Formation risk of toxic and other unwanted compounds in pressure-assisted thermally processed foods.

Consumers demand, in addition to excellent eating quality, high standards of microbial and chemical safety in shelf-stable foods. This requires improving conventional processing technologies and developing new alternatives such as pressure-assisted thermal processing (PATP). Studies in PATP foods on the kinetics of chemical reactions at temperatures (approximately 100 to 120 °C) inactivating bacterial spores in low-acid foods are severely lacking. This review focuses on a specific chemical safety risk in PATP foods: models predicting if the activation volume value (V(a) ) of a chemical reaction is positive or negative, and indicating if the reaction rate constant will decrease or increase with pressure, respectively, are not available. Therefore, the pressure effect on reactions producing toxic compounds must be determined experimentally. A recent model solution study showed that acrylamide formation, a potential risk in PATP foods, is actually inhibited by pressure (that is, its V(a) value must be positive). This favorable finding was not predictable and still needs to be confirmed in food systems. Similar studies are required for other reactions producing toxic compounds including polycyclic aromatic hydrocarbons, heterocyclic amines, N-nitroso compounds, and hormone like-peptides. Studies on PATP inactivation of prions, and screening methods to detect the presence of other toxicity risks of PATP foods, are also reviewed.

Reuse of ozonated alkaline solutions as fermentation brines in Spanish green table olives.

The water used to reduce the excess NaOH after the immersion of green olives in lye becomes a heavily polluted, alkaline wastewater (AW) once it has come into contact with the fruits. Its treatment with ozonated air for 72 h (TAW) destroyed all polyphenols in the solution. A comparison of the microbial, physicochemical, and organoleptic characteristics of olives processed in the traditional way (W) and those reusing AW or TAW was made. The reuse of TAW or diluted TAW (TAW + W) as fermentation brines led to a shorter lag phase, higher maximum specific growth of lactobacillus, and higher lactic acid accumulation (in TAW) than the traditional process; differences among other physicochemical characteristics were not relevant, except that reused brines (AW) always had higher polyphenol contents. The organoleptic panel test did not detect significant differences among treatments in acidic taste, firmness, pit detachment, or olive color. Overall quality was fairly similar for olives from the traditional process and those from the reused TAW. Direct (or diluted) reuse of AW was also possible but produced a more bitter tasting olive.

Treatment of green table olive solutions with ozone. Effect on their polyphenol content and on Lactobacillus pentosus and Saccharomyces cerevisiae growth.

Disposition of green table olives alkaline solutions (GTOS) remains a major task for the industry with serious environmental implications. The presence of high concentrations of polyphenols in olives also presents a problem for direct brining and successful fermentation step. In this study we evaluated the effect of ozone treated GTOS on the growth of Saccharomyces cerevisiae and Lactobacillus pentosus. GTOS were treated with ozone for 24 and 72 h. The treatment caused a rapid destruction of polyphenols but did not affect sugar concentration. S. cerevisiae grew in the original and treated liquids, although its maximum specific growth rate (mu(m)) and its population size increased as the ozone treatment was longer. L. pentosus was completely inhibited in the original and 24 h ozone treated GTOS, but grew in 72 h treated solutions. Co-culture with S. cerevisiae improved L. pentosus performance. Diluting the original GTOS with distilled water in several ratios, and adding MRS medium (50 g/L) to ensure nutrient availability, showed that a complete inhibition on L. pentosus did never occur; however, its mu(m) progressively increased, and the lag phase period (lambda) decreased linearly, with increasing dilutions levels. The inhibition effect was lower in 24 h ozone treated GTOS and disappeared completely in those treated for 72 h. Furthermore, treatment of GTOS with ozone always improved microbial growth.

Stretch expanded polytetrafluoroethylene graft with intrawall radial support system: an advance in vascular access graft design.

Vascular access expanded polytetrafluoroethylene (ePTFE) grafts with external support systems consisting of parallel rings or in a spiral configuration are designed to resist kinking and compression at the apex of loop grafts or when crossing a joint. However, during the implantation procedure, the rings or spiral must be removed from the portion of the graft that is cut to allow the graft to be divided at the desired angle and suture the anastomosis. A new ePTFE graft (Intering) with an intrawall radial support system and a smooth lumen permits easy division of the support segments at the chosen angle. Moreover, minimal resistance is encountered during suturing of the graft. The results of early experience with Intering grafts crossing the elbow joint, in short-segment revisions, and in primary forearm loop configurations are encouraging.

Capital planning: investing in excellence.

Graham Slater and Kate Del Bravo describe the priorities considered and work undertaken by SETRHA to develop its capital investment strategy. Although the underlying concepts are straightforward, it represents a significant development beyond traditional NHS approaches to planning, embraces the NHS market reforms, and has reduced capital aspirations for the same service objectives by some 300m pounds.