Effects Of Different Drying Processes Research Articles

Effects of Different Drying Processes on the Bioactivity and Rutin Content of Prunus spp. (Plums).

The aim of this study was to investigate the effects of drying process preparations, solvent type, and different species of Prunus spp. (European, Japanese, and cherry plums) on bioactive properties (antioxidant, anti-lipid peroxidation, anti-tyrosinase, and anti-inflammatory activities) and rutin content. Leaves and fresh fruits of plums were dried using a cold process (vacuum freeze dryer at -105 ± 5°C) and a hot process (hot air oven at 50 ± 0.5°C). The dried plant material was then extracted using ethanol and propylene glycol to obtain ethanolic crude extracts and propylene glycol extract solutions. These extracts were then tested for phenolic and flavonoid contents and their potential biological activities and analyzed for rutin content using the HPLC method. The results showed that the ethanolic extract of plum leaves obtained via the cold-drying process exhibited higher total phenolic and flavonoid contents (96.94 ± 6.73-112.34 ± 9.08 mg GAE/g sample and 105.10 ± 11.31-185.94 ± 23.35 mg QE/g sample, respectively), as well as greater potential for antioxidant activity (DPPH with IC50 = 29.97 ± 1.17 to 31.44 ± 4.16 μg/mL), anti-tyrosinase activity (40.34 ± 1.27%-46.91 ± 0.22%), and anti-lipid peroxidation activity (34.10 ± 4.88%-38.27 ± 2.12%). They also exhibited higher anti-inflammatory activity by inhibiting NO (20.16 ± 0.12%-40.05 ± 0.42%), IL-6 (37.81 ± 3.01%-42.37 ± 8.92%), and TNF-α (45.96 ± 7.93%-63.28 ± 6.44%) compared to fresh plum fruit extracts and other extraction procedures. These activities correlated with the rutin content, which was high in the plum leaf extracts (28.52 ± 0.00%-43.82 ± 0.13% w/w). European plums tended to exhibit greater bioactivities and higher rutin content compared to other species. These findings indicate that plum leaf extracts are a promising source for further applications in food, nutrition, and health products.

Effect of Different Drying Processes on Antioxidant and Antidiabetic Properties of Pomegranate Press Wastes

Today, with the understanding of the favourable effects of fruit consumption on health, the consumption of pomegranate has increased gradually, and solution methods were sought to evaluate the peel and seed parts that emerge after the fruit is sorted. In this study, the effects of different drying processes (microwave, drying oven, and freeze-drying) and different extraction solvents (ethanol and methanol) on the antioxidant and antidiabetic activities of pomegranate press wastes were investigated. While the highest total phenolic content (TPC) was in freeze-dried methanolic extracts (5758.70 mg GAE 100 g-1), the highest total flavonoid content (TFC) and total monomeric anthocyanin (MA) contents were determined in microwave-dried ethanolic extracts with values of 1068.75 mg QE 100 g-1 dw and 215.44 mg cyn-3-glu 100 g-1, respectively. All samples had higher α-glucosidase inhibitory activity compared to acarbose. The results showed that pomegranate press waste, which is thought to have no use in the food industry, is a potential resource that can be used in the pharmacology and cosmetics industries as well as its use as a food supplement; thanks to its high antioxidant and antidiabetic properties.

Effect of Different Drying Processes on the Physicochemical and Antioxidant Properties of Thinned Young Apple

Abstract In China, there are about 1.6 million tons of thinned young apples (TYAs) every year after blossoming and fruit thinning. These resulting fruits, in reality, could be utilized as agricultural and food resource. This study was undertaken to evaluate the influence on physical properties, bioactive attributes of TYAs that were subjected to chosen drying techniques. In general, significant differences (p < 0.05) exist in physical appearance and polyphenol. Antioxidant capacity was also investigated on the basis of assay for Trolox equivalent antioxidant capacity (TEAC) by 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), reducing power and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability. Judging from the results, it was concluded that hot air drying at 60℃ is appropriate for large-scale production; furthermore, vacuum freeze drying tends to manufacture high-value up-market TYA products that are available to give the best results for dehydrated fruits. It is suggested that TYA has great potential in the food industry as functional ingredient.

Effect of Different Drying Processes on the Protein Degradation and Sensory Quality of Layú: A Chinese Dry-Curing Grass Carp

Five different drying methods, sun drying, intermittent drying, low-temperature drying at 5°C, low-temperature drying at 15°C, and hot-air drying at 45°C, were comparatively evaluated based on physicochemical properties and sensory properties of dry-cured Layú. Sun drying and intermittent drying Layú showed superior sensory qualities compared with other dried samples. Based on the comprehensive comparison of sensory qualities and safety concerns, intermittent drying Layú was more acceptable compared to other dry-cured Layú and thus was recommended for dry-curing fish products as it could shorten the drying time with relative constant drying rate, increased flavor amino acid content, and fewer safety concerns.

Effects of Different Drying Processes on the Material Properties of Bacterial Cellulose Membranes

AbstractSummary: Membranes of bacterial cellulose produced by Gluconacetobacter xylinus show a high water and gas permeability that can be altered by different drying techniques. It could be shown that freeze‐drying reduces the swellability of the polymer membranes by a factor of 5 while evaporation drying causes a reduction by a factor of 50. The strong decrease of swellability for an evaporation dried membrane could be correlated with a reduction of the absolute number of polymer strands that form the network structure of the membrane, determined with oscillatory shear rheological experiments. The removal of network meshes by a complete aggregation of polymer strands could be confirmed by IR‐spectroscopy with an increased degree of intramolecular hydrogen bonding of cellulose strands. In contrast to this, the freeze‐drying process shows a slight increase of the number of network meshes due to partial aggregation of free polymer strands. Freeze‐dried membranes show a gas permeability two orders of magnitude higher then evaporation dried membranes. The absolute permeability strongly depends on the bacterial strain used for the polymer membrane synthesis and varies by up to 1.5 orders of magnitude for the same drying process. The Young's modulus of the polymer membranes varies with the bacterial strain used, but does not show the same trends as the permeability. Finally, a comparison of the characterized properties shows that only one of the tested strains shows the capability to synthesize membranes that meets the requirements for an application as a wet wound dressing.

Effects of Different Drying Processes on Oil Absorption and Microstructure of Tortilla Chips

ABSTRACTTortilla chips were slow dried after baking and then fried in fresh soybean oil. Control chips were not dried before frying. Final oil content of sun‐dried tortilla chips was significantly (P < 0.05) lower than those receiving the control treatment. As a result of drying, the structure of the tortilla chips was tighter before frying but expanded significantly during frying. An attempt was made to produce tortilla chips with the same characteristics of the sun‐dried chips using impinging hot‐air drying techniques. Results indicated that tortilla chips drying rate was mostly affected by air temperature; texture was crispier at higher air temperatures; shrinkage of the piece was higher at lower convective heat transfer coefficient; and microstructure looked smoother at higher air temperature.