(1) Roses harvested for medicinal use are generally harvested in three phases and are divided into the following categories: "water flower", "water flower" and "water flower." Among them, the “headwater†has a thick meat, strong flavor, high oil content, and the best quality. The harvesting standard is a bud that has been fully expanded but not yet open. The time is from about the end of April to the end of May, before the flowering period. The flowers that are used to extract rose essential oils must be harvested during the open period of the flower. The time is about mid-May. This stage has the highest rose oil content. The harvesting standard is that the flowers are just open, showing a ring; if the flower heart is kept yellow, although the flowers are open enough, they can still be collected. If the red color is taken when the flower is red, the quality will drop significantly. The time for collecting flowers can be started from the early morning. The oil amount collected during the 8-10 hours is the highest; in case of low temperatures, the flowers can not be opened and the time for flower collection can be postponed. The edible flowers collect only the petals of the flowers in the flowering stage. (b) Processing and treatment of medicinal flowers requires gentle drying. The specific method of operation is generally to dry the water first, followed by the wood frame drying screen in the bottom of the wire mesh. Petals unified downwards or upwards, followed by the order to replace the slow fire baking, when the torus is crushed and was silky, indicating that it has been dried, generally 4 kg of water spray bake 1 kg, the other is 4.5 kg to bake 1 kg. When grading, it should be dry, red, bright and beautiful, evenly bloomed, and it should not be put down, rich in aroma, no mildew, no flaps or broken flaps. Flowers are open, sun exposure, scattered flaps, broken flaps are generally of poor quality. The dried flowers are generally packaged in paper bags and then stored in a tank with lime, covered and sealed. In the future, fresh lime is replaced every year during the rainy season. The processing method of edible flowers removes petals, receptacles and flower centers. 100 kg of petals plus 5.7 kg of salt, 3.5 kg of alum powder and 30 kg of melamine, rubbed evenly, and constantly turning, squeezed to juice, so that the weight is still about 100 kg, plus 100 kg of sugar, fully mixed and put on the altar spare. The salt in the formula is antiseptic; the alum makes the petal hard and non-sticky, adding to the appearance of beauty; plum brine (or citric acid) is to keep the petals bright, color does not retreat, after adding sugar into a small amount of sticky light brown liquid rose Red flower mud, with a strong nose and rose oil aroma, sweet and slightly salty. The extraction of rose oil is performed in the factory with specialized equipment and technology, and the oil yield is about 0.04%.
