Applications of Spray Drying in the Food Industry

1. Spray Drying in Fruit and Vegetable Powder Production

China is a major agricultural country, and the fruit and vegetable industry has become a key sector, second only to grain. Fruit and vegetable powders have unique advantages; they not only overcome issues like poor shelf life and spoilage but also meet the growing demand for diverse, high-quality, and fresh produce. This creates a vast potential for development.

There are various methods for preparing fruit and vegetable powders, such as spray drying, hot air drying, vacuum freeze drying, microwave drying, temperature-variable pressure puffing, and ultra-fine grinding. However, due to its distinct benefits, spray drying holds a crucial position in the processing of these powders.

2. Application of Spray Drying Technology in Instant Tea Beverages

Instant tea beverages are solid tea products that dissolve quickly in water. They are increasingly popular due to their convenience, quick dissolution, low residue, minimal pesticide residues, and ease of adjusting concentration or blending with other foods.

Using Ganoderma lucidum and black tea as raw materials, a study investigated the production process of a solid beverage. The optimal formulation included 15% black tea extract, 35% Ganoderma extract, 1% citric acid, 8% granulated sugar, and 15% maltodextrin. The best spray drying conditions were an inlet temperature of 180°C, outlet temperature of 80°C, and a feed rate of 25 ml/min.

3. Spray Drying in Food Additives

Certain food additives can be negatively affected by environmental factors like light, oxygen, temperature, and moisture, as well as by their own unpleasant odors. This can hinder their application and impede the food industry’s development.

With the advent of microencapsulation technology in the 20th century, many of these issues have been resolved, and spray drying is key to this technology. Research has shown that varying maltodextrin concentrations and spray drying inlet temperatures can affect the betalain content in dragon fruit. The optimal conditions found were an inlet temperature of 155°C and a maltodextrin concentration of 20%.

4. Spray Drying in Health Foods

The polyunsaturated fatty acids (DHA and EPA) in fish oil are highly prone to oxidation, which limits their use and market demand in health foods. Microencapsulation of fish oil not only effectively prevents oxidation but also masks the fishy taste.

5. Spray Drying Technology in Other Food Areas

As research into spray drying technology advances and consumer demands for flavor and nutritional value increase, more products produced through spray drying are appearing on the market, such as egg yolk powder, whole grain powder, and seasoning powders.

Economic development and improved living standards have led to decreased consumption of whole grains in many areas. Since these grains are rich in dietary fiber and minerals—essential for the body—whole grain powders are increasingly favored by consumers.

Researcher Li Junan used spray drying technology to process various grains and fruits, including yam, black rice, corn, buckwheat, and oranges, and evaluated the impact of spray drying on the active functional components. Additionally, four types of functional beverages were developed using various spray-dried powders as base materials. Spray drying is also commonly used in the processing of infant nutrition products, with infant formula being the most prevalent example.