scholarly journals The effect of drying temperature on the properties of gelatin from carps (Cyprinus carpio) skin

2019 ◽  
Vol 37 (No. 4) ◽  
pp. 246-251 ◽  
Author(s):  
Joanna Tkaczewska ◽  
Maciej Wielgosz ◽  
Piotr Kulawik ◽  
Marzena Zajac

The influence of drying temperature on the characteristics and gel properties of gelatine from Cyprinus carpio L. skin was studied. Gelatine was extracted from the carp skin using NaOH and ethanol pre-treatment method, extracted in water in 45°C and then dried in 4 different temperatures: 50, 70, 80°C and freeze-dried. The  electrophoresis and functional properties of gelatines were investigated. Freeze drying allowed to obtain a high gelling force, and all other methods did not give satisfactory results. The proteins in gelatines dried at higher temperatures separated by electrophoresis gave severely blurred bands. It may be explained by thermal hydrolysis of collagen fibrils. Freeze drying is the only effective method for drying this product, which can be used in industry.

2012 ◽  
Vol 58 (4) ◽  
pp. 10-22 ◽  
Author(s):  
Martin Reli ◽  
Kamila Kočí ◽  
Vlastimil Matějka ◽  
Pavel Kovář ◽  
Lucie Obalová

Abstract The kaolinite/TiO2 composite (60 wt% of TiO2) was prepared by thermal hydrolysis of a raw kaolin suspension in titanyl sulphate and calcined at different temperatures (600, 650 and 700°C) and for different times (1, 2 and 3 h). The obtained samples were characterized by XRPD, N2 physical adsorption and SEM, and tested for photocatalytic reduction of CO2. The different calcination conditions did not influence TiO2 phase composition, only slightly changed the specific surface area, and significantly affected crystallite size of kaolinite/TiO2 composite. A higher temperature and longer duration of calcination lead to higher crystallinity of the powder. The photocatalytic results showed that the crystallite size determined the efficiency of kaolinite/TiO2 photocatalysts.


2021 ◽  
Author(s):  
Soo Takasu ◽  
Isabella Supardi Parida ◽  
Yoshihiro Kojima ◽  
Toshiyuki Kimura ◽  
Kiyotaka Nakagawa

We demonstrated the conversion of GAL-DNJ into DNJ improves mulberry leaves bioavailability and constructed a novel enzymatic-based method to induce the hydrolysis of GAL-DNJ to DNJ.


2007 ◽  
Vol 19 (1) ◽  
pp. 303
Author(s):  
M. Nakai ◽  
N. Kashiwazaki ◽  
N. Maedomari ◽  
M. Ozawa ◽  
J. Noguchi ◽  
...  

During fertilization, sperm penetration (gamete membrane fusion and exposure of sperm cytoplasm) allows oocyte activation (resumption of oocyte meiosis, pronuclear formation, etc.) by inducing an elevation of the intracellular free Ca2+ concentration. So a spermatozoon ought to be able to fully activate an oocyte. However, in pig ICSI oocytes, although a spermatozoon is injected successfully into ooplasm, complete activation is deficient in some of the oocytes. A variety of sperm pre-treatments before ICSI have been reported; however, there is a possibility that the treatment affects the ability to activate oocytes after the injection. We examined the effect of sperm treatments (freezing, freeze-drying, and sonication) on the ability to activate oocytes. Ejaculated boar semen was centrifuged (10 min, 600g) and the supernatant was discarded. The sperm pellet was resuspended in Modena solution (Weitze 1991 Reprod. Domest. Anim. (Suppl. 1), 231–253). The sperm were then treated with or without sonication for 10 s (fresh whole and sonicated sperm, respectively). The freezing of sperm was carried out as was described (Kikuchi et al. 1998 Theriogenology 50, 615–623). Frozen–thawed spermatozoa were then treated with or without sonication (frozen–thawed sonicated and whole sperm, respectively). The fresh whole and sonicated sperm were subjected to a freeze-drying system and the sperm were then re-hydrated (freeze-dried whole and sonicated sperm, respectively). A whole sperm or 1 or 3 sonicated sperm heads were then injected into in vitro-matured oocytes, as described previously (Nakai et al. 2003 Biol. Reprod. 68, 1003–1008; 2006 Reproduction 131, 603–611). Sham injection was also performed. No artificial stimulation was added to the injected oocytes. The oocytes with more than one pronucleus(i) at 10 h after the injection were defined as being activated. As shown in Table 1, the rates of activated oocytes after injection of one sonicated head or sham injection were significantly lower than those of the oocytes injected with whole sperm or 3 sonicated sperm heads in each sperm source (P < 0.05 by ANOVA and Duncan's multiple range test). Furthermore, the rates of activated oocytes for each injection category were not different among the 3 sperm sources. These results suggest that sonication before ICSI may reduce the quantity of activation-inducing sperm factor. It is also suggested that sperm pre-treatment such as freezing or freeze-drying does not affect the ability for oocyte activation. Table 1. Effect of sperm treatment on oocyte activation after ICSI


1970 ◽  
Vol 68 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Masatoshi Suzuki

SummaryUnpurified and purified smallpox vaccines were prepared from calf dermal pulp, or chorioallantoic membrane (CAM) of hen eggs infected with vaccinia virus, and freeze-dried. The protective effect of various suspending media was investigated both in the course of the freeze-drying and in the period of subsequent storage of the dried product at different temperatures, including 100° C.Single media consisting of either sodium glutamate or peptone were effective in the preservation of both unpurified and purified vaccines prepared from calf dermal pulp or CAM. It was shown that there was an optimal concentration of sodium glutamate for the preservation of the vaccine preparations, especially of the purified vaccine.Combined media, consisting of soluble starch, polyvinylpyrrolidone or sodium carboxymethyl cellulose with sodium glutamate, were effective with the purified vaccine when the concentration of sodium glutamate exceeded the optimum necessary for preservation.


2006 ◽  
Vol 52 ◽  
pp. 17-24
Author(s):  
Lela Acevska ◽  
Kristina Mladenovska ◽  
Tanja Petreska Ivanovska ◽  
Maja Jurhar Pavlova ◽  
Milena Petrovska ◽  
...  

Viability of L. casei during fermentation in soymilk and freeze-dried soymilk; effect of cryoprotectant, rehydration and storage temperature The aim of the work was to investigate the behaviour of L. casei and the effect of sorbitol on its viability during fermentation in soymilk drink. Values for pH, ranging from 6.82 to 3.42 in the soymilk drink without sorbitol and from 6.74 to 3.41 in the drink with sorbitol were noted during 72 h of fermentation at 25oC. The corresponding values for titratable acidity ranged from 0.071% to 0.758% and from 0.073% to 0.761%, respectively. Soymilk was found to support the growth of L. casei with improvement in viability for 0.24 log at the end of fermentation when sorbitol was added. Survival of L. casei and the effectiveness of sorbitol in improving viability during freeze-drying, subsequent rehydration and during a 5-week period of storage under different temperatures were also investigated. After freeze-drying, L. casei exhibited a survival percent of approximately 46%. Sorbitol improved the viability of L. casei by 0.51 log immediately after freeze-drying and by 1.30 log and 0.47 log during five weeks of storage at 25oC and 4oC, respectively. Further study revealed that the freeze-dried fermented soymilk rehydrated at 45oC was optimum for the recovery of L. casei with improvement in recovery for 0.68 log when sorbitol was added. A higher percent of survival was noted when the dried soymilk was stored at 4oC than at 25oC with improved viability at the end of 5 weeks storage for approximately 6 log for drinks with and without sorbitol. Fermented dried soymilk with sorbitol afforded significant tolerance of L. casei to acid stress. Generally, a stable probiotic diary product was prepared in which the concentration of L. casei remained above therapeutic level of 107 cfu/ml.


Author(s):  
Atoke Olaide Ogunbayo ◽  
Olawole Ogirima Olanipekun ◽  
Damilola Elizabeth Babatunde

Pharmaceutics ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 433 ◽  
Author(s):  
Tarun Ojha ◽  
Vertika Pathak ◽  
Natascha Drude ◽  
Marek Weiler ◽  
Dirk Rommel ◽  
...  

Poly(n-butyl cyanoacrylate) microbubbles (PBCA-MB) are extensively employed for functional and molecular ultrasound (US) imaging, as well as for US-mediated drug delivery. To facilitate the use of PBCA-MB as a commercial platform for biomedical applications, it is important to systematically study and improve their stability and shelf-life. In this context, lyophilization (freeze drying) is widely used to increase shelf-life and promote product development. Here, we set out to analyze the stability of standard and rhodamine-B loaded PBCA-MB at three different temperatures (4 °C, 25 °C, and 37 °C), for a period of time of up to 20 weeks. In addition, using sucrose, glucose, polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG) as cryoprotectants, we investigated if PBCA-MB can be lyophilized without affecting their size, concentration, US signal generation properties, and dye retention. Stability assessment showed that PBCA-MB remain largely intact for three and four weeks at 4 °C and 25 °C, respectively, while they disintegrate within one to two weeks at 37 °C, thereby compromising their acoustic properties. Lyophilization analyses demonstrated that PBCA-MB can be efficiently freeze-dried with 5% sucrose and 5% PVP, without changing their size, concentration, and US signal generation properties. Experiments involving rhodamine-B loaded MB indicated that significant dye leakage from the polymeric shell takes place within two to four weeks in case of non-lyophilized PBCA-MB. Lyophilization of rhodamine-loaded PBCA-MB with sucrose and PVP showed that the presence of the dye does not affect the efficiency of freeze-drying, and that the dye is efficiently retained upon MB lyophilization. These findings contribute to the development of PBCA-MB as pharmaceutical products for preclinical and clinical applications.


1992 ◽  
Vol 25 (4-5) ◽  
pp. 211-218 ◽  
Author(s):  
G. Smith ◽  
J. Göransson

Chemical pre-treatment with highly charged metal salts gives an effluent low in both organic substances and phosphorus. To use pre-precipitation as the first step in sewage treatment improves nitrification in the following biological step. The chemically precipitated sludge contains 75% or more of the organic substances in the raw sewage and can by a hydrolysis process be converted to readily degradable organic substances. This paper will review experiences from tests with thermal hydrolysis in a full scale plant as well as results from laboratory studies.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 853
Author(s):  
Begüm Önal ◽  
Giuseppina Adiletta ◽  
Marisa Di Matteo ◽  
Paola Russo ◽  
Inês N. Ramos ◽  
...  

The objective of this research was to evaluate the effect of drying temperature and innovative pre-treatments (i.e., microwave and ultrasound) on “Rocha” pear drying behavior and quality characteristics, such as color, total phenolic content and antioxidant activity. Experiments were carried out with pear slabs subjected to microwaves (2450 MHz, 539 W, 4 min, microwave oven) and ultrasounds (35 kHz, 10 min, in an ultrasonic bath) as well as control samples. The drying process was conducted in a tray dryer at three different temperatures (50, 55 and 60 °C) and a fixed air velocity of 0.75 m/s. Microwave technology resulted in a higher quality deterioration in dried pear samples compared to those of controls and ultrasound pre-treated samples. The combined application of ultrasound pre-treatment and the higher drying temperature of 60 °C was characterized by the lowest color changes (ΔE = 3.86 ± 0.23) and higher preservation of nutritional parameters (total phenolic content, TPC = 345.60 ± 8.99; and antioxidant activity, EC50 = 8.80 ± 0.34). The drying characteristics of pear fruits were also analyzed by taking into account empirical models, with the Page model presenting the best prediction of the drying behavior. In conclusion, ultrasound application is a promising technology to obtain healthy/nutritious dried “Rocha” pear snacks as dietary sources for consumers.


HortScience ◽  
2021 ◽  
Vol 56 (2) ◽  
pp. 242-243
Author(s):  
Grady H. Zuiderveen ◽  
Eric P. Burkhart ◽  
Joshua D. Lambert

Goldenseal (Hydrastis canadensis L.) is a medicinal forest herb native to Appalachia. Its roots and rhizomes are used as an antimicrobial and for the treatment of intestinal ailments. Three alkaloids–berberine, hydrastine, and canadine–are recognized as the major bioactive constituents in goldenseal. One important postharvest processing step for goldenseal is drying; however, it is not known how drying temperature influences the concentrations of these alkaloids. In this study, pre-emergent (dormant) goldenseal samples were freeze-dried or air-dried at six different temperatures (26.7 to 54.4 °C) to determine the relationship between drying temperature and alkaloid content in the rhizome and roots. High performance liquid chromatography analysis showed that berberine and hydrastine levels were unaffected by drying temperature, while canadine levels decreased as temperature increased (0.55% w/w on average when samples were freeze-dried, down to 0.27% w/w on average when dried at 54.4 °C). While canadine is the least abundant alkaloid of the three, it is known to have key antibacterial properties. Developing a more standardized drying protocol for goldenseal could lead to a more predictable phytochemical profile.


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