Encapsulation of krill oil by spray drying

[EN] An oil from Pacific krill (Euphausia pacifica) has a high content of PUFAs and phospholipids. The sediment was formed with homogenization of krill oil and maltodextrin (MD; dextrose equivalent (DE) = 19) solution using sodium caseinate, gum arabic, hydrolyzed whey protein or modified starch as a surfactant. Quillaja saponin could form the emulsion without the sediment. MD (28.5 wt%) was solubilized with distiller water (50 wt%) and mixed with krill oil (20wt%) and Quillaja saponin (1.5 wt%). The homogenized solution was spray-dried using Okawara-L8 spray dryer with a centrifugal atomizer. Spray-dried powder was evaluated in the oil-droplet size and surface-oil content.This research was supported by grants from the Project of the NARO Bio-oriented Technology Research Advancement Institution (the special scheme project on vitalizing management entities of agriculture, forestry and fisheries).Takashige, S.; Hermawan Dwi, A.; Sultana, A.; Shiga, H.; Adachi, S.; Yoshii, H. (2018). Encapsulation of krill oil by spray drying. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 587-594. https://doi.org/10.4995/IDS2018.2018.7323OCS58759

Subcritical Water Treatment for Producing Seasoning From Semidried Isada Krill

Semidried Isada krill (Euphausia pacifica) was treated with boiling water and subcritical water at 100–240C for 10 min with a semidried krill to a water ratio of 8/52 w/v to produce seasoning. The protein concentration, lipid content and odor concentration of the extract increased after increasing the treatment temperature. The highest protein content of the extract (0.047–0.049 kg/kg-extract) was obtained by subcritical water treatment at 180 or 200C. Compounds with lower molecular mass were detected in the extracts derived from subcritical water treatment at temperatures higher than 160C. The extract prepared by subcritical water treatment at 160 and 180C received the high score in the flavor preference test by a group of panelists. Treatment at temperatures lower and higher than 160–180C, respectively, conferred undesirable fishy and smoky or burnt odors to the extracts and residues

Compositions, flavour and antiradical properties of products from subcritical water treatment of raw Isada krill

Comparative analysis of subcritical water (SCW) treatment and ambient pressure boiling one of raw Isada krill was performed for the nutritive, flavour and antiradical properties of krill extracts and residues as well as the molecular mass and odour intensity of the extract. SCW treatment was performed for 10 min in a batch-type vessel in the temperature range of 100–240 °C, using a 1:1 weight ratio of raw krill to water. Higher protein and lipid contents were obtained by SCW treatment relative to boiling. The lipid content of the SCW extracts increased with increasing treatment temperature. Protein was the main component in these extracts, and the highest protein content was achieved by SCW treatment at 200 °C. High-molecular-mass species decomposed under SCW treatment at high temperatures with consequent generation of smaller molecules. The antiradical activity of the SCW extract, determined by DPPH and ABTS assays, increased with increasing treatment temperature. The krill extracts and residues exhibited shrimp-like flavour, and the most desirable flavour was obtained by SCW treatment at 140 °C or 160 °C for 10 min. The treatment would be applicable for the production of seasonings from Isada krill

Ring-originated anisotropy of local structural ordering in amorphous and crystalline silicon dioxide

Abstract Rings comprising chemically bonded atoms are essential topological motifs for the structural ordering of network-forming materials. Quantification of such larger motifs beyond short-range pair correlation is essential for understanding the linkages between the orderings and macroscopic behaviors. Here, we propose two quantitative analysis methods based on rings. The first method quantifies rings by two geometric indicators: roundness and roughness. These indicators reveal the linkages between highly symmetric rings and crystal symmetry in silica and that the structure of amorphous silica mainly consists of distorted rings. The second method quantifies a spatial correlation function that describes three-dimensional atomic densities around rings. A comparative analysis among the functions for different degrees of ring symmetries reveals that symmetric rings contribute to the local structural order in amorphous silica. Another analysis of amorphous models with different orderings reveals anisotropy of the local structural ordering around rings; this contributes to building the intermediate-range ordering

Encapsulation of Alcohol Dehydrogenase in Mannitol by Spray Drying

The retention of the enzyme activity of alcohol dehydrogenase (ADH) has been studied in various drying processes such as spray drying. The aim of this study is to encapsulate ADH in mannitol, either with or without additive in order to limit the thermal denaturation of the enzyme during the drying process. The retention of ADH activity was investigated at different drying temperatures. When mannitol was used, the encapsulated ADH was found inactive in all the dried powders. This is presumably due to the quick crystallization of mannitol during spray drying that resulted in the impairment of enzyme protection ability in comparison to its amorphous form. Maltodextin (dextrose equivalent = 11) was used to reduce the crystallization of mannitol. The addition of maltodextrin increased ADH activity and drastically changed the powder X-ray diffractogram of the spray-dried powders

Direct Treatment of Isada Krill under Subcritical Water Conditions to Produce Seasoning with Shrimp-Like Flavour

Characterization, sensory evaluation, and astaxanthin stability of isada krill under various subcritical water conditions were investigated to optimize the quality of krill extract and residue for producing food seasoning. Raw krill (82 % wet basis moisture content) without additional water was treated in a pressure-resistant vessel for 10 min at a temperature range of 100–240 °C. The yield of water-soluble protein was maximized by treatment at 200 °C and decreased with treatment at higher temperatures. The degradation of large molecules and the concomitant production of small molecules depended on the treatment temperature. Astaxanthin in the krill was unstable at temperatures higher than 140 °C. The odour intensities of krill extract and residue increased with higher treatment temperature; however, the highest intensity of pleasant shrimp-like flavour was obtained by treatment at 140 °C. Subjective preference scores were the highest for extract and residue obtained at 140 °C. Thus, treatment at 140 °C is the most promising method for production of seasoning with shrimp-like flavour from isada krill

Direct Treatment of Isada Krill under Subcritical Water Conditions to Produce Seasoning with Shrimp-Like Flavor

Characterization, sensory evaluation, and astaxanthin stability of isada krill under various subcritical water conditions were investigated to optimize the quality of krill extract and residue for producing food seasoning. Raw krill (82 % wet basis moisture content) without additional water was treated in a pressure-resistant vessel for 10 min at a temperature range of 100–240 °C. The yield of water-soluble protein was maximized by treatment at 200 °C and decreased with treatment at higher temperatures. The degradation of large molecules and the concomitant production of small molecules depended on the treatment temperature. Astaxanthin in the krill was unstable at temperatures higher than 140 °C. The odour intensities of krill extract and residue increased with higher treatment temperature; however, the highest intensity of pleasant shrimp-like fl avour was obtained by treatment at 140 °C. Subjective preference scores were the highest for extract and residue obtained at 140 °C. Thus, treatment at 140 °C is the most promising method for production of seasoning with shrimp-like fl avour from isada krill