Bolaike Completes Freeze-Drying Process Experiment for Perfume Lemon Peel: Spiral Coil Cold Trap Locks in Natural Aroma

Perfume lemon is valued in the modern tea beverage and food industries for its unique, fresh aroma. This aroma mainly comes from volatile compounds such as terpenes, aldehydes, and alcohols, among which D-limonene is the primary contributor. However, these aroma compounds are extremely sensitive to temperature and begin to volatilize at slightly elevated temperatures, making them difficult to retain through traditional drying or sun-drying processes.

Recently, Jiangsu Bolaike Refrigeration Technology Development Co., Ltd. (hereinafter referred to as "Bolaike") completed a freeze-drying process experiment for perfume lemon peel commissioned by a client, successfully verifying the significant advantages of freeze-drying technology in locking in the natural aroma of lemon.

Freeze-Drying Process: Low-Temperature Aroma Locking, Restoring Freshness

In the experiment, the perfume lemon peel was crushed and evenly spread onto trays, then placed into a Bolaike laboratory freeze dryer. The shelf temperature was set at -30°C, and pre-freezing was carried out for 3 hours to rapidly lock the aroma compounds inside the material. After a 22-hour freeze-drying process, the results were ideal: the lemon flakes were dry and crisp, bright green in color, and exuded a rich lemon aroma, fully retaining the fresh fragrance.

The liquid collected during the defrosting stage of the freeze-drying process was also preserved. These liquids contain water-soluble flavor compounds from the lemon and hold high application value, and can be collected separately for subsequent product development.

Equipment Advantages: Spiral Coil Cold Trap and Stainless Steel Shelves

The ideal aroma retention achieved in this experiment is closely related to two unique design features of the equipment.

In terms of shelves, the equipment uses stainless steel shelves with an internal spiral circuit design. Compared with conventional equipment, the shelf temperature is more uniform, the material is heated evenly, and the finished product has better appearance and higher quality.

In terms of cold trap structure, conventional freeze dryers mostly use straight-tube cold traps, where frost forms on the inner wall of the chamber, resulting in average water capture efficiency. The equipment used in this experiment, however, adopts a spiral coil cold trap, with refrigerant circulating inside the coil. The cold trap contacts the air more fully, achieving higher water capture efficiency and capacity. During freeze-drying, aroma compounds are drawn into the cold trap along with water vapor and frost forms on the coil. During defrosting, water and aroma compounds are retained together. At the same time, the chamber is made of stainless steel, avoiding rust contamination and making the collected defrost liquid cleaner.

Experimental Data Can Be Reused, Supporting Pilot and Mass Production

This laboratory freeze dryer can simulate the freeze-drying process of medium and large industrial equipment. The temperature curves and process data obtained can be directly referenced for pilot-scale scale-up or direct introduction into mass production lines, without the need to readjust parameters from scratch.

About Bolaike

Jiangsu Bolaike Refrigeration Technology Development Co., Ltd. was established in 2014 and is a national high-tech enterprise specializing in the R&D, manufacturing, and sales of vacuum freeze-drying equipment. The company's technical accumulation can be traced back to 2003, with long-term focus on the design and production of industrial-grade freeze-drying equipment. Its products are widely used in food, pharmaceutical, and biotechnology fields. The company has independent import and export rights, and its products are exported overseas. Bolaike and Xinshidai Freeze-Drying Technology Research Institute (Jiangsu) Co., Ltd. jointly hold multiple patents related to freeze-drying equipment, and have established close cooperative relationships with universities such as Jiangnan University and China Agricultural University.

If you have freeze-drying needs for perfume lemon or other fruits and vegetables that require complete aroma retention, please leave a comment below or send us samples. Bolaike can provide freeze-drying process testing services for you.