Effects of the thermal denaturation degree of a whey protein isolate on the strength of acid milk gels and the dissociation of κ-casein.

In this study, the effects of the degree of thermal denaturation of whey protein (WP) added to milk on the dissociation of κ-casein from casein micelles were investigated, since they are related to the strength of acid milk gel and its factors. Acid milk gels were prepared by heating thermally denatured WP isolate (WPI) and undenatured milk mixtures and treating them with glucono-δ-lactone as a coagulant. The strength of these gels was negatively correlated with the WPI denaturation degree and strongly positively correlated with the extent of κ-casein dissociation from casein micelles. This behavior was ascribed to the fact that α-lactalbumin (α-La) and ß-lactoglobulin (ß-Lg) contained in WPI denatured after heating and engaged in disulfide bond formation with each other. With an increase in the degree of denaturation and disulfide bond formation, the bonding between ß-lactoglobulin and κ-casein was suppressed to decrease the amount of κ-casein-WPI complexes. When ß-Lg forms SS bonds with α-La, the number of highly reactive, free SH groups decreases, which complicates the formation of SS bridges between ß-Lg and κ-casein. Thus, the denaturation degree of WPI largely determined the degree of κ-casein dissociation from casein micelles and, consequently, the strength of acid milk gels. Adding WP to milk increases the strength of acid milk gel, and it can be controlled by changing the degree of thermal denaturation of the WP. Furthermore, it was clarified for the first time that the dissociation of κ-casein from casein micelles influences this effect. Further studies are needed to elucidate the structural features of κ-casein-dissociated micelles.

Endosperm enzyme activity is responsible for texture and eating quality of cooked rice grains in Japanese cultivars.

Eating quality of cooked rice grains is an important determinant of its market price and consumer acceptance. To comprehensively assess the variation of eating-quality traits in 152 Japanese rice cultivars, we evaluated activities of eight endosperm enzymes related to degradation of starch and cell-wall polysaccharides. Endosperm enzyme activities showed a wide range of variations and were lower in recently developed cultivars than in landraces and old improved cultivars. Activities of most endosperm enzymes correlated significantly with the eating-quality score and surface texture of cooked rice grains. Principal component analysis revealed that rice cultivars with high eating-quality scores had high stickiness of the grain surface and low levels of endosperm enzyme activities. These results suggest that endosperm enzyme activities control texture and eating quality of cooked rice grains in Japanese rice cultivars.

Mining online activity data to understand food consumption behavior: A case of Asian fish sauce among Japanese consumers.

Internet search engines and online recipe repositories have become increasingly popular resources among households for recipes and meal planning. Meanwhile, fish sauce's distinct flavor makes it a popular condiment in Southeast Asian countries. Although fish sauce is used as a condiment for traditional cuisine in Japan, it is not popular for general household use. To understand the consumption behavior regarding fish sauce in Japanese households, we analyzed search trends for the words nampla (Thai fish sauce), nuoc mam (Vietnamese fish sauce), and shottsuru (Japanese fish sauce) using Google's search engine and the Japanese online recipe site Cookpad. The results clearly indicate nampla's rising popularity due to the rapid spread of Thai cuisine and an annually increasing traditional consumption of Japanese fish sauce. These results provide insights into the household demand for fish sauce.

Data on volatile compounds in fermented materials used for salmon fish sauce production.

This article describes the analysis of volatile compounds in fermented materials used for salmon fish sauce production via gas chromatography/mass spectrometry (GC/MS). Ten types of fish sauces were produced from raw salmon materials, including various proportions of flesh, viscera, inedible portion (heads, fins, and backbones), and soft roe, by mixing them with salt and allowing them to ferment for up to three months. The volatile compounds were captured by a solid-phase microextraction method and then applied to GC/MS for separation and identification of the compounds in the fish sauce products. The number of volatile compounds identified in the starting materials varied from 15 to 29 depending on the ingredients. The number of compounds in the final fish sauce products was reduced by 3.4-94.7% of that in the original material. The retention times and names of the identified compounds, as well as their relative peak areas, are provided in a Microsoft Excel Worksheet.

Chemical properties and colors of fermenting materials in salmon fish sauce production.

This data article reports the chemical properties (moisture, pH, salinity, and soluble solid content) and colors of fermenting materials in salmon fish sauce products. The fish sauce was produced by mixing salt with differing proportions of raw salmon materials and fermenting for three months; the salmon materials comprised flesh, viscera, an inedible portion, and soft roe. Chemical properties and colors of the unrefined fish sauce (moromi), and the refined fish sauce, were analyzed at one, two, and three months following the start of fermentation. Data determined for all products are provided in table format.

Clustering of commercial fish sauce products based on an e-panel technique.

Fish sauce is a brownish liquid seasoning with a characteristic flavor that is produced in Asian countries and limited areas of Europe. The types of fish and shellfish and fermentation process used in its production depend on the region from which it derives. Variations in ingredients and fermentation procedures yield end products with different smells, tastes, and colors. For this data article, we employed an electronic panel (e-panel) technique including an electronic nose (e-nose), electronic tongue (e-tongue), and electronic eye (e-eye), in which smell, taste, and color are evaluated by sensors instead of the human nose, tongue, and eye to avoid subjective error. The presented data comprise clustering of 46 commercially available fish sauce products based separate e-nose, e-tongue, and e-eye test results. Sensory intensity data from the e-nose, e-tongue, and e-eye were separately classified by cluster analysis and are shown in dendrograms. The hierarchical cluster analysis indicates major three groups on e-nose and e-tongue data, and major four groups on e-eye data.

Data on the sensory evaluation of potatoes (Solanum tuberosum) from different areas of Hokkaido, Japan, performed by untrained young adults.

This data article describes a sensory evaluation of potatoes used in food processing from the Tokachi, Kamikawa, and Abashiri geographic areas of Hokkaido, Japan, performed by untrained young adults. We gathered sensory data on potatoes from the four cultivars 'Toyoshiro,' 'Kitahime,' 'Snowden,' and 'Poroshiri.' The sensory evaluation was performed on steamed potatoes from each cultivar; these potatoes were harvested from each of the three geographic areas. Table 1 provides the data from the evaluation of the five basic tastes (sweet, salty, sour, bitter, and umami), as well as the evaluation of the egumi taste, which is a Japanese term indicating a taste that is acrid, astringent, and slightly bitter.

Data on the chemical properties of commercial fish sauce products.

This data article reports on the chemical properties of commercial fish sauce products associated with the fish sauce taste and flavor. All products were analyzed in triplicate. Dried solid content was analyzed by moisture analyzer. Fish sauce salinity was determined by a salt meter. pH was measured using a pH meter. The acidity was determined using a titration assay. Amino nitrogen and total nitrogen were evaluated using a titration assay and Combustion-type nitrogen analyzer, respectively. The analyzed products originated from Japan, Thailand, Vietnam, China, the Philippines, and Italy. Data on the chemical properties of the products are provided in table format in the current article.

Data on the weights, specific gravities and chemical compositions of potato (Solanum tuberosum) tubers for food processing from different areas of Hokkaido, Japan.

This data article provides the weights, specific gravities and chemical compositions (moisture, protein, fat, ash, and carbohydrate) of potato tubers, for food processing use, from the Tokachi, Kamikawa and Abashiri areas of Hokkaido, Japan. Potato tubers of four cultivars ('Toyoshiro', 'Kitahime', 'Snowden' and 'Poroshiri') were employed in the current study. The weights and specific gravities of potato tubers from each cultivar, harvested from three areas, were measured, and those of near average weight and specific gravity from each group were analyzed for their chemical composition. In this article, weight, specific gravity, and chemical composition data are provided in tables.

Performance evaluation of peak-clipped optical BPSK-SSB modulated signal.

This study examines the performance of peak-clipped optical BPSK-SSB signal. The effectiveness of peak clipping for PAPR reduction and the degradation caused by peak clipping are numerically analyzed. PAPR of optical BPSK-SSB signal becomes high because of the peaky Hilbert-transformed signal component. PAPR improvement of 43.7% is attained by clipping the peaks of the Hilbert-transformed signal. Assessment of spectral degradation reveals that both waveform clipping and modulator nonlinearity contribute to sideband suppression degradation. Analyses of the 100-km transmitted signal results show that PAPR reduction by peak clipping alleviates the nonlinear phase shift caused by self-phase modulation (SPM), which produces a less degraded signal at the detector. Peak clipping can improve the SPM threshold of the studied system by 2.63 dB.

Characterization and emended description of Lactobacillus kunkeei as a fructophilic lactic acid bacterium.

Lactobacillus kunkeei is an inhabitant of fructose-rich niches and is a potential member of the fructophilic lactic acid bacteria. In the present study, the phylogenetic and biochemical characteristics of the type strain and eight isolates of L. kunkeei, originating from wine, flowers and honey, were studied. The nine isolates, including the type strain, formed a well-defined phylogenetic subcluster based on the analysis of 16S rRNA gene sequences. The subcluster was not closely related to other subclusters in the Lactobacillus phylogenetic group. Biochemically, the eight new isolates showed typical fructophilic characteristics. The eight isolates grew poorly on glucose, but grew well on fructose. Good growth on glucose was only recorded in the presence of electron acceptors. The type strain of L. kunkeei differed from the other isolates only on the basis of poor growth on fructose. Although they belong to a group of obligately heterofermentative lactic acid bacteria, all nine isolates, including the type strain, produced almost equimolar amounts of lactic acid and acetic acid and very little ethanol from glucose. Eight of the isolates can thus be regarded as typical 'obligately' fructophilic lactic acid bacteria. Although the type strain of L. kunkeei was phenotypically slightly different from the other isolates, it possessed several important fructophilic characteristics. On the basis of the evidence gathered in this study, the type strain of L. kunkeei is recognized as a member of the 'obligately' fructophilic lactic acid bacteria.

Large-scale production of phospholipase D from Streptomyces racemochromogenes and its application to soybean lecithin modification.

Phospholipase D (PLD) catalyzes transphosphatidylation, causing inter-conversion of the polar head group of phospholipids and phospholipid hydrolysis. Previously, we cloned PLD103, a PLD with high transphosphatidylation activity, from Streptomyces racemochromogenes strain 10-3. Here, we report the construction of an expression system for the PLD103 gene using Streptomyces lividans as the host bacterium to achieve large-scale production. The phosphatidylcholine (PC) hydrolysis activity of S. lividans transformed with the expression plasmid containing the PLD103 gene was approximately 90-fold higher than that of the original strain. The recombinant PLD103 (rPLD103) found in the supernatant of the transformant culture medium was close to homogeneous. The rPLD103 was indistinguishable from the native enzyme in molecular mass and enzymatic properties. Additionally, rPLD103 had high transphosphatidylation activity on PC as a substrate in a simple aqueous one-phase reaction system and was able to modify the phospholipid content of soybean lecithin. Consequently, the expression system produces a stable supply of PLD, which can then be used in the production of phosphatidyl derivatives from lecithin.

Influence of self-phase modulation effect on waveform degradation and spectral broadening in optical BPSK-SSB fiber transmission.

Self-phase modulation (SPM) effect is analyzed in a dispersion-compensated transmission using optical BPSK single sideband (SSB) modulation. The effect was evaluated numerically using both waveform degradation and spectral degradation, clarifying that waveform degradation is induced dominantly by peak power of the quadrature component of a Hilbert-transformed signal. Eye-opening degradation of BPSK-SSB is induced by lower fiber input power than the conventional double sideband (DSB) case because the SSB-homodyne system is sensitive to phase error resulting from SPM. Spectral degradation from SPM has two phases with increasing fiber input power. In the first phase, the sideband in the suppressive frequency region expands with increasing optical power. In the second phase, the spectral envelope in the non-suppressive frequency region becomes broad, and its shape is somewhat varied.

Fructobacillus tropaeoli sp. nov., a fructophilic lactic acid bacterium isolated from a flower.

A fructophilic lactic acid bacterium, designated strain F214-1(T), was isolated from a flower of Tropaeolum majus in South Africa. Based on phylogenetic analysis of 16S rRNA gene sequences, the strain formed a subcluster with Fructobacillus ficulneus and Fructobacillus pseudoficulneus and, based on recA gene sequences, the strain formed a subcluster with F. ficulneus. DNA-DNA hybridization studies showed that strain F214-1(T) was phylogenetically distinct from its closest relatives. Acid was produced from the fermentation of d-glucose, d-fructose and d-mannitol only. d-Fructose was the preferred sole carbon and energy source and was fermented more rapidly than d-glucose. Growth of the strain on d-glucose under anaerobic conditions was very weak but external electron acceptors such as oxygen and pyruvate enhanced growth on d-glucose. Lactic acid and acetic acid were produced from d-glucose in equimolar amounts. Ethanol was produced at very low levels, despite the strain's obligately heterofermentative metabolism. Based on these data, strain F214-1(T) represents a novel species of fructophilic bacteria in the genus Fructobacillus, for which the name Fructobacillus tropaeoli sp. nov. is proposed. The type strain is F214-1(T) ( = JCM 16675(T)  = DSM 23246(T)).

Purification, biochemical characterization, and cloning of phospholipase D from Streptomyces racemochromogenes strain 10-3.

We previously isolated Streptomyces racemochromogenes strain 10-3, which produces a phospholipase D (PLD) with high transphosphatidylation activity. Here, we purified and cloned the PLD (PLD103) from the strain. PLD103 exerted the highest hydrolytic activity at a slightly alkaline pH, which is in contrast to the majority of known Streptomyces PLDs that have a slightly acidic optimum pH. PLD103 shares only 71-76% amino acid sequence identity with other Streptomyces PLDs that have a slightly acidic optimum pH; thus, the diversity in the primary structure might explain the discrepancy observed in the optimum pH. The purified PLD displayed high transphosphatidylation activity in the presence of glycerol, L: -serine, and 2-aminoethanol hydrochloride with a conversion rate of 82-97% in a simple one-phase system, which was comparable to the rate of other Streptomyces PLDs in a complicated biphasic system.

Primary structure of potential allergenic proteins in emu (Dromaius novaehollandiae) egg white.

The emu (Dromaius novaehollandiae) egg is considered promising as an alternative egg product. To obtain basic biochemical information on emu egg white, the major protein compositions in emu and chicken egg whites and the primary structures of potential allergenic proteins were compared. The dominant protein in emu egg white was ovotransferrin (OVT), followed by ovalbumin (OVA) and TENP protein. The OVA and ovomucoid (OVM) levels in emu egg white were estimated as significantly lower than those in chicken egg white by Western blotting and enzyme-linked immunosorbent assays using anti-chicken OVA or OVM antibodies. Lysozyme and its enzymatic activity were not detected in emu egg white. OVT, OVA, and OVM genes were also cloned, and their nucleotide and amino acid sequences were determined. The protein sequences of OVT, OVA, and OVM from emu showed lower similarities to those of chicken than other avian species, such as quail and turkey. These results emphasize the low allergenicity of emu egg white and its potential as an alternative to chicken egg white.

Conservative surgical management for diffuse uterine adenomyosis.

OBJECTIVE: To determine the effects of new conservative surgical management for diffuse uterine adenomyosis. DESIGN: Retrospective clinical study. SETTING: Gynecology department in a general hospital. PATIENT(S): A total of 44 women with diffuse adenomyosis. INTERVENTION(S): Conservative surgical management. MAIN OUTCOME MEASURE(S): Mean visual analog scale score of dysmenorrhea and menorrhagia after a 3-month follow-up. RESULT(S): After this surgery, the mean visual analog scale score of dysmenorrhea decreased from 9.4 to 0.8, and anemia due to menorrhagia improved in all women. Two patients became pregnant, with one interstitial pregnancy and one normal pregnancy that is continuing. No major complications or sequelae were observed. CONCLUSION(S): This procedure should be considered as a therapeutic option in women with symptoms of diffuse uterine adenomyosis who wish to avoid hysterectomy.

Identification of actinomycetes producing phospholipase d with high transphosphatidylation activity.

Previously we isolated six actinomycetes strains, 9-4, 10-1, 10-2, 10-3, 10-6, and 21-4, that produce phospholipase D (PLD) with high transphosphatidylation activity. In this study, we identified these strains, and the PLD activities were compared with those of reference strains. 16S rDNA sequences and DNA-DNA hybridization tests indicated taxonomic affiliations of strain 9-6 with Streptomyces senoensis, strains 10-1 and 10-6 with S. vinaceus, and strains 10-2 and 10-3 with S. racemochromogenes. Strain 21-4, though identified as a Streptomyces sp., could not be identified with any known species. Meanwhile, most of the culture supernatants of reference strains demonstrated no or very weak PLD activity, while those of our strains exhibited significantly higher activity. All of the strains in this study were identified as Streptomyces species. The PLD activity of our strains exceeded most of the reference Streptomyces strains. The findings in this study imply that the Streptomyces strains, although they are members of the same species, can produce different quantities of PLD enzyme.

The primary structure of a novel riboflavin-binding protein of emu (Dromaius novaehollandiae).

Emu riboflavin-binding protein (RBP) was purified from egg white and yolk, and its N-terminal amino acid sequence was determined. The molecular mass of emu RBP was estimated at approximately 48 and 45 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, i.e., 10 kDa larger than chicken RBP. The molecular mass of deglycosylated RBPs indicated that the content of oligosaccharide chain in emu RBP was approximately 3 times greater than that in chicken RBP. The gene encoding the RBP precursor was cloned from emu oviduct cDNA by PCR and found also in the liver and ovary cDNAs as well as oviduct cDNA. The complete cDNA consisted of an open reading frame of 714 bp encoding a protein of 238 amino acids. The amino acid sequence deduced from the cDNA sequence revealed that many essential structural features were conserved in emu RBP including 18 cysteine residues, 2 N-glycosylation sites, a clustered phosphorylation region, and riboflavin-binding sites. Two additional potential N-glycosylation sites were found in the amino acid sequences of RBPs from the emu and other sources such as the turtle and frog, which might in part account for the greater content of oligosaccharide chain of emu RBP as compared to chicken RBP.