From a scientific point of view, why is Kopi Luwak and Elephant shit Coffee just a hype?

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I'm afraid many people are no stranger to coffee, but do you know Kopi Luwak and shit-like coffee? What are their peculiarities? What's the difference in taste?

Kopi Luwak refers to the raw coffee beans that the civet eats the fresh coffee beans and digests the peel and flesh of the coffee berries through the intestines. Freshly picked coffee beans include exocarp, pulp (mesocarp), endocarp, silver coat (seed coat) and endosperm from outside to inside. Because the endocarp is so hard that civets can digest only the outer part, including exocarp and pulp, our daily coffee is processed only with the innermost endosperm. The processing of raw coffee beans includes peeling, degumming, dehydration, drying and shelling, where civets play a role in peeling and degumming. The silver skin will also be separated from the endosperm when heated during the roasting process and will not enter the final coffee solution.

Kopi Luwak not only takes advantage of the peeling and degumming of civets, which naturally like to eat coffee beans, but also choose coffee fruits whose skin is red and fully ripe (which is consistent with the need to pick fully ripe coffee fruits for high-quality coffee). In addition, the coffee fruit is in the civets' intestines and will experience the fermentation of civets' intestinal flora at appropriate temperature and humidity. Therefore, it can promote the balance of the overall aroma components of late-roasted coffee, which is precisely the view of the researchers of the National University of Singapore in their paper. In addition, the civet has an aromatic glandular sac in its body, which will increase the aroma of coffee to a certain extent. But at present, the Kopi Luwak on the market basically comes from captive civets, which are obtained by feeding coffee beans and then collecting and processing them.

How is the taste of Kopi Luwak different from that of ordinary coffee? The National University of Singapore once published a research paper on Kopi Luwak, which thought that Kopi Luwak tastes better than regular coffee. The authors found that Indonesian Sidikalang Kopi Luwak is more popular than the other three coffee because of its good balance of overall flavor, although its flavor is similar to that of ordinary Sidikalang coffee. Thailand's Doi Chang coffee and China's Yunnan coffee have a unique sulfur flavor, because the two coffee sulfur compounds reached 8.32 mg/kg and 12.63mg/kg respectively. Sulfur taste is particularly important for coffee quality. Half of good coffee is near the crater. Volcanic rocks are rich in sulfur, and sulfur compounds can produce a lot of coffee flavor substances.

In addition to Kopi Luwak, there is also like shit coffee (Elephant dung coffee). As a new thing, it is probably inspired by Kopi Luwak. According to the search results of scientific papers, there is not a single research report on the flavor of Elephant Coffee, only one about wild elephants in western India destroying local coffee plantations. The author even uses the word "Human-Elephant conflict" (human-elephant conflicts) to write this article from the perspective of harmony between elephants and humans.

As for the shit-like coffee spread on the Internet through the digestive system of the elephant, the enzymatic action breaks down the protein in the coffee beans, so the shit-like coffee does not taste bitter and has the aroma of milk chocolate, nuts, red berries and a little spices. this explanation is difficult to stand up to scientific argument. First, the endocarp of coffee berries is so hard that elephants are as indigestible as civets, so they have little effect on protein decomposition in the endosperm protected by endocarp. If elephants can digest the endocarp of coffee, people will not be able to pick out complete coffee beans from their feces. Secondly, protein does not belong to the substances in coffee beans that are harmful to flavor. On the contrary, protein is an important precursor of coffee flavor substances, which is degraded into peptides or amino acids in the process of roasting. Proteins react with other nitrogen-containing compounds such as peptides, amino acids, trigonelline and reducing sugars, acids and quinones to produce amino acid aldehydes and amino ketones by Mailard. The effect of elephant digestion of coffee fruit and pulp on the formation of coffee flavor substances related to protein is negligible compared with the reaction of protein in the process of high temperature roasting in the later stage. A large number of authoritative studies have shown that a large number of flavor substances are produced in the process of protein-related roasting. Although black gold-like gold has bitter taste, it also has antioxidant effect. It has the function of health care for human body.

There are many factors affecting coffee flavor, including coffee variety, origin, raw coffee bean processing, roasted coffee (degree), roasted coffee storage, grinding and so on. Arabica coffee from high-altitude areas has a higher flavor than Robesta coffee from low-altitude areas, which has been scientifically demonstrated by numerous laboratories. It can also be seen that the world's largest producer of Roberta coffee is Vietnam, where the trade price of raw beans is only about 2 yuan 3 of Arabica coffee, a high-altitude producing area elsewhere.

The most famous Kopi Luwak is produced in Indonesia, and the most famous shit coffee is produced in Thailand. Why don't Brazil and Colombia, as the main producers of Arabica coffee in the world, produce famous Kopi Luwak and shit coffee? The reason for this is worth probing into. Robosta coffee from low altitude areas has a fishy and musty taste, which all belong to bad flavor. In Southeast Asia, there is a way of roasting coffee with sugar (some with butter), which is called Torrefacto roasted coffee in western countries. This roasting method can strengthen the reaction of flavor substances and cover up the bad flavor to a certain extent. In some parts of our country, there is also a way to mix cheap Roberta and Arabica coffee to roast, and sugar is added to the roasting process. Arabica coffee is not suitable for growing at low altitudes, but coffee is an important cash crop in these areas. Yunnan coffee in China belongs to high-altitude coffee, which is of good quality and is very favored by large processing enterprises at home and abroad. it is mainly used to process instant coffee into supermarkets or traditional ground coffee to supply cafes in large and medium-sized cities.

Whether Kopi Luwak or shit coffee, it is OK to satisfy the psychology of curiosity. In fact, after this kind of coffee passes through the intestines and stomach of animals, the microbial index of raw coffee beans is easy to exceed the standard. Although the late roasting temperature reached about 200 ℃, enough to kill microorganisms, there are still some safety risks. The consumer price of Kopi Luwak or shit coffee can be directly compared with luxury goods is worth thinking about, among which there is no lack of manufacturers' hype and gimmicks.

Source: China Science Daily