Journal of Food Science

A set of 13 sensory attributes for describing cooked fish were identified using data from written surveys and consumer tests. These attributes were applied to the evaluation of 18 common Atlantic species by consumers. The data showed high positive correlations with data previously reported for trained profile panels. The best correlations occurred for the most salient attributes, and cluster analysis for the two sets of data showed the greatest similarity for species possessing these salient attributes. However, regression analysis snowed that trained profile panelists used a wider range of the intensity scale than did consumers. Corresponding data from a written survey of “experts” correlated poorly with both trained and consumer panel data.

Freezing points of orange juices and model sugar‐acid‐water systems at various solute concentrations were investigated using models of solution theory. The observed freezing point depression values of citrus juice were less than those of the model system of comparable average molecular weight. The differences were characterized by a parameter which accounted for the solute‐solvent interactions. Models with generalized values were presented which allowed the prediction of equilibrium freezing curves of fruit juices based on proximate sugar‐acid composition.

The residence times of multiple particles during the flow of a non‐Newtonian suspension through a conventional holding tube assembly were compared with that in a helical holding tube assembly of identical length and tube diameter. The residence times were measured for different combinations of process parameters (viscosity, flow rate of fluid, size and concentration of particles). The effects of these parameters on Residence Time Distribution (RTD) of particles was determined and dimensionless equations were developed to predict the mean, minimum and standard deviation of residence times. The RTDs in the helical holding tube were found to be narrower than in the conventional holding tube. The RTD of particles at all combinations of process parameters were normally distributed. The ratio of mean to minimum residence time was within 1.05 to 1.11 in the helical holding tube and 1.06 to 1.16 in the conventional holding tube for the range of parameters studied.

Soy sauce was produced continuously for 80 days in 280 liter column‐type reactors containing immobilized whole cells of Pediococcus halophilus, Saccharomyces rouxii, and Torulopsis versatilis entrapped in calcium alginate gels. The divided lactic acid and alcohol fermentation by viable cells of three kinds with feed solution obtained from enzymatic hydrolyzate of koji and defatted soybean meal proceeded in shorter time than a complex fermentation of moromi (soy sauce mash) in the slurry state. The refined products fermented by this process had good taste and flavor, and were close to the conventional soy sauce with respect to organic acid and aroma components.

Phosvitin, one of the most noteworthy bioactive components of hen egg yolk, is an amphiphilic protein that stands out with its unique composition and functionality in the food industry and health. Phosvitin consists of 4% of egg yolk dry matter and 11% of egg yolk proteins. It is considered as the most phosphorylated protein with 10% phosphorus. Besides, some potential novel phosphopeptides containing clusters of phosphoserines can be derived from hen's egg yolk phosvitin. Phosvitin, which has many functional features thanks to its unique structure, is known primarily for its metal bonds binding (iron, calcium, etc.) feature. On the other hand, its phosphopeptides may increase the bioavailability of metals compared to phosvitin. Although this feature of phosvitin may partially decrease the bioavailability of especially iron in the egg, it allows the phosvitin to have many bioactivities in the food industry and health. Lipid oxidation, which is a serious problem in the food industry, can be inhibited by adding phosvitin and its derived phosphopeptides to the food production chain via inhibiting bivalent iron. Because phosvitin is an amphiphilic protein capable of chelating, it also shows potential antibacterial effects against the Gram‐negative bacteria. Moreover, the literature has recently been attempting to define the promising relationship between phosvitin and its phosphopeptides and plenty of health‐promoting activities such as immune‐enhancing, melanogenesis inhibitor, anti‐ageing, and anticancer. In this review, current information on the hen's egg yolk phosvitin and its phosphopeptides and their bioactivities in the food industry and health are discussed and some future directions are given.

The ability of Bacillus circulans peptidoglutaminase to deamidate soy proteins was investigated. Peptidoglutaminase readily hydrolyzed the γ‐amide of glutamine residues in soy peptides, but its activity toward soy proteins was low (0.4–1.3% deamidation). Molecular size and conformation of soy protein may be critical to enzymatic deamidation. Gel adsorption was used to partially purify the enzyme. Gel eluates exhibited higher acitivty than the cell extract toward soy peptides and all soy proteins but US globulin. The specific activity of the gel eluate toward 7S globulin and a water extract of soy flakes was doubled over the original cell extract.

The capacity of micellar casein isolated from bovine milk to stabilize oil in water (0:w) emulsions was studied. Emulsion surface area per unit mass of protein, i.e., emulsifying activity (EA), was highest at a protein concentration of 1% and o:w ratio of 1:9. The surface concentration of micellar casein was related to the o:w ratio being highest at an o:w of 4:6. Interfacial surface area decreased at pH 6.7 reflecting micellar stability and improved with increasing pH apparently because of destabilization of the casein micelle. Emulsion stability was high when the EA was high. The apparent viscosity of the emulsions was inversely related to EA.

The volatile flavor constituents of defatted soy flour were isolated by a specially designed apparatus. The isolated volatiles were fractionated by gas chromatography. The fractions with characteristic beany, grassy, and green odors were identified by infrared and mass spectrometry. A total of 25 compounds was identified, including nine alcohols, six aldehydes, nine ketones, and 2‐pentyl furan. Among the identified compounds, 2‐pentyl furan and ethyl vinyl ketone are probably the key compounds for the beany and grassy odors of the soy flour. All the compounds identified in this study can be postulated as autoxidative decomposition products of soy lipids. Therefore, the presence of these compounds in soy flour might be due to the incomplete removal of lipids in soy flour.