Temperature controlled cryoprinting of food for dysphagia patients

Authors: LOU, LEO - University Of California Berkeley; Bilbao-Sainz, Cristina; Wood, Delilah - De; RUBINSKY, BORIS - University Of California Berkeley

Submitted to: Innovative Food Science and Emerging Technologies
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/8/2023
Publication Date: 4/11/2023
Citation: Lou, L., Bilbao-Sainz, C., Wood, D.F., Rubinsky, B. 2023. Temperature controlled cryoprinting of food for dysphagia patients. Innovative Food Science and Emerging Technologies. 86. Article 103362. https://doi.org/10.1016/j.ifset.2023.103362.
DOI: https://doi.org/10.1016/j.ifset.2023.103362

Interpretive Summary: Dysphagia is a medical condition associated with difficulty swallowing food that affects one in six adults in the United States. The incidence increases with age, with an estimated 10% to 30% of those older than 65 years affected. Currently, dysphagia patients are limited to foods which include purees, minced or small bite-size forms or liquids. Often, these foods are visually and textural unappetizing and nutritionally deficient. 3D Temperature Controlled Cryoprinting (TCC) technology, originally developed for tissue engineering, was used to manufacture 3D printed beef slices suitable for people with dysphagia. The key feature of TTC is temperature-controlled freezing of 3D printed voxels to control the microscale structure of ice in the printed object, resulting in the generation of anisotropic structures which confer texture to the printed beef slices. These beef slices display the largest anisotropy ratio, reduced adhesiveness and cohesiveness and require less mastication effort (chewiness, gumminess) while keeping the initial bite tenderness (shear force) and hardness within the safe range for dysphagia foods. In addition, the printed beef slices satisfy International Dysphagia Diet Standardization Initiative requirements as level 6 foods for dysphagia patients.

Technical Abstract: 3D Temperature Controlled Cryoprinting (TCC) employed temperature-controlled freezing to generate desired ice crystal microstructures in each individual printed voxel element to form a cryo-printed bioproduct with intended microstructure. This was the first study using TCC technology to create a food product. This study investigated the influence of printing, cross-linking order, and directional freezing rates on the microstructure, viscoelastic and textural properties of the resulting 3D TCC beef. Scanning electron microscopy images showed that when directional freezing occurred before cross-linking, the microstructure consisted of alternating ridges of beef material with elongated pores parallel to the freezing direction. Shear stress tests also confirmed that the 3D printed meat had textural anisotropy. All TCC beef samples showed solid-like behavior. The International Dysphagia Diet Standardization Initiative tests revealed that the ink could be classified a level 4 (pureed) food, whereas the 3D TCC samples could be categorized as level 6 (soft and bite-sized) foods. Industrial relevance: 3D TCC technology could be used to manufacture frozen foods with anisotropic microstructures to impart texture to 3D printed foods. These frozen foods, when thawed, had visual and textural resemblance to everyday food. Also, the 3D TCC technology allowed a one-step process to manufacture and freeze foods.