Apple cider vinegar: The darkest superfood in the American market

　　Apple cider vinegar in Europe and the United States and other countries is very popular, large scale, more kinds of products, and people have been used to apple cider vinegar as an acidic condiment to eat, with strict quality standards. Fruit vinegar was developed in Japan in the 1960s.

　　In recent years, the development of Fruit vinegar in Japan and Korea is very rapid and comprehensive. Among them, Japan has a wide variety of apple vinegar products, good quality, and strict production and quality standards. South Korea has also launched a variety of high-quality apple cider vinegar products, and has its own competitive products. Apple cider vinegar, marketed with cleansing/detox and digestive health as its main claimed features, generated $79,257,715 in sales through mainstream RETAIL channels in the US in 2020, up 133.8% from 2019.

　　Apple cider vinegar is a new beverage made from apple juice or concentrated apple juice through two fermentation: alcohol and acetic acid. Natural apple cider vinegar is made from fresh, crushed, organically grown apples and allowed to mature in wooden barrels. The standard for apple cider vinegar varies from country to country, ranging from 4% acetic acid (W/V) in the US to 5% in China. This new type of apple vinegar made by special fermentation technology, not only has the nutritional value of apple and health care function of vinegar, but also can reduce blood pressure, prevent arteriosclerosis, eliminate fatigue, and prevent alcohol, beauty, cold, fitness, weight loss, detoxification, and so on, loved by consumers.

Key techniques in apple cider vinegar

　　Making apple juice: The quality of apple cider vinegar depends on the ripeness of the apple, so it is best to select mainly ripe apples for brewing. Before brewing, apples are crushed and their soluble components are extracted. In extraction, pectinase should be added to decompose pectin in apple juice, promote solid deposition and improve juice yield. On the other hand, before enzymatic hydrolysis, it is necessary to add a certain concentration of SO2 solution to block and destroy the oxidase in apple juice, prevent the oxidation of apple juice, inhibit microbial growth and affect fermentation.

　　Alcoholic fermentation: activated yeast was inoculated into apple juice before fermentation, and aerobic respiration of yeast was mainly carried out in the early stage of fermentation to promote rapid reproduction of yeast. In the main fermentation stage, the yeast mainly breathes without oxygen. Through THE EMP pathway, the glucose and other sugars in the juice are converted to pyruvate, and further converted to acetaldehyde, and finally to alcohol. At the late fermentation stage, the activity of yeast decreased obviously, and the high alcohol content and low sugar inhibited the growth of yeast. At this time, yeast was prone to autolysis, so the fermentation temperature could be appropriately lowered to ensure the quality of fruit wine.

　　Acetic fermentation: Acetic fermentation refers to the process in which acetic acid bacteria oxidize ethanol to acetic acid. The early fermentation stage is the adaptation stage of acetic acid bacteria, the growth of bacteria is slow, the oxygen demand is small, so the ventilation should be reduced. In the middle stage of fermentation, the growth of acetic acid bacteria is vigorous, the number of bacteria increases greatly, and the oxygen demand is large. Therefore, the ventilation volume should be increased, and the acidity in the fermentation liquid should not rise any more as the fermentation end point.

　　Aging: Aging is crucial to the formation of flavor compounds in fruit vinegar. Fruit vinegar contains organic acids, amino acids, esters, aldehydes, phenols and other substances. In the process of physical and chemical maturation, through a series of complex biological and chemical reactions, such as oxidation, esterification, hydrolysis and acetal reaction, the unique flavor of fruit vinegar can be formed. After aging, fruit vinegar has strong aroma, clear color, thick texture and special flavor, and its quality is further improved.

　　Clarification and sterilization: in order to improve the stability and transparency of fruit vinegar, clarifying agent was added in the aged vinegar to clarify and filter the fruit vinegar, pasteurization technology was adopted to remove the metabolites of the bacteria in the fruit vinegar, so as to meet the health requirements of fruit vinegar.

The beauty of apple cider vinegar

　　Apple cider vinegar is a kind of acidic taste, single in the human body, alkaline beverage after metabolism, has the function of neutralizing acidic food, and is conducive to the preservation of various nutrients and calcium absorption. According to compendium of Materia Medica, vinegar has the functions of removing silt, detoxifying, digestion of qi, appetizing qi and dispersing water qi. In addition, apple cider vinegar also contains rich functional ingredients, such as malic acid, pectin, apple polyphenols and so on.

　　Malic acid in apple cider vinegar: Some organic acids in the apple cider vinegar is direct material of the Krebs cycle, such as acetic acid, malic acid, citric acid, it can produce energy directly into the Krebs cycle, faster than glucose metabolism, and therefore can make human body recover quickly, on the other hand, after a long time for work and after violent campaign, though in the body will produce large lactic acid, people will feel particularly tired, If the direct intake of apple cider vinegar at this time, lactic acid and other part of the organic acid can be through pyrogluconic acid to produce citric acid, in the process of energy generation to avoid further production of lactic acid, can promote the recovery of metabolic function, so as to eliminate fatigue.

　　Pectin in apple cider vinegar: pectin can delay the absorption of sugar and lipid in the intestine, and control the rise of blood sugar: pectin absorbs water and expands in the body, which can increase the volume to 10 times that of the original. It is easy to make people feel full, and delay the empelling of the stomach, and can effectively prevent obesity and weight loss. Pectin can absorb heavy metal ions such as lead, nickel and cobalt in food, and cannot be digested by digestive juices, so it effectively eliminates toxins from the body.

　　Apple polyphenols in apple vinegar: Apple polyphenols are the general name of polyphenols contained in apple. The main components include flavonols (quercetin ligand), hydroxyl cinnamic acids, catechins and their polymers, dihydrochalcone (rhizoptin ligand) and so on. Apple polyphenols can reduce cholesterol and fight atherosclerosis by promoting cholesterol metabolic decomposition and inhibiting intestinal absorption. Apple cider vinegar also contains a variety of vitamins, which have great antioxidant power. When paired with apple polyphenols, they form a full-on anti-aging system. Studies have found that aging is the result of the accumulation of oxidative products, such as skin brown pigment, age spots, wrinkles, are products of oxidative reactions. Therefore, apple cider vinegar has anti-aging and beauty benefits.