3D Printing Foods for Digestibility

Additive manufacturing is the process used by 3D printers to create objects. It means by removing excess raw materials; they only take the necessary matter in the form of powder or filament or liquid which the machine then solidifies or melts to make the object’s final shape rather than defining an object’s shape (2)

Different disease complications like dehydration and malnutrition can be life-threatening if there is no appropriate and timely intervention. A patient is not capable of swallowing food in a proper manner which is connected with devastating conditions like dysphagia. Modified food is needed in order for dysphagia patients not to choke on excessively structured foods.

Modification of food evenness using 3D structures printed with a 3d printer is a common method broadly used by healthcare providers So that the patients can distinguish the food which increases the intake of food in the patients. Another thing 3D printing can give to the health care providers is the customization of a particular nutritional substance by cautiously making the food ink formulations (Tan et al., 2018).

The printer must be programmed to work with foods such as starches, proteins and/or sugars in place of ink in the process of printing food. Printing food is carried out through very careful processes like layering tiny semi-solid particles on each other for the creation of proper edibles.

Food Encapsulation for Adsorption and Digestibility

The entrapment of non-compatible and active ingredients like enzymes, flavour, lipid, and vitamins within a carrier material’s matrix is known as encapsulation. Powders along with components creating amorphous structures are used a lot for encapsulation.

Foods are viewed as the delivery system of micro and macro-nutrients to improve the process of nutrition. The delivery system is widely used to encapsulate, deliver and protect bioactive components. On the other hand, the food industry is known to develop parallel systems to encapsulate, deliver and protect food components via food matrices design. Yet, the efficacy of the encapsulation process is determined by bioavailability preservation of these components, and the proper release of the content’s portion inside the GIT (Parada & Aguilera, 2007).

In recent times, several techniques have been originated to manufacture food ingredients that are encapsulated. Whereas, encapsulation technique selection relies on the final use of the product, as well as the core materials release property. Here, it is crucial to note that none of the available practices are considered to be applicable universally as food components are known to exhibit acute differences by means of molecular polarity, weight, stability, solubility, etc. This leads to the notion that varied encapsulation advances are being applied to meet the definite molecular and physicochemical requirements for a food ingredient. Food ingredients’ successful microencapsulation also hinges on the package load efficiency, core protection from the detrimental environmental situations, and release of the components to a specific gastrointestinal tract site.

The structuring of a matrix for the delivery for nutrients is a well-debated topic. It is imperative to comprehend and predict food disintegration kinetics, digestion process, and subsequent metabolism to form structured foods. Here it is crucial to note that devising a strategy to control the release of food nutrients at the target GIT is important as well. Here, biochemical, physicochemical, and physiological parameters influencing these methods should be understood as well.

Reis et al., (2010) studied that food encapsulation for digestion process creates lipid structures that are hard to digest. Maljaars et al., (2008) noted that the latter is also reducing the dimensions of lipid droplets; the reduction process promotes the digestion of the contents at the ileum which induces satiety. Boulby et al. (1997) recommended that the intake of fats can be compacted with the creation of a merged emulsion that results as creaming in the stomach to form a lipid layer. These functions would then be sending a signal to the brain on the satiety state. The rate of digestion for solid fat crystals in far less than that of liquid oil, this implies that the intake of lipid can be reduced further with the development of Pickering emulsions having a solid-state crystal at shells and the core being encompassed with liquid oil (Norton et al., 2007).

Another illustration of encapsulation is the assemblage of crystals which entrap non-compatible components (molecules) with the core. The method is used when an active component’s encapsulation via sugary co-crystallisation occurs.

Advanced Techniques to Analyse the Food Materials in Digestibility Study

Food study and designs have advanced with the advancement of novel means to analyze and visualize structures of food. Electron microscopy has empowered researchers to gain a better understanding of the complexity within food materials at micro and nanoscale. Fresh techniques like atomic force microscopy (AFM), confocal laser scanning microscopy (CLSM) and cryo-transmission electron microscopy (cryo-TEM) are developed for studying structural biology and imaging nanostructure and microstructure of foods.

AFM provides insight at the topography of a food surface at a very high-resolution and under the atmospheric conditions. AFM technique also serves the purpose of an alternative to measuring the forces of componential interactions at a nanoscale level. In contrast to other techniques, AFM offers to sample images via the advanced mode of tapping; the method uses an oscillating probe to scan the materials’ surface without coming into direct contact with the subject. This trait enables the study of soft materials that are prone to serious damage if imaged with conventional means.

CLSM technique has also established significant attention in the study of microstructures in foods. CLSM can follow the minute structural differences in foods that are conditioned to the dynamic conditions externally. The major benefit of CLSM technique over its counterparts is its ability to image thin, high-resolution images of foods. These CLSM rendered images can be used to generate 3D images via specialized software. Aguilera et al., (2005) noted that components of complex foods matrices acquiescent to fluorescence labeling could be envisaged via CLSM. Additionally, food structures, componential spatial orientation can be visualized with the use of varied fluoro-chromophores. CLSM technique has been used for identifying starch granules channels, the availability of proteins in the channels, and Sorghum’s Kafirin protein structure.

Food microstructures have also been studied with the use of acoustic waves scattering technique. McClements (1995) applied the acoustic technique to study physicochemical properties, food structures, and food flow behavior. The study demonstrated that food structure information could be grasped via low-intensity ultrasound. On the other hand, the structures can be altered with the use of ultrasound with high intensity. Lee et al., (2004) studied orange juice freezing by low-intensity ultrasound, Konrad et al., (1998) studied hydrocolloids material gelling, and the structure and properties of wheat dough (Lee et al., 2004). Lee et al. (2004) the structural change in orange juice while freezing with the application of Fourier Transformation- based means resembling wavelet. Ultrasound was used to study microstructure, macrostructure, and mechanism of agar gels (Ross et al. 2006). On the other hand, Strybulevych et al. (2007) demonstrated that ultrasounds could be brought to play in the determination of bubble sizes in aerated agar gels and beads. He also concluded that the measurement of bubble sizes is far superior to the optical means of measurement. Ultrasounds technique can also be employed to study the structures of opaque materials.

While the applications of scattering techniques are limited to the liquid system to imaging food microstructures, the means can provide quantitative values about the particles distribution of size included in the microstructure preferably for emulsion systems. The methods are rooted in a radiation beam’s scattering with the particles available in the sample. Distinct particle structure and sizes can be distinguished depending on the radiation nature (neutron, x-ray, light). Scattering methods offer a quick and simple evaluation of the structure and size of particles in a food system. However, they do not agree to the structural visualization. Therefore, they are primarily used to evaluate different food polysaccharides and proteins, as well as, the different processing conditions and behavior.

Conclusion

Material sciences are one of the newly emerged fields of study. It has multiple fields of application. Food is one of them. this assignment is about the food material sciences approach to describe the digestive process. The effect of material sciences on food and food industry especially related to the digestive process of the food and how material sciences are applicable to it are discussed here. Food particles and structures play an important role in the digestion process. The smallest the particle the more digestible it is. Similarly, the complex food particle structures are hard to digest. Different new technologies like nanotechnology are widely used in order to make food more digestible. Encapsulation, phase transition, gel structures and interfacial properties of food components are the key factors in digestibility. Different advance techniques are used to identify and analyse their effect on the process of digestion.

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