3D printing as novel tool for fruit-based functional food production

Highlights

• The 3D printing (3DP) of food is innovative approach in functional food production.

• The major benefits of 3DP are product diversity, customization and personalization.

• 3DP fruit products can be enriched with functional ingredients from various origins.

• Legislation that regulates safety of 3D printing in the food sector is still missing.

Daily consumption of fruits/vegetables has a preventive effect against several chronic diseases, mainly because of their bioactive compounds (BACs) and potent antioxidant activity. As consumers demand more of the health-promoting products, it would be a great challenge to enrich these products with functional ingredients that they do not naturally possess, such as lipophilic BACs, probiotics, proteins/peptides, and so on. Currently, a great potential in the field of food innovation can be achieved through 3D food printing (3DP). This is a technique for producing three-dimensional food products of any shape and dimension, with preferred flavors, and desired nutritional compositions. 3DP could be a promising tool to incorporate sensitive and easily degradable BACs and other functional ingredients into functional 3DP food products, making a great contribution to healthy food production. Therefore, 3DP could contribute greatly to increasing the consumption of fruits and vegetables and promoting health. Other advantages of 3DP include time and energy savings, sustainability, and personalized, reproducible food production. However, the safety of 3DP foods has been less extensively addressed. Nevertheless, the use of innovative non-thermal technologies can extend the shelf-life and nutritional value of 3DP foods. In conclusion, the application of 3DP in food manufacturing could overcome major limitations of traditional manufacturing and provide solutions to the challenges of processing fruit-based functional foods.

Introduction

When it comes to 3D printing technology (3DP) and its application in food sector, many promises, opportunities, and open doors have been mentioned for different prospects regarding nutritional aspects. The literature states that 3DP foods will enable personalized meals and digitized nutrition taking into account the individual’s age, physical/health condition (and fitness), nutritional status, and energy needs [1,2^••]. However, 3DP foods have not yet found industrial application, nor have they been integrated into supply chains [3].

On the other hand, modern society has identified obesity and chronic diseases as the major health problems. Therefore, in the era of digitized 3DP foods, the current strategy is to improve the recipes of common foods and increase their nutritional value. This can be achieved by reducing glycemic load and glycemic index (e.g. replacing calories from simple sugars with natural sweeteners such as Stevia rebaudiana Bertoni), while increasing soluble fiber (from oats and barley) and omega-3 fatty acids (e.g. Chia seed oil and flaxseed oil) [4]. Fruit-based 3DP foods are no exception, as the intake of sugars, micronutrients, fiber, and water-soluble vitamins is largely dependent on the fruits used [5].

Recent research shows that this technology has a perspective in 3DP of fresh vegetables using food hydrocolloids, instead of common freeze-dried foods, which may be suitable for dysphagic patients who have difficulty in swallowing food [6]. Although vegetables differ greatly in water and starch content, 3DP technology enables the production of optimized food inks based on vegetables modified with different hydrocolloids to obtain optimal rheological properties and texture. Moreover, the selection of suitable food for printing can be improved by using near-infrared spectroscopy (NIR). Chen et al. [7] showed that NIR spectroscopic parameters can well predict the rheological properties of purple sweet potato pastes and thus indirectly, but rapidly predict their 3D printability.

Despite these great (theoretical) possibilities of 3DP-technologies to design nutritionally controlled/adapted foods (when and if 3DP is used for common cooking) [8], there are few reports on the nutritional value of 3DP foods. To this end, Derossi et al. [9] designed an effective 3DP-fruit formulation that provides 5–10% of the daily energy, calcium, iron, and vitamin D needs of toddlers and preschoolers. Moreover, considering healthy and balanced diet strategies (strong enforcement of fruit and vegetable consumption as natural sources of BACs) [10], 3DP has great potential for creating of individual functional foods with health-promoting benefits. Some of the main advantages and disadvantages of 3D food print technology are given in Figure 1.