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At least 19 recordsLinked to original sources

PubMed1977

[Studies on coffee and coffee substitutes. XIX. Dependence of the quantity of a highly polymeric galactomannan on the degree of extraction coffee-extracts (author's transl)].

In extracts of Columbia Arabica Coffee the content of galactomannan precipitable with alcaline copper solution decreases slowly up to an extraction yield of 43.6%; it decreases somewhat more rapidly with higher extraction yields. An extract of Angola Robusta Coffee showed opposite behaviour. In this case the content of galactomannan increased with the extraction yield, although not evenly. Calculated on the basis of roasted coffee solids the extract of the Arabica coffee had a rather limited range precipitable polysaccharide, the Robusta coffee in contrast with rated increased amounts of galactomannan. The different behaviour of the two coffee varieties may be due to mote or less strong binding of this high-polymer carbohydrate to the cell wall.

Cell Wall↗

PubMed1976

[Studies of coffee and coffee-substitute. XVIII. Dependence of the quantity and composition of a high polymer galactomannan on the coffee species and degree of roasting (authors transl)].

It is possible to determine quantitatively with satisfactory accuracy the galactomannan which is precipitated in coffee brew after addition of Fehling solution. The content of polysaccharides in the extracts increases with the degree of roasting. Galactomannan makes up 6.6 to 12.7% of the dry matter of the extracts and 1.8 to 4.4% of that of roast coffee. It consists mainly of mannan, to a much smaller degree of galactan. Often there are traces of glucan. The content of mannan increases with the degree of roasting while that of galactan decreases very rapidly.

Coffee↗

PubMed1990

Comparison of coffee intake and coffee-induced symptoms in patients with duodenal ulcer, nonulcer dyspepsia, and normal controls.

Coffee and decaffeinated coffee stimulate acid secretion. In addition, many patients experience dyspepsia after coffee ingestion. Therefore, coffee is often prohibited by physicians in patients with peptic diseases. However, the association between peptic disease and symptoms remains unclear. This study compares coffee intake and the induction of symptoms by coffee in patients with duodenal ulcer disease, nonulcer dyspepsia, and normal controls. We have studied the coffee drinking habits of 58 duodenal ulcer patients, 55 nonulcer dyspepsia patients, and 55 normal controls. The use of coffee on a daily basis was not significantly different between duodenal ulcer patients (64%) and controls (56%), or between nonulcer dyspepsia patients (55%) and controls. There was also no difference between the three groups in the use of decaffeinated coffee, the number of cups per day, the method of preparation, the length of time of coffee use, or any change in coffee intake in the previous year. The intake of tea, caffeinated carbonated beverages, and aspirin or nonsteroidal anti-inflammatory drugs was also similar in the three groups. The duodenal ulcer patients were more likely to be cigarette smokers (45%) than either the controls (16%) or the nonulcer dyspepsia patients (24%). Daily alcohol intake was not significantly different in the three groups. The prevalence of coffee induction of dyspeptic symptoms was similar in duodenal ulcer patients (29%) and controls (22%), but was much more common in nonulcer dyspepsia patients (53%) than in controls (22%), p = 0.0036. In conclusion, there was no difference in coffee intake between patients with duodenal ulcer, nonulcer dyspepsia, or normal controls. However, patients with nonulcer dyspepsia, but not duodenal ulcer, were more likely to experience dyspeptic symptoms after coffee ingestion.

Caffeine↗

PubMed1992

Wake up and smell the coffee. Caffeine, coffee, and the medical consequences.

Caffeine is a methylxanthine whose primary biologic effect is antagonism of the adenosine receptor. Its presence in coffee, tea, soda beverages, chocolate, and many prescription and over-the-counter drugs makes it the most commonly consumed stimulant drug. Initially caffeine increases blood pressure, plasma catecholamine levels, plasma renin activity, serum free fatty acid levels, urine production, and gastric acid secretion. Its long-term effects have been more difficult to substantiate. Most of the caffeine consumed in the United States is in coffee, which contains many other chemicals that may have other biologic actions. The consumption of coffee is a self-reinforcing behavior, and caffeine dependence and addiction are common. Coffee and caffeine intake have been linked to many illnesses, but definitive correlations have been difficult to substantiate. Initial trials showing coffee's association with coronary disease and myocardial infarction have been difficult to reproduce and have many confounding variables. Recent studies showing a larger effect over long follow-up periods and with heavy coffee consumption have again brought the question of the role of coffee in disease states to the fore. Caffeine in average dosages does not seem to increase the risk of arrhythmia. At present there is no convincing evidence that caffeine or coffee consumption increases the risk for any solid tumor. The intake of coffee and caffeine has clearly been decreasing in this country over the past two decades, largely brought about by the increasing health consciousness of Americans. Although there have been many studies that hint that the fears of increased disease with coffee drinking may be warranted, many questions have yet to be answered about the health effects of coffee and caffeine use.

Arrhythmias, Cardiac↗

PubMed1976

Coffee grounds. I. Effects of coffee grounds on ration digestibility and diuresis in cattle, on in vitro rumen fermentation, and on rat growth.

Holstein steers were used to compare rations in which coffee grounds replaced grain at rates of 0, 5, 10, or 20%. The coffee grounds analyzed (%) dry matter 91.1, protein 11.8, fat 23.1, fiber 42.5, ash .7, and caffeine .13. Digestibility coefficients for dry matter, crude protein, and energy decreased, and ether extract increased progressively as concentrations of coffee grounds in the ration were increased. There was a significant decrease in nitrogen retention and utilization when the rations contained 10 or 20% coffee grounds. Coffee grounds depressed feed intake, increased urinary output, and increased water intake (based on dry matter intake). Coffee grounds caused diuresis and renal, urethral, and bladder irritation. Adding coffee grounds up to 35% of the substrate did not depress rumen microbial fermentation, as measured by in vitro gas production. Weight gain of rats fed rations containing 22.5% untreated coffee grounds was reduced significantly. Water extraction removed some undersirable factors in coffee grounds for rats, and ether extraction removed most of them. Incremental additions of coffee oil (1, 3, or 5%) to the basal diet resulted in incremental decreases in rat weight gain.

Animal Feed↗

PubMed1976

[Coffee hulls and pulp. XII. Effect of storage of coffee pulp on its nutritive value for calves].

Coffee pulp, dehydrated and stored for 7, 13 and 17 months or ensiled for 4, 10 and 14 months, was studied in calves with a rapid growing rate. Storage of dehydrated coffee pulp did not affect its chemical composition, but ensiling reduced crude fiber and increased its nitrogen free extract content after 10 and 14 months. Three growth trials were carried out with Holstein calves averaging 95 kg in the first and second trials, and 130 kg in the third. Eighteen calves were used in the first trial and 24 in each of the other two. In each trial the animals were divided into three equal groups and randomly assigned to one of the following treatments: control, which contained 48% cottonseed hulls, and the other two, with 30% dehydrated coffee pulp or 30% ensiled coffee pulp. Basically, the difference between trials consisted in the time of storage or ensiling of coffee pulp. In all trials, weight gains of calves fed coffee pulp (1.00, 0.90 and 0.98 kg/day, and 1.06, 0.94 and 1.08 kg/day, respectively) were significantly lower (P less than 0.05) than the weight gains induced by the control ration (1.21, 1.08 and 1.19 kg/day). Feed intake was also lower, but feed conversion ratio was higher for those rations containing coffee pulp. Calf performance was better with ensiled than with deydrated coffee pulp, particularly in the third trial, where the differences in weight gains were significantly higher (P less than 0.05). It is concluded that storage time does not change nutritive value of coffee pulp; and the ensiling is an adequate process for storing pulp during coffee harvesting, and, possibly also, for improving its nutritive value.

Animal Feed↗

PubMed1975

[Investigation on coffee and coffee-substitutes. XVII. Behaviour of polysaccharide-complexes of robusta-coffee during roasting].

Two varieties of Coffea robusta of light, medium and dark roasting degree were investigated. The results were similar to those which were published earlier concerning Coffea arabica. One part of the mannane and galactane is destroyed. Another part, which exists originally as a constituent of the holocellulose, is made water soluble. Of this part, the mannane is found in the complex of water soluble polysaccharides, the galactane in the complex of galactoarabane.

Cellulose↗

PubMed1976

[Coffee pulp and hulls. XI. Chemical characteristics of silaged coffee pulp with Napier grass (Pennisetum purpurem) and corn plant (Zea mays)].

Various physical and chemical changes that occur during the process of preparation of coffee pulp silage with the addition of molasses and forage, were identified and measured quantitatively. Three types of silage were prepared in duplicate in laboratory concrete silos, 45 cm wide and 50 cm high. The silages contained the following components: coffee pulp (EPC), pulp and Napier grass (EPCN), and pulp with corn fodder (EPCM). On a fresh basis, the last two contained equal proportions of coffee pulp and forage. Around 16% molasses were aded to all silages. Time of ensiling was 132 to 141 days. In order to determine the physical changes, the silage was weighed at the start and end of the ensiling period; the pH was determined at the end of same, and the drained liquids were measured during the experimental period. To determine the chemical changes, analyses were carried out on the various components used and on the mixtures ensiled at the start and at the end of the experimental period. The pH of the silage was 4.5, 4.3, and 3.8, and the losses of dry matter 10.6, 25.2, and 33.3% for the three types of silages, respectively. These percentages suggest that a better fermentation took place in those silages containing forages. The better fermentation of EPCN over EPC was due to the Napier grass which provided greater amounts of chemical components susceptible of fermentation than those found in coffee pulp. The quality of EPCM was superior due not only to the presence of corn fodder, which produced an effect similar to that of Napier grass, but also due to the fact that the coffee pulp used in this case contained the greater concentrations of soluble carbohydrates and lower levels of lignin than the coffee pulp used alone or with Napier grass. As a result of the fermentation process, in all three types of silage a decrease in dry matter content, of cellular contents and soluble carbohydrates was observed, as well as an increase in cellular walls and its components, and of protein. The magnitude of these changes was found to be directly related to the losses in dry matter. From the results of this research, it was concluded that the addition of forage improves the chemical characteristics of silage prepared from coffee pulp.

Animal Feed↗

PubMed1977

[Effects of a coffee-antacid-mixture and a commercial coffee with regard to gastrin, pH and gastric secretion (author's transl)].

The influence of a coffee-antazid-mixture was investigated at 30 patients with diseases of the stomach (17 with duodenal ulcer, 6 with gastric ulcer and 7 with chronic gastritis) in comparison to a commercial coffee. The parameters measured were the gastric basal acid output, the continuous registration of the pH by an intragastric electrode and the serum gastrin concentration before and after the application of the tests substances. 75% of the patients with duodenal ulcer showed a positive effect by means of a greater elevation of the intragastric pH after application of the mixture in comparison to coffee. The effect was strongly correlated to the basal acid ouptput. In the group with gastric ulcer and that with duodenal ulcer under the influence of the mixture the pH after the initial rise decreased to less deeper values. There was a close relationship to the patterns of gastric ulcer as well with chronic gastritis there was an additional facourable effect on the symptoms of abdominal pain which occured after coffee and not after the mixture. The group with chronic gastritis showed no difference between the pure coffee and the coffee-antacid-mixture. A possible relationship of the products of coffee roasting and the adsorptive properties of the antacid is discussed.

Adult↗

PubMed1989

Contribution of coffee aroma constituents to the mutagenicity of coffee.

About 40 coffee aroma constituents belonging to the classes of dicarbonyls, sulphur-containing compounds, furfuryls, N-heterocyclics and others were systematically evaluated in three Ames tester strains. Only aliphatic dicarbonyl compounds showed notable direct mutagenic activity, which mainly affected 'base-pair substitution' in Ames tester strains TA100 and TA102. Very weak effects were also seen with some N-heterocyclics, mainly affecting frameshift tester strain TA98 upon metabolic activation. However, it was shown that these N-heterocyclics do not contribute substantially to the mutagenicity in coffee. The hydrogen peroxide and methylglyoxal contents of coffee were determined up to 26 hr after preparation. Their concentrations tended to decrease whereas mutagenic activity decreased significantly with time in tester strains TA100 and TA102. It is concluded that several highly labile coffee constituents contribute to the bacterial mutagenicity and also that the synergism between hydrogen peroxide and methylglyoxal is not the main factor. The absence of coffee mutagenicity/carcinogenicity in rodents with these highly reactive coffee aroma compounds can be explained in part by detoxification of microsomal enzyme systems.

Chromatography, Gas↗

PubMed1976

[The effect of coffee and coffee components on the stomach muscle].

The isolated stomach muscle strip preparation works well when given pure compounds which are stable and non-toxic. When complex test mixtures such as coffee are used, however, the results are more difficult to interpret. This is probably due to non-specific effects of such mixtures, e.g. induction of changes in organ bath pH, etc. In spite of the above remark, differences in the effects of decaffeinated and normal instant coffees were clearly seen. The so-called "wholesome" coffees gave results identical to those obtained with normal instant coffee. In general, coffee induced muscle contraction followed by relaxation. Choline (possibly together with potassium) would appear to be responsible for the contractions observed, and caffeine for the relaxation.

Animals↗

PubMed1978

The effects of de-caffeinated coffee versus whole coffee on hyperactive children.

The effects of whole coffee and de-caffeinated coffee on hyperactive children were compared, using a double-blind crossover design. Reactions were assessed by tests of concentration, digit recall, visuo-motor co-ordination, and parents' and teachers' rating scales. Whole coffee was associated with a significant improvement on all measures when compared with de-caffeinated coffee. The results suggest that whole coffee as part of the normal diet may be a useful first step in the treatment of hyperactive children.

Attention↗

PubMed1976