disposable plastic container samples met the safety standards for heavy metals and residual styrene monomers. Hence, with the proper use of disposable plastic containers, they would be unlikely to cause a food... 

For the tests described below use for acid extraction the residue in the alundum crucible from the water (or water-alcohol) extraction, as described in step 6 of "Standard Method No 32" Before proceeding with the extraction, test for the presence of starch in the above residue by placing a small portion in a 50-ml beaker, adding 10 ml of distd w and bringing it to a boil. Then cool and add a drop of iodine (1 in methanol) so In. Appearance of a blue color indicates the presence of starch Note A Rice hulls may give a faint starch test from small rice particles, and corn meal will give a positive test also. Determine the presence of these materials by examination of the sample to be extracted... 

Total volume of pancreatic juice, amount or concentration of bicarbonate, and activities of pancreatic enzymes are measured in duodenal contents. The enzyme most commonly measured is trypsin, but amylase, lipase, chy-motrypsin, and elastase may also be evaluated. The Lundh test consists of administering a standardized meal consisting of 5% protein, 6% fat, 15% carbohydrate, and 74% nonnutrient fiber. Advantages of the Lundh meal are that it provides a physiological stimulus to the pancreas and is simple to administer. However, administration of the meal prevents determination of the total enzyme and bicarbonate or secretory volume. Moreover, it provides inadequate or no stimu-... 

The C-mixed chain triglyceride test is designed as a test of intraluminal pancreatic lipase activity.The substrate for the test is 1,3-distearyl>2( carboxyl- C) octanoyl glycerol, which contains long chain fatty acids in positions 1 and 3 and the C-labeled medium chain fatty acid (octanoic acid) in position 2 (Figure 48-9). The labeled substrate is administered orally to fasting patients with a standard meal of toast and butter. Breath samples are collected over a 5-hour... 

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