The assay of non-fat milk solids by the determination of orotic acid in milk chocolate and in the milk

The Analyst ◽  
1972 ◽  
Vol 97 (1160) ◽  
pp. 866 ◽  
Author(s):  
R. J. Motz
Keyword(s):  
Orotic Acid ◽  
Milk Chocolate ◽  
Milk Solids

Determination of Orotic Acid by Liquid Chromatography as a Criterion for Calculating Nonfat Milk Solids in Milk Bread

1989 ◽  
Vol 72 (4) ◽  
pp. 627-631
Author(s):  
Lap V Bui
Keyword(s):  
Orotic Acid ◽  
Chromatographic Method ◽  
Colorimetric Method ◽  
Milk Powder ◽  
Skim Milk ◽  
Nonfat Milk ◽  
Liquid Chromatographic Method ◽  
Milk Solids ◽  
Liquid Chromatographic

Abstract A sensitive and reproducible isocratic liquid chromatographic method is described for the determination of orotic acid levels in skim milk powder and milk bread. The results are used to calculate the nonfat milk solids content in milk bread. Sample preparation is simple and rapid and produces an extract which, after passing through an on-line cleanup system, has a minimum adverse effect on the performance and life of the analytical column. Mean recoveries of 96-105% were obtained with coefficients of variation in the range 1.0-8.5% and a detection limit of 5 mg/kg. The liquid chromatographic method was more sensitive than the standard colorimetric method, while results obtained by both methods agreed closely.

Collaborative Study of a Joint AOAC-OICC (Office International du Cacao et du Chocolat) Method for the Determination of Alkalinity of Ash in Cacao Products

1975 ◽  
Vol 58 (1) ◽  
pp. 150-155
Author(s):  
Walter Rostagno
Keyword(s):  
Cocoa Butter ◽  
Collaborative Study ◽  
Uniform Method ◽  
Milk Chocolate ◽  
Aoac Method ◽  
Standard Deviations ◽  
Milk Solids

Abstract In order to develop a uniform method for the determination of alkalinity of soluble and insoluble ash, AOAC methods 13.005 and 13.006 and OICC method 4b/1952 were compared. Five samples were sent to 10 collaborators: A, high ash cocoa; B, low ash cocoa; C, breakfast chocolate containing 30% A and 70% sugar; D, plain chocolate containing 25% B, 45% sugar, and 30% cocoa butter; and E, milk chocolate containing 10% B, 28% milk solids, 40% sugar, and 22% cocoa butter. The following within-laboratory and between-laboratory standard deviations were obtained from analysis of the collaborative data for alkalinity in soluble ash: OICC—Samples A and B, 1.5116 and 3.4337; Samples C–E, 0.7285 and 1.0394; AOAC—Samples A and B, 1.2800 and 3.6996; Samples C–E, 0.2956 and 0.8001. Corresponding values for alkalinity in insoluble ash were: OICC—2.1753 and 3.6856, 0.5100 and 1.0029; AOAC—1.5652 and 5.5006, 0.3129 and 1.6501. On the basis of these results, a joint AOACOICC method, based on the determination of alkalinity in soluble ash by the AOAC method and the determination of alkalinity in insoluble ash by the OICC method, has been adopted as official first action.

342. A note on the density of full-cream milk solids

1946 ◽  
Vol 14 (3) ◽  
pp. 400-402 ◽  
Author(s):  
C. H. Lea ◽  
R. Gane
Keyword(s):  
Milk Powder ◽  
The Other ◽  
Displacement Method ◽  
Method Error ◽  
Headspace Gas ◽  
Entrapped Air ◽  
Liquid Displacement ◽  
Milk Solids ◽  
Spray Dried

A knowledge of the density of air-free milk solids is required for calculation of the quantity of oxygen originally enclosed in sealed cans containing milk powder, and for conversion of percentages of oxygen obtained by analysis of the headspace gas to absolute units. Determination of this figure is a matter of some difficulty owing to the presence of entrapped ‘air’ in the spray-dried product. In the liquid displacement method there is also a danger of error due to incomplete ‘wetting’ of the particles, or to solution of one or other constituent of the powder, while in the gas-displacement method error may be introduced by solution or adsorption of the gas by the powder. Lea, Moran & Smith(1) obtained values of 1·29 by a pyknometer method with ethylene glycol, and 1·31–1·32 by a nitrogen displacement method for full-cream solids containing 27% of fat. Muers & Anderson(2), on the other hand, reported values of 1·26–1·28 by a liquid-displacement method using propylalcohol. Further determinations have therefore been made by various modifications of all these methods.

Determination of molar enthalpy of sublimation in case of orotic acid as obtained from experimental and computational data

2018 ◽  
Vol 695 ◽  
pp. 107-111 ◽  
Author(s):  
Ilya I. Marochkin ◽  
Ekaterina P. Altova ◽  
Norbert S. Chilingarov ◽  
Anna L. Vilkova ◽  
Igor F. Shishkov
Keyword(s):  
Orotic Acid ◽  
Molar Enthalpy ◽  
Enthalpy Of Sublimation ◽  
Computational Data

XVII.—Utilization of Dietary Purines and Pyrimidines by Drosophila melanogaster

1957 ◽  
Vol 66 (4) ◽  
pp. 339-359 ◽  
Author(s):  
James H. Sang
Keyword(s):  
Drosophila Melanogaster ◽  
Orotic Acid ◽  
De Novo ◽  
Normal Growth ◽  
Energy Utilization ◽  
Good Growth ◽  
Response Curves ◽  
Adenylic Acid ◽  
Multicellular Organisms

SynopsisDrosophila melanogaster larvæ when cultured aseptically on a synthetic diet require exogenous ribose nucleic acid (RNA) for normal growth even though they can synthesize their own endogenous RNA from simple precursors. The optimum dietary supply lies between 0.4 and 0.7 per cent RNA. Individual bases, nucleosides and nucleotides which make up RNA cannot substitute for the whole polynucleotide, but adenine, adenosine, adenylic acid, guanosine and guanylic acid are used and stimulate growth to varying degrees. The pyrimidines and their nucleosides and nucleotides are not used when fed singly.It is shown that the de novo synthesis of purines may be more difficult than that of pyrimidines, and that if a source of purines is supplied (as adenylic acid), then the nucleosides and nucleotides of both cytosine and uracil are utilized by the larvæ, whereas the free bases are not. Cytidylic and uridylic acids seem to be interchangeable, and together with an adequate supply of adenylic acid give as good growth as RNA. Orotic acid and 2—6-diaminopurine are not used by the larvæ under the conditions described, but hypoxanthine and inosine are: xanthine and xanthosine can also be shown to have an effect on growth.Dose-response curves were determined for adenylic, guanylic, cytidylic and uridylic acids under conditions which allow the determination of the optimal supplies of each. These are found to be about 0.110, 0.080, 0.025 and 0.025 per cent, respectively. The requirement of RNA is therefore primarily a requirement of adenylic acid, since more than enough of the other nucleotides should be available when the supply of RNA is optimal. The optimal supply of adenine corresponds almost exactly with the optimal supply of adenylic acid, though a somewhat delayed larval development may be a result of energy utilization in the base-nucleoside-nucleotide conversion.These results are discussed in the light of our knowledge of purine and pyrimidine utilization in other multicellular organisms, particularly the rat, and possible applications of the findings are considered.

Ion chromatographic method for the determination of orotic acid in urine

2018 ◽  
Vol 563 ◽  
pp. 9-14 ◽  
Author(s):  
Orhan Destanoğlu ◽  
Damla Zeydanlı ◽  
Mehmet Şerif Cansever ◽  
Gülçin Gümüş Yılmaz
Keyword(s):  
Orotic Acid ◽  
Chromatographic Method
Sign in / Sign up

Export Citation Format

Share Document