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The emulsifying and antioxidant properties of chicken protein hydrolysates for the physical and oxidative stabilization of chicken oil‐in‐water emulsion were investigated. The chicken protein pepsin hydrolysates obtained at reaction temperature of 33℃, 1.8% enzyme addition, liquid–solid ratio of 5:1, and reaction time of 4h, showed the DPPH radical scavenging rate of 92.12% and emulsion stability index of 0.07. The hydrolysate exerted significantly improved antioxidant activity and emulsion ability compared to the native chicken protein. The amino acid composition analysis indicated that the contents of hydrophobic amino acids including tyrosine, phenylalanine, and tryptophan were increased after hydrolysis, which contributed to the higher hydrophobicity and antioxidant activity of chicken hydrolysates. The results suggested that the chicken protein hydrolysates could be used as an alternative protein emulsifier for the production of oxidatively stable chicken oil‐in‐water emulsion. [ABSTRACT FROM AUTHOR]

Four types of roe protein isolates (RPIs) were prepared through the alkaline solubilization and acid precipitation (ASAP) process, and their functional properties and in vitro bioactivities were evaluated. Higher buffer capacity in pH‐shift range of 8–12 was found in RPI‐1 (pH 11/4.5), required average 94.5 mM NaOH than that of other RPIs to change the pH by 1 unit. All the samples of 1% dispersion (w/v) showed the lowest buffering capacity near the initial pH. The water‐holding capacities (WHC) of RPIs and casein as controls without pH‐shift were in range of 3.7–4.0 g/g protein, and there were no significant differences (p > 0.05). At pH 2 and 8–12 with pH‐shift, WHC and protein solubility of RPIs were significantly improved compared to those of controls. Foaming capacities of RPI‐1 and RPI‐3 were 141.9% and 128.1%, respectively, but those of RPI‐2 and RPI‐4 were not detected. The oil‐in‐water emulsifying activity index of RPI‐1 and RPI‐3 was 10.0 and 8.3 m2/g protein, which was not statistically different from casein (7.0 m2/g), but lower than that of hemoglobin (19.1 m2/g). Overall, RPIs, casein, and hemoglobin exhibited lower food functionality at pH 4–6 near isoelectric points. Through the pH‐shift treatment, the food functionalities of RPIs were improved over the controls, especially in the pH 2 and pH 8–12 ranges. RPI also showed in vitro antioxidant and antihypertensive activities. Therefore, it has been confirmed that RPI extracted from yellowfin tuna roe has high utility as a protein‐ or food‐functional‐enhancing material or protein substitute resource for noodles, confectionery, baking, and surimi‐based products. Fish protein isolate technology uses protein solubilization in relation to pH‐dependent properties for the separation and extraction of fish proteins from other unwanted components. Four types of roe protein isolates (RPIs 1–4) were recovered through alkaline solubilization and acid precipitation (ASAP) process, and their functional characteristics and in vitro bioactivities were evaluated. [ABSTRACT FROM AUTHOR]

This paper explores the role of Western Reserve University cardiac surgeon Claude S. Beck in convincing the world of the merits of electric defibrillation to treat the life-threatening heart arrhythmia ventricular fibrillation. Before Beck, the method of electric defibrillation had been experimentally explored at least four times but it never caught on as a medical or first-aid life-saving technique. Beck succeeded because he synchronized three activities: he refined the technique and provided clinical applications, he built a communication infrastructure, and he formulated a vision of who should use the technique under what kind of circumstances. [ABSTRACT FROM AUTHOR]

Bee‐pollen is a product collected by bees, gathered for human consumption given its nutritional and bioactive characteristics. However, its external structure is extremely recalcitrant and prevents nutrients and bioactive compounds to be completely digested into the gastrointestinal tract. The aim of this study was to assess enzymatic hydrolysis as a strategy to modify the structure of bee‐pollen and promote the release of compounds. Six different commercial enzymes were used and treatments were evaluated by Differential Scanning Calorimetry and Scanning Electron Microscopy, as well as protein, amino acids, phenolics, flavonoids, and antioxidant activity. The calorimetric analysis showed an increase in the heat flow of hydrolyzed products compared to bee‐pollen. It was also found that proteases improved the protein content of about 13%–18%, phenolics 83%–106%, flavonoids 85%–96%, antioxidant activity up to 68%, and increased all essential amino acids. Finally, a total ranking method established as the best treatment hydrolysis with Protamex. Practical applications: Bee‐pollen is an attractive food of plant origin from a nutritional and functional point of view. The modification of its structure through enzymatic hydrolysis increases the availability of compounds that theoretically could be assimilated more easily in the gastrointestinal tract, improving the quality of bee‐pollen as a food resource. The treatment is safe, relatively inexpensive and easy to apply, compared to other bee‐pollen modification strategies such as fermentation. [ABSTRACT FROM AUTHOR]