Search Results (2,464)

Organic dairy products, including fermented milk, are gaining popularity among consumers. Traditionally, for kefir production, kefir grains are used; however, in the modern industry, freeze-dried cultures are commonly employed. This study aimed to analyze the quality of kefirs produced from organic cow milk with two fermentation times (12 and 24 h) with the use of kefir grains or freeze-dried culture. During a 3-week storage period, physicochemical properties, color, syneresis index, texture, sensory, and microbiological quality were evaluated. The results proved that organic cow milk was suitable for kefir production both with the use of kefir grains and freeze-dried culture. Using freeze-dried culture and a 24 h fermentation period resulted in kefir with the lowest syneresis tendency (3.65–9.62%), along with the best textural properties (the highest cohesiveness and viscosity index), and desired sensory characteristics. Kefir grains had a better acidification ability, and the resulting products had a higher count of yeasts, lactobacilli, and lactococci compared with kefirs obtained with freeze-dried culture. However, both the type of starter culture and the fermentation time influenced the product’s quality. The longer fermentation time of 24 h was more appropriate for the kefir production. Kefir grains, as a traditional form of kefir culture, may be preferred in organic kefir production. Full article

The effective and safe treatment of red mud has become a pressing global issue in recent years. The purpose of this study is to prepare different systems of low-carbon cementitious materials by combining various solid wastes (slag powder, red brick of construction waste) with different systems of low-carbon cementitious materials and to observe the effects of different cementitious compositions on the construction performance, mechanical properties, freeze–thaw resistance, and heavy metal leaching properties by designing different systems of low-carbon cementitious materials, as well as to analyze the microscopic morphology, mineral composition, and strength-forming mechanisms of the different systems of low-carbon cementitious materials through the use of X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The findings reveal that a ternary cementitious system containing 16% red brick powder exhibits the most favorable overall performance. Compared to a binary system, this mixture improves fluidity by 4.5%, increases compressive strength by 18.27%, reduces drying shrinkage by 39.56%, and lowers the mass loss rate during dry–wet cycling by 11.07%. Furthermore, the leaching levels of heavy metals such as Cr, As, Pb, Ni, and Cu in the red mud-based cementitious materials, combined with multiple solid wastes, are within the safe limits for non-hazardous environmental release, as specified by Chinese regulations, under both freeze–thaw and non-freeze–thaw conditions. This study demonstrates for the first time the potential of combining red mud with construction waste brick dust and provides a scientific basis and theoretical guidance for the synergistic utilization of alkaline solid waste, calcium solid waste, and silica–aluminum solid waste. Full article

Stems are a major by-product of mushroom production. This study optimizes the transformation of Agaricus bisporus stems (ABS) and Pleurotus ostreatus stems (POS) into flour. ABS are attached to the peat, so, the process was divided into two steps. First, four cleaning methods were tested for ABS: pre-drying, brushing, abrasive peeling, and immersion in chlorinated water and brushing. Abrasive peeling was the most effective, showing the lowest color difference (9.18), total aerobic count (3.48 log cfu/g), and the highest profitability (1 kg/h). In the second step, ABS and POS were dried using a freeze-dryer, a dehydrator, and an oven. Dehydration resulted in stems with a lower browning index (24.57 in ABS and 29.95 in POS) than the oven, and a smaller energy consumption than the freeze-dryer. Finally, three dehydration temperatures (40, 50, and 60 °C) were compared. Dehydration at 50 °C resulted in faster moisture loss (24 h) and similar phenolic compound concentrations (3.35 and 7.69 mg GAE/100g fresh ABS and POS, respectively) than at 40 °C (32 h in ABS and 28 h in POS). In conclusion, the transformation of ABS and POS into flours requires processes that influence their chemical composition, physicochemical characteristics, and the profitability of their production. In this project, the optimal process involved cleaning ABS through abrasive peeling and dehydrating both ABS and POS at 50 °C for 24 h. Full article

Background/Objectives: This study aimed to develop a novel nanotechnological slow-release drug delivery platform based on hyaluronic acid Microsponge (MSP) for the subcutaneous administration of methotrexate (MTX) in the treatment of rheumatoid arthritis (RA). RA is a chronic autoimmune disease characterized by joint inflammation and damage, while MTX is a common disease-modifying antirheumatic drug (DMARD), the conventional use of which is limited by adverse effects and the lack of release control. Methods: MSP were synthesized as freeze-dried powder to increase their stability and allow for a facile reconstitution prior to administration and precise MTX dosing. Results: A highly stable and rounded-shaped micrometric MSP, characterized by an open porosity inner structure, achieved both a high MTX loading efficiency and a slow release of MTX after injection. Our drug release assays indeed demonstrated a characteristic drug release profile consisting of a very limited burst release in the first few hours, followed by a slow release of MTX sustained for over a month. By means of a preclinical rat model of RA, the administration of MTX-loaded MSP proved to nearly double the therapeutic efficacy compared to sole MTX, according to a steep reduction in arthritic score compared to control groups. The preclinical study was replicated twice to confirm this improvement in performance and the safety profile of the MSP. Conclusions: This study suggests that the MSP drug delivery platform holds significant potential for clinical use in improving RA therapy by enabling the sustained slow release of MTX, thereby enhancing therapeutic outcomes and minimizing side effects associated with conventional burst-release drug administration. Full article

The current study focused on sourdough breads produced with various supplements consisting of freeze-dried black chokeberry juice, (i) unfermented and (ii) fermented by Lactiplantibacillus paracasei SP5, aiming to enhance their functionality and nutritional value. Specifically, the impact of these supplements on the quality of sourdough breads was evaluated in terms of their nutritional features, antimicrobial capacity, and sensorial characteristics. Sourdough breads produced with freeze-dried fermented chokeberry juice exhibited elevated concentrations of lactic acid (2.82–2.99 g/kg) and acetic acid (0.93–0.99 g/kg), which significantly prolonged their resistance to mould growth and rope contamination, maintaining freshness for over 13 days. These samples also demonstrated higher antioxidant activity, with DPPH values exceeding 4 μmol TE/g and ABTS values surpassing 218 mg TE/100 g, along with a total phenolic content ranging from 85.9 to 96.3 mg GAE/100 g. Additionally, these samples showed a greater reduction in phytate, an antinutrient, compared to all other samples, including the control. The sensory evaluation conducted with consumer panels indicated that sourdough breads prepared with freeze-dried fermented chokeberry juice achieved the highest ratings in terms of taste and appearance among all tested samples. The findings are highly promising and suggest the potential for commercializing the developed supplements in the production of additive-free sourdough bread with enhanced nutritional value. Full article

Flexible wearable sensors have obtained tremendous interest in various fields and conductive hydrogels are a promising candidate. Nevertheless, the insufficient mechanical properties, the low electrical conductivity and sensitivity, and the limited functional properties prevent the development of hydrogels as wearable sensors. In this study, an SFMA/BAChol/PAA/ZnCl₂ hydrogel was fabricated with high mechanical strength and versatile comprehensive properties. Specifically, the obtained hydrogel displayed excellent adhesion and mechanical stability, cryophylactic ability, stable sensitive freezing-tolerant conductivity, and feasible electrical conduction under a wide temperature range, demonstrating the high application potential as a flexible wearable sensor for movement behavior surveillance, even under harsh environments. Furthermore, the mechanical strength of the hydrogel could easily be regulated by varying the copolymer content. The molecular mechanisms of the hydrogel formation and the reversible adhesion during the wet-dry transition were proposed. The non-covalent interactions, including the electrostatic interaction, hydrogen bond interaction and hydrophobic association, and coordination interaction, were dynamically presented in the hydrogel network and hence supported the versatile comprehensive properties of the hydrogel. This study provides a strategy for designing novel hydrogels to promote the development of flexible sensors with stable sensitive freezing-tolerant conductivity. Full article

Celecoxib (CEL), a nonsteroidal anti-inflammation drug (NSAID), is categorized as a Class II drug (low solubility, high permeability) in the Biopharmaceutics Classification System (BCS). The aim of this study is to develop a novel formulation of CEL nanosuspensions in the form of dried powder for tableting or capsuling. In this study, CEL was formulated into nanosuspensions to improve its solubility. CEL nanosuspensions were prepared using the precipitation method followed by high-pressure homogenization. Drying of the nanosuspensions was performed by spray drying and freeze drying. We examined the impact of various formulation and processing parameters on the nanoparticles. The CEL nanoparticles were characterized by particle size analysis, differential scanning calorimetry (DSC), powder X-Ray diffraction (PXRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and dissolution tests. The choice of solvent, stabilizer, and surfactant appeared to have significant impacts on the crystallization and particle size and, consequently, the solubility of the CEL nanoparticles. CEL chemical stability was maintained throughout both drying processes. Both spray-dried and freeze-dried CEL nanosuspensions showed rapid dissolution profiles compared to raw CEL due to the nanosized particle dispersion with the presence of a lag phase. The freeze-dried nanosuspension showed a slight delay in the first 20 min compared to the spray-dried nanosuspension, after which dissolution progressed with a lag phase that represents aggregation. Full article

Comprehensive analysis of the lipid content in Cordyceps sinensis samples is essential for optimizing their effective use. Understanding the lipid profile can significantly enhance the application of this valuable fungus across various fields, including nutrition and medicine. However, to date, there is limited knowledge regarding the effects of different drying methods on the quality of lipids present in Cordyceps sinensis. In this study, we employed a broadly targeted lipidomic strategy to conduct a comprehensive analysis of the lipid composition in Cordyceps sinensis subjected to various drying methods. A comprehensive analysis identified a total of 765 distinct lipid species from fresh Cordyceps sinensis (FC), vacuum-freeze-dried Cordyceps sinensis (VG), oven-dried Cordyceps sinensis (OG), and air-dried Cordyceps sinensis (AG). Among these, glycerophospholipids (GP) were the most abundant, followed by glycerides (GL) and sphingolipids (SP). In this study, a total of 659 lipids demonstrated statistically significant differences, as indicated by a p-value (p) < 1. Among these lipids, triglycerides (TG) exhibited the highest concentration, followed by several others, including ceramide-ascorbic acid (Cer-AS), phosphatidylethanolamine (PE), lysophosphatidylcholine (LPC), and phosphatidylserine (PS). OG was the fastest drying method; however, PCA and OPLS-DA analyses indicated that the most significant changes in the lipids of Cordyceps sinensis were observed under the OG method. Specifically, 517 differentially accumulated lipids were significantly down-regulated, while only 10 lipids were significantly up-regulated. This disparity may be attributed to the degradation and oxidation of lipids. The metabolic pathways of glycerolipid, glycerophospholipid, and cholesterol are critical during the drying process of Cordyceps sinensis. This study provides valuable insights that can enhance quality control and offer guidelines for the appropriate storage of this medicinal fungus. Full article

Celery leaves account for 5–10% of the celery weight and are rich in nutrients, but they are usually discarded as waste. To explore this resource, hot-air drying (HA), intermittent hot-air drying (IHA-A and B), vacuum hot-drying and freeze-drying (VH and VF) were used to systematically investigate the effects of drying conditions on quality attributes, taste and volatile compounds of celery leaves. VF could better maintain the quality attributes, while IHA-B leaves were rich in taste and volatile components. The results indicated that both drying temperature and vacuum environment had significant effects on quality attributes. In terms of taste, reducing the drying temperature enriched the taste of celery leaves; however, in vacuum drying, the high temperature could contribute to increase the contents of total free amino acids and bitter amino acids. For volatile compounds, different drying conditions gave celery leaves different aromas, and IHA treatments resulted in a significantly higher content of volatile compounds than other treatments. Full article

This work demonstrates the preparation of fast-swelling hydrogels based on poly(vinyl alcohol) (PVA) and tamarind xyloglucan (XG), utilizing freeze-drying to achieve an interconnected macroporous structure. Although XG is non-toxic and abundant, it has poor mechanical properties. Therefore, XG was mixed with PVA and crosslinked with citric acid (CA). Without XG, the crosslinked PVA sample contained partially aligned channels several hundred microns wide. The addition of XG (25% w/w) reduced the structural order of the hydrogels. However, the addition of XG improved the swelling ratio from 308 ± 19% in crosslinked PVA to 533.33% in crosslinked PVA/XG. XG also increased the porosity, as the porosity of the crosslinked PVA, XG, and PVA/XG samples was 56.09 ± 2.79%, 68.99 ± 2.06%, and 66.49 ± 1.62%, respectively. Resistance to compression was decreased by the incorporation of XG but was increased by CA crosslinking. The determination of the gel fraction revealed that CA crosslinking was more effective for the PVA component than the XG component. The swelling of all hydrogels was very rapid, reaching equilibrium within 10 s, due to the interconnected macroporous structure that allowed for capillary action. In conclusion, the prepared hydrogels are non-cytotoxic and well suited for biomedical applications such as drug delivery, wound dressings, and hygienic products. Full article

The aim of this study was to assess the impact of tomato pomace (TP) on the content of volatile compounds and L-carnitine and the sensory characteristics of raw fermented sausages produced with reduced nitrite. The produced sausages were divided into three experimental groups: control sample, sample with 1.5% addition of freeze-dried tomato pomace, and sample with 2.5% addition of TP. The results showed that the addition of tomato pomace significantly affected the quality of raw fermented sausages. Lower L-carnitine content was observed in samples with TP. The main groups of volatile compounds identified in fermented sausages were alcohols, aldehydes, hydrocarbons, and ketones. The addition of TP influenced the smell and taste of the sausages, which were characterized by a more intense tomato taste and smell and more intense red color compared to the control sample. Despite the influence of TP addition on some sensory features, the products were characterized by a high score of overall quality of over 7 c.u. on a 10-point scale, similar to the control sausage. Full article

This study explores the impact of three bioadditives derived from Alfalfa—biomass, bio-ashes, and lyophilisates—on natural rubber composites, with a primary focus on the anti-aging properties of lyophilisates. Composite samples were prepared by incorporating these bioadditives into natural rubber and analyzed using various characterization techniques to evaluate mechanical, thermal, aging, and surface properties. The results highlight the promising anti-aging effects of lyophilisates, significantly enhancing the aging resistance of natural rubber. The aging factor was the closest to unity among all systems. Biomass and bio-ashes were also examined, offering insights into their influence on tensile strength, viscoelasticity, and surface wettability. The tensile strength values were almost 50% higher than those of the reference sample (8.5 MPa). The study provides a detailed understanding of the interactions between these bioadditives and natural rubber, showcasing their potential to enhance elastomer performance. These findings underscore the viability of Alfalfa-based bioadditives as sustainable options for improving rubber properties, with significant implications for industrial applications. Full article

An emerging drying method, far-infrared radiation heating-assisted pulsed vacuum drying (FIR-PVD), was employed to dry raspberries. In this study, the impacts of FIR-PVD, freeze drying (FD), and hot air drying (HAD) on drying characteristics and quality attributes, including color, rehydration ratio, content of total phenolics (TP), content of total monomeric anthocyanins (TMA), antioxidant activity, and microstructural attributes of dried raspberries, were examined. Results indicated that FIR-PVD notably shortened the drying time by 47.78% compared to HAD and by 73.89% compared to FD. The FIR-PVD samples exhibited the highest TP content, DPPH radical scavenging activity, and FRAP value, which were 17.73%, 6.09%, and 38.16% higher than those of the FD samples, respectively, and 2.78%, 2.77%, and 18.74% higher than those of the HAD samples. Significant correlations (p < 0.05) were observed between antioxidant capacity, as measured by DPPH and FRAP assays, and TP content. However, FD at a low temperature led to a higher TMA content than FIR-PVD and HAD. FIR-PVD resulted in the highest ΔE values of dried products due to the lightness enhancement. In addition, the dried products obtained by FIR-PVD had better rehydration capacity. These findings indicate that FIR-PVD presents a promising alternative method for drying raspberries, as it enhances drying efficiency and improves the quality attributes of the dried products. Full article

Apples are one of the most popular fruits in the world and have a significant share in domestic and international fruit production. Drying is a common method used to extend the shelf life of apples. However, it also induces irregular morphological changes in apples, which are essential to maintaining the structural integrity of the material. Therefore, it is necessary to understand the effect of cellular changes at the microscopic level on the macroscopic deformation of the material during drying. In this paper, the evolution of cell wall pectin fractions and viscoelastic properties of apples during freeze drying combined with hot air drying was investigated. The findings indicated that during the HAD stage, a decrease in the relaxation modulus (E₁) of the samples was observed in the compression tests when the sample temperature was significantly higher than the glass transition temperature (T_g). As the difference between the two decreased, the samples exhibited increased stiffness and higher E₁. The results of the pectin content analysis showed that the HAD process accelerated the loss and degradation of water-soluble pectin in the samples with high moisture content at the transition point. Simultaneously, the esterification degree of chelator-soluble pectin increased, leading to a reduction in the support provided to the cellular structure of the samples, which consequently affected their mechanical properties. These findings may provide valuable information for the application of freeze drying combined with hot air drying in the efficient processing of dried fruit and vegetable products. Full article

Sweet potato (Ipomoea batatas (L.) Lam.) is a nutrient-dense crop rich in fibre, minerals, and antioxidant compounds, including carotenoids and phenolic compounds, such as anthocyanins. Dehydrating sweet potato (SP) for flour production enhances its value and produces shelf-stable, health-promoting food products. This study investigated the effects of hot-air drying (HAD: 75 °C/20 h) and freeze-drying (FD: −41–30 °C/70 h) on the bioactive composition of flours from three SP varieties: Bonita (white-fleshed), Bellevue (orange-fleshed), and NP1648 (purple-fleshed). Key assessments included the total phenolic content (TPC), the total carotenoid content (TCC), and the total anthocyanin content (TAC) and the antioxidant activity (DPPH and FRAP). The results revealed distinct raw materials’ bioactive profiles: Bellevue was rich in TCC (49.3 mg of β-carotene/100 g db), NP1648 showed elevated TAC (27.3 mg of cyanidin-3-glucoside/100 g db), and Bonita exhibited minimal content of bioactive compounds. Both drying methods yielded significant losses of bioactive compounds, with the TPC decreasing by over 60%, while TAC and TCC losses did not exceed 32%, revealing higher stability. Multivariate analysis indicated that the variety significantly influenced the bioactive profiles more than the drying method. The interaction between carotenoids and anthocyanins and the SP fibrous composition likely contributed to their stability during drying, indicating that FD showed no advantages over HAD. The appealing colours and high antioxidant content of Bellevue and NP1648 flours suggest their potential as ingredients for enhancing foods’ bioactivity and sensory acceptance. Full article