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The production of fish protein hydrolysates (FPH) is a well-established technology for the upgrading of fish by-products. However, the presence of lipids in the FPH may have adverse effects on their quality. Thus, the objective of this study was to prepare and characterise hake protein hydrolysates (HPH) from alkaline solubilised Cape hake by-products proteins previously treated with CaCl 2 and citric acid to remove phospholipids (method C). For comparison protein hydrolysates were also prepared directly from raw material (method A) and from the alkaline solubilised proteins (method B). The yields obtained in the preparation of hydrolysates by the methods B and C were considerably lower than that obtained by method A. The hydrolysates prepared by methods B and C had also lower degree of hydrolysis (DH) and protein content, but all HPH presented a well-balanced composition of essential amino acids. The methods B and C led to a high reduction of lipid content of hydrolysates (ca. 90%), however, only the method C allowed a considerable reduction of phospholipids content. HPH-A was visually lighter and HPH-C showed the highest solubility (94.3%), emulsifying activity index (11.7 m 2 /g) and emulsifying stability (97.9%). The addition of the three HPH's to minced gilthead seabream increased its water holding capacity (15.8–19.2%). HPH's exhibited angiotensin converting enzyme (ACE) inhibitory activity at 1 mg mL −1 , indicating the presence of peptides with antihypertensive activity. The method C was effective to remove phospholipids and allow obtaining HPH with good functional properties. [ABSTRACT FROM AUTHOR]

Abstract: Physical, mechanical, antioxidant and antimicrobial properties of hake protein films incorporated with citronella, coriander, tarragon and thyme oils were investigated. Dried hake proteins were solubilized at pH 11.0 (protein concentration in film forming solution ca. 0.9%) and glycerol (59% w/w of protein) and 0.25 ml of each essential oil per gram of protein was added. Films obtained were homogeneous and transparent with a yellowish colour. The addition of the different essential oils reduced the water vapour permeability but increased the solubility of films in water. The amount of protein released from the films depended on the oil added. Among all essential oils incorporated-films the thyme oil films exhibited the lowest mechanical properties (puncture force and elongation at break). Conversely, films with thyme oil added presented the highest inhibition against Shewanella putrefaciens. Antioxidant activity of hake protein films generally increased with the incorporation of essential oils as indicated by DPPH radical scavenging activity and reducing power. [Copyright &y& Elsevier]

Summary: Aims: Decreased functional capacity during aging is associated with impaired neuromuscular function. The strength training using stretch-shortening cycle exercises (SSC) is an effective way to improve performance during functional tasks. The purpose of the present study was to compare the effects of different types of strength training in the neuromuscular economy (i.e. normalized neuromuscular activity to perform the same pre training load) during functional tests in older women. Methods: Fifty older women (67±5 years) were randomly assigned into an experimental group (EG, n =33) and control group (CG, n =17). The training period lasted 6 weeks, in which EG was divided into traditional strength training (TG, n =17), and rapid strength training (RG, n =16). Results: Significant increases were observed in the 30seconds chair-stand test in both training groups, with greater changes observed in the RG compared with TG. Significant increases were also observed in isometric strength in TG (∼8%), and RG (∼10.1%), as well as in the maximal neuromuscular activity of vastus lateralis and vastus medialis in the TG and RG (P <0.05). Significant reductions were observed in the rate of rise of electromyographic signal of rectus femoris and vastus medialis in the RG after training (P <0.05). Conclusion: The strength training including SSC exercises seems to optimize the neuromuscular economy during functional activities in older subjects. [Copyright &y& Elsevier]