Practical and theoretica l aspects of acid-base reactions in benzene and other organic solvents al'e discussed . The synthesis of the indicators bromphtha lein magenta E and B (the ethyl and n-butyl esters of t etrabromopheno lph thale in ) an d of their t etraalkylammonium salts is descri bed. Qualitative and spectrophotometric data concern in g the color reactions of the indicators with primary, seconda ry, and t ertia ry a li phatic amines , s ubstituted guan idines, a nd other n itrogen bases in benz ene and other types of organic solvents are presen ted. An expla nati on off ered for the color phenom ena is also appli cable to ulfon ephthalcins and other indicators.Examples are given of the qu antitative m eas urement of the relative reactivity of bases with bromphthal ein magenta in benzene. Illust rations a re furnishe d of the app li cation of the ind icato rs to the quantitative estimation of acids and bases, to measu rem ents of the relative s trengt,h s of orga ni c acids, and to the differen tiation o f primary, secondary, and tertiary a liphatic a mines.During t he sp ectrophotometric inves t igations, it was necessar y to des ign new types of a bsorption cells s uitable fo r vo latile solvents a nd for th in laye rs of solu t ion. A desc ription of the e cells is given.

A large quantity of diet composite was collected from a day's menu used in one of the human metabolic studies at Beltsville Human Nutrition Research Center. This material, intended as a reference for the determination of nutrients in complex food mixtures, was processed to provide samples that are being characterized for a variety of nutrients. Our laboratory has determined sugars and starch and, in particular, monitored the stability of the individual sugars. The results from subsamples which were stored either wet or dry under different conditions (e.g., at room temperature, in a refrigerator, or in a freezer) for varying periods of time are reported. Starch was determined by an enzymatic procedure similar to the AACC Method 76-11. Two independent methods based on gas-liquid and high-performance liquid chromatographic techniques were used for the sugar determinations. Comparisons of the two methods and of sample preparation procedures prior to chromatographic analyses are discussed.

A wide selection of ready-to-eat breakfast cereals was analyzed for sugars with a gas-liquid chromatographic technique. Cereal products from General Foods, General Mills, Kellogg, Nabisco, Quaker Oats, and Ralston-Purina were purchased locally. Sugars found in the cereals varied from sucrose alone to any combinations of fructose, glucose, lactose, maltose, and sucrose. The amount of a given sugar ranged from <0.5% to >SOo/o of dry weight. Amounts of but not types of sugar varied from lot to lot; usually only slightly more than the analytical variations between replicates. The analytical data were verified on Several occasions by comparisons with data from a liquid chromatographic technique in our own laboratory, and in other laboratories by similar methods.

Fourteen granola cereals from seven different manufacturers were analyzed for sugars with a gas chromatographic technique that determines the type and amount of all the common food sugars. The total sugar content of the cereals ranged from 22-32% of dry weight. Sucrose was the predominant sugar, along with varying amounts of fructose and glucose. Several cereals also contained lactose. New sampling procedures have been developed for these heterogeneous mixtures.

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