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Yes / A green approach has been used for co-crystallization of non-congruent co-crystal pair of caffeine – maleic acid using water. Ultrasound is known to affect crystallization hence the effect of high power ultrasound on the ternary phase diagram has been investigated in detail using a slurry co-crystallization approach. A systematic investigation was performed to understand how the accelerated conditions during ultrasound assisted co-crystallization will affect different regions of the ternary phase diagram. Application of ultrasound showed considerable effect on the ternary phase diagram; principally on caffeine/maleic acid 2:1 (disappeared) and 1:1 co-crystal (narrowed) regions. Also, the stability regions for pure caffeine and maleic acid in water were narrowed in the presence of ultrasound, expanding the solution region. The observed effect of ultrasound on the phase diagram was correlated with solubility of caffeine and maleic acid and stability of co-crystal forms in water.

Research on college student use of caffeine combined with alcohol (CAC) and public health concern over such use has been hampered by the absence of psychometrically sound measures of caffeine and CAC use. The present study examined agreement between survey (CAS) and interview (TLFB) methods for collecting data on caffeine, alcohol and CAC use. Participants were N=50 college students randomized to complete CAS followed by TLFB or the reverse. Qualitative follow-up interviews with N=15 participants were used to identify factors contributing to CAS-TLFB discrepancies. Responses varied by method of administration, with largest discrepancy magnitudes found for CAC, followed by caffeine, then alcohol use. Rates of reporting use by only one method were highest for CAC (65.5%). Lack of knowledge about caffeine was common, with over half (56%) having at least one caffeine misreport. Largest discrepancies were found for CAC use, an area of public health concern, particularly among college students.

While caffeine withdrawal has been well-characterized, research on caffeine intake and factors associated with withdrawal has been limited. The present study examined prevalence rates of caffeine use and identified psychosocial factors associated with having caffeine withdrawal headaches (CWH). Participants were N = 1,989 college freshmen who participated in the 2011 Spit for Science project. Caffeine use was reported by 80% of the sample. Females were more likely than males to consume caffeine, and soda was the primary source of caffeine for both genders. As hypothesized, daily caffeine users were more likely to report CWH than non-daily users. When multivariable analyses examined other variables identified through univariable analyses, the most parsimonious model for distinguishing between those with and without CWH included the following set of predictor variables: daily caffeine use; female; non-white minority; peers with alcohol problems; greater neuroticism, and those reporting maternal depression or anxiety.

While coffee culture has long since been positively associated with intellectual and working life, the health and safety of its primary stimulant, caffeine, has recently fallen under scrutiny by the FDA. This medical anthropology thesis provides a biocultural synthesis of caffeine culture, health effects, and biological variation in adverse effects related to pharmacodynamics and pharmacokinetics. Supporting evidence for variation in responses to caffeine was found through surveying 100 participants, investigating caffeine consumption levels, perceptions and health beliefs, adverse effects experienced, and medical encounters. Increased rates of adverse effects were found for students, pharmaceutical and over-the-counter drug users, and for participants reporting negative or ambivalent perceptions of caffeine, intolerance, or sensitivity to caffeine. Variation in rates of adverse effects suggests biocultural interactions account not only for patterns in pharmacological data, but are also clinically significant in constructing risk of caffeine intoxication. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Introdução: pesquisas sobre consumo de café têm sido feitas para determinar os componentes da bebida e suas respectivas funções, além de características sensoriais e efeitos associados à saúde humana. A cafeína é uma das substâncias psicoativas mais consumidas no mundo. Durante as últimas cinco décadas, seu consumo mundial per capita dobrou através do consumo de água cafeinada, de bebidas energéticas e, principalmente, do café. Por este motivo, muitos trabalhos têm sido realizados sobre os efeitos fisiológicos desta substância, resultando na impossibilidade de se chegar a um consenso sobre seus efeitos positivos e negativos. Tal dicotomia acarreta um aumento do consumo de café descafeinado, muitas vezes por aconselhamento médico. A descafeinação é realizada nos grãos crus inteiros, antes do processo de torrefação. A maioria dos métodos de descafeinação existentes utiliza solventes para extração da cafeína, como diclorometano, clorofórmio, álcool, acetona, água e outros, sendo o diclorometano mais utilizado no Brasil. Embora existam vários estudos sobre a composição química do café integral, pouco se sabe sobre a composição do café descafeinado. Tais modificações químicas podem acarretar não somente alterações nas características sensoriais da bebida, como também em termos fisiológicos. Objetivo: identificar o grau de aceitação e de preferência da bebida de café preparada com grãos submetidos a diferentes condições de extração da cafeína em consumidores habituais da bebida. Métodos: três amostras de café foram submetidas aos métodos: tradicional (não descafeinado), descafeinado pelo método químico (diclorometano) e descafeinado pelo método natural (água), depois torrados e moídos. Cento e dez consumidores receberam as amostras do café, de forma monádica e aleatória, e o açúcar ou adoçante porcionados. Os testes foram executados pelo teste afetivo de aceitação com escala hedônica (1: desgostei muito a 7: gostei muito) para 4 atributos (cor, aroma, corpo e sabor). O café foi preparado e filtrado na concentração 7%. Os resultados foram coletados e analisados prelo programa Fizz (Byosysteme) - ANOVA e Tukey, p = 0,05). As amostras foram submetidas à análise física para determinar umidade, cinzas, proteínas, lipídios totais, carboidratos e cafeína. Resultados: o café descafeinado tratado pelo método químico apresentou média abaixo dos outros dois cafés nos quatro atributos, mas com diferenças estatisticamente significativa para o sabor e corpo. Entretanto, em relação ao sabor, houve diferença estatística entre os cafés tradicionais e descafeinado com água e o descafeinado com o diclorometano. Foram encontradas diferenças significativas nas análises físico-químicas para proteína e lipídios nos cafés descafeinados em comparação ao tradicional Discussão: a extração de compostos do café pelos métodos físico e químico resultou em diferentes bebidas no que se refere ao sabor. O método químico pôde mudar as características sensoriais da bebida. / Introduction: researches have been made to determine the coffee components and its functions, sensory characteristics and effects related to human health. Caffeine is one of the most consumed psychoactive substances in the world. During the last five decades, the worldwide caffeine consumption almost doubled, mainly trough coffee. For this reason, many studies have been conducted on the effects of this substance, resulting in the inability to reach a consensus on its positive and negative effects. This dichotomy ultimately causes increased consumption of decaffeinated coffee, often for medical advice. The decaffeination and raw whole grains in place before the process of roasting. Several methods of decaffeination use solvents for extraction of caffeine, dichloromethane is the most used in Brazil. During the extraction of caffeine, the loss of other components is expected. Objective: identify the degree of acceptance and preference of coffee prepared with different conditions of extraction of caffeine for habitual consumers of the drink. Methods: three samples of coffee were obtained: traditional (not decaf), decaffeinated by chemical method (dichloromethane) and decaffeinated by the natural method (water) and after roasted and grounded. 110 consumers received the coffee samples, monadic and random, with portionated sugar or sweetener. Tests were performed with affective form of quantitative assessment of (1: I hate very much to 7: I like very much) for 4 attributes (color, aroma, body and flavor). The coffee was filtrated (concentration 7%). The results were collected and analyzed through the Fizz (ANOVA and Tukey, p = 0,05) The samples were submited by a physicochemical analysis to determine moisture, ash, protein, total lipids, carbohydrates and caffeine. Results: the decaffeinated coffee treated by chemical methods presented lower acceptance when compared with the other two coffees on 4 attributes, but with differences to the flavor and body. However, related to flavor, there was statistical difference between the traditional and decaffeinated coffees with water with decaffeinated with the dichloromethane. Significant differences were found in physical-chemical analysis for protein and lipids in decaffeinated coffee compared to the traditional one. Discussion: the extraction of different compounds of coffee by the method of decaffeination showed particular physical and chemical differences of coffee flavor on the extraction with chemical method. This chemical method might change the sensory characteristics of the drink. No differences were perceived through the physicochemical analysis.

Prior caffeine research has examined the effects of caffeine on performance using simple, lower-level cognitive tasks. The present study extended this work to investigate the effects of caffeine on performance and self-report mood measures during execution of a complex cognitive task. In a between-subjects design, 116 participants were administered either caffeinated or non-caffeinated chewing gum. Results showed higher fatigue and negative affect (NA) levels and lower positive affect (PA) and task performance levels in the placebo condition. These findings replicate prior findings on mood effects of caffeine; also, they extend the limited results on performance effects of caffeine by demonstrating moderate support for improved complex cognitive task performance after caffeine intake. Furthermore, these results show the efficacy of gum for caffeine administration in research.

A ninety minute competitive soccer match consists of many intermittent sprints resulting in fatigue, and consequently, a reduction in skill performance. The combination of caffeine and carbohydrate (CHO) has been shown to have ergogenic effects which help maintain skill measures during fatiguing states, however, there has been little research investigating this combination on soccer performance. Therefore, the aim of this study was to examine the effects of three sports drinks, including a placebo (PLA), a 6% CHO drink, and CHO + caffeine (CCAF; 5 mg/Kg body mass (BM)) on soccer-specific skills, throughout a fatigue-inducing soccer match. Twelve male soccer players completed three ninety minute intersquad matches played outdoors on a grass field in a randomized crossover design. Players consumed 5 ml/kg BM 45 minutes prior to kickoff and 3 ml/kg BM every 15 minutes during match play. Soccer passing skill was measured using the Loughborough Soccer Passing Test (LSPT), shot speed, and 20m sprint performance were measured pre-match, immediately at halftime and immediately post-match. Countermovement jump (CMJ) was measured pre-match and post-match. Heart rate (HR) was measured continuously. Blood lactate, rating of perceived exertion (RPE), and perceived fatigue were assessed every fifteen minutes throughout the match. Urine was collected pre-match for analysis of urine specific gravity (USG). BM was measured pre-match and post-match. LSPT total performance time was significantly better in the CCAF trial compared to the PLA trial at halftime (55.3 ± 10.3 s vs 66.5 ±8.7 s, p = .027). There were also significant improvements in penalty time (CCAF 8.2 ± 7.6 s vs. PLA 16.6 ± 7.8 s, p = .042) and movement time (CCAF 8.2 ± 7.6 s vs. PLA 16.6 ± 7.8 s, p = .028) during the CCAF trial in comparison to the PLA at halftime. HR and blood lactate was elevated throughout the PLA trial in comparison to the CHO trial. There were no other significant findings. Most players (50% - 83%) started all three matches in a dehydrated state (USG > 1.020). The CHO trial had significantly lower sweat rates (0.83 ± 0.25 L/hr) than both the PLA trial (1.06 ± 0.26 L/hr, p = .038) and the CCAF trial (1.11 ± 0.19 L/hr, p = .009). The addition of caffeine to a CHO sports drink significantly improved passing performance (quicker completion time and fewer penalties accumulated) over a PLA. All three sports drinks appeared to be equally as effective in preventing deterioration of soccer skill performance during a game situation. This suggests that the total volume of fluid consumed is of greater importance than the type of fluid. Caffeine appeared to have limited ergogenic effects on skill performance without any negative consequences. / Graduate