The application of nanotechnology to food science is gaining ground. Research is growing into how particles at the nano scale can be used for the development of new food products.  In this article, Food Engineering & Ingredients Magazine talks to Dr Arpagaus, from Büchi Labortechnik AG, about the latest developments in spray drying that are set to take the food industry by storm.
By Dr Cordin Arpagaus

Q1. Buchi has been developing spray drying technology for over 30 years. With your latest model the Nano Spray Dryer B-90, particle sizes in the nanometre range can be obtained. How does your technology make this possible?

Büchi Labortechnik AG has integrated a unique new technology into this spray dryer. It features a nozzle incorporating vibrating mesh components to produce extremely small droplets, which can be dried to very fine solid particles. An electrostatic particle separator is also present to collect the finest particles (down to the nanometre scale) providing very high recovery rates for even small amounts of powder. In addition, a patented heater technology gently dries delicate and valuable substances in a laminar gas flow.

Q2. What are the possible applications within the food industry for spray drying such small scale particles?
Typical spray drying applications include the production of milk powder, baby food, fruit juices or coffee extracts for easier dosage, lower volume and better conservation.
The Nano Spray Dryer B-90 focuses on small amounts of powder for very fine functional food additives, like vitamins, proteins, aromas, flavour enhancers, herbal extracts or other precious ingredients. Such heat-sensitive food additives are typically encapsulated in matrix materials like maltodextrin or gum arabic to maintain their vitality.

Other potential applications in the packaging industry are also foreseen. Here, food quality is improved by light resistant, oxygen protective or anti microbiological packaging materials based on novel nano scale features.

Q3. Are there currently any projects underway which uses the new
technology for food research?
Many researchers are very active in the development of nano food ingredients encapsulating nutraceuticals, a combination of food extracts (e.g. antioxidants) which have a medicinal effect (e.g. controlled release) on human health. Using Nano Spray Dryer B-90 technology it is possible to generate breakthrough innovations in this research field. For example, the very small spray dried particle sizes and the typically amorphous powder structure increase the bioavailability of food additives.

Q4. How important is it to fully research the way molecules act at the nano scale if materials are used to be in food?
It is crucial to be absolutely sure about product safety before releasing a new ‘nanofood’ ingredient onto the market. Nanoparticles have to be tested as if they were completely new substances, and there is a need to look at each individual case in detail. Feasibility studies have to be carried in order to measure toxicity and health impacts. So far, only a few nano ingredients are available on the market and we are still very much at the early stage of development. An example of this is research into fats or proteins and their novel properties for better handling, taste, stability or functionality. Research will continue to incorporate nanostructures into food processing systems for improved food quality and to promote human health.

Nanotechnology is an emerging area with massive potential and will attract interest from the public, some of whom will welcome it, while others will mistrust it. The particles produced in the Nano Spray Dryer B-90 are less harmful when compared to ordinary nano particles, because the particles produced by the dryer group together physically in micron-size agglomerates. These agglomerates will not cross the body’s natural defensive barriers.

Q5. Looking to the future, how do you envisage your technology will be used in the food industry over the coming years?
The food industry is increasingly turning to encapsulation technologies as a way of adding product value. Innovative spray drying techniques are becoming increasingly important to food manufacturers. While the focus has been on microencapsulation, more and more research is examining the potential for nanoencapsulation.
The new Nano Spray Dryer B-90 technology presented here is designed to enhance the health promoting properties of beverages and foods, whilst providing substantial protection against deterioration to the encapsulated ingredient during its shelf life.

Lab-scale spray dryers will be used in R&D laboratories and in academia in order to research formulations for new food ingredients. Small batches of highly valuable products in powder form will be produced. If an ingredient receives the green light for launch to consumers this  novel spray drying technology can then be scaled-up on an industrial basis.

The author
Dr. Cordin Arpagaus
Business Area Manager
Spray Drying
Büchi Labortechnik AG
Meierseggstrasse, 40
9230 Flawil 1, Switzerland