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The purpose of this paper is to examine the efficacy of microbial elimination using different sanitizers in raw vegetables (cherry tomatoes, spring onions, Chinese chives, and chicory) and to analyze the efficacy of Escherichia coli O157:H7 reduction by type of sanitizer and vegetable.

To assess the sanitizing effects of microbial elimination by variety of vegetable, the samples were grouped into four different washing methods: control (no sanitizer), 100 ppm chlorine, 100 ppm electrolyzed water, and 200 ppm electrolyzed water after prewashing. Subsequently, quantitative microbiological experiments were conducted to assess aerobic mesophilic plate count (APC), coliform, E. coli, and Bacillus cereus, and sensory changes of the sanitized vegetables were tested. Thereafter, measurement of the sanitizing effects on bacterial reduction after inoculation with E. coli O157:H7 was conducted.

The microbial levels of four types of vegetables ranged from 3.37 to 5.24 log CFU/g for APC, 2.41 to 5.57 log CFU/g for E. coli, 0.25 to 5.40 log CFU/g for coliform, and 0.83 to 5.44 log CFU/g for B. cereus. After three types of sanitizing treatments, microbial reduction effects showed 0.94-1.84 log CFU/g for APC, 0.56-1.00 log CFU/g for E. coli, 0.18-1.26 log CFU/g for coliform, and 0.56-1.23 log CFU/g for B. cereus (p<0.05). In sensory evaluation, there were no significant differences in taste and flavor between with and without sanitizing treatments. Regarding bacterial reduction after inoculation with E. coli O157:H7, the microbial reduction on vegetables was shown to be in the range of 0.27-1.57 log CFU/g with 100 ppm sodium hypochlorite, 0.66-3.07 log CFU/g with 100 ppm electrolyzed water, and 0.79-2.55 log CFU/g with 200 ppm electrolyzed water. Chicory, cherry tomato, and spring onion showed significant reduction levels of E. coli O157:H7 after sanitation (p<0.05).

This study revealed that different sanitization methods are required for different types of vegetables. Electrolyzed water treatment (100 ppm) is a more effective and safe method of washing raw vegetables. Given that the main purpose of sanitizing fresh-cut produce is to maximally reduce microorganism levels, different methods of sanitizing fresh-cut produce with an adequate washing method should be used according to vegetable type.

Transmissible degenerative encephalopathy agents are relatively resistant to standard decontamination procedures. Bovine spongiform encephalopathy (BSE) agent was inactivated by sodium hypochlorite but not sodium dichloroisocyanurate; 1M or 2M sodium hydroxide was unreliable for BSE and scrapie agents. BSE infectivity survived a two‐year exposure to formol saline. Porous‐load autoclaving at 134‐138°C was ineffective with BSE and scrapie agents, and resistance to porous‐load autoclaving was enhanced by prior exposure to ethanol. Gravity displacement autoclaving at 132°C was also ineffective with BSE agent. Gravity displacement autoclaving at 121°C was effective with scrapie agent if it was exposed to 2M sodium hydroxide during autoclaving. After BSE‐spiked material was processed through facsimiles of EC rendering processes, infectivity was recoverable in the meat and bonemeal produced by four of these processes. Using scrapie‐spiked material, infectivity was recoverable in all meat and bonemeal samples except those derived from processes which used steam under pressure.

The purpose of this paper is to investigate the effectiveness of NaOCl and KMnO₄ at two levels in reducing the microbial load of coriander leaves.

Fresh coriander leaves procured from various markets were intensively sampled and administered to wash treatments with tap water and sanitizers at two levels. Hi media pre plated plates were used for determination of TPC (Total Plate Count), Staphylococcus aureus, Listeria, Salmonella, Shigella and coliforms.

Unwashed coriander leaves showed TPC beyond the acceptable limits of 105 CFU/g. Bulk washing (10 g sample dipped in 1 litre tap water for 5 minutes) did not significantly reduce TPC and any of the pathogens. TPC decreased significantly by 1 log cycle up on treatment with 200 ppm NaOCl and 100 ppm KMnO₄. Staphylococcus aureus could be reduced more effectively with 100 ppm of KMnO₄; Listeria monocytogenes and Salmonella showed significant reductions (P<0.05) using both sanitizers. Shigella decreased by more than 1 log cycle when treated with 100 ppm KMnO₄.

Tap water is not sufficient to reduce the microbial load of fresh coriander. Use of 100 ppm NaOCl and 50 ppm KMnO₄ may be considered to reduce the pathogenic load of coriander leaves. Since reduction of pathogenic load by 1 log cycle is insufficient, other means of disinfecting the raw produce need to be tested. Also, use of good irrigation practices and aseptic post harvest techniques cannot be ignored.

This is an original study, wherein use of sanitizers should be promoted in order to reduce the microbial load of coriander leaves.

PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses of the three GCE Boards previously discussed are analysed.

From the commencement of their use, Prodorite Ltd. have employed resin‐glass laminates to supplement the other plastics fabrication work that they are already undertaking. A number of different resins have been used to cater for a considerable variety of applications, and their range consists of a number of selected resin laminates under the heading Orglas.

Reviews some of the chemistry and environmental hazards associated with chlorine and bromine compounds when used as water disinfectants in many industrial processes. Lays emphasis on the oxidation of bromide by chlorine to bromate, a suspected genotoxin. A risk assessment of the predicted presence is detailed. In view of the formation of haloforms and other noxious substances derived from chlorine, some of the advantages of the use of chlorine dioxide are detailed. Proposes recommendations for water regulators to consider the inclusion of bromine‐containing substances, and in particular bromate, in forthcoming legislation.

Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of plastics and metals such as zirconium, titanium and tantalum. Plastics are finding extensive use as lining materials for chemical plant operating at moderate temperatures, but the poor thermal conductivity of most plastics makes them unsuitable for the transfer of heat. The recently developed metals and their alloys are extremely expensive to produce and fabricate and, so far, their use has been confined to certain specialised applications, although full‐scale production of zirconium is being carried out in America, mainly because of the low capacity of the metal for absorbing thermal neutrons. At the moment, however, these metals, because of their high cost, cannot compete commercially on a large scale with the older well‐established corrosion‐resisting alloys such as the high‐silicon iron alloys. The excellent corrosion resistance of the high‐silicon iron alloys, even at high temperatures, and their high thermal conductivity have established them as almost standard alloys for acid concentration and cooling plant construction. The following article outlines their composition and properties.

To document the drinking water component of the humanitarian response to the Great Sumatra‐Andaman earthquake of December 26, 2004, including a focus on the promotion of household water treatment (HHWT)/safe storage to minimize the spread of diarrhoeal disease.

Firsthand accounts of the response effort, interviews, and literature review.

The combined efforts to mobilize a drinking water response were timely, comprehensive and effective. HHWT/safe storage efforts (other than the continued promotion of boiling) appeared to play only a secondary role in the initial response to the disaster for a variety of reasons.

The enormity of this disaster and the unprecedented scale of the relief effort limit the broad lessons that can be learned at this time.

Shows that there is a clear need to continue to take steps to minimize the risks of waterborne diseases following natural disasters, develop and disseminate practical solutions for the special circumstances associated with tsunamis, including saline water intrusion, clarify the conditions under which proven approaches to HHWT may be useful in emergencies and assess their role in the medium‐ and long‐term response, improve water quality and surveillance without compromising emphasis on water quantity, take advantage of the enormous resources committed to the tsunami response to make effective and sustainable improvements in water, sanitation and hygiene in the affected areas, and document experiences from the tsunami response, distil the lessons learned, disseminate the results and develop guidelines to inform future actions.

Various reviews have appeared in earlier years dealing with several aspects of gelatin. Articles have also appeared dealing with the structure of the material and its properties, and with its properties in the solid state. Specifications for the purer form of gelatin have appeared in a number of Pharmacopiea, and commercial specification covering several qualities of the material have also been published.

The addition of aluminium to copper results in an improvement in the corrosion‐resisting properties of the metal; this article discusses why aluminium bronzes are noted for their performance in a number of industrial applications in which a wide range of corrosive materials—gaseous, liquid and solid—are encountered.