CHARACTERIZATION OF IMMOBILIZED LIPASE IN ALUMINOSILICATE FOR LACTOSYL PALMITATE SYNTHESIS

Whey lactose can be esterified enzymatically by using immobilized lipase. The lipase can be isolated from Rhizopus oryzae, purified and immobilized in mesoporous aluminosilica. The use of immobilized lipase has advantages, there are longer shelf life and repeatable use. It is necessary to characterize the immobilized lipase dan ester product. The aim of the research was to characterize immobilized lipase, including determination lipase adsorption type in mesoporous aluminosilicate, immobilized lipase stability during storage time, efficiency of repetitive use of immobilized lipase. The result showed that lipase adsorption in mesoporous aluminosilicate was physical adsorption type through hydrogen bound and electrostatic interaction. Immobilized lipase stability was relatively constant at storage temperature 5 °C for 25 days resulting in 98.16% of initial activity. The repetitive use of immobilized lipase showed efficient until 5 uses within activity of 50.22%. The IR spectra of lactosyl palmitate from both whey and pure lactose result showed bands at wavelength number of 3462 cm-1(OH bond), 1739 cm-1 and 1747 (C=O ester bond) 1295 cm-1 dan 1242 cm-1 (C-O ester bond). In addition, the HLB value for lactosyl palmitate (whey) 4.708 and lactosyl palmitate (pure lactose) 4.715, therefore both lactosyl palmitate is appropriate as emulgator in W/O. Keywords: immobilized lipase, aluminosilica, lactose, whey, lactosyl palmitate

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Characterization of a Spray-Dried Soymilk Powder and Changes Observed During Storage

Food Science and Technology International ◽

10.1177/1082013209353236 ◽

2010 ◽

Vol 16 (2) ◽

pp. 169-178 ◽

Cited By ~ 11

Author(s):

G. Osthoff ◽

A. Hugo ◽

P. van Wyk ◽

M. de Wit ◽

S. Meyer

Keyword(s):

Unsaturated Fatty Acids ◽

Storage Temperature ◽

Chemical Properties ◽

Chemical Characterization ◽

Protein Composition ◽

Absorption Spectrometry ◽

Proximate Analysis ◽

Powder Particles ◽

High Level

Physical characterization of a soymilk powder was carried out by electron microscopy. Chemical characterization was analyzed by proximate analysis, mineral composition by atomic absorption spectrometry, fatty acid composition by gas chromatography and protein composition by electrophoresis. The powder consists of large granules of 60—80 μm, which may be hollow, with smaller granules of 10—20 μm attached to them. Powder particles are covered by a layer of fat. During storage at 25 °C fat is spreading over the surface, while at —12 °C the fat is contracting. This change affected chemical stability, resulting in high level of fat oxidation when stored at 4 °C or 25 °C as well as a decrease in unsaturated fatty acids. Storage also affected the chemical properties of the re-constituted soymilk; the pH of a 12% soy powder suspension increased from 6.68±0.05 to 7.06±0.08 after 12 months of storage. Storage temperature did not affect the pH of the suspension and this change could also not be ascribed to protein aggregation.

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Assessing the reaction conditions to mediate the milkfat-soybean oil enzymatic interesterification

BRAZILIAN JOURNAL OF FOOD TECHNOLOGY ◽

10.1590/1981-6723.11615 ◽

2016 ◽

Vol 19 (0) ◽

Cited By ~ 3

Author(s):

Ariela Veloso de Paula ◽

Gisele Fátima Morais Nunes ◽

Heizir Ferreira de Castro ◽

Júlio César dos Santos

Keyword(s):

Moisture Content ◽

Soybean Oil ◽

Rhizopus Oryzae ◽

Immobilized Lipase ◽

Fatty Acid Content ◽

Structured Lipids ◽

Nitrogen Atmosphere ◽

Reaction Conditions ◽

Oil Blend ◽

The Ideal

Summary A food grade lipase from Rhizopus oryzae immobilized on a hybrid polysiloxane-polyvinyl alcohol matrix (SiO2-PVA) was used as the biocatalyst to mediate the interesterification reactions of a blend containing 65% milkfat and 35% soybean oil. All the reactions occurred in an inert nitrogen atmosphere in cylindrical glass reactors (80 mL) with 40 g of the milkfat-soybean oil blend. The influence of the following variables was evaluated: biocatalyst loading (250-1500 activity units per gram of blend), biocatalyst moisture content (5-20%), temperature (45-60 °C) and incubation time (2-48 h). The reactions were monitored by determining the free fatty acid content, triacylglycerol (TAGs) composition in carbon species, and the consistency of the interesterified (IE) products. The reaction conditions were set based on the parameters that provided a high interesterification yield and good consistency of the final product within the ideal range (200 to 800 gf cm-2). Hence the best results were obtained using a biocatalyst loading of 500 U g-1 of blend with 10% moisture content at 45 °C for 4 h. Under these conditions the consistency of the interesterified product was 539.7 ± 38 gf cm-2. The results demonstrated the potential of the immobilized lipase to alter the TAGs profile of the milkfat-soybean oil blend, allowing for the production of structured lipids.

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CONSTRUCTION AND CHARACTERIZATION OF A NANOSTRUCTURED BIOCATALYST CONSISTING OF IMMOBILIZED LIPASE ON Mg-AMINO-CLAY

Clays and Clay Minerals ◽

10.1007/s42860-021-00130-z ◽

2021 ◽

Author(s):

Mingzhu Zhang ◽

Shiyong Sun ◽

Rui Lv ◽

Yevgeny Aleksandrovich Golubev ◽

Ke Wang ◽

...

Keyword(s):

Immobilized Lipase

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Characterization of the Spoilage Microbiota of Hake Fillets Packaged Under a Modified Atmosphere (MAP) Rich in CO2 (50% CO2/50% N2) and Stored at Different Temperatures

Foods ◽

10.3390/foods8100489 ◽

2019 ◽

Vol 8 (10) ◽

pp. 489 ◽

Cited By ~ 4

Author(s):

Adriana Antunes-Rohling ◽

Silvia Calero ◽

Nabil Halaihel ◽

Pedro Marquina ◽

Javier Raso ◽

...

Keyword(s):

Storage Temperature ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Modified Atmosphere ◽

Modified Atmospheres ◽

Different Temperatures ◽

Rrna Gene Sequencing ◽

Storage Temperatures

The aim of this study was to characterize the spoilage microbiota of hake fillets stored under modified atmospheres (MAP) (50% CO2/50% N2) at different temperatures using high-throughput 16S rRNA gene sequencing and to compare the results with those obtained using traditional microbiology techniques. The results obtained indicate that, as expected, higher storage temperatures lead to shorter shelf-lives (the time of sensory rejection by panelists). Thus, the shelf-life decreased from six days to two days for Batch A when the storage temperature increased from 1 to 7 °C, and from five to two days—when the same increase in storage temperature was compared—for Batch B. In all cases, the trimethylamine (TMA) levels measured at the time of sensory rejection of hake fillets exceeded the recommended threshold of 5 mg/100 g. Photobacterium and Psychrobacter were the most abundant genera at the time of spoilage in all but one of the samples analyzed: Thus, Photobacterium represented between 19% and 46%, and Psychrobacter between 27% and 38% of the total microbiota. They were followed by Moritella, Carnobacterium, Shewanella, and Vibrio, whose relative order varied depending on the sample/batch analyzed. These results highlight the relevance of Photobacterium as a spoiler of hake stored in atmospheres rich in CO2. Further research will be required to elucidate if other microorganisms, such as Psychrobacter, Moritella, or Carnobacterium, also contribute to spoilage of hake when stored under MAP.

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Preparation of Composite Monolith Supercapacitor Electrode Made from Textile-Grade Polyacrylonitrile Fibers and Phenolic Resin

Materials ◽

10.3390/ma13030655 ◽

2020 ◽

Vol 13 (3) ◽

pp. 655

Author(s):

Karim Nabil ◽

Nabil Abdelmonem ◽

Masanobu Nogami ◽

Ibrahim Ismail

Keyword(s):

Electrical Resistivity ◽

Surface Area ◽

Phenolic Resin ◽

Physical Adsorption ◽

Chemical Activation ◽

Specific Capacity ◽

Physical Activation ◽

Gravimetric Analysis ◽

Capacitive Properties

In this work a composite monolith was prepared from widely available and cost effective raw materials, textile-grade polyacrylonitrile (PAN) fibers and phenolic resin. Two activation procedures (physical and chemical) were used to increase the surface area of the produced carbon electrode. Characterization of the thermally stabilized fibers produced was made using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and Carbon-Hydrogen-Nitrogen(CHN) elemental analysis, in order to choose the optimum conditions of producing the stabilized fibers. Characterization of the produced composite monolith electrode was performed using physical adsorption of nitrogen at 77 °K, cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrical resistivity in order to evaluate its performance. All the electrodes prepared had a mixture of micropores and mesopores. Pressing the green monolith during the curing process was found to reduce largely the specific surface area and to some degree the electrical resistivity of the chemically activated composite electrode. Physical activation was more suitable than chemical activation, where it resulted in an electrode with specific capacity 29 F/g, good capacitive behavior and the stability of the electrical resistivity over the temperature range −130 to 80 °C. Chemical activation resulted in a very poor electrode with resistive rather than capacitive properties.

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