The Intricacies of Spray Drying Instant Coffee

Spray drying instant coffee is a meticulous process that involves the removal of water from coffee beans through a rapid drying method known as spray drying. This technique employs spray dryers, renowned for their high drying rates and precise control over product quality. The system allows for meticulous regulation of variables such as the flow of hot air, droplet speed, and temperature, ensuring consistency and excellence in the final product.

The resultant coffee powder boasts a fine texture appreciated by many consumers. Beyond texture, the aroma of coffee is a symphony of volatile compounds, while non-volatile compounds contribute to its characteristic flavors, including sourness, bitterness, and astringency.

In spray drying, liquid coffee concentrate is atomized into a fine mist and introduced into intensely hot, dry air. The droplets swiftly evaporate, leaving behind the desired powdered coffee form. This rapid process, facilitated by high heat, generates particles of diminutive size, culminating in the powdered coffee renowned for its convenience and versatility. Thus, spray drying instant coffee emerges as a testament to precision engineering and culinary science, offering a flavorful and convenient beverage option for coffee enthusiasts worldwide.
The Intricacies of Spray Drying Instant Coffee

What is instant coffee?

Instant coffee, derived from genuine coffee beans, is the desiccated rendition of coffee. Following the extraction of the soluble and volatile components of the beans, the subsequent step involves removing the water, resulting in either a concentrated soluble coffee or a powdered form.

In the commercial sphere, instant coffee solids are generated using two primary techniques: freeze-drying and spray drying. Both methods facilitate reconstitution. The spray-drying procedure entails the dispersion of coffee extract into heated air, inducing swift desiccation of the droplets and their transformation into fine powder or small fragments.

Conversely, freeze-drying entails the freezing of the coffee extract, which is then fragmented into small pieces. Subsequently, these fragments are subjected to low-temperature desiccation under vacuum conditions.

Instant coffee demonstrates a proclivity for absorbing moisture from the surrounding environment, leading to clumping when the moisture content reaches around 7-8% w/w.

A solitary teaspoon of instant coffee may harbor between 30 to 90mg of caffeine, while a cup of ground coffee can contain 70-140mg.

Instant coffee boasts extensive popularity in numerous regions globally, occasionally constituting over 50% of coffee consumption in specific countries. Moreover, instant coffee offers the advantages of swiftness, cost-effectiveness, and ease of preparation compared to regular coffee.
What is instant coffee?

Chlorogenic acids – coffee polyphenols

Coffee contains many polyphenols, especially CGAs, which have purported antioxidant abilities. Chlorogenic acid (CGA), also known as 5-O-caffeoylquinic acid, is a polyphenol commonly found in human dietary products, especially in coffee beans.

Chlorogenic acids are phenolic acids with vicinal hydroxyl groups on aromatic residues that are derived from esterification of cinnamic acids, including caffeic, ferulic and p-coumaric acids with quinic acid.

Chlorogenic acids are naturally occurring phenolic compounds found in all higher plants. They have substantial biological activities and may be responsible for the beneficial effects of coffee on glucose regulation and the development of type 2 diabetes.

Due to their various biological properties, such as antispasmodic, antioxidant, inhibition of the HIV-1 integrase and inhibition of the mutagenicity of carcinogenic compounds, they are very important plant secondary metabolites. There is also evidence to show that chlorogenic acids exhibit anti-inflammatory activities by modulating a number of important metabolic pathways.

Chlorogenic acid activates endogenous antioxidant systems to defense and scavenge against free radicals. It enhances Nrf2 translocation from cytosol to the nucleus; thereby activating antioxidant gene sets to cytoprotection against cellular toxicity.

Chlorogenic acid significantly improved the impairment of short-term or working memory induced by scopolamine and significantly reversed cognitive impairments and decreased escape latencies in mice.

Chlorogenic acids exists in raw coffee and is also widespread in many kinds of seeds and fruits such as sunflower seeds and blueberries. It has also been found in the seeds and leaves of many dicotyledonous plants. It is thermally unstable and is readily decomposed to quinic acid and caffeic acid. Lower content of chlorogenic acids has also been detected in potatoes, tomatoes, apples, pears and eggplants, but consumption of these sources accounted for nearly 5–10% of that from coffee beverage source.

Chlorogenic acid strongly influences the taste of coffee, such as astringent, sweet, and sour tastes, which change with the concentration.
Chlorogenic acids – coffee polyphenols

Antiradical activity of coffee

Free radicals at physiological concentrations have a series of useful biological functions such as acting as a cell signaling molecule; functioning against cellular responses; controlling cell viability, migration, and differentiation; protecting cells against pathological and infectious agents and inactivating them.

However, levels of ROS (reactive oxygen species) higher than physiological concentrations cause oxidative-antioxidant imbalance and oxidative stress. Free radicals have been linked to chronic inflammation, origin and pathology of cancer, as well as neurodegenerative diseases.

There is a difference between “antiradical” and “antioxidant” activity. The antiradical activity characterizes the ability of compounds to react with free radicals (in a single free radical reaction), but antioxidant activity represents the ability to inhibit the process of oxidation (which usually involves a set of different reactions).

Green coffee is sources of antiradical for the human body enable to protect body organs from the influence of free radicals. Research shows that solutions of green and roasted coffee have significant antiradical activity against hydroxyl free radicals.

The main polyphenol compound in green coffee is the chlorogenic acid. When roasted, the content of chlorogenic acids decreases but at the same time, the content of high molecular compounds, and melanoidins (also possessing antiradical activity in coffee) increases.

Antiradical activity of coffee

Hawaiian Kona Or Kona coffee

The name Kona coffee means that the coffee must be grown within a very limited geographic area in the state of Hawaii. Kona coffee has a reputation for being one of the most expensive and sought-after coffee in the world.

Kona coffee representing a mere fraction of the world’s coffee and it grow in an area about twenty miles long and two miles wide. This strip that runs along Mamalahoa Highway in Kona Mauka also known as the Kona coffee belt. Coffee has been produced commercially for more than 170 years in Kona, despite periods of adverse economic conditions.

Kona coffee enjoys an international reputation as one of the world’s finest coffees. The coffee has a reputation for its sweetness, its caramel bouquet at first sip, followed by a floral aftertaste. The unique aroma profile of Kona coffee springs from a variety of Arabica known as Kona Typica or Guatemala Typica.

About 93% of the export market for Kona coffee is in Japan for all coffee types–green, roasted beans of regular and decaffeinated coffees while the remaining portion of exports is to other parts of Asia, especially South Korea and Taiwan, and also to Europe.
Hawaiian Kona or Kona coffee

Italian coffee drink: Cappuccino

Cappuccino is the strong coffee covered ('cappuccino' is a small hat or hood) with a layer of hot frothy milk topped with a dash of chocolate powder, 'caffelatte' (milk coffee), usually half coffee and half milk in a large cup or glass.

In the classic Italian-American cuisine, a good cappuccino consists one-third frothed milk, one-third steamed milk, and one-third espresso in a heavy 6-ounce cup.

In Italy, the milk is not frothed as thoroughly as in the United States, and is presented as a heavier, soupy foam that picks up and combines with the espresso, rather than floating on top of it, as is often the case with the lighter, drier froth typical of American production.

Cappuccino originated in 18th-century Viennese coffeehouses, where it was known as kapuziner. The addition of cream and sugar gave the coffee a brown color that was reminiscent of the hooded robes worn by friars of the Capuchin order.
Italian coffee drink: Cappuccino

Turkish coffee

Coffee was first made into a drink in Turkey during the Ottoman Empire, where it was usually drunk with herbs for extra flavour.

Turkish coffee is a method of brewing that’s popular across North Africa, Arabia and the Middle East.

It is brewed the finely ground coffee in small, long handled, tin-lined brass pots. The coffee beans are always freshly roasted and then pounded or ground to a very fine powder. When the boiling coffee it is important not to boil for too long, as the resulting brew will be bitter.

As the coffee is sweetened during the preparation, guests are always asked whether they would like theirs sweet medium, or plain, hence the need for several coffee pots in each household.
Turkish coffee

Coffee industry in Arabian Peninsula

The coffee industry began on the Arabian Peninsula, where Arabs became the first to recognize the commercial value of the lowly bean.

There is written evidence for extensive cultivation of coffee in the Arabian Peninsula by twelfth century. They cultivated coffee and by the 15th century, were growing it in quality in the Yemeni district, from which is spread by the next century to Syria, Egypt, Persia and Turkey.

Coffee beans

Coffee had always occupied an important role in traditional Arabian hospitality. Its preparation and serving, almost a ritual, requires a set of utensils that include a large steel spoon with a long handle, a mihmas that is used for roasting coffee beans over an open fire.

As the coffee industry expanded throughout the Arab countries, coffee became highly popular drinks, perhaps in part because the Quran forbids Muslims from drinking alcoholic beverage.

The first coffeehouses KavehKanes in the world opens in Constantinople in 1475, By end of the seventeenth century Dutch farmers started to grow coffee plants beyond the Arabian Peninsula, first in India and then in the Indonesia.
Coffee industry in Arabian Peninsula

Category of commercial coffee beans

The coffee beans that are commercially available can be divided into three categories:
*Mild coffees which are arabicas that were very carefully prepared. Their taste is mild, slightly acidic and pleasantly scented. Mild Arabica coffees are cultivated at altitudes over 2,000 feet above sea level, usually between 4,000 and 6,000 feet. They are produced from fruit that is picked only when ripe and prepared with care.

*Brazilian coffees, which are also arabicas, but are very diverse and have organoleptic characteristics are less appreciated. Brazilian Arabicas consists principally of Santos, Parana and Rio named after the ports from which they are shipped.

*African coffees canephora, which have a neutral taste that is less aromatic than previous ones. The robustas are full-bodies and are more bitter and bracing than the previous ones. Coffea canephora is indigenous to tropical West Africa (Benin, Burkina Faso, Cote d’Ivoire, Gabon, Gambia, Ghana, Guineas, Guinea-Bissau, Liberia, Mauritania, Niger, Nigeria, Senegal, Sierra Leone, Togo), eastwards to Uganda and north to south Cameroon to Northern Angola.

Both milds and Brazils come from trees that belong to the botanical species Coffee arabica. It still grows wild in Ethiopia and was first cultivated in commercial quantities in Yemen at the southern tip of the Arabian Peninsula.
Category of commercial coffee beans 

Coffee may reduce risk mental decline

Most people known that a cup of coffee can increase mental alertness and concentration and counteract the effects of tiredness and fatique.

Regular coffee consumption may reduce the risk of mental decline, dementia and Alzheimer’s disease. An important European study from the National Institute for Public Health and the Environment, Netherlands, suggest that older men may benefit mentally from regular and moderate coffee consumption and that three cups of coffee a day could slow the loss of mental function in men.

The elderly have a higher level of adenosine a brain chemical that weakens gamma rhythms, which are involved in memory and learning processes.

The caffeine appears to reduce the risk of memory loss and Alzheimer’s by blocking the effects of adenosine.

Coffee is brimming with anti-oxidants. Best results are reached when drink coffee from freshly grounded beans.
Coffee may reduce risk mental decline

Irish coffee

Then story goes that Irish coffee was created in the 1942 in the Shannon airport in Ireland, where it was a restorative drink served to weary passenger.

It was Joe Sheridan, the restaurant chef to top off hot coffee with a shot of Irish whiskey, all the better to warm a group of transatlantic passengers grounded by bad weather.

Today Irish coffee is as popular as ever. Irish coffee is one of the all-time great winter drinks, especially after dinner or for bunch.

The classic Irish coffee glass is an 80 ounces stemmed glass in the shape of a tulip that makes it nearly impossible to ruin the drink.

The coffee should be hot, fresh and strong. The cream should be thickened but still pourable, so that it will sit nicely on top of the hot coffee, allowing the drink to layer, such that the components come together only in the drinker’s mouth.

The original Irish coffee was a concoction of a bit of whiskey, a generous splash of black coffee and whipped cream.
Irish coffee

Coffee and heart disease

Coffee is among the most commonly consumed beverages in the United States and is the main source of caffeine intake among adults.

Regular coffee consumption has been associated with a lower risk of Type 2 diabetes mellitus and other cardiovascular risk factors such as obesity and depression.

A Harvard University study published in Circulation in 2015 found that people who drank three to five cups of coffee daily were less likely to die prematurely from any cause.

The study also found that they were specifically less likely to die from heart disease and stroke compared to people who drank little or no coffee. And drinking more than five cups of coffee per day didn’t favourably affect risk of death.

An analysis published in 2013 in Circulation compiled the results of 36 studies on coffee that included more than one million patients. Researchers concluded that people who drank coffee in moderation were significantly less likely to develop cardiovascular disease than those who didn’t drink coffee.

A newly published study (2015) of South Korean coffee consumers found moderate drinkers are less likely to have signs of blocked arteries than people who drank no coffee — or those who drank five or more cups a day.

The study’s participants who consumed between 3 and 4 cups of coffee per day had the lowest risk of clogged arteries developing, Dr. Yoosoo Chang of Kangbuk Samsung Hospital in Seoul and colleagues found.
Coffee and heart disease

Early writings about coffee

The first known reference to coffee in Arabic writings came from an Islamic physician, Abu Bakr Muhammad ibn Zakariya El Razi  also known as ‘Rhazes’ (852-932), who wrote a now lost medical textbook circa 900 AD.

In his medical textbook, AL-Haiwi (The Continent), Rhazes describes the nature and effects of a plant named ‘bunn’ and a beverage named ‘buncham,’ and what he says about the beverage’s effects is at least consistent with a reference to coffee.

The oldest extant accounts of coffee roasting date to the writings of the famous Islamic physician Ibn Sina, traditionally referred to in English-language texts by his Latinized name ‘Avicenna’. Avicenna’s praises of coffee were published in Arabic circa 1000 AD and translated into Latin circa 1200 AD.

Ibn Sina wrote of a average that ‘fortified the members, cleanses the skin and dries up the humidities that under it, and gives an excellent smell to all the body’.

And along with the coffee bean itself came the institution of the coffeehouse, which had become an important meeting place and source of news in the Arab World, William Biddulph, an English traveler, had noted in 1609 that ‘their Coffee houses are more common than Ale-houses in England…. If there be any news it is talked of there’.

Leonhard Rauwolf a German physician botanist, also traveler and he was the first European to write a description of coffee, which he saw prepared by the Turks in Aleppo in 1573.
Early writings about coffee 

Coffee and cancer

Coffee is widely consumed worldwide, and is substantial evidence from both laboratory and animal studies suggest its ability to reduce the risk of cancer.

Cancer is one of the most feared diseases. The carcinogenic potential of coffee has been investigated in several long term animal bioassays.

Studies suggest those who enjoy a cup of coffee every day or nearly daily have a lower risk for liver cancer than those who rarely sip a cup.

Feeding high levels of coffee as part of the diet did not produce tumors in either rats or mice (Nehling & Debry 1996).

On the contrary, some studies reported that instant coffee resulted in a decreased incidence of spontaneous tumors (Stadler 1990). The presence of antioxidants in coffee can explain the anticancer property of the beverage, but there are other compounds which might be involved.

According to the scientists, caffeine and caffeic acid, major coffee constituents have been shown to suppress mammary tumor formation in animal models and to inhibit DNA methylation in human breast cancer cells, respectively.

Coffee may also reduce risk through decreasing inflammation and influencing estrogen metabolism.

Research by National Institute of Environmental Health Sciences, North Carolina reported that cafestol and kahweol, which are naturally occurring diterpenes in coffee, have proved to have anti-carcinogenic properties.
Coffee and cancer

Coffee aroma and flavor

Each variety of coffee has its own flavor and other characteristics. Generally, marketed coffee is a blend of different varieties of coffee beans.

The blends are controlled for flavor, aroma, color and strength or body of the beverage from the roasted bean.

It has been established, primarily from gas chromatography evidence, that there are nearly 1000 different more or less volatile compounds present in roasted coffee.

Most results from the thermal decomposition of carbohydrates and phenols, especially chlorogenic acids that are present at significant concentrations in green beans during roasting.

Some compounds are located in the carbohydrate matrix of the roasted bean whereas others are located in the coffee oil distributed within the bean.

Heterocyclic aroma chemicals, which are major constituents of a brewed coffee extract possessed considerable antioxidants activities.

The flavor and aroma of coffee are best when it is freshly roasted. Many of the aromatic components of roasted coffee, and particularly of coffee oil itself, are extremely susceptible to deterioration by the action of moisture and oxygen.

The staleness of coffee exposed to air is due to the oxidative changes that take place with certain coffee constituents.

The major factor affecting coffee quality is the length of storage, as volatile aroma compounds are lost, especially from ground coffee, with methanethiol and 2,3-pnentanedione being used as indicators of coffee freshness, because they are rapidly lost on storage, especially the 2,3-pentanedione.
Coffee aroma and flavor

Coffee and Alzheimer

Over the past few years there has been increasing interest in the health benefits of coffee, as coffee consumption has been linked with better cognitive functioning and a lower risk of Alzheimer’s disease.

There are several studies showing that people who drink two or four cups of coffee each day are less likely to develop Alzheimer’s dementia that are people who do not drink coffee.

Scientific studies have shown that caffeine and other substances in coffee have a number of different effects on the brain that would be expected to improve one’s chances of avoiding dementia.

In one findings, shows that caffeinated coffee induces an increase in blood levels of growth factors GCSF (granulocyte colony stimulating factor). Researchers note that moderate coffee drinking (4 to 5 cups per day) starting in middle age may provide protection for Alzheimer’s symptoms and disease.

Based on animal study data, caffeine may prevent Alzheimer’s disease by protecting against beta-amyloid toxicity through adenosine A1 receptor inhibition.

Coffee also reduces inflammation and improves the health of the endothelial lining of arteries. Some substances in coffee also have significant antioxidant effects.

Together these beneficial effects of coffee offer the brain protection from some of the primary pathological processes that cause Alzheimer’s and other neurodegenerative disease to progress.

In Canadian Study of Health and Aging, daily coffee drinking lowered Alzheimer’s risk by 31 percent during five years follow-up.

In addition to direct preventive effects against Alzheimer’s disease, caffeine consumption may also indirectly inhibit cognitive decline via prevention of type II diabetes, a disease associated with accelerated rates of cognitive decline.
Coffee and Alzheimer

Coffee and dementia

Dementia is a group of conditions that gradually destroy brain cells and lead to progressive decline in mental function which is usually progressive and eventually severe.

The epidemiological evidence suggests that coffee consumption reduces the risk of cognitive decline, dementia and AD.

The caffeine in coffee is implicated as the active component associated with risk reduction of cognitive decline and dementia among coffee drinkers.

When people with mild cognitive impairment (a condition of loss of memory and other mental functions less severe than outright dementia) drank three to five cups a day, they cut their risk of progressing to dementia.

Scientific studies have shown that caffeine and other substances in coffee have a number of different effects on the brain that would be expected to improve one’s chances of avoiding dementia.

Caffeine grows brain cells in the areas of the brain responsible for long-term memory. Caffeine increase short-term memory, concentration, and the ability to think clearly.

Coffee reduces inflammation and improves the health of the endothelial lining of arteries. Some substances in coffee also have significant antioxidant effects.

These all effects would also tend to help prevent metabolic syndrome, heart disease, diabetes and other conditions that increase the risk of dementia.

Some 1409 participants of the Cardiovascular Risks Factors, Aging and Dementia (CAIDE) were followed for an average of 21 years. By 1998, a total of 61 cases were identified as demented (48 with AD).

Coffee drinkers at midlife has a lower risk of dementia and AD later in life compared with those drinking no or only little coffee.

The lowest risk (65% decrease) was found in people who drank 3-5 cups per day.
Coffee and dementia

Espresso coffee

In Italy a cup of espresso is a small heavy china cup with a capacity just over 50 ml, half full with a dark brew topped by a thick layer of reddish-brown foam of tiny bubble, also known as the Italian term ‘crema’. 

Crema contains oils and is one of the sure signs of properly brewed shot of espresso. It is created by the high pressure dispersion of gasses in the coffee.

Espresso is actually a coffee brewed from beans roasted medium to dark brown, with the brewing accomplished by hot water forced through a bed of finely ground, densely compacted coffee at a pressure of over 9 atmospheres.

Espresso is famous for being small, strong and black. It is the essence of coffee and the basis for many drinks, such as cappuccino and latte macchiato.

The name espresso is an Italian in origin. It was first coined around 1900 and loosely translated, means a cup so coffee brewed expressly just for you.
Espresso coffee

Coffee consumption and Parkinson’s disease

Parkinson’s disease is a chronic, progressive, movement disorder generally accepted as the second most common neurodegenerative disorder after Alzheimer disease.

Caffeine seems to have a protective result against Parkinson’s disease. 8004 Japanese American men who age were 45 – 68 years were enrolled in Longitudinal Honolulu Heart Program study between 1965 and 1968 by amount of coffee intake and by total dietary caffeine intake.

The findings indicated that higher coffee and caffeine intake was associated with a significantly lower incidence of Parkinson’s disease. The data suggested that the mechanism was related to caffeine intake and not to other nutrients contained in coffee.

An inverse association of both coffee and caffeine consumption and Parkinson’s disease has been reported in many case control and cohort studies.

A 22 year prospective study of 6710 Finnish men and women, age 50-79 at the outset of the study reported that those consuming 10 or more cups of coffee per day had a relative risk of 0.26 of developing Parkinson’s disease relative to those who did not drink coffee (Eur J Clin Nutr 2007).

The interaction of caffeine with the adenosine receptors on regular basis seems to provide protection to the brain cells from neurodegenerative disease, promoting long term health of the central nervous system. This effect of coffee is most dramatic in the case of Parkinson’s disease.
Coffee consumption and Parkinson’s disease

Caffè macchiato

Italians are crazy about their coffee and were the first Europeans to adopt the Middle Eastern drink.

A caffè macchiato is identical to an espresso macchiato, but should not be confused with a latte macchiato. 

A latte macchiato is steamed milk ‘marked’ with espresso, as its Italian suggest, whereas a caffè macchiato is an espresso ‘marked’ with a spoonful of milk foam. Macchiato literally mean ‘spotted’ in Italian.

It is normal for caffè macchiato: dot the surface of an espresso, in the usually small cup, with just a tablespoon or two of the milk, aiming to leave a brown ring visible around the edges.
Caffè macchiato