Taiwan camellias shake off their tragic image and welcome a gentle revival
Whenever the season of blooming, dazzling camellia flowers comes to an end, from the end of the year into the beginning of the next, farming families begin to get busy, harvesting one plump tea seed after another, then sun-drying, pressing, making oil and bottling it, producing the hard-won camellia seed oil.
The so-called "camellia seed oil" is in fact what most people commonly call "bitter tea oil." Many people back off the moment they see the word "bitter," so some processors have given it the beautiful name "camellia seed oil," hoping to get closer to consumers and help them rediscover this edible oil that has earned the title "Oriental olive oil."
In fact, whether called "camellia seed oil" or "bitter tea oil," both come from what botanical classification generally calls the "oil tea tree." Oil tea, together with olive, oil palm and coconut, is ranked among the world's four major woody oil plants. Planting oil tea not only helps with soil and water conservation and fixing carbon dioxide from the atmosphere; the oil pressed from it is rich in monounsaturated fatty acids, which benefit cardiovascular health. In addition, its high smoke point means it does not easily produce cooking fumes when heated, so it is regarded as a healthy oil, with many benefits.
↑Comparison of the appearance of small-fruit oil tea, large-fruit oil tea and ordinary tea tree seeds. (Photo / provided by the Taiwan Forestry Research Institute)
Therefore, civil society groups and processors such as Hualien's Dawang Vegetable Shop, the Lunshan tribe of Zhuoxi Township in Hualien, the Miaoli Sanyi Township Farmers' Association, and the Sanwan Jinchun Tea Oil Workshop have cooperated with tea farmers to restore the planting and management of Taiwan oil tea; and agricultural authorities, out of considerations such as safeguarding the safety and self-sufficiency of the nation's edible oil and improving the quality of domestically produced edible oil, including affiliated research units of the Council of Agriculture such as the Tea Research and Extension Station, the Taiwan Forestry Research Institute and the Tainan District Agricultural Research and Extension Station, have also launched related research on Taiwan oil tea.
A neglected Taiwanese treasure
Chen Chun-jen, assistant researcher at the Yunlin Branch of the Tainan District Agricultural Research and Extension Station, points out that bitter tea oil (also called "camellia seed oil") is the best health-promoting edible oil for women during postpartum confinement or for soothing the stomach, and is said to be the fine oil Empress Dowager Cixi used for skincare. In addition, the smoke point of bitter tea oil is above 220°C, higher than olive oil's 160°C, making it suitable for pan-frying, boiling, stir-frying, deep-frying and cold dressing alike.
In terms of nutritional composition, bitter tea oil contains richer monounsaturated fatty acids, tea polyphenols, vitamin E, chlorophyll and camellin than olive oil, helps gastrointestinal digestion, and is a natural antioxidant mild oil. Older people often say bitter tea oil has a stomach-warming effect and is most suitable for use in winter. Therefore bitter tea oil not only has the fine name "Oriental olive oil"; its benefits surpass those of olive oil.
According to data from the Agriculture and Food Agency, oil tea, originally native to South China, was introduced to Taiwan in 1910 as an afforestation tree species. Around the time of Taiwan's retrocession, it was widely planted in the northern, central-southern and eastern mountainous areas, and at its peak the planted area reached more than 3,000 hectares, with an annual output of 70,000 metric tons of oil tea seeds and about 2,500-2,800 metric tons of oil.
But this uniquely favored treasure later failed to match the economic benefits brought by fruit trees and other crops, so its area shrank sharply; on top of that, farmers managed it rather extensively, the trees grew weak, and they often bore fruit only every other year, with low yields. At present Taiwan's total oil tea area is about 1000 hectares, planted only sporadically in low-elevation mountainous areas. The top five townships by area are Alishan Township in Chiayi County (17%), Xinyi Township in Nantou County (13%), Sanxia Township in Taipei County (12%), Zhuoxi Township in Hualien County (8%) and Zhongpu Township in Chiayi County (7%).
Although Taiwan oil tea is planted only sporadically, bitter tea oil has always been in short supply on the market, and with the spread of health-conscious thinking, its price has risen accordingly. A 600-milliliter bottle of bitter tea oil or camellia seed oil ranges in price from eight hundred to more than two thousand yuan, so how consumers can choose truly pure, fresh, locally produced bitter tea oil is an important issue.
Bitter tea oil (camellia seed oil), tea seed oil and tea tree essential oil are very different things
Yin Hua-wen, a researcher at the Taiwan Forestry Research Institute, points out that people often see products on the market such as "bitter tea oil (camellia seed oil)," "tea seed oil" or "tea tree essential oil" and assume they are all extracted from the tea tree, but in fact their sources are very different. Bitter tea oil is obtained by pressing the seeds of the "cultivated oil tea," commonly called large-fruit oil tea, or of "Camellia brevistyla (also called 'fine-leaf camellia')," commonly called small-fruit oil tea; tea seed oil is pressed from the seeds of the ordinary "tea tree" used to make tea; tea tree essential oil is obtained by distilling the fresh branches and leaves of the "Australian tea tree."
According to botanical classification, cultivated oil tea (large-fruit oil tea), Camellia brevistyla (small-fruit oil tea) and the tea tree are all plants of the family Theaceae and the genus Camellia. Among them, large-fruit oil tea was introduced and planted from China, while small-fruit oil tea is native to Taiwan's low- and mid-elevation mountainous areas, and although the seeds of small-fruit oil tea are smaller, their oil content is higher than that of large-fruit oil tea. The Australian tea tree, however, belongs to the family Myrtaceae and the genus Melaleuca, and its appearance is worlds apart from oil tea or the tea tree, and the ways its oil is used are completely unrelated.
↑The appearance of the large-fruit oil tea tree. (Photo / provided by the Taiwan Forestry Research Institute)
↑The appearance of the small-fruit oil tea tree. (Photo / provided by the Taiwan Forestry Research Institute)
↑The appearance of an ordinary tea tree. (Photo / provided by the Taiwan Forestry Research Institute)
↑The appearance of the branches and leaves of the Australian tea tree. (Photo / provided by the Taiwan Forestry Research Institute)
Therefore the price of tea oil varies according to whether the raw material used comes from large-fruit oil tea, small-fruit oil tea or tea tree seeds, and according to differences in processing methods, resulting in differences in quality and price.
Cold pressing, hot pressing and the solvent method
The extraction methods for ordinary tea oil are mainly divided into three: cold pressing, hot pressing and the solvent method. In the "cold pressing method," tea seeds are processed and formed into cakes, pressed for oil at room temperature, and then left to settle to remove impurities. Cold pressing preserves most of the oil's nutrients and antioxidant components, making it suitable for both high-temperature cooking and cold dressing, but its drawback is a higher residual oil rate in the tea seed cake.
The "hot pressing method" first roasts or steams the tea seeds at about 80°C-135°C before pressing them for oil. Tea oil processed by hot pressing is darker in color and richer in aroma, but also carries a bitter taste, which is why people customarily call it "bitter tea oil." Because tea oil obtained by hot pressing has undergone high-temperature treatment, its nutrients are more or less damaged, but the advantage is a higher oil yield, so most of the "freshly pressed" bitter tea oil seen in tourist areas belongs to the "hot pressing method."
Another method, the "solvent method," soaks tea seed cakes in a solvent to dissolve out the oil, then separates the tea oil from the solvent. Taiwan Forestry Research Institute researcher Yin Hua-wen stresses that because people are used to using tea oil for cold dressing, tea oil processed and separated by the solvent method may retain solvent residue and is not suitable for direct dressing.
Because the cold pressing method is more labor- and time-intensive and has a lower oil yield, cold-pressed tea oil sells for more than tea oil extracted by hot pressing or the solvent method. To shake off the stereotype that "bitter tea oil" has a bitter taste, some operators call cold-pressed tea oil "camellia seed oil," to distinguish bitter tea oil from tea seed oil.
The truth that ninety percent of bitter oil tea raw material comes from China
Because the production cost of Taiwan oil tea seeds is relatively high, a very large proportion of the bitter tea oil sold on the market is pressed from tea seeds imported from mainland China. Some operators estimate that ninety percent comes from the other side of the strait.
Qiu Chui-feng, section chief of the Tea Division at the Tea Research and Extension Station, points out that tea oil is an industry the government of mainland China focuses on developing, so its cultivated area of large-fruit oil tea and its output of oil tea seeds rank first in the world, and it is also the largest exporting country. According to statistics from the General Administration of Customs under the Ministry of Finance, in year 98 the quantity of mainland oil tea seeds imported domestically was 5329 metric tons, with an import unit price of only 13 yuan per kilogram. And a 2010 survey estimate by the Taiwan Forestry Research Institute found that the daily wage of a worker harvesting oil tea seeds domestically is about 1,000 yuan, and each person can harvest about 70-100 kilograms of fresh fruit per day, so the average selling price of domestically produced oil tea seeds is about 200 yuan per kilogram.
Therefore, many oil pressing plants, based on cost considerations, mostly use imported mainland oil tea seeds, causing Taiwan's oil tea industry to face the problem of mixed seeds and mixed oil. Taiwan Forestry Research Institute researcher Yin Hua-wen points out that domestically produced large-fruit tea oil sells for about 800-1,200 yuan per 600 C.C., and small-fruit tea oil for about 1,500-2,200 yuan. When the market price is good, tea oil may be adulterated, especially if bitter tea seeds imported from mainland China are poorly stored during long-distance transport and become moldy, in which case aflatoxin may very likely be produced after pressing.
Huang Jie-ying, deputy general manager of the Jinchun Oil Making Workshop, says that bitter tea oil's share of Taiwan's edible oil market is less than ten percent, and nearly ninety percent of the raw material is imported from abroad, with China being the largest source. Because Taiwan's planting costs are too high, Jinchun long ago went directly to China to carry out origin management and inspection of oil tea, importing fresh oil tea seeds with no pesticide residue. By contrast, some operators import already-processed oil tea seeds without controlling quality at the production source, so quality is uneven and worrying.
Whether bitter tea oil is pure: no proof in a beheading boast, but fingerprints reveal the truth
In view of the possibility that tea oil sold on the market may be blended with other oils, some mobile vendors in tourist areas even sell "freshly pressed," "pure" bitter tea oil under the slogan "bitter tea oil, behead me if it's not pure." Since words alone prove nothing, the Taiwan Forestry Research Institute developed a rapid identification method using fingerprint spectra to verify tea oil's true identity. It found that some bitter tea oil sold in tourist areas was blended with soybean salad oil, something worth noting when buying.
Taiwan Forestry Research Institute researcher Yin Hua-wen says that although the type of vegetable oil can be judged by the senses based on color and aroma, "whether it is pure" often lacks objective evaluation indicators. Therefore the Taiwan Forestry Research Institute developed a "portable gas chromatograph" that can quickly identify the quality of edible oil, with sensitivity more than a million times that of an ordinary desktop gas chromatograph; by comparing similarities and differences in fingerprint spectra, or comparing the retention times of the volatile components of each oil with chemical standards, one can identify whether each oil is pure, adulterated or already degraded.
Using this "portable gas chromatograph," Yin Hua-wen collected 55 kinds of edible oil products, domestic or imported, including various brands of bitter tea oil, soybean salad oil and olive oil sold on the market, analyzed the spectral fingerprints of the different oils and compared them. The results showed that cold-pressed bitter tea oil from well-known brands produced in Taiwan's main oil tea production areas such as Miaoli, Nantou and Chiayi had consistent spectral fingerprints, indicating no blending, whereas bulk bitter tea oil purchased from vendors at certain tourist spots showed the spectral fingerprint response of soybean salad oil, confirming that unscrupulous traders did indeed use cheap edible oil to pass off as high-priced bitter tea oil.
Spectral fingerprints prove bitter tea oil's composition rivals olive oil
In addition, olive oil is famous for being rich in unsaturated fatty acids, with an oleic acid content of 56-84%, which can prevent and reduce cardiovascular disease and benefit health. Yin Hua-wen analyzed olive oil imported in original packaging from Italy and Spain and domestically produced bitter tea oil, overlaying and comparing the spectral fingerprints of the two edible oils, and found that the components in the spectra of bitter tea oil and olive oil were the same, both with high levels of oleic acid, verifying that bitter tea oil's name as the Oriental olive oil is not unearned.
However, Yin Hua-wen also compared the packaging of domestic and foreign edible oil products, and found that foreign products all use colored glass bottles to store edible oil, whereas domestic ones use transparent glass bottles, and even plastic bottles. Yin Hua-wen suggests that in order to keep edible oil from degrading, tea oil should also be packaged in dark glass bottles and, after opening, kept refrigerated as much as possible, so as to maintain quality without degradation.
The revival movement of Taiwan oil tea
Huang Jie-ying, deputy general manager of the Jinchun Oil Making Workshop, says that in the past, tea oil was not widely used domestically and consumers were a rather specific group, but as people increasingly value health, demand for tea oil has risen, and the price of imported oil tea seeds has also climbed, and may in the not-too-distant future catch up with the price of Taiwan's local tea seeds. With the future of tea oil looking promising and the price of imported oil tea seeds rising steadily, the revival of Taiwan oil tea can be expected soon.
↑Yin Hua-wen compared the packaging methods of domestic and foreign edible oils and found that imported oils in original packaging all use dark glass bottles, while domestic ones customarily use transparent glass bottles, and even plastic bottles. The material and color of the packaging bottle both affect oil preservation. (Photo / provided by Yin Hua-wen)
Recommended reading
CommonHealth Magazine–bitter tea oil, Taiwan's genuine good oil
Proceedings of the 2011 Symposium on the Review and Prospects of Taiwan Oil Tea Research
Cultivation and Utilization of Oil Tea
Dawang Vegetable Shop—camellia seed oil
Lunshan Tribe: locally sourced camellia seed oil
Sanyi Township Farmers' Association–Oil Paradise D I Y guided tour commentary