Cultivars and Plucking
There are several jasmine cultivars planted in mainland China. In general, there are three main categories referring to the structure of flower petals.
1) Single-Petal Jasmine ( Dan-ban Mo-li)
In the early stage (before year 1963), this is the main cultivar planted for the production of jasmine tea.
The flowers blossom at an earlier hour (6-7 p.m.) as compared to the Double-petal jasmine (at 8-9 p.m.).This cultivar gives a fresh note of bouquet and with a refreshing taste to the jasmine tea.
However, the yield is much lower (1400-1750 kg/acre, 2800kg/acre at maximum), as compared to Double-petal jasmine (3500-5600 kg/acre, 10500kg/acre at maximum).
Besides, this cultivar is susceptible to plant disease and is not able to bear the cold weather and water logging condition during the rainy season.
These factors are unfavorable to the overall performance although it gives a good fragrance.
2) Double-Petal Jasmine (Dan-ban Mo-li)
Due to the above factor, other cultivar was developed and up to date, the Double-petal jasmine is the main cultivar being planted at most of the flower gardens.Other than producing a much higher yield of flowers, it can withstand harsher weather conditions and environment, and it is easy to plant. Besides, this cultivar gives a stronger and more intense fragrance.It is favorable for the production of jasmine.
3) Multi-Petal Jasmine (Dan-ban Mo-li)
After plucking, the flowers will blossom at 7-8 p.m.
Usually the 1st and 2nd outer layer of petal will blossom, and the rest of petal may blossom on the next day, or even sometimes never blossom but shrivel. The full blossoming of flowers will drag for many hours, and gives a milder fragrance. However, the yield is lower. Therefore, this cultivar is not suitable for the production of jasmine tea and less is being used. The flowering season of jasmine vary in accordance to different areas due to the variance of atmospheric temperature.
In general, there are four main seasons:
- 1)Spring-Named as (Chun-hua Xun), usually at around May, June, the yield is around 15% of total quantity in a year.
- 2)Summer-Named as (Xia-hua Xun), usually during July, the yield is around 30% of total quantity in a year.
- 3)Late summer-Named as (Fu-hua Xun), during August, the yield is around 30% of total quantity in a year.
- 4)Autumn-Named as (Qiu-hua Xun), during September to October, the yield is around 25% of total quantity in a year.
During spring, due to the lower temperature, and less accumulation of nutrition in plant, the yield is lower and of inferior quality.
During early spring and late autumn, the flower is rather small with a yellowish color and hardly blossoms after plucking; it is not suitable for the scenting process.
The best season for jasmine flower falls during summer until late summer. At this time, the temperature is higher, and there is sufficient sunlight and rainfall. These factors are favorable for the jasmine plant to produce more flowers with bigger buds and of superior quality.
The plucking of jasmine flower is meticulously carried out in order to collect the right flower. The standard is set based on whether the flower plucked is able to blossom at night.
The criteria must be as follows:
- 1) Select the 'right flower', which is named as (Dang-tian Hua).
- The characteristic of the right flower is: full petals in white color, with long stalk, i.e. the distance between corolla (Hua-guan) and calyx (Hua-e, the protective outer layer of leaves on a bud) must be far enough.
- 2) Do not pick the green bud (called Qing-lei).
- This is the flower without full petal and smaller size, not in white color but mix with greenish yellow color. The green bud is immature and will not blossom.
- 3) Do not pick the white flower (called Bai-hua).
- This is referring to the flower which has already blossomed and most of its fragrant oil has vaporized.
Plucking of the Tea Leaves
Ningde is known as the Kingdom of Tea Cultivars; here , it contains up to 11 cultivars of National Standard, with another 14 cultivars of Province Standard. In particular, Fu-yun No.6 and Fu-ding Big-white down (Fu-ding Da-bai-hao) is the main cultivars used. For these cultivars, the budding occur at earlier stage compared to others and have a higher budding rate.
The Fu-yun No.6 gives more fleshy leaves, while the Fu-ding cultivar has a more fleshy and robust bud that is covered with a lot of white down. With these factors, the pearl formed gives a more distinctive appearance in addition to its taste.
The plucking of fresh tea leaves starts during March. Usually, one bud with two or three leaves is hand-plucked.
After plucking, the leaves are transferred to a cool place indoors . The leaves are then spread to a thin layer. It must be carried out with much care and attention so as not to cause damage to leaf (damaged leaf will turn red and affect the quality of the end product). During this period, water vaporized from the fresh leaves is reduced to about 70%.
The spreading causes the leaves to omit greenish grassy smell, reduce the bitter and astringent taste, increase amino acid concentration which improves the briskness of liquor.
The process involves intensive manual process to obtain the jasmine pearl. The green tea is processed at early spring and kept until the jasmine flowering season comes, i.e. starting from June onwards.
The scenting process involves meticulous care to preserve the flower in order to obtain its divine fragrance into tea leaves.
Process of Green Tea Leaves used for Jasmine Tea?
Do you know why Premium Jasmine tea is in the pearl shape?
Tea leaf is made into the pearl shape which is the similar size and shape of jasmine flower so that when they conduct the mixing, tea leaf and jasmine flower could be very well mixed and the leaf could be effectively scented.
After plucking, the tea leaves will undergo 4 main processes:
(a)(Sha Qing) – Inactivation of Enzyme (Blanching)
This process is carried out using the drum or steamer heated at 260 dgree C. The purpose of is to inactivate oxidative enzyme such as polyphenol oxidase (PPO) with heat. With high temperature, it takes very short time to heat the tea leaves to above 80 degree C and inactivate oxidative enzyme. It will prevent the leaves turn to red color which is caused by enzymatic activity.
In the meantime, the high temperature is causing the vaporization of greenish grassy flavor of fresh leaves. Besides, leaves become softer after loosing water caused by heat. This is required to form the desired shape during the subsequent rolling step.
After the blanching, the soften leaf is rolled to form the strip-shape.
At this first drying step, the leaf is dried using machine to a moisture content of 30%, then spread and cooled down.
(c)(Rou Nian)-Rolling – Forming the pearl shape
After cooling, the leaf is proceeding for hand-rolling process. Intensive manual work is done to roll the leaf into the pearl shape. In a day, even an expert can only manage to roll as much as about 2kg of pearls.
The formed pearl will be dried using the machine.
Two steps of drying are carried out: the 1st drying at 110-120 degree C, followed by 2nd drying at lower temperature, i.e., 95-105 degree C. The semi-finished tea contains about 7% of moisture. The dried pearls will be kept until the florescence season of jasmine flower. During the storage, the water content of pearl must be controlled below 9%, and keep in air-tight condition and prevent from direct sunlight and humid environment.
Before the scenting process, the tea leaves must be re-conditioned:
Pearl will be carefully separated according to different sizes. Besides, it is sifted in order to remove broken pieces, tea dust or flakes
The semi-finished tea will be dried in machine heated to 100-110 degree C and reduced the moisture to 4-4.5%. The lower temperature is used to prevent the leaves become burnt and affecting the quality of made tea. The purpose of re-drying is to vaporize the excessive moisture trapped in leaves during the storage time. It helps to eliminate the unpleasant stale flavor from leaves.
After the drying, usually the temperature of pearl is at 60-80 degree C. The dried pearl will be spread out and cooled down to temperature which is 1-3 degree C higher than ambient temperature. If the pearl retains higher temperature, it will affect the scenting process. The blossom of jasmine flower is very sensitive to changes of temperature and lower temperature is favorable.
Preparation of Flower for Jasmine Tea
The freshly plucked flower must be well-taken care of following several steps:
Cooling of Flower
During the transportation of flowers to the factory, the temperature of flowers are gradually increased up to nearly 38C due to stacking and respiratory effect of flower. This is unfavorable to the physiological activity of flowers and will affect its blossom at the later stage. The flowers must be spread to a thin layer with a thickness of 10 cm for cooling down. If the flower is plucked after the rain, it has to be spread to an even thinner layer and blown with fan to accelerate vaporization of water.
Curing of Flower
The purpose of curing is to strictly control the temperature of piled flowers. This is the critical step to ensure the quality of the blossoms. Jasmine flower is sensitive to changes of temperature when it blossoms. The optimum temperature is 32-37C. If the temperature of piled flowers is lower than 30C, it is stacked to a thicker layer to keep-up the temperature up, whereas the flower is spread to a thinner layer when the temperature is above 38C.
During spring and autumn, the room temperature is lower. Usually the flowers are piled up to 30-40cm and even covered with cloth in order to keep-up the temperature.
Sieving of Flower
When 60% of the flowers bloom, sieving is carried out. The purpose of sieving is to separate the flower according to its different size. Besides, it also removes the green bud and stem. Only the flower with the right size will be collected and used. This is important to ensure the blooming occur simultaneously during scenting.
Mixing the Tea Leaves with Jasmine Flower
This is the critical step in the scenting process which affects the quality of finished product.
There are six crucial factors:
The ratio of pearl:
The quantity of flower used is related to the grading of end product. In general, the higher grade used more flower than lower grade.
In order to produce 100kg of special grade jasmine pearl, the total of 100 kg of flower will be used.
The 100kg of flower is divided for 4 times of scenting:
- First scenting-38 kg
- Second scenting-30 kg
- Third scenting-26 kg
- Final scenting-6 kg
For first grade, 3 times scenting is carried out without final scenting, and the number of scenting is reduced when for lower grade.
For 4th grade and above, the tea is first scent with waste flower (Hua-zha) collected from the final scenting of other high grade tea.
The whole process of mixing is carried out manually. At first, the total quantity of tea and flower is separately divided into 3-5 portions. The first portion of tea will be spread to a layer with thickness of 10-15cm, and then the first portion of flower will be scattered on top of tea. This is repeated layer by layer. When it is done, the worker will use the harrow to separate and blend the mixture, and leave it for 5-6 hours before the ventilation step.
The purpose of ventilation is
- 1) to reduce the temperature of mixture,
- 2) provide oxygen to flower for continual blooming,
- 3) release the carbon dioxide and others from mixture.
The worker will use the harrow to rake and spread the mixture to thickness of 10-15cm. It is repeated every 15 minutes and continues for 1 hour. When the temperature of mixture dropped to about 33-38 degree C, the mixture will be piled again to the thickness of 30cm and leave it for 5-6 hours again.
At times, second ventilation is necessary if the temperature of piled mixture rise to around 40 degree C again.
In total, the scenting process takes 10-12 hours. When the temperature of mixture increase over 40 over C again, the flower became shriveled and turned to yellowish color, and not producing the fragrance, it is time to remove the flower.
(Qi-hua)-Separate the flower
Once the scenting is accomplished, the exhausted flower must be removed immediately. If delay, the flower became stewed and giving the unpleasant smell to tea.
The timing of separating the flower must follow the rules:
- 1) When the temperature of piled mixture reached 41 degree C in first scenting, 40 degree C in second scenting, and 38 degree C in third scenting, respectively.
- 2) When the moisture content of piled mixture reached 17-18% in first scenting, 13-14% in second scenting, and 11-12% in third scenting, respectively.
After the first scenting, the tea is dried in order to reduce the moisture content. The temperature of drying is depends on the number of scenting:
- First scenting-110-120 degree C, the moisture is reduced to 5-5.5%
- Second scenting-100-110 degree C, the moisture is reduced to 5.5-6%
- Third scenting-90-100 degree C, the moisture is reduced to 6-6.5%
After drying, the temperature of tea must be reduced to below 40 degree C. Tea is then ready for subsequent scenting process (Zhuan-yin, means repeat scenting).
This is one of the secrets that give the very genuine fresh flowery note to the tea. The final scenting is carried out in order to increase the intensity of jasmine fragrance, and adding the natural and refreshing flowery note to tea.
Only the top grade of jasmine flower is used: with big petal, white color, and strong fragrance. For every 100 kg of tea, the flower used is 6-8 kg, depending on the moisture content of tea. In order to preserve most of its fragrance, the tea will not be dried after final scenting. Therefore, the moisture content of tea prior to final scenting is checked, and the quantity of flower used is calculated. The mixture is well-blended and piled for 6-8 hours. The moisture of final product is controlled below 8.5%. Exhausted flowers are removed once the scenting is accomplished, and jasmine tea will be packed into carton.