A good morning always starts with a beautiful brew that fills up the atmosphere of the room with a coffee aroma. Coffee is the seeds of a small tree originating from tropical Africa and native to few places in Asia. At the same time, wild coffee is found in the remote forests of Africa and on the island of Madagascar. Wild coffees are also found in other tropical countries like India, Sri Lanka, and Australia. It became famous worldwide as the slave trade spread to the Arabic empires, where it gained pre-eminence due to the Muslim ban on fermented alcoholic beverages.
A few species of this genus were then discovered, mainly Coffea arabica, Coffea canephora (variety Robusta), and Coffea liberica. They are being planted worldwide to establish plantations in places like Hawaii, Brazil, and Vietnam a long time ago. Coffee is then become the second most valuable traded commodity on the global stock market after oil. The market of the coffee is now worth fifteen billion USD, and it keeps growing.
Most of the coffee trees have tiered branches. The foliage is deep green with a smooth edge that is arranged in opposite pairs. It produces attractive white flower clusters that are located at the axials of the leaves. A coffee tree can be fertilized through cross-pollination by the wind. However, the quantity and quality of the yield can be further enhanced through cross-pollination by insects such as bees. To cultivate coffee trees, the preferred growing environment is humus-rich soil with light shade. Steady mild temperature is the optimal temperature for them that make them native to countries with tropical weather. Therefore, as would be expected of tropical plants, most are frost-tender. Additionally, they adapt well to being grown as house plants. Coffee trees can be propagated through the seeds or semi-ripe cuttings. The seeds used for germination into seedlings must be fresh to ensure rapid germination.
When we talk about coffee, the best known is Coffea arabica. It is found in the mountain rainforests of Ethiopia that are known as the source of coffee. It is commonly called arabica coffee or Arabian coffee, the coffee of commerce and still the most prized species. It is a lovely evergreen shrub for frost-free gardens or large containers in which one or two trees are unlikely to supply your coffee needs. Typically, it can grow to around fifteen feet high. The small size of white flowers with fragrance is found to be clustered along the branches behind the leaves. After fertilization, clusters of dark red fruits are formed. Each fruit consists of two seeds that are referred to as coffee beans. The coffee beans can be then extracted and dried, followed by roasting to become our familiar coffee beans. Arabica coffee contains higher sucrose contents than Robusta. Thus, Arabica coffee brews give an acidic taste after roasting. Therefore, it is considered a superior flavor compared to Robusta coffee.
Arabica and Robusta are the most famous varieties in the world. Arabica is more flavour as it takes only nine months from flower to ripe cherry planted at higher altitudes. On the other hand, Robusta takes a more extended period, which is ten to eleven months. The ripe arabica coffee fruits Arabica are flat that usually fall from the tree, but the ripe Robusta cherries are oval that often stay on the tree. Arabica yields about one thousand five hundred to two thousand kilograms of beans per hectare at the optimal temperature of around fifteen to twenty-four degree Celsius. At the same time, Robusta produces more coffee fruits, which are two thousand and three hundred to four thousand kilograms of beans per hectare at the optimal range from twenty-four to thirty degree Celsius. The largest coffee producer in the world is Brazil.
The grade and price of the coffee beans are evaluated based on their aroma, flavor, acidity and balance. Commonly, the shape and size of the bean play a pivotal role in determining the flavor of the coffee as the more giant beans tend to give more flavor compared to smaller beans. This is because the degree of the roast varies according to the size of the beans in the roasting process. Generally, coffee beans are roasted, ground, and brewed to become one of the most popular beverages in the world. At first, a coffee cherry is harvested and categorized into natural coffee and washed coffee. A dry-processed coffee is known as natural coffee, whereas a wet-processed is categorized as washed coffee. There is an intermediate process called a pulped natural process that results in pulped natural coffees. Ideally, the coffee beans are collected when they are fresh and ripen to leave the least possible damage to the tree.
Subsequently, the coffee cherries are stripped by removing all the cherries present on a branch regardless of their degree of ripeness. After that, mechanical coffee harvesting came into the place whereby two alternative technologies, light handheld harvesters and large mechanical machines on wheels. It is followed by postharvest processing, in which the cherries will eventually undergo either dry, pulped natural, or wet processing immediately after the harvesting. To ensure the top quality of the coffee beans, the processing technique is much more significant compared to selective coffee cherries picking through manual harvesting at maximum ripeness.
After harvesting the coffee beans, the whole beans are proceeded to dry. Some countries use the sun to dry the coffee naturally, specifically for nonselective harvesting. The dried coffees are a mixture of unripe, ripe, overripe, and partially dry cherries, thus producing a low quality of coffee beans. High-quality coffee beans should have separation and processing together to make sure the quality is controlled. The separation can be done by separating floating and sinking cherries before drying. Next, both exocarp and mesocarp are removed during wet processing before drying. After that, the pulp (outer skin) and mucilage are torn off from the coffee cherries. The remaining beans are undergoing natural fermentation that can be conducted as a dry process or underwater. The fermentation process is crucial as it determines the coffee quality because over-fermentation will result in surplus productions of metabolites like short-chain fatty acids and esters, which prejudice coffee quality at high concentrations.
The coffee is kept in a fermentation container until the mucilage is wholly digested and ready for washing. Natural fermentation can speed up with the help of enzymes or yeast, which is Saccharomyces or with hot water. The microorganisms involved in fermentation metabolize the sugar content found in the fruits, which excrete organic acids and other metabolite products as results that give the final sensory characteristics of the beverage. Lastly, the beans are washed and then allowed to dry in dryers that remove the moisture from about sixty percent to twelve percent before roasting and packing. The last step, which is the drying process is the key to ensure it can be last long throughout the storage period or otherwise fungal growth that will produce off-flavours and mycotoxins that are no longer safe to be consumed.
The coffee market mainly focuses on and comprises coffee in different forms like roasted, instant, and ready-to-drink (RTD). Coffee has different tastes and brands as well as prices because the flavor of a roasted coffee varies according to the geographical location of the origin, variety, climates, the process of processing, roasting, and preparation. However, the taste and quality depend on the sensory properties of the consumer preferences and the emotions and attitudes toward the coffee. The bitterness of the coffee brew is an art that various compounds can influence. Coffee is famous for the main caffeine, which is a methylxanthine that is heat stable. Caffeine plays a significant role in giving bitter sensory characteristics. As compared to roasted Robusta beans, Arabica has only half of the caffeine concentration of Robusta. Therefore, this made the coffee brews using Robusta beans gave a higher level of bitterness.
Roasting is a stage where coffee beans upgrade their price to a higher level, as caffeine is less likely to be affected by roasting. The contents of the coffee beans like chlorogenic acids under drastic changes that produce a different generation of a wide range of coffee flavor-determining compounds. The significance of the roast aroma is the key to judge a good coffee. Some coffee industries used green beans instead due to their free amino acids.
Based on the study, a hobby to drink a coffee can be motivated by the liking, traditional eating, and habits, need and hunger, health, convenience, pleasure, genuine concerns, sociability, price, visual appeal, weight control, affect regulation, social norms and image, choice as well as variety seeking. The motivations are varied depending on the culture, age, gender, location, and mealtime of the person. Furthermore, the sensory characteristics of coffee are differed based on the packaging as well as branding. Different brands of coffee have different methods in the varieties, agronomic and environmental conditions, primary, secondary, and tertiary processing, storage, packaging, brewing, and serving.
Coffee is a beverage that is the most widely consumed physiological stimulant on the globe. It has some side effects that may influence cardiovascular outcomes. This is because caffeine has been proved to be responsible for cardiovascular effects as it helps raise blood pressure. Therefore, it is advised that elders or people who suffer from cardiovascular diseases like high blood pressure avoid drinking coffee. However, no defined report has been made on standardization of an apparent reference for the minimal daily coffee consumption.
Nonetheless, with the increasing interest in analytical research, it has been found that coffee has several potential active compounds like antioxidants and polyphenols that have beneficial effects on human health. Due to the presence of caffeine, the pregnant lady shall avoid the intake of coffee and tea. Most of the potential beneficial effects of the coffee are exhibited by the main components of the coffee like diterpenes, trigonelline, and melanoidins, apart from phenolic compounds and caffeine.
In coffee beans, the phenolic compound is mainly chlorogenic acids and tannins, lignans, and anthocyanins, responsible for determining the quality, aroma, and flavor of the coffee. The chlorogenic acids, which are under a family of esters, have proved that antioxidants reduce oxidative stress. Moreover, caffeine may have an “addictive” effect, a dose-dependent manner with improved serum concentrations. It may help to counteract the hepatic fibrinogenesis pathway by downregulating the production of connective tissue growth factors. With the daily consumption of coffee, the body will start to “immune”, which is known as caffeine dependence. However, caffeine addiction is not a formally recognized condition that is related to a health issue.
When we stepped into a coffee shop, some of us may be confused if we have no idea how to differentiate the coffee based on the barista menu. Before ordering a cup of coffee in a café, we must know what an espresso is. It is a short and robust drink. About thirty millilitres served in an espresso cup. Double espresso or doppio is a double portion of espresso in a cappuccino or espresso cup. Some may call it two shots of espresso. A shot of espresso that is topped with whipped cream and served in an espresso cup is espresso con Panna. At the same time, espresso with a bit of milk foam that summed up about fifty milliliters and served in an espresso cup is termed an espresso macchiato. Moreover, a glass of double espresso, around one hundred and fifty to two hundred and forty milliliters with lightly frosted milk, is categorized as flat white. A frappé is a rich iced coffee made of espresso, milk, and ice with flavored syrup mixed in a blender and served in a three hundred milliliter latte glass.
Generally, americano, known as espresso americano, is the espresso added with one hundred to one hundred and fifty milliliter hot water served in a cappuccino cup. It has a sequence whereby the espresso is added followed by hot water, leading to over-extraction of the taste. A dessert lover would love to have affogato in which the vanilla ice cream is served in a cup; then the espresso is poured over the ice cream.
A cup of caffѐ latte is a tall and mild coffee that is about one hundred and fifty to three hundred coffee added ‘milk’. It is made with an espresso with steamed milk followed by a bit of milk foam poured over it served in a latte glass or a coffee cup. Flavored syrup or chocolate sometimes are added. Besides, an iced latte is a coffee drink made of ice, cold milk, and an espresso in a latte glass. It can be mixed with some sugar or flavored syrup. A caffѐ latte added with chocolate and whipped cream is referred to as caffѐ mocha. It is made by topping two cl of chocolate sauce into the glass, followed by an espresso shot and steamed milk. Iced mocha is similar to an iced latte, but it is garnished and flavored like caffe mocha. Then, a latte macchiato that is served in a latte glass is a traditional caffe latte with a thicker layer of foam.
A cappuccino is a classic coffee that most people will order as the barista will make different patterns on it with chocolate and syrup. It is a coffee drink consisting of espresso, and a milk foam mixture served in a cappuccino cup. The drinking size of cappuccino is about one hundred and sixty to two hundred and forty milliliters. Cappuccino offers many variations in terms of the patterns of the milk foam, and there is a competition for a barista to design the unique patterns. It is well-known that cappuccino is an ‘Instagrammable’ coffee. Apart from that, freakshake made of cold brew coffee, blended, mixed, or stirred with various toppings, is also very ‘instagrammable’.
Furthermore, one can have cold brew coffee that tastes smooth and prepared by brewing freshly ground coffee in cold water served as a cold beverage. Those who like to have an enhanced version may go for Irish coffee, a classic coffee cocktail. It is made of Irish whiskey with filter coffee and topped with a thin layer of gently whipped cream. Then, a French press is a French morning coffee that mixes dark roasted filter coffee and warm milk, which is served in a bowl or a large coffee cup. It is also known as café au lait. A lungo or espresso lungo is an espresso pulled long and served in an espresso or cappuccino cup with the serving volume at fifty to sixty milliliter.
Additionally, ristretto or espresso ristretto is a very short shot of espresso that is about twenty milliiter only for those who preferred fewer caffeine beverages. For those who are advised not to drink caffeinated drinks or sensitive to bitter taste, one may go for decaf coffee in which about ninety-seven percent of the caffeine are removed by washing in the solvents like water, organic solvents, or carbon dioxide. Decaf coffee should have nutritional value that is similar to regular coffee.
Now, Vietnam is the largest producer of Robusta coffee and the second-largest producer of coffee worldwide. Vietnamese-grown coffee is well-known as it used a medium to coarse ground dark roast coffee that put inside a small metal Vietnamese drip filter. After this, the hot water is added, then wait for it to release the drops of hot coffee that are slowly dripped into a cup. When the process is completed, the finished coffee is poured into a glass full of ice, thus making the finished Vietnamese iced coffee. It also can be added with sweetened condensed milk before the drip filter process. Many Asian countries used sweetened milk or evaporated milk into the coffee instead of milk.
Besides, there is a unique coffee produced mainly on the Indonesian islands of Sumatra, Java, Bali, Sulawesi, and East Timor. It is known as civet coffee, which is commonly known as kopi luwak in Bahasa. The Arabica coffee cherries that are partially digested, eaten and defecated by the animal are the Asian palm civet (Paradoxurus hermaphroditus). There is a fermentation process occurred when the cherries pass through the intestine of a civet. Traditionally, the feces from wild Asian palm civets are collected from the wild, thus, making it an intensive farming method. This method offers the beans at one thousand and three hundred per kilogram for the beans that are collected from the wild as the civets will choose and select to eat good quality cherries.
Due to commercialization, many wild civets are caught and kept in the cage to make them constantly produce the ‘products’ to be commercialized. Therefore, it has been called one of the most expensive coffees globally to cost about one hundred US dollars per kilogram for farmed beans. However, the taste of the civet coffee is giving a typical taste compared to regular coffee beans. This novelty coffee, civet coffee production, raised awareness of animal welfare, in which intensive catching the wild civets caused an imbalance in the natural ecosystem. Thankfully, research was conducted by synthesizing the enzymes claimed to have the enzymes involved in the digestion process in the guts of civet.
Caffeine (1,3,7-trimethylxanthine) is a purine alkaloid found in coffee beans, tea, yerba mate, cocoa, and other plants known as a stimulant drug that targets the central nervous system. Moreover, this stimulant compound is commonly added to many consumer products such as energy drinks and colas. With such “symptoms”, caffeine dependence can be defined as the mechanism of action that blocks adenosine receptors A1 and A2A. Adenosine is a by-product of cellular activity that gives the feelings of tiredness and the need to sleep. Therefore, caffeine stops and block the receptors that result in high levels of natural stimulants, dopamine, and norepinephrine. Caffeine will disturb the sleeping time if it is consumed within six hours of bedtime. This indirectly disturbs the body healing time that affects the total body health and immunity for the long term. The use of caffeine is categorized as dependence but not an addiction. This is because it is not addictive like a drug such as cocaine, morphine, and nicotine. However, a person who is caffeine dependent might suffer from several physiological effects that show some symptoms and negative ways in the range of mild to severe depends on the daily consumption.
The symptoms of caffeine dependence are mild, like headaches, nervousness, racing heart, insomnia and sleep issues, dizziness, cardiac issues, and hypertension. In pregnancy, it is not recommended to consume more than two hundred milligrams of caffeine per day, which strongly depends on the person’s health status. It is advised that children underage of eighteen not consume several caffeinated drinks within a day. One of the adverse effects is the increment of blood pressure and change in heart rhythm, which would indirectly lead to the increased risk of osteoporosis and hip fracture. Coffee is somehow associated with bones because intake of coffee leads to a slightly negative shift in calcium in the individual. Furthermore, with the consumption of coffee, while the amount of caffeine is remaining in the bloodstream, one will get “high”, energetic, and motivated. With the increase of blood pressure, the body temperature of the moment will slightly increase to warm the body.
With so many mild health concerns, if one suddenly quit the coffee, he or she may suffer some symptoms of caffeine withdrawal. The symptom is showed especially when caffeine begins to wear off, which was eliminated from the body through urination. Within one or two hours, the body will experience dehydration, and one might feel a crash in energy in which one is less likely to keep going without another cup of coffee. Depression or anxiety is often observed as one is no longer “high”, and therefore, one is advised to seek a consultant. Furthermore, caffeine addiction, which is always associated with other behavioral addictions like sugar addiction, is the actual cause of someone addicted to the intake of coffee at a large amount within a day. Instead of cutting the caffeine intake abruptly, an alternative like reducing the caffeine daily and weekly intake is a good practice and then slowly replace the beverages with decaffeinated version drinks.
On the other hand, it has been many potential health benefits through coffee consumption. Scientists had studied that coffee has excellent antioxidant content that helps in antiageing. It might reduce or prevent type two diabetes, provided the coffee served is sugar-free. Moreover, prevention of colorectal cancer, Parkinson’s disease, and lower risk of getting a hepatic injury, cirrhosis, and hepatocellular carcinoma are the advantages of having coffee at a moderate amount.
Besides that, coffee has an excellent adsorption property as a coffee adsorbent. Coffee residues are the by-products that are produced in considerable large quantities globally. It has been used in many downstream industries like facial cosmetic products and absorbents. Due to its excellent absorption property, it is often used as a smell adsorbent in perfume shops. By smelling different perfumes, our nose will not have nasal fatigue when the nasal receptors become less and less sensitive to specific notes, thus, making it difficult to tell one sample from the next. Therefore, coffee is used in-between fragrance testing that “cleanse” out the nasal receptors, which provide an untainted smelling palate.
Spent coffee ground is the residue obtained during the brewing process that contains many organic compounds such as fatty acids, amino acids, polyphenols, minerals, and polysaccharides. Hence, it is an excellent source of organic fertilizer for all plants. However, it might induce soil acidification from time to time. It can be an excellent fertilizer as it can be processed into compost that helps to add nitrogen to the compost pile. It can be part of the organic materials to the soil that improve the drainage, water retention, and enhancement of aeration in the soil. Earthworms get attracted, especially the used coffee grounds are added to the soil (vermicomposting). It will lower the pH of the soil slightly, which is excellent for acid-loving plants.
However, the used coffee grounds can be neutral when they are rinsed, thus, giving the pH to around 6.5 that leave no effect on the pH of the soil. Therefore, many gardeners prefer to use it as a mulch for the plants, which is also used to keep the pests like slugs and snails away from the plants. Moreover, it is also believed that coffee grounds can be used as cat repellent when applied on the soil to avoid your flowers and veggies became the litter box of the cats.
Nevertheless, coffee is now known as a “forgotten” plant as it is become increasingly difficult to grow and cultivate due to the rise in temperature because of global warming. According to the research, scientists had suggested that fifty percent of the high-quality coffee will be unproductive by 2050.
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