Exploring Environmental Settings to Improve the Printability of Paroxetine-Loaded Filaments by Fused Deposition Modelling

The successful integration of hot-melt extrusion (HME) and fused deposition modelling (FDM) depends on a better understanding of the impact of environmental conditions on the printability of formulations, since they significantly affect the properties of the raw materials, whose control is crucial to enable three-dimensional printing (3DP). Hence, the objective of this work was to investigate the correlation between the environmental settings and the properties of paroxetine (PRX)-loaded filaments, previously produced by HME, which affect printability by FDM. The influence of different drying methods of the physical mixtures (PMs) and HME-filaments (FILs) on the quality and printability of these products was also assessed. The printability of FILs was evaluated in terms of the water content, and the mechanical and thermal properties of the products. Stability studies and physicochemical, thermal, and in vitro dissolution tests were carried out on the 3D-printed tablets. Stability studies demonstrated the high ductility of the PRX loaded FILs, especially under high humidity conditions. Under low humidity storage conditions (11% RH), the FILs became stiffer and were successfully used to feed the FDM printer. Water removal was slow when carried out passively in a controlled atmosphere (desiccator) or accelerated by using active drying methods (heat or microwave). Pre-drying of the PRX/excipients and/or PMs did not show any positive effect on the printability of the FIL. On the contrary, dry heat and, preferably, microwave mediated drying processes were shown to reduce the holding time required for successful FDM printing, enabling on-demand production at the point of care.

Effect of different types of electrolyzed water on drying characteristics and quality of Spondias dulcis in oven drying

Due to its less adverse impact on the environment as well as human health, electrolyzed water, a non-thermal method, has been recognized to be a promising alternative as a new disinfectant for the food industry, which does not change odor, texture, and flavor of foods. Spondias dulcis fruit is rich in bioactive compounds, vitamins and minerals, which are known to have many beneficial effects on health. Fresh S. dulcis has a short shelf life and drying is an option to preserve the fruit. In this study, the effects of electrolyzed water treatment on the quality characteristics of dried S. dulcis were investigated. Slices of fruit treated with four different electrolyzed waters (Anolyte NaCl, Catholyte NaCl, Anolyte Na2CO3, and Catholyte Na2CO3) were dried in a conventional oven at 70 °C. Color, Browning index, antioxidant characteristics, texture profile, rehydration capacity, pH, and Fourier transform infrared spectroscopy analyzes of dried S. dulcis were performed. The samples treated with electrolyzed water prior to drying showed higher antioxidant activity (59.46 ± 0.09), total phenolic content (287.00 ± 1.76), and rehydration capacity (4.52 ± 0.05) compared to the control samples. The findings of the current study showed that electrolyzed water treatment could prevent the browning of dried S. dulcis fruits and preserve bioactive compounds as well as chemical properties.

Comparison of the Calcium Carbide Method and Darr Drying to Quantify the Amount of Chemically Bound Water in Early Age Concrete

Hydration is the exothermic reaction between anhydrous cement and water, which forms the solid cement matrix of concrete. Being able to evaluate the hydration is of high interest for the use of both conventional and more climate-friendly building materials. The experimental monitoring is based on temperature or moisture measurements. The first needs adiabatic conditions, which can only be achieved in laboratory. The latter is often measured comparing the weight of the material sample before and after oven drying, which is time-consuming. This study investigates the moisture content of two cement-based and two calcium sulphate based mixtures for the first 90 days by using the calcium carbide method and oven drying at 40 °C and 105 °C (Darr method). Thereby, the amount of chemically bound water is determined to derive the degree of hydration. The calcium carbide measurements highly coincide with oven drying at 40 °C. The calcium carbide method is therefore evaluated as a suitable alternative to the time-consuming Darr drying. The prompt results are seen as a remarkable advantage and can be obtained easily in laboratory as well as in the field.

Effect of Drying Methods on Properties of Potato Flour and Noodles Made with Potato Flour

This work investigated the impact of three drying methods on structural and functional properties of potato flour (PF), as well as the quality characteristics of fresh noodles made from wheat-potato flours. The results indicated that ethanol drying (ED) and oven drying (OD) had small effects on the properties of starch in potato flour, however, freeze drying (FD) caused some pores and channels on the starch granules and disruption of the long- and short-range ordered structure of starch. The maximum addition of potato flour in fresh noodles was 40% for FD-PF and 50% for both ED-PF and OD-PF. With increasing addition of potato flour in noodles, the L* (lightness) values of noodles decreased gradually, while the a* (redness) and the b* (yellowness) values, as well as the hardness and springiness values of fresh potato noodles increased. This study clearly showed that drying methods have different effects on the properties of potato flour, and in turn the quality of fresh noodles made with potato flour.

Lack of interactive effects between diet composition and acid addition with drying method on amino acid digestibility values in porcine ileal digesta

Two experiments were conducted to determine the effect of oven drying (OD) or freeze drying (FD) on apparent ileal digestibility (AID) of AA in diets fed to pigs. In experiment 1, 15 barrows (88.4 ± 6.4 kg) were allotted to either a corn starch-soybean meal (CST), potato starch-soybean meal (PST), or corn-soybean meal (CSBM) diet, over 2 collection periods. Following collection, samples were pooled within pig and subdivided into either OD or FD, resulting in 10 observations per diet by drying-method combination. In experiment 2, 11 barrows (63.3 ± 3.8 kg) were fed a CST diet, and, following collection, samples were pooled within pig and subdivided and either adjusted to pH 4 or remain unadjusted. Subsets of these samples were then subdivided to be either FD or OD, resulting in 11 observations per pH level by drying-method combination. OD was accomplished by drying samples in a forced air oven at either 100 °C (experiment 1) or 75 °C (experiment 2). In experiment 1, there was no diet type by drying-method interactions noted for any of the AA (P > 0.10).OD resulted in a higher AID of AA compared with samples which were FD (P ≤ 0.10), for all AA except for Gly and Tyr. Averaged across all AA, AID of AA was 3.3% greater if the sample was OD compared with FD. Differences in AID of AA among the 3 diets were noted for all AA (P ≤ 0.07), except for Cys (P = 0.33), due to the fact that CST and PST diets only contained soybean meal (SBM) as an AA-providing ingredient while the CSBM diet contained both corn and SBM. Pigs fed the PST diet had greater SID for all AA compared with pigs fed the CST diet (P ≤ 0.05), except for His, Lys, Cys, and Glu. In experiment 2, there were no pH-adjustment by drying-method interactions noted on AID for any of the AA (P > 0.10). Adjusting ileal digesta to a pH of 4.0 had little effect on AID for most of the AA, except for a lowered AID of Arg, His, Lys, Trp, and Ser (P ≤ 0.10). OD resulted in a higher AID for all AA (P ≤ 0.09) except for Ile, Thr, Val, Ala, Asp, Glu, and Gly. Averaged across all AA, the increase in AID of AA was 1.7% greater if the sample was OD compared with FD. On average, OD of ileal digesta resulted in a 2.5% greater estimate of AID of AA compared with samples that were FD, and was not diet-, pH-, or AA-dependent. Because the majority of the data on AA digestibility are based on FD, a bias factor may be necessary to adjust AA digestibility data obtained on an OD-basis relative to an FD-basis for use in feed formulation.

Impact of drying methods on composition and functional properties of date powder procured from different cultivars

The present study was designed to evaluate the effect of two different drying methods, that is, spray drying and oven drying on physicochemical and nutritional attributes of date flesh powder of dhakki, aseel, and rabi varieties. Date powders were prepared using mixture of maltodextrin and acacia gum (50:50) as drying aid at the rate of 0.4 kg per 1.0 kg of date fruits (dry weight basis). The oven-drying conditions were 60°C for 48 hr, whereas in spray drying, flow rate of 30 ml/min at 150°C was maintained. Date powder was obtained in both treatments from three varieties. Nutritional profile in all six powders was explored specifically with quantification of sugars using HPLC-RI, followed by physicochemical characterization. The total phenolic compounds, color (L*a*b* values), hygroscopicity, bulk density, wettability, solubility index, and glass transition temperatures (using differential scanning calorimetry, DSC), were determined for the date powders. The nutritional profile and total phenolic contents and sugars (sucrose, fructose, and glucose) were significantly different for the varieties, while treatments showed insignificant effect. The physicochemical characteristics of date powder varied significantly with respect to the date varieties. The colored values were affected due to treatments also, and the spray-dried powders showed better color values. The drying methods also showed effects in some parameters such as wettability time. Similarly, bulk density was different in both treatments for rabi and aseel. The glass transition temperatures were significantly varied in varieties due to difference in sugar contents, but within the treatments, they remain unaffected. The highest glass transition temperature of spray-dried rabi was 53.2 ± 1.31°C.

Short communication: Effects of drying and analytical methods on nitrogen concentrations of feeds, feces, milk, and urine of dairy cows

Nitrogen concentrations in feeds, feces, milk, and urine samples were measured using 2 analytical methods following different drying procedures. Ten samples of corn silage, alfalfa silage, and concentrates collected from 2017 to 2018 at Krauss Dairy Research Center, The Ohio State University (Wooster), were used. A 4-d total collection digestion trial provided fecal samples from 10 cows (1 sample/cow), and another 10 cows were used to collect milk samples (1 sample/cow) and spot urine samples (1 sample/cow). Spot urine samples were acidified immediately to pH <3.0 when collected. Feed samples were oven dried (55°C) or lyophilized and analyzed using the Kjeldahl (KJ; copper sulfate as a catalyst) method and a combustion method (elemental analyzer; EA). Feces, urine, and milk samples were analyzed for N using the following methods: (1) fresh samples by KJ (referred to as wet KJ), (2) lyophilization (urine and milk for 8 h; feces for 120 h) followed by EA (LYO-EA), and (3) oven drying (milk and urine for 1 h; feces for 72 h at 55°C) followed by EA (OD-EA). Additionally, changes in N content of acidified urine at -20° over 180 d of storage were examined. Nitrogen concentrations in corn silage, alfalfa silage, and concentrates were greater for EA by 6.1, 4.8, and 8.3%, respectively, compared with KJ. Analysis of dried samples via EA compared with wet KJ resulted in lower fecal N content (27.8 vs. 29.3 g/kg of DM). Nitrogen concentration in fecal samples via KJ after lyophilization was lower by 5% compared with wet KJ but did not differ from LYO-EA, suggesting that N losses occurred during drying. Nitrogen determination with EA after drying of samples resulted in greater milk N (5.70 vs. 5.50 g/kg) and urinary N (9.16 vs. 9.06 g/kg) content compared with wet KJ. However, drying method (i.e., lyophilization vs. oven drying) did not affect N content of milk, urine, or feces. The use of EA resulted in lower percentage deviation of N content from duplicate sample assays for most samples (no difference was found for concentrate and fecal N), suggesting that EA was more precise than KJ. In conclusion, drying of feces caused N losses regardless of drying methods. For urine and milk samples, if drying is necessary (i.e., EA), oven drying at 55°C can be used rather than lyophilization. The N content was greater in feeds, milk, and urine when determined with EA versus KJ. In addition, N content in acidified and undiluted urine at -20° changed and should be analyzed within 90 d of storage. The results in the current study, however, did not account for laboratory-to-laboratory variation.

Oven drying of ileal digesta from growing pigs reduces the concentration of AA compared with freeze drying and results in reduced calculated values for endogenous losses and elevated estimates for ileal digestibility of AA

Two experiments were conducted to evaluate the influence of drying method on the composition of ileal digesta and the standardized ileal digestibility (SID) of CP and AA in feed ingredients fed to pigs. The hypothesis was that oven drying of ileal digesta samples results in loss of N and AA, and therefore, in greater calculated values for SID of CP and AA compared with lyophilized samples. In Exp. 1, eight barrows (13.8 ± 0.5 kg BW) were equipped with a T-cannula in the distal ileum and randomly allotted to a replicated 4 × 4 Latin square design with four diets and four periods, for a total of eight replicate pigs per diet. Three diets containing three different sources of soybean meal as the sole source of AA and an N-free diet were used. In Exp. 2, 18 cannulated growing barrows (72.5 ± 9.2 kg BW) were allotted to a completely randomized design with three diets and six replicate pigs per diet. The three diets included two diets based on two sources of distillers dried grains with solubles and an N-free diet. In both experiments, ileal digesta samples were collected for 8 h on days 6 and 7 of the 7-d feeding period. At the conclusion, two representative sub-samples were collected from each ileal digesta sample. One sub-sample was lyophilized and the other was oven dried at 60 °C using a forced air oven. Results indicated that in both experiments, DM was greater (P < 0.05) in lyophilized samples than in oven dried samples. There was no difference in the SID of CP between the two drying methods. However, except for Ala and Val in Exp. 1, the concentration of AA (88% DM-basis) was greater (P < 0.05) in lyophilized samples than in oven dried samples, which resulted in reduced calculated values for basal endogenous losses of AA. Therefore, values for the SID of AA (except for Ala in Exp. 1 and Trp and Gly in Exp. 2) were greater (P < 0.05) when calculated from oven dried samples than from lyophilized samples. In conclusion, regardless of the diet, oven drying of ileal digesta samples does not result in loss of N, but appears to damage or convert AA to other N-containing compounds, which results in reduced estimates for basal endogenous losses and greater calculated values for SID of AA. Thus, freeze drying of ileal digesta samples is recommended when data for the SID of AA are calculated for feed ingredients fed to pigs.

Thin-layer drying behavior of West Indian lemongrass (Cymbopogan citratus) leaves

The objectives of this study were to investigate the effect of temperature (40, 50, 60, and 70°C), and air velocity (0.5, 1, and 2 m/s) on the drying behavior of West Indian lemongrass (Cymbopogan citratus) leaves. Drying was carried out in a computer-controlled tray dryer. Overall, the effect of temperature was seen to be more important than that of air velocity, but the air velocity did have an effect on drying rates at the start of the drying process at 50-70°C. Drying rate constants, diffusivity values, and activation energy were determined. Twenty-two empirical and semiempirical thin-layer models were tested, and although model fit varied, the Midilli model could be applied to all data with reasonable prediction of MR values.