Support material plays a leading role in the application of 3D printing to avoid deformation and enhance stability. This study aimed to fabricate the support structure by using hydroxypropyl methylcellulose (HPMC), which has advantages over conventional material such as low cost, low printable temperature, and high biodegradability. Once dissolved in water over gelling temperature, the HPMC based hydrogel exhibited shear-thinning behavior with decreasing apparent viscosity values at higher shear rates. The shear-dependent viscosity makes the HPMC hydrogel extrudable throughout the printing process and the printed structure stable enough without deformation. As concentration increased, apparent viscosity, and storage modulus both subsequently increased. These rheological properties indicated that the concentration of HPMC K4M hydrogel significantly influenced the printability and shape retention ability, which is associated with the mechanical strength of printed filaments. The highest concentration, 12% w/v, should have the best ability to hold the printed shape over time due to the highest G' and lowest loss tangent. The printability test also showed that K4M 12% w/v could be printed into different fill density (100, 75, and 50%) with different patterns, i.e., rectilinear and Hilbert curve. The selection of fill density and pattern both have an effect on surface roughness and porosity. The printed support material was compatible with acrylonitrile butadiene styrene (ABS), which is the material to fabricate the main structure for 3D printing. The support material made of HPMC can be easily removed by peeling off from the main structure without visible residual.
This research explored the effects of using Accentuated Cut Edges (ACE) and macerating enzymes on the aroma and sensory profile of Marquette red wines after nine months of aging. The aroma analysis was conducted using gas chromatography-mass spectrometry (GC-MS) with solid-phase microextraction (SPME). The intensity of basic sensory attributes, including color, aroma, taste, and mouthfeel, were evaluated by eight trained panelists through descriptive analysis using 15 cm line scales. ACE treatment affected the aroma compounds profile, as suggested by the increased response ratio of ethyl butanoate, ethyl 2-methylpropanoate, and ethyl 3-methylbutanoate. Statistically, it significantly intensified honey (by 1.6 times) and green apple (by 2.1 times) notes, as perceived by panelists, compared to the control during the sensory descriptive analysis. Regardless of the type of enzymes, combined ACE and enzymes treatment amplified the color intensity of wine by up to 71.4% as observed by panelists, though this was not captured by spectrophotometric measurements (p > 0.05) from the previous study. A lower concentration of ester-derived compounds was found in ACE with enzymes wines, which was associated with the lower intensity of fruity notes during the descriptive analysis. Notably, none of the treatments affected astringency perception, likely due to the low concentration and small molecular weight of condensed tannins, alongside changes in the composition of soluble polysaccharide in Marquette red wines.