Improving the textural and nutritional properties in restructured meat loaf by adding fibers and papain designed for elderly.

This study aimed to evaluate the effects of dietary fibers (apple, oat, pea, and inulin) in meat loaves treated with papain enzyme. In the first step, dietary fibers were added to the products at the level of 6%. All dietary fibers decreased the cooking loss and improved the water retention capacity throughout the shelf life of the meat loaves. Besides, the dietary fibers increased the compression force of meat loaves treated with papain, mainly oat fiber. The dietary fibers decreased the pH, especially the treatment with apple fiber. In the same way, the color was changed mainly by the apple fiber addition, resulting in a darker color in both raw and cooked samples. TBARS index increased in meat loaves added with both pea and apple fibers, mostly for the last one. In the next step, the combination of inulin, oat, and pea fibers was evaluated in the meat loaves treated with papain, combining fibers up to 6% total content likewise decreased cooking and cooling loss and increased the texture of the papain-treated meat loaf. The addition of fibers improved the acceptability of the texture-related samples, except for the three-fiber mixture (inulin, oat, and pea), which was related to a dry, hard-to-swallow texture. The mix of pea and oat fibers conferred the best descriptive attributes, possibly related to improved texture and water retention in the meat loaf, and comparing the use of isolated oat and pea, the perception of negative sensory attributes was not mentioned, such as soy and other off-flavors. Considering these results, this study showed that dietary fibers combined with papain improved the yielding and functional properties with potential technological use and consistent nutritional claims for elderly.

Polymeric Materials, Advances and Applications in Tissue Engineering: A Review.

Tissue Engineering (TE) is an interdisciplinary field that encompasses materials science in combination with biological and engineering sciences. In recent years, an increase in the demand for therapeutic strategies for improving quality of life has necessitated innovative approaches to designing intelligent biomaterials aimed at the regeneration of tissues and organs. Polymeric porous scaffolds play a critical role in TE strategies for providing a favorable environment for tissue restoration and establishing the interaction of the biomaterial with cells and inducing substances. This article reviewed the various polymeric scaffold materials and their production techniques, as well as the basic elements and principles of TE. Several interesting strategies in eight main TE application areas of epithelial, bone, uterine, vascular, nerve, cartilaginous, cardiac, and urinary tissue were included with the aim of learning about current approaches in TE. Different polymer-based medical devices approved for use in clinical trials and a wide variety of polymeric biomaterials are currently available as commercial products. However, there still are obstacles that limit the clinical translation of TE implants for use wide in humans, and much research work is still needed in the field of regenerative medicine.

Evaluating different levels of papain as texture modifying agent in bovine meat loaf containing transglutaminase.

In this study, bovine meat loaves were produced with different levels of papain (0.00125%, 0.0025%, 0.00375%, and 0.005%) combined with transglutaminase (1%). The effect of this reformulation on pH, instrumental color, water activity, proximate composition, texture, yield, and scanning electron microscopy (SEM) of meat loaves was investigated. In addition, the enzymatic activity of papain was also analyzed. The papain addition increased the pH and the yield of the samples. The hardness was progressively reduced with the increase of papain level. Such changes could be seen through the images recorded by SEM, where an extremely fragmented structure was observed in treatments with higher papain concentration. Papain showed an optimum temperature of 80 °C. This study allowed to observe an intense proteolytic effect in all treatments, despite the papain concentration. Therefore, lower levels should be applied so that the product does not alter its sensory characteristics, such as soft and crumbly texture.

Interaction between papain and transglutaminase enzymes on the textural softening of burgers.

The present study investigated the effect of the enzymes papain (0.2%) and microbial transglutaminase (MTG) (1%) on the texture properties of beef and chicken burgers to develop a meat product with significant increase in softness due to the physiological limitations of the elderly. The products were characterized for pH, objective color, water activity, texture profile analysis (TPA), shear force, compression test, electrophoretic profile, cooking loss, and diameter reduction. A pronounced increase in softness was observed for both raw materials containing papain. An increase in shear force was observed for the beef burger containing only MTG, while the chicken burger showed a reduction of this parameter. The compression tests showed papain alone or combined with MTG decreased the hardness of the burgers. The results showed that the combination of the enzymes papain and MTG can be an effective strategy to develop beef and chicken burgers much softer, contributing to the future studies focused on the physiological needs of the elderly.

Advances in additive manufacturing for bone tissue engineering scaffolds.

This article reviews the current state of the art of additive manufacturing techniques for the production of bone tissue engineering (BTE) scaffolds. The most well-known of these techniques include: stereolithography, selective laser sintering, fused deposition modelling and three-dimensional printing. This review analyses in detail the basic physical principles and main applications of these techniques and presents a list of biomaterials for BTE applications, including commercial trademarks. It also describes and compares the main advantages and disadvantages and explains the highlights of each additive manufacturing technique and their evolution. Finally, is discusses both their capabilities and limitations and proposes potential strategies to improve this field.

Controlled degradability of PCL-ZnO nanofibrous scaffolds for bone tissue engineering and their antibacterial activity.

Up to date, tissue regeneration of large bone defects is a clinical challenge under exhaustive study. Nowadays, the most common clinical solutions concerning bone regeneration involve systems based on human or bovine tissues, which suffer from drawbacks like antigenicity, complex processing, low osteoinductivity, rapid resorption and minimal acceleration of tissue regeneration. This work thus addresses the development of nanofibrous synthetic scaffolds of polycaprolactone (PCL) - a long-term degradation polyester - compounded with hydroxyapatite (HA) and variable concentrations of ZnO as alternative solutions for accelerated bone tissue regeneration in applications requiring mid- and long-term resorption. In vitro cell response of human fetal osteoblasts as well as antibacterial activity against Staphylococcus aureus of PCL:HA:ZnO and PCL:ZnO scaffolds were here evaluated. Furthermore, the effect of ZnO nanostructures at different concentrations on in vitro degradation of PCL electrospun scaffolds was analyzed. The results proved that higher concentrations ZnO may induce early mineralization, as indicated by high alkaline phosphatase activity levels, cell proliferation assays and positive Alizarin-Red-S-stained calcium deposits. Moreover, all PCL:ZnO scaffolds particularly showed antibacterial activity against S. aureus which may be attributed to release of Zn2+ ions. Additionally, results here obtained showed a variable PCL degradation rate as a function of ZnO concentration. Therefore, this work suggests that our PCL:ZnO scaffolds may be promising and competitive short-, mid- and long-term resorption systems against current clinical solutions for bone tissue regeneration.

Efficacy of atelocollagen honeycomb scaffold in bone formation using KUSA/A1 cells.

To induce new bone formation, mesenchymal stem cells were seeded onto atelocollagen honeycomb scaffold. We evaluated the efficacy of this scaffold combined with KUSA/A1 cells in vivo. KUSA/A1 cells alone and with atelocollagen were implanted in the subcutaneous pockets of 4-week-old male SCID mice. The transplants were subjected to radiographical, histological, and immunohistochemical examinations after 2 and 4 weeks of implantation. Radiographically, both KUSA/A1 cells alone and KUSA/A1-atelocollagen showed some radiopaque areas formation but the latter disclosed a larger amount. Histologically, KUSA/A1 cells alone showed few small islands of new bone formation surrounded by a thin layer of cellular proliferation. On the other hand, KUSA/A1-atelocollagen revealed abundant new bone formation as well as cellular proliferation. We also determined the immunolocalization of type I collagen, CD34, osteocalcin, osteopontin, and PCNA in this newly formed bone. Our results indicated that collagen scaffold plays an important role allowing vessel formation and cell anchorage, especially through the proliferation and differentiation process in a confined space. This study supports tissue engineering as an alternative for treating different target diseases, such as trauma or congenital defects, and enhances existing therapeutic applications.