Influence of drying method and ageing on chemical and physical properties andin vitrodegradation characteristics of grass and maize samples

1996 ◽  
Vol 126 (1) ◽  
pp. 7-14 ◽  
Author(s):  
J. W. Cone ◽  
A. H. Van Gelder ◽  
H. J. P. Marvin

SUMMARYThe influence of different drying conditions on the chemical composition, physical properties,in vitroorganic matter degradability and fermentation kinetics of forages was investigated using young and old grass (Lolium perenne) samples (harvested on 15 June and 9 July 1992 at Lelystad, The Netherlands) and young and old maize (Zea mayscv. Scana) stem samples (harvested on 19 August and 30 September 1991 at Lelystad). The samples were either freeze-dried with a maximum sample temperature of 10 °C, dried in a vacuum at 20 °C or air-dried at 30, 50, 70 and 105 °C. The different drying methods had little effect on ash, acid detergent fibre (ADF), acid detergent lignin (ADL), crude fibre and crude protein (CP) contents andin vitrodegradation of the forage samples. However, some effects were found for sugars and phenolic acids. The neutral detergent fibre (NDF) content in protein-rich samples and the fermentation kinetics in rumen fluid differed significantly according to drying method. In samples dried other than by freeze-drying, proteins were bound to the NDF content and in some cases an effect on the amount of soluble sugars was also seen. Physical properties of the samples were determined by differential scanning calorimetry (DSC) and differences were found between freeze-dried materials and those dried at 70 °C. The influence of age on the maize samples was very pronounced, whereas it had little effect on the characteristics of the grass samples, with the exception of a decreased CP content and an increased sugar content after acid hydrolysis.

2013 ◽  
Vol 27 (2) ◽  
pp. 143-149 ◽  
Author(s):  
E. Janiszewska ◽  
D. Witrowa-Rajchert ◽  
M. Kidoń ◽  
J. Czapski

Abstract The aim of the study was to determine the effect of different drying methods on selected physical properties of pomace obtained from purple carrot cv. Deep Purple. Drying was performed using four methods: convective, microwave-convective, infrared-convective and freeze-drying. The freeze-dried material had the lowest apparent density (422 kg m-3), which was caused by slight shrinkage, and indicated high porosity. Apparent density was almost three times greater in dried materials produced using the other drying methods as compared to the freeze-dried variants. Freeze-dried pomace adsorbed vapour more quickly than the other dried variants, which was caused by its high porosity and relatively low degree of structural damage. Rehydration characteristicswere significantly affected by the dryingmethod. The highest mass increase and losses of soluble substance were recorded for the freeze-dried samples. Conversely, the traditional convective drying method resulted in the lowest mass increase and soluble substance leaching. A positive linear correlation was found between the loss of soluble dry substance components and the absorbance of liquid obtained during rehydration.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2644
Author(s):  
Jan Oszmiański ◽  
Sabina Lachowicz ◽  
Paulina Nowicka ◽  
Paweł Rubiński ◽  
Tomasz Cebulak

The present study aimed to evaluate the effect of Jerusalem artichoke processing methods and drying methods (freeze drying, sublimation drying, vacuum drying) on the basic physicochemical parameters, profiles and contents of sugars and polyphenolic compounds, and health-promoting properties (antioxidant activity, inhibition of the activities of α-amylase, α-glucosidase, and pancreatic lipase) of the produced purée. A total of 25 polyphenolic compounds belonging to hydroxycinnamic phenolic acids (LC-PDA-MS-QTof) were detected in Jerusalem artichoke purée. Their average content in the raw material was at 820 mg/100 g dm (UPLC-PDA-FL) and was 2.7 times higher than in the cooked material. The chemical composition and the health-promoting value of the purées were affected by the drying method, with the most beneficial values of the evaluated parameters obtained upon freeze drying. Vacuum drying could offer an alternative to freeze drying, as both methods ensured relatively comparable values of the assessed parameters.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4153
Author(s):  
Doaa Abouelenein ◽  
Ahmed M. Mustafa ◽  
Simone Angeloni ◽  
Germana Borsetta ◽  
Sauro Vittori ◽  
...  

Strawberry is the most consumed berry fruit worldwide due to its unique aroma and flavor. Drying fruits to produce a powder represents one of the possible conservation methods to extend their shelf-life. The aim of the present study was to compare the influence of freezing and different drying methods on the volatile profile of strawberry using the HS-SPME/GC–MS method, in addition to analysis of strawberry jam volatiles. A total of 165 compounds were identified, accounting for 85.03–96.88% of the total volatile compositions. Results and PCA showed that freezing and each drying process affected the volatile profile in a different way, and the most remarkable representative differential volatiles were ethyl hexanoate, hexyl acetate, (E)-2-hexenyl acetate, mesifurane, (E)-nerolidol, γ-decalactone, 1-hexanol, and acetoin. Shade air-dried, frozen, freeze-dried, and oven-dried 45 °C samples retained more of the fruity and sweet aromas of strawberry, representing more than 68% of the total aroma intensity according to the literature. In contrast, the microwave-drying method showed drastic loss of fruity esters. Strawberry jams demonstrated complete destruction of esters and alcohols in most jams, while terpenes were significantly increased. These findings help better understand the aroma of strawberry and provide a guide for the effects of drying, freezing, and jam processing.


2019 ◽  
Vol 33 (8) ◽  
pp. 1128-1144 ◽  
Author(s):  
Vahideh Raeisdasteh Hokmabad ◽  
Soodabeh Davaran ◽  
Marziyeh Aghazadeh ◽  
Reza Rahbarghazi ◽  
Roya Salehi ◽  
...  

The major challenge of tissue regeneration is to develop three dimensional scaffolds with suitable properties which would mimic the natural extracellular matrix to induce the adhesion, proliferation, and differentiation of cells. Several materials have been used for the preparation of the scaffolds for bone regeneration. In this study, novel ethyl cellulose-grafted-poly (ɛ-caprolactone) (EC-g-PCL)/alginate scaffolds with different contents of nano-hydroxyapatite were prepared by combining electrospinning and freeze-drying methods in order to provide nanofibrous/macroporous structures with good mechanical properties. For this aim, EC-g-PCL nanofibers were obtained with electrospinning, embedded layer-by-layer in alginate solutions containing nano-hydroxyapatite particles, and finally, these constructions were freeze-dried. The scaffolds possess highly porous structures with interconnected pore network. The swelling, porosity, and degradation characteristics of the EC-g-PCL/alginate scaffolds were decreased with the increase in nano-hydroxyapatite contents, whereas increases in the in-vitro biomineralization and mechanical strength were observed as the nano-hydroxyapatite content was increased. The cell response to EC-g-PCL/alginate scaffolds with/or without nano-hydroxyapatite was investigated using human dental pulp stem cells (hDPSCs). hDPSCs displayed a high adhesion, proliferation, and differentiation on nano-hydroxyapatite-incorporated EC-g-PCL/alginate scaffolds compared to pristine EC-g-PCL/alginate scaffold. Overall, these results suggested that the EC-g-PCL/alginate-HA scaffolds might have potential applications in bone tissue engineering.


2018 ◽  
Vol 46 (2) ◽  
pp. 449-456 ◽  
Author(s):  
Hacer COKLAR ◽  
Mehmet AKBULUT ◽  
Semih KILINC ◽  
Ali YILDIRIM ◽  
Iliasu ALHASSAN

Flowers, leaves and fruits of hawthorn plant are traditionally used for treating diseases like hypertension and atherosclerosis. The medicinal effects of the plant are generally attributed to its phenolic compounds. However, the fruits are perishable materials because of their high content of water, and generally dried and stored to be used outside its season. The main aim of this research was to investigate the effect of different drying methods on phenolic compounds of the hawthorn fruit. Fruits were collected from the wild growing trees in Turkey. De-seeded fruits were dried in freeze-, oven- (60 oC) and microwave pretreated oven drying (microwave application for 5 min at 360 W before drying at 60 oC) methods and analyzed for antioxidant activity, phenolic compounds, total phenolic content and color parameters. Total phenolic content of fresh hawthorn fruits was found as 13.36 mg g-1 DW. Oven- and microwave pretreated oven drying methods had a reductive effect on total phenolic content and antioxidant activity of fruits when compared to freeze drying method. (-)-Epicatechin (994.10 mg kg-1 DW), rutin (765.30 mg kg-1 DW), and procyanidin B2 (553.80 mg kg-1 DW) were the main phenolics of the fruit. Lowest values of these three compounds were observed in oven-dried fruits. Microwave pretreatment oven drying method resulted in browner product. Although the highest phenolic concentration and antioxidant activity were occurred in freeze-dried sample, microwave pretreatment before oven drying could be applied to reduce the time and cost of drying in terms of phenolic compounds and antioxidant activity.


1995 ◽  
Vol 1995 ◽  
pp. 110-110 ◽  
Author(s):  
S Akhter ◽  
E Owen ◽  
M K Theodorou ◽  
S L Tembo ◽  
E R Deaville

Previous studies (El Shaer, Omed and Axford, 1987; Akhter, Owen, Fall, O'Donovan and Theodorou, 1994) with the two-stage in vitro procedure of Tilley and Terry (1963) have shown a high correlation between digestibilities of forages as determined using either sheep rumen liquor, sheep faeces or cow faeces as the microbial inoculum. In the first study of the of the present investigation one objective was to examine the repeatability of these digestibility measurements when made on different occasions. A second objective was to assess whether the correlations between faecal and rumen fluid based inocula could be improved if microorganisms were obtained from pairs rather than individual animals. The objective in the second study using forages of known in vivo digestibility, was to investigate the effect of freezing or freeze-drying of faeces on the repeatability of digestibilities of forages determined in vitro using micro-organisms from cow faeces.


Author(s):  
Vinita Vinita ◽  
Darshan Punia

The present investigation was conducted to evaluate the nutrient composition of four varieties of date fruit. The results of the study indicated that the variety Shamran had highest protein (2.77%) content and the variety Medjool the lowest (1.88%). Fat and crude fibre contents of date fruit varieties ranged from 0.17 to 0.50% and 1.71 to 2.22%, respectively. The variety Medjool had lowest amount of total soluble sugars (67.49g/100g) and reducing sugar (61.31g/100g). All the varieties of date fruit differed non-significantly among themselves for their non- reducing sugar content. The variety Khadrawi had the highest amount of starch content. Total dietary fiber (11.70g/100g) and soluble dietary fiber (3.34g/100g) were highest in variety Hillawi. All the four varieties of date fruit differed significantly from each other for their total dietary fiber content and soluble dietary fiber content. The varieties Khadrawi (8.46%), Hillawi (8.35%) and Shamran (7.94%) had significantly (p£ 0.05) higher insoluble dietary fiber as compared to variety Medjool (4.25%). The variety Shamran had highest amount of calcium (195.33mg/100g) and zinc (1.81mg/100g). The variety Medjool contained lowest amount of calcium (70.33mg/100g), iron (1.91mg/100g) and potassium (713mg/100g) while the highest amount of phosphorus (52.66mg/100g). A non-significant (p£0.05) difference was observed in magnesium content of all the varieties. Polyphenol content of date fruits from different varieties ranged from 228.79 to 253.21 mg/100g.


Author(s):  
Brilliant Margalin ◽  
S. P. Edijanto ◽  
Paulus B. Notopuro

Fibrin glue is a useful biological product to stop bleeding, adhesive tissue and accelerate wound healing. Preparation of Fibrin Glue requires fibrinogen and thrombin components. The routine cryoprecipitation method performed at the Blood Bank can be used to improve the quality of the fibrinogen component. The Freeze Drying process can increase the retention time of plasma products at room temperature. Yield Fibrinogen and Tensile Strength is a quantitative and qualitative parameter of preparation quality of fibrin glue. This study focused on finding differences between Tensile Strength and Yield Fibrinogen on fibrin glue preparative by cryoprecipitate with and without freeze drying methods.This study is in vitro laboratory experiments design by comparing the Yield Fibrinogen and Tensile Strength of fibrin glue preparation from cryoprecipitic plasma with and without freeze dried process. The results were analyzed comparatively using paired T test.The plasma fibrinogen content of the sample was 237.66 ± 67.10 mg / dL. The fibrinogen content of the cryoprecipitate component without freeze drying process was 327.74 ± 103.42 mg / dL with a yield fibrinogen of 1.38 ± 0.25. The fibrinogen content of the cryoprecipitate component with freeze drying process was 251.20 ± 103.91 mg / dL with yield fibrinogen 1.04 ± 0.25. Tensile strength of fibrin glue from cryoprecipitate without freeze drying process was found to average 0.52 ± 0.18. Tensile strength of fibrin glue from cryoprecipitate with freeze drying process was found to average 0.33 ± 0.12. There was a significant difference between yield fibrinogen and tensile strength of fibrin glue preparation of cryoprecipitation method with and without freeze dried process.There is a significant difference on yields fibrinogen and tensile strength in the preparation of fibrin glue by the freeze drying process which is probably due to changes in the structure and function of fibrinogen proteins.


2019 ◽  
Vol 70 (2) ◽  
pp. 491-494
Author(s):  
Lacramioara Oprica ◽  
Radu Gheorghe Antohe ◽  
Andreea Verdes ◽  
Marius Nicusor Grigore

The aims of this work was to investigate the effect of thermal drying method (vacuum oven drying), and nonthermal drying method (freeze drying) on the flavonoids content in two red grape varieties (Cabernet Sauvignon and Merlot) from different grape components (seed, skin, and pulp) collected from two experimental fields, Bucium and Copou (North East of Romania). In general, the fresh skin of Cabernet and Merlot varieties has the highest flavonoids content followed by those obtained by oven-drying and freeze-drying process. A similar situation was observed in the other component of grape varieties like pulp and seeds meaning in the way that the flavonoid content in oven-dried samples were higher than that in the freeze-dried samples. In addition, from both varieties, Merlot collected from Bucium presented the highest content compared with Cabernet.


Sign in / Sign up

Export Citation Format

Share Document