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Both regular and decaffeinated coffees were found to have cholinomimetic actions when tested in urethane-anesthetized rats. These actions were distinct from those of caffeine and reversible by atropine. The bioactive fraction was purified from alcoholic extracts of instant decaffeinated coffee by liquid column chromatography and preparative TLC. The purified compound showed similar pharmacological actions as the starting material. Chromatographic behavior was further characterized by analytical TLC and HPLC. Chromatographic analyses of extracts of green coffee beans and roasted ground coffees showed that the cardioactive compound was only present in roasted coffees. Similar analyses of other commonly consumed beverages, including teas and cocoa, showed that this compound was not present in beverages besides coffee.

Jute fibers are treated with about 5-7% of a high boiling mineral oil fraction ("batching oil") to render them flexible for making fabrics. Foods transported in jute bags are contaminated by this batching oil. A method involving automated on-line LC-GC is described for determining these hydrocarbons in various foods. Complete transfer of the LC fraction to GC is presupposed for obtaining the required sensitivity. Results are given for nuts, coffee, cocoa products, and rice. Contamination ranged between about 5 and 500 ppm.

The main objective of this work is to develop a routine quality control method for pesticide residues in cocoa beans, using gas chromatography-mass spectrometry. The investigated pesticides, which are used to control pests in the growing of cacao, are: Acephate, Propoxur, HCH, Heptachlor, Fenitrothion, Pirimiphos-methyl, Aldrin, Dieldrin, pp'-DDE, op-DDE and DDT. Two extraction methods were tested. The first was based on strong attack by concentrated sulphuric acid and later extraction with n-hexane: the investigated residues were Acephate, HCH, Fenitrothion and DDT; recoveries were 68-95% and the detection limits 0.5-10 ppb. The second extraction method was based on the Universal Trace Residue Extractor (UNITREX), which consists of a distillation system for organophosphorus and organochlorine pesticides in fatty samples. The investigated residues were Heptachlor, Pirimiphos-methyl, Aldrin, Propoxur, Dieldrin, op-DDE and pp'-DDE; recoveries were 67-88% and the detection limits 1-10 ppb.

A collaborative study was carried out in 30 laboratories to validate improvements to the official final action hydrophobic grid membrane filter (HGMF) screening method for Salmonella in foods, 985.42, by comparing the performance of the improved HGMF method against that of the AOAC/BAM conventional culture method. Six products were included in the collaborative study: milk chocolate, raw deboned poultry meat, black pepper, soy flour, egg yolk powder, and nonfat dry milk. The raw deboned poultry meat was naturally contaminated with Salmonella, and the remaining 5 products were each inoculated in advance with low levels of individual Salmonella serotypes. The AOAC/BAM method produced 11 false negative results and the improved HGMF method produced 18 false negative results. The improved HGMF Salmonella method has been approved interim official first action for all foods to replace the HGMF official final action method, 985.42.

With the aid of a new chiral derivatizing reagent and a sensitive and specific assay using capillary gas chromatography/negative ion chemical ionization mass spectrometry, the proportions of R and S enantiomers of 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) in mammalian tissues and foods were studied. R- and S-1MeTIQ enantiomers derivatized with a chiral derivatizing reagent, perfluoro-2-propoxypropionylchloride, were clearly separated. The ratio of enantiomers was R/S = 0.24, 0.55 and 0.60 in wine, cocoa and mouse brain. S-1MeTIQ predominated in all samples. This result suggested that 1MeTIQ could be formed at least partially through an enzymatic mechanism.

The extent to which tea, cocoa and carob (foods rich in polyphenols) influence fecal nitrogen (N) excretion was investigated in rats. The studies took into account the methylxanthine contents of tea and cocoa as well as the poor digestibility of cocoa nitrogen. Balance measurements indicated that all three food sources significantly increased fecal nitrogen excretion relative to methylxanthine-matched control diets (p less than 0.01). In the case of cocoa, virtually all the increase could be attributed to the poor digestibility of cocoa protein itself (estimated to be only 28-30% of total N in cocoa powder). There appeared to be no other effects. With extracts of tea and carob, however, the increased excretion of N in feces resulted either from a decreased digestibility of other dietary protein, through interaction with their polyphenols, or from a stimulation of the excretion of endogenous (body) nitrogen. With respect to the latter possibility, a preliminary investigation with the stable isotope of nitrogen (15N) showed that tea produced a marked increase in the excretion of endogenous nitrogen. These studies, therefore, indicate that foods rich in polyphenols have varying effects on N excretion in feces and that, in the case of tea at least, the loss of endogenous nitrogen may be a major contributing factor.

A collaborative study was performed in 11 laboratories to validate a colorimetric DNA hybridization (DNAH) method for rapid detection of Salmonella in foods. The method was compared to the standard culture method for detection of Salmonella in nonfat dry milk, milk chocolate, soy isolate, dried whole egg, ground black pepper, and raw ground turkey. Samples inoculated with high (0.4-2 cells/g) and low (0.04-0.2 cells/g) levels of Salmonella and uninoculated control samples were included in each food group analyzed. There was no significant difference in the proportion of samples positive by DNAH and culture procedure for any of the 6 foods. The colorimetric DNA hybridization assay screening method has been adopted official first action as a rapid screening method for detection of Salmonella in all foods.

A liquid chromatographic (LC) method has been developed to determine the content of polydextrose, a water-soluble 1 calorie/g bulking agent, in food matrixes such as cookies, cakes, fruit spreads, and chocolate toppings. This analysis, which requires use of a blank matrix, provides a feasible means to control the manufacture of foods containing this additive and provides a component for the accurate determination of the caloric value of a particular food product. The method involves aqueous extraction of the polydextrose from the food matrix followed by separation on a carbohydrate analysis column. The LC system uses a mobile phase of 0.005M CaSO4.2H2O and a refractive index detector for quantitation. Polydextrose recoveries from the food matrixes varied from 91.5 to 100.9% with assay precision, expressed as coefficient of variation, ranging from 0.7 to 4.3%. Each error estimate was derived from 5 parallel determinations. The present methodology is precise and selective in contrast to the modified classical phenol-sulfuric acid colorimetric method for assaying carbohydrates, which had been used for polydextrose determination in food matrixes in the past. Because the coefficient of variation frequently exceeded 10%, replicate analyses were necessary to achieve quantitation.

Results of urine drug analyses for three racing greyhounds that tested positive for caffeine in this laboratory were contested by the animal trainer, who asserted that positives were achieved from deliberate chocolate feeding by a rival kennel. The metabolism and excretion of methylxanthines was examined by high-performance liquid chromatography of extracts of the urine of racing greyhounds force-fed either caffeine (No Doz) or chocolate (Hersheys chocolate drops). Samples from untreated animals served as controls. Study results showed that test animals fed chocolate could be very easily distinguished from those fed caffeine. While the former animals exhibited a prominent theobromine peak with trace amounts of caffeine and theophylline, the caffeine-treated animals gave a prominent caffeine peak with moderate theophylline levels and almost nondetectable theobromine amounts. When these results were compared with the results from the positive authentic racing animals, chocolate feeding was clearly ruled out as an alternative to caffeine administration.

Furan represent a class of compounds that have been reported in a wide variety of foods. Normally, they result from thermal decomposition reactions, and, as such, are important in foods. They also possess unique sensory properties and, thus, can significantly contribute to food flavor. This review shall attempt to summarize their food occurrences, organoleptic properties, and formation pathways.

A collaborative study was performed in 11 laboratories to validate a DNA hybridization (DNAH) procedure for detection of Salmonella in foods. The DNAH procedure was compared to the standard culture method for detection of Salmonella in 6 foods: ground pepper, soy flour, dry whole egg, milk chocolate, nonfat dry milk, and raw deboned turkey. With the exception of turkey which was naturally contaminated, uninoculated and inoculated samples of each food group were analyzed. Results for the DNAH method were significantly better than for the standard culture method at the 5% probability level for the detection of Salmonella in turkey. There was no significant difference between the methods for the other 5 foods. The method has been adopted official first action.

The fatty acid composition including trans fatty acids of 12 brands of nut-nougat creams were analyzed by capillary gas chromatography. The creams consisted mainly of sugar and partially hydrogenated vegetable oil. The lipid content, which was quantified gravimetrically, amounted to between 30 and 38.2% in the different brands. The fatty acid composition varied considerably between the different creams. Linoleic acid, the major polyunsaturated fatty acid (PUFA), ranged from 12 to 39%. Palmitic acid (16:0), which was the main fatty acid, varied from 9 to 27%. The total trans fatty acid content of the 12 creams ranged from 0.9 to 12.3%. Only two of the creams contained less than 1% of trans fatty acids; 18:1t was the trans fatty acid found in the greatest amounts, whereas 16:1t and 14:1t were only found in trace amounts. Three samples had amounts of 18:2tt, 18:2ct, and 18:2tc between 0.7 and 1.06%; only small amounts of linoleate isomers were detected in the other creams. Our results show that trans fatty acids are present in every brand of chocolate cream tested. Since the potential risk of arteriosclerosis and cancer resulting from the consumption of trans fatty acids is not yet clear, different ways of production should be used in order to eliminate them from the creams that are a preferred bread spread of infants and children.

The choice of cocoa beans as the experimental and sample material for study of the contamination with lead and cadmium was inspired by high Pb and Cd limits in foods made on its basis (cocoa powder, chocolate) as well as by the relatively high proportion of these foods in human nutrition. For Cd, the limits in food products are within the range of 0.01 mg X kg-1 (milk) to 1.0 mg X kg-1 (kidneys) whereas the limits for lead range between 0.1 mg X kg-1 (e.g. milk) and 10.0 mg X kg-1 (e.g. tea, yeast, crustaceans, molluscs). Limits for Pb and Cd in foods made on cocoa bean basis are given in Table 1.

Tea, coffee, carbonated and chocolate beverages were analyzed for caffeine, and results compared in terms of usual serving sizes. Significant differences in caffeine levels were found to result from the preparation method of coffee or brewing time of tea. It is possible for a cup of tea, instant coffee, or can of cola beverage to have similar caffeine content (55 to 65 mg.); however, the mean values per cup of black tea (28 to 46 mg.) are considerably lower than for brewed coffee (107 to 151 mg.). Caffeine is readily absorbed and can have pharmacologic effects on adults or on children who consume quantities of cola beverages or chocolate. Both preparation method and quantity of beverage consumed should be considered in taking dietary histories or estimating caffeine intake.

This review attempts to present and discuss the current status of oxazoles and oxazolines relative to foods. Special emphasis is placed on their occurrences in foods, sensory properties, isolation and synthesis techniques, and pathways of formation in foods and related model systems.

A gas-chromatographic procedure is outlined for the analysis of cocaine and cis- and trans-cinnamoylcocaines in coca leaves. The procedure was applied to the determination of these alkaloids in coca leaves collected from three different locations in Peru. The extraction of alkaloids from plant material was accomplished following the procedure we previously outlined. Recovery of cinnamoylcocaines was quantitative and the average coefficient of variation was 6.8%. Using androst-4-ene-3,17-dione as the internal standard, the correlation coefficient (r2) as determined from the calibration curve of trans-cinnamoylcocaine was 0.99 and the response factor 0.72. Observable differences in relative proportions of cis and trans isomers of cinnamoylcocaine were found among samples from different locations. In addition, the relative proportions of the total cinnamoylcocaine concentration to cocaine varied with sample origin. We have also examined coca extracts using a nitrogen detector and by gas chromatography--mass spectrometry. The nature and identity of other nitrogenous peaks in the chromatograms are also discussed.

A method is described for simultaneous extraction and quantitation of the amines 2-phenylethylamine, tele-methylhistamine, histamine, tryptamine, m- and p-tyramine, 3-methoxytyramine, 5-hydroxytryptamine, cadaverine, putrescine, spermidine and spermine. This method is based on extractive derivatization of the amines with a perfluoroacylating agent, pentafluorobenzoyl chloride, under basic aqueous conditions. Analysis was done on a gas chromatograph equipped with an electron-capture detector and a capillary column system. The procedure is relatively rapid and provides derivatives with good chromatographic properties. Its application to analysis of the above amines in cheese and chocolate products is described.

A method using liquid chromatography was developed for the analysis of cholesterol in milk chocolate products. The method involves saponification of the sample with methanolic KOH followed by extraction with ether. Potentially interfering components are eliminated through the use of a silica Sep-Pak cleanup step before injection. The nonaqueous reverse phase LC system consists of a C18 column and an isopropanol-hexane mobile phase with direct detection at 205 nm. Recoveries of 1, 3, and 5 mg cholesterol added to 1 g sample of milk chocolate were 88.6, 102.8, and 110.1%, respectively. Studies conducted with [4-14C]-cholesterol were undertaken to further document the accuracy of the method.

A collaborative study was performed in 15 laboratories to evaluate a modification of the enzyme immunoassay (EIA) method for detection of Salmonella in foods (46.B21-46.B29). The modified EIA requires 18-24 h pre-enrichment, 6-8 h selective enrichment, and 14-18 h M-broth post-enrichment prior to performing the assay, which requires 1-2 h. Total assay time is 40-52 h. The modified method was compared with the standard culture method for detection of Salmonella in 5 low-moisture foods: nonfat dry milk, milk chocolate, meat and bone meal, dry whole egg, and ground pepper. The modified method has been adopted official first action for use with low-moisture foods.

This chapter has compiled and evaluated the current information on the methylxanthine composition of cocoa and various chocolate foods and beverages, as well as the consumption pattern for these commodities. Although the earliest recorded reference to cacao was in 1502, it was not until 1876 that milk chocolate was invented, an event that formed the backbone of the chocolate industry today. The consumption of cocoa throughout the world has been influenced by a number of factors, and the period of peak consumption occurred during the early to mid-1960s when these factors were highly favorable. The greatest consumption of cocoa in metric tons over the past 10 yr has been in the United States, although the highest per capita consumer during this period was Switzerland. The African continent has been historically the primary producer of raw cocoa, with the Ivory Coast currently being the largest individual supplier. Limited marketing survey data is available for the consumption of methylxanthines in chocolate foods and beverages. In children and teenagers, the major dietary source of caffeine was found to be tea, followed by soft drinks and coffee, respectively. Although chocolate foods and beverages ranked the lowest of these dietary sources to provide caffeine, they do constitute the major source of dietary theobromine. Cacao is the major natural source of the xanthine base theobromine. Small amounts of caffeine are present in the bean along with trace amounts of theophylline. The methylxanthine content of beans varies with the varietal type, and is influenced by the fermentation process. Chocolate liquor is a semifinished product commonly called "baking" or "cooking" chocolate. The average theobromine and caffeine content of liquors has been reported at 1.2% and 0.21%, respectively. Cocoa powder, which is prepared after removal of the cocoa butter, contains about 1.9% theobromine and 0.21% caffeine. Chocolate beverages comprise the most widely studied category of chocolate products. Hot cocoa provides 62 mg/serving of theobromine and 4 mg/serving of caffeine when prepared from commercial instant mixes. Instant cold chocolate milk mixes supply an average of 58 mg/serving of theobromine and 5 mg/serving of caffeine. The methylxanthine content of chocolate foods has received only slight attention in the literature. The methylxanthine content of sweet chocolate ranges from 0.359 to 0.628% for theobromine and 0.017 to 0.125% for caffeine.(ABSTRACT TRUNCATED AT 400 WORDS)

The investigation in question deals with the iron contamination in cocoa and chocolate products. Semi finished goods as well as finished products were examined. An average of 29 mg/kg total iron (i.e. ionic + metallic iron) was found in cocoabeans. The iron content of cocoa shells was approximately 10 fold higher. The process of grinding roasted nibs to cocoa-mass (liquor) resulted in a noticeable increase of the quantity of iron to an average amount of 150 mg/kg mass. This process thus produced an increase of the iron content of approximately 75 to as much as 200%. The cocoa powders contained more iron (238 mg/kg) than the cocoa mass, which linked to a reduction of the fat content by pressing and by grinding of the presscake. The quantities of iron observed in commercial samples of cocoa powder from different countries did not show appreciable differences.

A headspace gas chromatographic (GC) method, which can be automated, has been developed for determination of methyl bromide. This method has been applied to wheat, flour, cocoa, and peanuts. Samples to be analyzed are placed in headspace sample vials, water is added, and the vials are sealed with Teflon-lined septa. After an appropriate equilibration time at 32 degrees C, the samples are analyzed within 10 h. A sample of the headspace is withdrawn and analyzed on a gas chromatograph equipped with an electron capture detector (ECD). Methyl bromide levels were quantitated by comparison of peak area with a standard. The standard was generated by adding a known amount of methyl bromide to a portion of the matrix being analyzed and which was known to be methyl bromide free. The detection limit of the method was 0.4 ppb. The coefficient of variation (CV) was 6.5% for wheat, 8.3% for flour, 3.3% for cocoa, and 11.6% for peanuts.

The physical and chemical constants of cocoa shell fat (a by-product resulted during the production of cocoa butter at chocolate factories) were almost identical with those of cocoa butter obtained from the same cocoa beans except for their high acid value. Shell fat contained more amount of phospholipid content (as cephalin) than cocoa butter. The lipid classes were almost the same in cocoa butter and shell fat, however, the latter contained an unidentified constituent which was not found in cocoa butter. The fatty acids were determined quantitatively by GLC, and the results showed that the predominant acids in cocoa butter were palmitic, and oleic. Less amounts of capric, myristic, palmitoleic and linoleic were found in cocoa butter, whereas more amounts of these acids were found in shell fat. Cocoa butter gave higher values of stearic and myristic acids than those of shell fat. Seventeen compounds were detected by GLC in the unsaponifiable matter of both cocoa butter and shell fat from which eight were identified as C30 hydrocarbon, C32 hydrocarbon, squalene, alpha-tocopherol, cholesterol, campsterol, stigmasterol and beta-sitosterol in the two samples. The sterols were determined quantitatively, and it was found that the predominant sterol in cocoa butter and shell fat was B-sitosterol. Cocoa butter contained higher values of stigmasterol than that of shell fat, which contained increasing values of campsterol, low values of cholesterol were found in both samples. Stability of cocoa butter and shell fat towards oxidative rancidity at 100 degrees C was the same (10.5 hrs).

Vitamin D in different fortified foods is determined by using liquid chromatography (LC). Sample preparation is described for fortified skim milk, infant formulas, chocolate drink powder, and diet food. The procedure involves 2 main steps: saponification of the sample followed by extraction, and quantitation by LC analysis. Depending on the sample matrix, additional steps are necessary, i.e., enzymatic digestion for hydrolyzing the starch in the sample and cartridge purification before LC injection. An isocratic system consisting of 0.5% water in methanol (v/v) on two 5 microns ODS Hypersil, 12 X 0.4 cm id columns is used. Recovery of vitamin D added to unfortified skim milk is 98%. The results of vitamin D determination in homogenized skim milk, fortified milk powder, fortified milk powder with soybean, chocolate drink powder, and sports diet food are given.

The nickel content of 260 samples from various types of foods available in the Netherlands was measured by means of flameless atomic absorption spectrometry. In most samples the nickel content was found to be less than 0.5 mg/kg. Two products contained considerably more nickel than all the other foodstuffs, viz. nuts and cacao products, in which nickel concentrations up to 5.1 and 9.8 mg/kg, respectively, were measured. Occasionally nickel contents above 1 mg/kg were found in margarine and sauces.

With a sensitive method residues of 0.2--0.6 ppm ECH are found in commercial and bendtop infusions of cocoa and 1.8--5.6 ppm ECH in chocolate. The balance is established with time between ECH and ethylene oxide (EO) in the boiling infusion and the distillate depending on time. It is found that the ECH concentration in the infusion is reduced in 15 min to 1/7 by evaporation alone. No reaction to EO or ethylene glycol or other metabolites is detectable. For the determination alkali is added to the sample, followed by distillation of any formed EO into dilute sulfuric acid, where ethylene glycol is oxidized to formaldehyd according to Malaprade. This is distilled off for further enrichment and determined according to Bremanis by photometry at 570 nm. The determination for limit was to 0.01 ppm, the standard deviation is s = 0.0034 ppm (N = 30), the yield 99.8%. The sensitivity may be increased tenfold by increasing sample size.

The enantiomers of salsolinol were completely separated as diastereoisomeric derivatives, after reaction with S-1-(1-naphthyl)ethyl isothiocyanate, by reversed-phase high-performance liquid chromatography and quantified by electrochemical detection. Good calibration curves were obtained for the quantification and determination of the enantiomeric composition of salsolinol in human urine. The sensitivity and specificity to the assay also permit the determination of the enantiomeric composition of salsolinol in food such as dried bananas and chocolate.

Eighteen water-soluble food dyes have been studied by chromatography on thin layers of anion-exchange (AG 1-X4, DEAE-cellulose, PAB-cellulose and chitosan) and cation-exchange (Dowex 50-X4, Rexyn 102 and humic acid) materials; layers of silanised silica gel impregnated with cationic or anionic detergent were also used. Fourteen of the dyes were separated, but the two orange and the two black dyes were not. Some applications of the techniques to commercial products are reported.

A procedure based on extraction, column chromatography and precipitation is described for the separation of ethylene oxide-1,2-14C fumigated coca-powder derivatives in 9 different groups. As it was found in wheat [1], the major portion of radioactivity lies in water extract; in coca-powder the major portion of radioactivity is also found in low molecular components.

Four duplicate samples of cocoa-containing materials, a practice sample, and standards were submitted to the collaborators for theobromine and caffeine analysis by HPLC. In the method the samples are defatted with petroleum ether, and dried. The fat-free residue is then extracted with water and an aliquot is injected into the chromatograph. Compounds are quantitated by comparison with internal or external standards, either by peak height or peak area. Results for all the analyses showed that few of the values were more than 2 standard deviations from the mean. The method has been adopted as official first action.

A combined sample preparation/extraction procedure is presented for pesticide residue analysis of oilseeds and related high fat-low moisture products. The procedure utilizes high-speed milling to prepare the sample and high-speed homogenization in the extraction step to achieve what is apparently quantitative isolation of both incurred residues and natural oils. A separate, simple, oil determination step allows findings to be reported on either the fat or whole product basis. Petroleum ether, ethyl ether-petroleum ether (1 + 1), and ethanol are used serially as the extractants. Usual fatty food cleanup procedures and multiresidue gas chromatographic detection techniques are utilized. The procedure presented in this paper is a refinement of earlier work which used a homogenizer both to grind and to extract samples of unground seeds and which demonstrated essentially complete extraction of endrin residues in soybeans and DDT residues in mustard seed. Identical samples analyzed by the currently recommended shakeout procedure, 29.012, gave recoveries of approximately 50% of the total residues. The procedure presented in this paper was satisfactorily tested on 13 different oilseed types and one sample of soda crackers. Oil content for these samples ranged from 5 to 69%.

Forty different brands of chocolate candies were purchased in a supermarket. The wrappers were removed and coded, and the candy was re-wrapped in aluminum foil until analyzed. More than 60 percent of the samples had a polyunsaturated/saturated (P/S) ratio of less than 0.10. Although the candies examined had a higher carbohydrate than fat content, fat frequently contributed more calories in the candies containing more than 25 percent fat (15 of the 40 brands studied).

This is the first report confirming the presence of 1,2,3,4-tetrahydroisoquinoline (TIQ) and 1-methyl-1,2,3,4-tetrahydroisoquinoline(1MeTIQ) in a number of foods with a high 2-phenylethylamine content. These compounds were determined by gas chromatography-mass spectrometry. This study also confirmed that 1MeTIQ and TIQ can cross the blood-brain barrier in rat. Thus, these compounds, suspected to have relation to parkinson's disease, may accumulate in the brain from food sources.