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PubMed1999

Accelerated coffee pulp composting.

The effect of two abundant, easily available and very low-cost agro-industrial organic residues, i.e., filter cake from the sugar industry and poultry litter, on the composting stabilization time of coffee pulp and on the quality of the produced compost, was evaluated. Piles of one cubic meter were built and monitored within the facilities of a coffee processing plant in the Coatepec region of the State of Veracruz, Mexico. Manual aeration was carried out once a week. A longer thermophilic period (28 days) and a much lower C/N ratio (in the range of 6.9-9.1) were observed in the piles containing the amendments, as compared to the control pile containing only coffee pulp (14 days and a C/N ratio of 14.4, respectively). The maximum assimilation rate of the reducing sugars was 1.6 g kg-1 d-1 (from 7.5 to 5.3%) during the first two weeks when accelerators were present in the proportion of 20% filter cake plus 20% poultry litter, while they accumulated at a rate of 1.2 g kg-1 d-1 (from 7.4 to 9.13%) during the same period in the control pile. The best combination of amendments was 30% filter cake with 20% poultry litter, resulting in a final nitrogen content as high as 4.81%. The second best combination was 20% filter cake with 10% poultry litter, resulting in a compost which also contained a high level of total nitrogen (4.54%). It was concluded that the use of these two residues enhanced the composting process of coffee pulp, promoting a shorter stabilization period and yielding a higher quality of compost.

Biodegradation, Environmental↗
PubMed1983

Coffee contains potent opiate receptor binding activity.

Opiate receptor-active peptide fragments (exorphins) have been identified recently in casein and gluten hydrolysates, and morphine has been found in bovine and human milk. To determine whether similar peptides or alkaloids occur in other foodstuffs, we have screened potential sources using a rat brain homogenate assay to detect opiate receptor activity. We report here that instant coffee powders from a variety of manufacturers compete with tritiated naloxone for binding to opiate receptors in the rat brain membrane preparations, with no significant difference between normal and decaffeinated coffee. The receptor binding activity resembles that seen with opiate antagonists, in that there was no change in the half-maximal effective dose (ED50) in the presence of 100 mM Na+; on bioassay, the activity was similarly shown to be antagonistic and specific for opiate-induced inhibition of twitch. Preliminary characterization of the activity reveals that it has a molecular weight (MW) in the range 1,000-3,500, is heat-stable, ether-extractable, not modified by enzymatic digestion with papain, and clearly separable from caffeine and morphine on TLC. As its concentration in an average cup of coffee is five times the ED50, these data suggest that drinking coffee may be followed by effects mediated via opiate receptors, as well as effects of caffeine.

Animals↗
PubMed2004

Plant biochemistry: a naturally decaffeinated arabica coffee.

The adverse side effects of caffeine have increased the market for decaffeinated coffee to about 10% of coffee consumption worldwide (http://www.ncausa.org), despite the loss of key flavour compounds in the industrial decaffeinating process. We have discovered a naturally decaffeinated Coffea arabica plant from Ethiopia, a species normally recognized for the high quality of its beans. It should be possible to transfer this trait to commercial varieties of arabica coffee plants by intraspecific hybridization--a process likely to be simpler than an interspecific hybridization strategy, which could require more than 30 years of breeding to fix the decaffeinated trait and would probably result in an inferior cup of coffee.

Breeding↗
PubMed1983

Caffeine metabolism and coffee-attributed sleep disturbances.

In six healthy subjects with a history of caffeine-induced wakefulness caffeine kinetics were compared to with those in six subjects not affected by caffeine. The data indicated that the former have a longer plasma t 1/2 (mean 7.4 and 4.2 hr) and slower plasma clearance (mean 1.2 and 1.7 ml . min-1 . kg-1) of caffeine. Plasma caffeine concentration at midnight, 8 hr after afternoon coffee, is higher in those with caffeine-attributed insomnia. Those reporting "coffee wakefulness" also tend to drink less coffee. We conclude that the rate of caffeine metabolism is a determinant of individual variation in the effect of drinking coffee on sleep.

Adult↗
PubMed1987

Coffee consumption and blood pressure: an Italian study.

The relation between habitual coffee consumption and blood pressure was studied in 500 Italian subjects, males and females, aged 18-62 years. After allowing for sex, age and weight, the pressure levels showed a significant decrease with increasing coffee consumption. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were respectively 130.4 +/- 1.8 (SE) mmHg and 81.5 +/- 1.1 mmHg for non-coffee drinkers, 129.4 +/- 1.4 and 82.2 +/- 0.9 mmHg for 1 cup per day, 128.4 +/- 0.8 and 81.4 +/- 0.5 mmHg for 2-3 cups per day, 124.9 +/- 1.1 and 78.8 +/- 0.7 mmHg for 4-6 cups per day, and 124.1 +/- 2.5 and 78.7 +/- 1.6 mmHg for more than 6 cups of coffee daily (analysis of covariance: SBP F = 3.46, 4 df, P less than 0.01; DBP F = 3.46, 4 df, P less than 0.01). Even after correcting pressure levels for habitual alcohol intake and cigarette smoking, we observed a mean reduction in SBP and DBP of 0.80 mmHg and 0.48 mmHg respectively per cup per day.

Adolescent↗
PubMed1999

Changes in cigarette smoking and coffee drinking after alcohol detoxification in alcoholics.

AIMS: To assess the changes in cigarette smoking and coffee drinking after alcohol detoxification in alcoholics. DESIGN: Evaluation at admission and an average 16 days following discharge. SETTING: Alcohol detoxification inpatient programme. PARTICIPANTS: Seventy-three alcohol dependent (DSM-III-R) inpatients. MEASUREMENTS: Average number of cigarettes and of cups of coffee per day; urine cotinine level. Smokers were classified as moderate on the basis of consuming fewer than 30 cigarettes per day at the time of admission; heavy smokers were those who smoked 30 cigarettes per day or more. FINDINGS: As a group, the smokers (N = 58) did not significantly change their cigarette consumption and there was no change in urine cotinine level. Heavy smokers (N = 34), however, significantly decreased their cigarette consumption, but urine cotinine was unchanged. Moderate smokers (N = 24) significantly increased their cigarette consumption but urine cotinine was not significantly changed. All patients--non-smokers, moderate and heavy smokers--significantly increased their coffee intake. CONCLUSIONS: The results suggest that heavy smokers may react to alcohol cues and thus reduce smoking activity when sober. Moderate smokers may increase their smoking rate to cope with alcohol abstinence. These changes appear only to reflect a behavioural adjustment, without modification of patients' nicotine-seeking. Alcoholics may increase their coffee intake to cope with alcohol abstinence.

Adult↗
PubMed2000

Joint heavy use of alcohol, cigarettes and coffee and the risk of suicide.

AIMS: To estimate the relationship between joint heavy use of alcohol, cigarettes and coffee, and the risk of suicide in a general population with high rate of suicide. DESIGN: Prospective cohort analyses. SETTING: Finland. PARTICIPANTS: Data from 36,689 adult (age range 25-64 years) men and women who participated in the population surveys between 1972 and 1992. MEASUREMENTS: The mortality of the cohort was monitored for a mean of 14.4 years, which yielded 169 suicides. Criteria for heavy use of each psychoactive substance were defined as follows: alcohol (> 120 g/week), cigarettes (> or = 21/day) and coffee (> or = seven cups/day). FINDINGS: About half the men and 80% of the women did not use any of the psychoactive substances heavily. Every third man and every fifth woman used one substance heavily, and the prevalence for those who exceeded criteria for joint heavy use of two substances was 9% for men and 1% for women. Joint heavy use of all three substances was rare. The adjusted relative risk of suicide increased linearly with increasing level of joint heavy use of alcohol, cigarettes and coffee. Among subjects with heavy use of one substance the risk was 1.55 (95% CI = 1.10, 2.18), with joint heavy use of two substances 2.22 (95% CI = 1.37, 3.61), and with joint heavy use of all three substances 3.99 (95% CI = 1.80, 8.84) compared with no heavy use. CONCLUSIONS: Clustering of the heavy use of alcohol, cigarettes and coffee could serve as a new marker for increased risk of suicide.

Adult↗
PubMed2000

Consumption of French-press coffee raises cholesteryl ester transfer protein activity levels before LDL cholesterol in normolipidaemic subjects.

OBJECTIVES: To determine the long-term effects of unfiltered coffee consumption on the activity levels of cholesteryl ester transfer protein (CETP), phospholipid transfer protein (PLTP) and lecithin:cholesterol acyltransferase (LCAT) and to assess a possible role of CETP activity levels in the rise in serum LDL cholesterol. SUBJECTS AND DESIGN: Forty-six healthy normolipidaemic subjects consumed 0.9 L of either French-press or filtered coffee for 24 weeks. Fasting blood samples were obtained after 0, 2, 12 and 24 weeks of intervention and after and 12 weeks of follow-up. MAIN OUTCOME MEASURES: Serum activity levels of CETP, PLTP and LCAT. RESULTS: Relative to baseline, French-press coffee significantly increased average CETP activity by 12% after 2 weeks, by 18% after 12 weeks, and by 9% after 24 weeks. PLTP activity was significantly increased by 10% after 12 and 24 weeks. LCAT activity was significantly decreased by 6% after 12 weeks and by 7% after 24 weeks. The increase in CETP clearly preceded the increase in LDL cholesterol, but not the increase in total triglycerides. However, consumption of French-press coffee caused a persistent rise in CETP activity, whereas the rise in serum triglycerides was transient. CONCLUSIONS: Consumption of cafestol and kahweol cause a long-term increase in CETP as well as PLTP activity; the increase in CETP activity may contribute to the rise in LDL cholesterol.

Adult↗
PubMed2001

Characterization of pectin lyase produced by an endophytic strain isolated from coffee cherries.

AIMS: The effect of endophytic bacterial activity on the quality of coffee beverage was studied. METHODS AND RESULTS: A survey of the micro-organisms in coffee cherries was performed before harvesting, and their growth on the main nutrients available in coffee cherries was determined in vitro. CONCLUSION: Many endophytic bacteria were isolated from surface-sterilized coffee cherries. One of the pectinolytic strains was physiologically and phenotypically characterized, and was tentatively identified by partial 16S rDNA sequencing as Paenibacillus amylolyticus. This endophytic strain produced an extracellular pectinase with maximal activity at 40 degrees C and pH 7.9, and was thermostable up to 45 degrees C. EDTA and metal ions had little effect on pectin lyase activity. Km and Vmax values were 4.6 mg ml(-1) and 94.0 10(-8) mol min(-1) ml(-1), respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: Pectin lyases have been found in fungi but rarely in bacteria, and this isolate is a promising tool for regulation studies of these enzymes.

Bacillaceae↗
PubMed2005

Coffee and caffeine consumption reduce the risk of elevated serum alanine aminotransferase activity in the United States.

BACKGROUND & AIMS: Based on experimental and epidemiologic studies, we investigated whether coffee and caffeine consumption reduced the risk of elevated alanine aminotransferase (ALT) activity in persons at high risk for liver injury in a national, population-based study. METHODS: Participants were 5944 adults in the Third US National Health and Nutrition Examination Survey, 1988-1994, with excessive alcohol consumption, viral hepatitis, iron overload, overweight, or impaired glucose metabolism. Liver injury was indicated by abnormal serum ALT activity (>43 U/L). RESULTS: Elevated ALT activity was found in 8.7% of this high-risk population. In unadjusted analysis, lower ALT activity was associated with increasing consumption of coffee ( P = .001) and caffeine ( P = .001). Multivariate logistic regression analyses showed that the risk of elevated ALT activity declined with increasing intake of coffee ( P for trend = .034) and caffeine ( P < .001). Comparing persons who drank more than 2 cups per day with noncoffee drinkers, the odds ratio was .56 (95% confidence interval, .31-1.0). Comparing persons in the highest caffeine quintile with the lowest, the odds ratio was .31 (95% confidence interval, .16-.61). These relationships were consistent across subgroups at risk for liver injury and were relatively unchanged when analyses included the entire population or when limited to persons without impaired liver function or right upper quadrant pain. Fasting insulin concentrations did not mediate the effects. CONCLUSIONS: In this large, national, population-based study, among persons at high risk for liver injury, consumption of coffee and especially caffeine was associated with lower risk of elevated ALT activity.

Alanine Transaminase↗
PubMed2001

Urinary caffeine after coffee consumption and heat dehydration.

This study evaluated the effect of heat-induced dehydration on urinary caffeine excretion after the consumption of a strong coffee solution. Following ingestion of coffee (caffeine 4.9+/-0.1 [SE] mg/kg, 3-4 cups), ten healthy males were intermittently exposed to heat in a sauna until they had lost 2.9 % of lean mass. On a separate occasion, they consumed the same amount of coffee but remained quiet and euhydrated (control). Urine flow was reduced 7-fold in dehydration. At these low excretion rates (< 30 ml/h), caffeine concentration was negatively correlated with flow. Peak urinary caffeine (Cmax) was 7.6 +/- 0.4 (SE) microg/ml in dehydration and 7.1 +/- 0.2 microg/ml in the control (p > 0.05). Compared with the control, dehydration delayed Cmax by 1 hour, maintained higher saliva caffeine concentration (6.1 vs 5.2 microg/ml, p < 0.05) and a lower saliva paraxanthine/caffeine ratio (p < 0.001). The 24h-recovery of caffeine in urine was reduced (1.2 vs 2.8% of dose, p < 0.001), however at least 2.6% of dose were lost in sweat. These results suggest that the rise in circulating caffeine due to delayed metabolic clearance was partly opposed by a sizeable elimination in sweat. Therefore, heat dehydration did not lead to higher concentration of caffeine in urine after coffee ingestion.

Adult↗
PubMed1994

Potential sources of sugar for the phlebotomine sandfly Lutzomyia youngi (Diptera: Psychodidae) in a Colombian coffee plantation.

Sugar-deprived Lutzomyia youngi were exposed to each of the five most numerous plant species in a Colombian coffee plantation for 24 h and then tested for the presence of fructose by the cold anthrone assay. Many flies exposed to coffee (Coffea arabica) (up to 55% in an individual test) and guamo (Inga edulis) (up to 28.0%) gave positive results. Although some flies also took sugar from red-flowered balsam (Impatiens balsamina) and bamboo (Bambusa angustifolia), none of the insects exposed to plantain (Musa paradisiaca) gave a positive result unless the plants were infested with aphids (Pentalonia sp.). Although sandflies were successfully marked in the laboratory by exposing them to coffee and guamo plants whose roots had been treated with RbCl at 5000 p.p.m., RbCl was not detected by atomic emission spectrometry in wild specimens caught in the vicinity of RbCl-labelled coffee and guamo.

Animals↗
PubMed1998

Association of coffee, green tea, and caffeine intakes with serum concentrations of estradiol and sex hormone-binding globulin in premenopausal Japanese women.

Caffeine intake has been proposed to influence breast cancer risk. Its effect may be mediated by hormonal changes. The relationships between caffeine-containing beverages (coffee, green tea, black tea, oolong tea, and cola) and serum concentrations of estradiol and sex hormone-binding globulin were evaluated in 50 premenopausal Japanese women. Intakes of caffeine and caffeine-containing beverages were assessed by a semiquantitative food-frequency questionnaire. Blood samples were obtained from each woman on Days 11 and 22 of her menstrual cycle. High intakes of caffeinated coffee, green tea, and total caffeine were commonly correlated with increasing sex hormone-binding globulin on Days 11 and 22 of the cycle after controlling for potential confounders [Spearman correlation coefficients (r) ranged from 0.23 to 0.31]. Green tea but not caffeinated coffee intake was inversely correlated with estradiol on Day 11 of the cycle (r = -0.32, p = 0.04). Although the effect of caffeine cannot be distinguished from effects of coffee and green tea, consumption of caffeine-containing beverages appeared to favorably alter hormone levels associated with the risk of developing breast cancer.

Adult↗
PubMed1998

Meal frequency and coffee intake in colon cancer.

Several studies suggested that frequent eating may increase colon cancer risk. To further clarify this issue, a case-control study was carried out in six areas of Italy on 1,225 incident cases < 75 years of age with histologically confirmed colon cancer and 4,154 control subjects. The controls were hospitalized for acute, nonneoplastic conditions unrelated to long-term dietary modifications. After allowance for education, physical activity, intake of vegetables, and major energy sources, there was a trend of increasing risk with increasing eating frequency (odds ratio for > or = 4 vs. < or = 2 daily meals = 1.24). Coffee intake, which was inversely associated with cancer risk, exerted a modification effect, with an odds ratio of 1.89 for frequent eaters who drank fewer than two cups of coffee per day. Frequent eating increases, whereas high coffee intake decreases, the excretion of bile acids, which are suspected to be carcinogenic to the colon. Thus, it is conceivable that frequent coffee intake may counterbalance the effect of frequent eating.

Adult↗
PubMed1998

Tea and coffee consumption and risk of colon and rectal cancer in middle-aged Finnish men.

The association between coffee and black tea consumption and the subsequent risk of colon and rectal cancer was investigated within a Finnish clinical trial cohort. One hundred eleven cases of colon cancer and 83 cases of rectal cancer were diagnosed over a median of 9.0 years of follow-up. Proportional hazards regression models were used to derive adjusted relative risk (RR) and 95% confidence intervals (CI) for the association between coffee and tea consumption and cancer incidence. After controlling for confounders, coffee was not significantly associated with colon or rectal cancer. A positive association was seen for increased consumption of tea drinking and colon cancer. Compared with persons who did not drink tea, those who consumed <1 cup/day had an RR of 1.40 (95% CI = 0.84 - 2.33) and those who consumed > or = 1 cup/day had an RR of 2.09 (95% CI = 1.34-3.26, p for trend = 0.001). In contrast, tea consumption had little effect on rectal cancer incidence. This study does not support the hypothesis that coffee and tea protect against colorectal cancer risk. However, given the strength of the tea-colon cancer association and the significant gradient of risk we observed across level of intake, further epidemiologic research of this relationship in other populations seems warranted.

Aged↗
PubMed2006

Reliable indirect competitive ELISA used for a survey of ochratoxin A in green coffee from the North of Paraná State, Brazil.

The performance of an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a monoclonal antibody (mAb) for ochratoxin A (OTA) detection was evaluated in a comparative study with high-performance liquid chromatography (HPLC) analysis using 68 freshly harvested coffee samples from the North of Paraná State, Brazil. The anti-OTA mAb showed high specificity and low cross-reactivity with OTA analogues (OTB and OTalpha), but cross-reacted with OTC. This ic-ELISA showed a detection limit of 3.75 ngg-1 sample, when compared to 0.80 ngg-1 by HPLC, with an ic-ELISA/HPLC correlation coefficient of 0.90. As regards OTA analysis of these coffee samples, natural contamination was detected in 10 samples (14.7%) by both methods, where the ic-ELISA values (range 3.9-7.3 ngg-1) were 1.1 to 1.6-fold higher than HPLC data (2.7-4.7 ngg-1). Five samples (7.4%) were OTA positive (range 0.84-1.30 ngg-1) only by HPLC assay, probably due to the higher detection limit reached by ic-ELISA. OTA was undetectable in 53 samples (77.9%) by both methods, while all positive samples (range 0.84-7.30 ngg-1) showed OTA levels lower than 8 ngg-1 (maximum limit recommended by the European Union). The matrix interference of green coffee was minimized by dilution of sample extracts before carrying out the ELISA assay. This mAb-based ic-ELISA can be effectively applied for OTA screening in coffee, because it is simple, sensitive and sample preparation is easy.

Antibodies, Monoclonal↗
PubMedDate not supplied

Survey of imported green coffee beans for pesticide residues.

The US Food and Drug Administration carries out incidence/level monitoring in order to acquire data on the presence and amounts of pesticide residues in particular commodity/chemical combinations. In the survey reported here, imported green coffee beans were analysed for a variety of pesticide chemicals. A total of 60 green coffee samples were collected from 21 countries that are major exporters of coffee to the United States. The samples were analysed for organochlorine/organophosphorus, N-methyl carbamate, benomyl group and EBDC residues. Four samples had detectable residues: chlorpyrifos, 0.01, 0.02 and 0.04 ppm and pirimiphos-methyl, 0.01 ppm. The majority (93%) of the green coffee samples analysed in this survey had no detectable pesticide residues.

Coffee↗
PubMed1999

Caffeine in coffee: its removal. Why and how?

The popularity of coffee as a beverage is ever increasing despite the fact that there are reports antagonized to its consumption. Of the several factors cited, the alkaloid caffeine present in coffee can cause addiction and stimulate the central nervous system. It has an effect on the cardiovascular system with a slight increase in blood pressure and heart output. It undergoes biotransformation in the human body to form methylated derivatives of uric acid. In recent times, much effort has gone into the research on the removal of caffeine in coffee, resulting in a specialty product called decaffeinated coffee. Decaffeination methods mainly employ organic solvents or water or supercritical carbon dioxide. These methods with their attendant advantages and disadvantages are reviewed in this article.

Biotransformation↗