Percent Salt Research Articles

Ferric chloride treatment to control alakli induced heave in weathered red earth

A detailed experimental investigation has been carried out to study the use of ferric chloride salt to control the undesirable volume changes induced by high concentrated alkali contamination on kaolinitic red earth. X-Ray diffraction studies have revealed that soil alkali interactions produce mineralogical changes and formation of new mineral such as zeolite, which are responsible for observed swelling in non-swelling kaolinitic soil. Loss of ferric oxide, which are known cementing agents has been attributed as one of the reasons for swelling in alkali contaminated soils. The consolidation behaviour of soil compacted with 5% ferric chloride solution by weight of solutions and inundated with alkali solutions as well as soil compacted with alkali and inundated with 5% ferric chloride by weight of solutions has been studied. To study the effect of amount of ferric chloride, the volume change behaviour of soil compacted with different weight percentages of ferric salts by weight of soil (1%, 3%, and 5%) and inundated with alkali solutions has also been studied. The swelling of soil compacted with alkali has been checked by inundating with 5% ferric chloride solutions due to neutralization of alkali and is not controlled when soil compacted with 5% ferric chloride solutions is inundated continuously with alkali solutions. Further, even when the soil is treated with higher amounts of ferric chloride, in the range of 1–5% by weight of soil, the swelling is not controlled. X-ray diffraction studies have shown that the formation of zeolite is not inhibited in the presence of ferric salts.This study clearly shows that ferric chloride treatment can overcome the effects of small concentrations of alkali; it is ineffective to overcome the large and continued exposure of soils with alkali contamination.

Atmospheric aerosol composition and source apportionments to aerosol in southern Taiwan

In this study, the chemical characteristics of winter aerosol at four sites in southern Taiwan were determined and the Gaussian Trajectory transfer coefficient model (GTx) was then used to identify the major air pollutant sources affecting the study sites. Aerosols were found to be acidic at all four sites. The most important constituents of the particulate matter (PM) by mass were SO 4 2−, organic carbon (OC), NO 3 −, elemental carbon (EC) and NH 4 +, with SO 4 2−, NO 3 −, and NH 4 + together constituting 86.0–87.9% of the total PM 2.5 soluble inorganic salts and 68.9–78.3% of the total PM 2.5–10 soluble inorganic salts, showing that secondary photochemical solution components such as these were the major contributors to the aerosol water-soluble ions. The coastal site, Linyuan (LY), had the highest PM mass percentage of sea salts, higher in the coarse fraction, and higher sea salts during daytime than during nighttime, indicating that the prevailing daytime sea breeze brought with it more sea-salt aerosol. Other than sea salts, crustal matter, and EC in PM 2.5 at Jenwu (JW) and in PM 2.5–10 at LY, all aerosol components were higher during nighttime, due to relatively low nighttime mixing heights limiting vertical and horizontal dispersion. At JW, a site with heavy traffic loadings, the OC/EC ratio in the nighttime fine and coarse fractions of approximately 2.2 was higher than during daytime, indicating that in addition to primary organic aerosol (POA), secondary organic aerosol (SOA) also contributed to the nighttime PM 2.5. This was also true of the nighttime coarse fraction at LY. The GTx produced correlation coefficients ( r) for simulated and observed daily concentrations of PM 10 at the four sites (receptors) in the range 0.45–0.59 and biases from −6% to −20%. Source apportionment indicated that point sources were the largest PM 10 source at JW, LY and Daliao (DL), while at Meinung (MN), a suburban site with less local PM 10, SO x and NO x emissions, upwind boundary concentration was the major PM 10 source, followed by point sources and top boundary concentration.

A microscopic and chemical study of airborne coarse particles with particular reference to sea salt in chile at 30° s

Along a transect ranging from the Pacific to the summit of Cerro Tololo at 2200 m above sea level (a.s.l.) in Chile at 30 °S, coarse particle concentration was measured at three sites in a one-year study from December 2002 to 2003. The climate of this area is characterised by semi-arid conditions. Intensive thermally induced valley winds occurring particularly in summer, possibly transporting polluted air masses form the coastal area into the mountain region. This may question the background characteristics of Cerro Tololo as suitable site in Chile for a monitoring station of the Global Atmospheric Watch (GAW) program. Particle sampling by a passive sampling technique was employed to analyse composition of particles, find out effective sources and trace possible transport of suspended particles in this area. Temporal resolution of sampling was one week. Composition and size distribution of weekly deposition samples were determined by microscopic single particle analysis and bulk ionchromatographic analysis. Coarse particle concentration decreases differently along the transect as a function of occurring sources and depending on reactivity of components. The percentage of a black particle component remains at the same level of about 4% at all the three sites, confirming biomass burning as a wide-spread pollution. The percentage of sea salt, by contrast, amounts on average about 50% of total coarse particle concentration at the coastal area, quickly decreasing to about 10% along the transect due to losses by particle deposition and chemical reaction during transport. Ammonium shows a different behaviour, characterised by enhanced values at the central part of the transect, due to emissions from agricultural activities in this area. A shift in size distribution between the different sites is explained not only by gravitational fractionation but also by chemical conversion during transport. As a result, it is concluded that an impact of contaminated air at Cerro Tololo cannot be ruled out at a low level particularly in summer. However, the amount, composition and size distribution of the coarse fraction rather confirms the pristine area characteristics of Cerro Tololo and its background conditions.

Effects of different levels of salt and phosphate on some emulsion attributes of the common carp ( Cyprinus carpio L., 1758)

The effects of different solutions of phosphate (K 2HPO 4) and salt (NaCl) on the emulsion properties of fresh common carp ( Cyprinus carpio L., 1758) was studied by using a model system. The pH value of the minced carp, salt and phosphate slurries ranged between 6.80 and 7.53. The effects of phosphate on pH values were statistically significant ( p<0.01). Emulsion capacity (EC) of the carp meat was between 253.15 and 307.93 ml oil/g protein, and EC significantly ( p<0.01) increased with the increasing phosphate levels in the presence of 0.0 and 1.0% salt. The EC increased with salt levels but it was not statistically significant ( p<0.01). In general, emulsion stability (ES) of the treatments was between 65.13 and 77.13%. ES significantly ( p<0.01) increased with the increasing phosphate levels in the 0.0 and 2.0% salt groups. One percent salt and 0.50% K 2HPO 4 gave significantly ( p<0.01) higher ES compared to the no salt counterparts. Emulsion viscosity (EV) value of the samples was between 2500 and 5650 mPa s. EV values increased with the increasing phosphate levels in 0.0 and 1.0% salt groups, and a statistically significant ( p>0.01) difference was determined in 2.0% salt and 0.50% phosphate-containing groups. As a result, the use of carp meat in the presence of 2.0% salt and 0.50% phosphate in the processing of emulsified fish products might produce a potential raw material for better utilization of these fishes.

Fate of Staphylococcus aureus on Vacuum-Packaged Ready-to-Eat Meat Products Stored at 21°C

The U.S. Department of Agriculture has established standards for the composition and shelf stability of various ready-to-eat meat products. These standards may include product pH, moisture:protein ratio, and water activity (aw) values. It is unclear how closely these standards are based on the potential for pathogen growth or toxin production. Because the vacuum packaging used on most ready-to-eat meat products inhibits mold, Staphylococcus aureus is the pathogen most likely to grow on products with reduced aw and increased percentage of water-phase salt. In this study, 34 samples of various ready-to-eat meat products were inoculated with a three-strain mixture of S. aureus, vacuum packaged, and stored at 21°C for 4 weeks. S. aureus numbers decreased by 1.1 to 5.6 log CFU on fermented products (pH ≤ 5.1) with a wide range of salt concentrations and moisture content. Similarly, S. aureus numbers decreased by 3.2 to 4.5 log CFU on dried nonacidified jerky (aw ≤ 0.82; moisture:protein ratio of ≤0.8). Products that were not fermented or dried clearly supported S. aureus growth and cannot be considered shelf stable. The product pH and moisture:protein ratio were the two compositional factors most highly correlated (R2 = 0.84) with S. aureus survival and growth for the types of products tested, but pH and aw or pH and percentage of water-phase salt also may provide useful predictive guidance (R2 = 0.81 and 0.77, respectively).

Managing salinity in water associated with petrol industry production

This article describes a conceptual design for handling an oilfield’s industrial wastewater; its objective was to use type-I fractioned crystallisation within a feasible environmental and technical framework for obtaining the highest percentage of salt. La Gloria, La Gloria Norte and Morichal (all belonging to the Casanare department association) stations were used for planning and analysing this handling alternative as they produce high salt-containing industrial effluent. This alternative was focused on treating 30% of the total volume of the associated water so produced. This volume is expected to be 1239 m3/d in 2000 in the oilfields being studied here. The process allows 92% retrieval from present NaCl (0.918 Ton/h), having 97% purity. Evaporation and aeration systems should be set prior to the crystallisation stage as a means of guaranteeing final product quality and making good use of the field’s facilities.

Adherence to management guidelines in acute respiratory infections and diarrhoea in children under 5 years old in primary health care in Botswana

To evaluate health care providers' adherence to management guidelines for acute respiratory infection and diarrhoea in children under 5 years old in Botswana primary health care. Cross-sectional prospective field survey. Data collection was carried out through observation of consecutive consultations at 30 randomly assigned clinics and health posts in three purposely chosen districts. This study comprises 185 cases of acute respiratory infection and 85 cases of diarrhoea. Criteria for acceptable standards of history taking and physical examination for acute respiratory infection and diarrhoea were defined as well as criteria for categorizing the appropriateness of antibiotic prescription. The percentage of oral dehydration salts provided in cases of diarrhoea was calculated. Acute respiratory infection and diarrhoea accounted for 270 (including 15 missing cases) of all main diagnoses (n = 539). In 262 cases (97%) health care providers were nurses or enrolled nurses; in 3% family welfare educators. Acceptable history taking, physical examination, and both combined in acute respiratory infection was found in 113 (63%), 32 (18%), and 28 (16%), and in diarrhoea in 45 (58%), 26 (34%) and 20 (26%) cases, respectively. Antibiotics were prescribed in 76 of 255 (30%) cases. Prescription was assessed as inappropriate in 56 of 76 (74%) of all cases; in 41 of 52 (79%) cases with acute respiratory infection, in none of the pneumonia cases, and in all 15 cases of diarrhoea. Oral rehydration salts were prescribed in 74 (87%) of the diarrhoea cases. Health care providers' adherence to guidelines on history taking was suboptimal in acute respiratory infection and diarrhoea but poor on examination in both conditions. A high level of inappropriate antibiotic prescription was found in acute respiratory infection and diarrhoea. Overall, there is considerable scope for improving diagnostic and therapeutic management of these major childhood diseases in Botswana primary health care.

Inactivation by ozone of Listeria innocua on salmon-trout during cold-smoke processing

This study was conducted to evaluate the efficacy of gaseous ozone exposure on Listeria innocua 2030c growth during cold-smoke processing of Oncorhynchus mykiss (salmon-trout). Three sets of experiments were performed: inoculation with L. innocua 2030c followed by a 20 min ozone exposure were applied to (a) fresh salmon-trout after filleting, (b) to fresh whole fish, and (c) to fresh whole fish after removal of the fish slime. In sets (a) and (b) fillets were subsequently cold-smoked but not in set (c). The ozone concentration inside the exposure chamber after 20 min reached 0.1 × 10 −3 g/l. Counts of L. innocua 2030c were performed after treatment for sets (a), (b) and (c), after smoking and weekly during 21 days in vacuum packs at 5 °C, for sets (a) and (b). Sampling for total Aerobic Plate Counts (APC) of non-inoculated samples was also performed in set (a). The percentage of salt in the water phase, peroxide values and the effect of treatment on sensory properties of cold-smoked salmon-trout fillets were also determined in the first and second set. In the first set, a decrease of less than 1 log 10 in L. innocua numbers occurred on ozone treated samples in all sampling occasions. APC was slightly lower on fresh fillets after treatment and on smoked fillets at 3 weeks of storage at 5 °C (less than 1 log 10 CFU/g). In the second set, a reduction greater than 1 log 10 L. innocua/g occurred on smoked fillets at the end of the storage period. In the third set, the slime removal resulted in a 1 log 10 L. innocua/g reduction on fresh treated samples. Ozone treatment had no significant ( p > 0.05) effect on L. innocua counts on samples compared to those on untreated fish. In both sets, no significant differences among ozone treated/untreated samples were noticeable by sensory evaluation ( p > 0.05).

A New Procedure for Marinating Fresh Anchovies and Ensuring the Rapid Destruction of Anisakis Larvae

The consumption of marinated anchovies is the main route of transmission of anisakiasis in Spain. Because this country is one of the world's major tourist destinations, this traditional food also poses a potential health risk to millions of foreign visitors. Anisakis larvae are not destroyed by the traditional marinating procedure, and alternative methods, such as long-term storage in brine, freezing, or hydrostatic pressure treatment, all present major difficulties. In this study, we used high food-grade acetic acid concentrations (10, 20, 30, and 40% [vol/vol] in line with the quantum satis rule) to destroy these larvae rapidly, and we report data on the survival of Anisakis larvae exposed directly to different marinades and when the larvae are placed under the fish musculature. The percentage of salt and acetic acid in the fish tissue water phase was also determined. A marinating procedure is proposed that ensures the rapid death of Anisakis through the use of strong acetic acid concentrations. Posttreatment washes with water reduce these to levels acceptable to consumers. The sensory characteristics of the product were shown to be satisfactory. The actual selection of an acetic acid concentration for marinating depends on costs and the processing time available. The physiological stress of the larvae exposed to the different marinades was determined by measuring the levels of their stress proteins. The latter are good indicators of injury and might reflect the infectivity of larvae. In addition, we also used a rat model to determine the infectivity of larvae considered microscopically dead.

Effects of aging on rheological and proteolytic properties of goat milk Jack Cheese produced according to cow milk procedures

Pasteurized milk from French Alpine goats was processed into Jack Cheese according to modified processing conditions used for manufacturing Monterey Cheese from bovine milk. The effect of time on proteolytic and rheological changes that occurred on this cheese during aging was investigated. Commercial mesophilic culture, Lactococcus lactis subsp. lactis, was added to milk at the rate of 16 ml/100 l. The percentages of moisture, salt, protein, and fat in this cheese were 46.43, 1.19, 22.38, and 27.4, respectively. The salt to moisture ratio was 2.56. This cheese was vacuum-packed and stored at 4–5 °C for 30 weeks and the rheological and proteolytic properties were determined. The force required to compress the cheese to 20% of its original height during the first cycle increased during aging. However, the force required to compress the cheese to 75% of its original height during the first cycle did not change during aging. Similar trends were found during the second compression cycle. Elasticity values at 20% compression increased during aging; however, at 75% compression they did not change. Electrophoretic analysis of the caseins in the goat milk Jack Cheese revealed that beta casein was the most abundant casein and was less susceptible to proteolysis than other caseins. The alpha and kappa caseins were the second and the third major caseins in goat Jack Cheese, respectively. Similar to bovine gamma caseins, as beta casein was hydrolyzed in this cheese it gave rise to gamma caseins. The modified manufacturing conditions and elucidation of the chemical and physical properties of this goat milk cheese are not only providing scientific information for further research but also furnishing valuable information for practical application in production of goat milk Jack Cheese.

THE NUTRITIONAL STATUS OF PROCESSING TOMATO PRODUCTION AREAS IN MARMARA REGION

Tomato is a main crop in the southern part of Marmara region in Turkey. But, in general, yield and quality of processing tomato are not as good as expected by farmers and also industrialists. This research has been carried out to investigate nutrient status of processing tomato fields of southern Marmara region of Turkey, and it also aimed to determine the relationship between the nutrients in soil and some important soil properties. A total of 250 soil samples from 0-30 cm soil depth were taken at tomato planting time in 1999, 2000 and 2001 growing seasons. Mean clay, silt, sand, salt and organic matter percentages were 31.52, 29.89, 39.28, 0.018 and 1.59 respectively. Soil pH was mainly slightly alkaline. Total N, available P and K contents were not sufficient in most of soil samples. Among the micronutrients, only zinc was limiting. In addition, a slightly excessive boron content was found. Sand content was positively correlated (p=0,05) with available P and negatively (p=0,01) with K, Ca and Mg values. Soil pH negatively (p=0.05) affected P and Zn content only. Organic matter was positively correlated to N, Ca, Mg and Zn.

The use of dried bakery products in a free-choice feeding method for small-scale broiler production

Waste material from bakeries is an unconventional energy feed source which is available in sufficient quantities for use in small-scale broiler production in South Africa. Small-scale broiler producers do not have access to the computer programs required to balance home-mixed rations. This investigation confirms that the use of dried bakery products (DBP) in a 2-stage, free-choice method can be used to compensate for this lack. A total of 570 day-old male broiler chickens was assigned to 3 feeding treatments: the control group was fed a 2-stage feeding programme using standard commercial starter and grower rations. The 2nd group received a commercial starter ration up to Day 7 and was thereafter given a choice of a commercial starter ration with normal salt content (0.35%) and DBP. The 3rd group was fed a commercial starter ration up to Day 7, then offered a choice of commercial starter ration with a lower salt content (0.1%) and DBP. The low salt alternative was used to test whether the higher salt percentage in DBP influenced the choice of feed by the birds. It was found that the control group consumed significantly more feed (P < 0.05) and was significantly heavier (P < 0.05) than the experimental groups. However, there was no significant difference between the 2 experimental groups, which indicated that salt content did not play a role in the choice of ration. Feed consumption by both experimental groups was about one-third less than the control group, but the profit margin, as calculated using gross margin analysis, was approximately 15 % higher. It was therefore concluded that dried bakery products can be profitably incorporated as an energy feed source, using the free-choice feeding method, in small-scale broiler enterprises.

The use of dried bakery products in a free-choice feeding method for small-scale broiler production

Waste material from bakeries is an unconventional energy feed source which is available in sufficient quantities for use in small-scale broiler production in South Africa. Small-scale broiler producers do not have access to the computer programs required to balance home-mixed rations. This investigation confirms that the use of dried bakery products (DBP) in a 2-stage, free-choice method can be used to compensate for this lack. A total of 570 day-old male broiler chickens was assigned to 3 feeding treatments : the control group was fed a 2-stage feeding programme using standard commercial starter and grower rations. The 2nd group received a commercial starter ration up to Day 7 and was thereafter given a choice of a commercial starter ration with normal salt content (0.35 %) and DBP. The 3rd group was fed a commercial starter ration up to Day 7, then offered a choice of commercial starter ration with a lower salt content (0.1 %) and DBP. The low salt alternative was used to test whether the higher salt percentage in DBP influenced the choice of feed by the birds. It was found that the control group consumed significantly more feed P 0.05) and was significantly heavier (P 0.05) than the experimental groups. However, there was no significant difference between the 2 experimental groups, which indicated that salt content did not play a role in the choice of ration. Feed consumption by both experimental groups was about one-third less than the control group, but the profit margin, as calculated using gross margin analysis, was approximately 15 % higher. It was therefore concluded that dried bakery products can be profitably incorporated as an energy feed source, using the free-choice feeding method, in small-scale broiler enterprises.

Water desalination by solar powered electrodialysis process

Solar energy is a clean source of energy that is available in all regions of the world. Bahrain, where the present research was conducted, is rich in solar energy expressed as hours of sunshine which ranges between 13 h per day in the summer months to 10 h per day in the winter months. Water desalination by solar energy can be effectively achieved by using an electrodialysis process operated with photovoltaic cells. This method is attractive because electrodialysis requires a D.C. power supply as the driving force for removing the salt ions. This experimental work involved a small-scale commercial-type electrodialysis stack powered by photovoltaic cells. The stack consisted of 24 cell pairs, arranged in four hydraulic stages and two electrical stages. The feed water was fed from two sources, the first being sodium chloride solutions prepared in the laboratory and the second was groundwater of medium salinity. The experiments were done at temperatures ranging from 10 to 40 °C and product flow rates ranging from 50 to 300 gallons/day. Increasing the flow rate resulted in lower product quality given in terms of percent salt removal. Increasing the temperature generally resulted in better product quality.

Bimetallic palladium-platinum dendrimer-encapsulated catalysts.

We report the synthesis, characterization, and catalytic activity of bimetallic palladium-platinum dendrimer-encapsulated catalysts (DECs). These materials are prepared by co-complexation of different ratios of palladium and platinum salts to the interior tertiary amines of fourth-generation, hydroxyl-terminated poly(amidoamine) (PAMAM) dendrimers. Chemical reduction of these composites yields stable, fairly monodisperse, water-soluble bimetallic DECs having sizes on the order of 1.9 +/- 0.4 nm. Evidence that these nanoparticles are bimetallic comes from single-particle X-ray energy dispersive spectroscopy (EDS) and catalysis experiments. The latter indicate that the hydrogenation rate of allyl alcohol is enhanced in the presence of the bimetallic nanoparticles compared to DECs containing only platinum or only palladium nanoparticles. EDS results indicate that the percentage composition of the bimetallics is reflected by the percentage of metal salts initially complexed with the dendrimer.

Formation of alginate microspheres produced using emulsification technique.

This study investigated the formative process of alginate microspheres produced using an emulsification technique. The alginate microspheres were produced by cross-linking alginate globules dispersed in a continuous organic phase using various calcium salts: calcium chloride, calcium acetate, calcium lactate and calcium gluconate. The size, shape, drug content and Ca2+ content of the microspheres were evaluated. The tack, viscosity and pH of the calcium salt solution and percentage of Ca2+ partitioned into the organic phase were determined. Microscopic examination of the test emulsion at various stages of the emulsification process was also carried out. The propensity of cross-linking reaction was found to be dependent on successful collision between alginate and calcium salt globules. Examination of the characteristics of microspheres indicated that the formed microsphere was a resultant product of alginate globule clustering. The growth propensity of microspheres was promoted by the higher rate and extent of cross-linkage which was governed by the pH, tack and/or Ca2+ content of the cross-linking solution, as well as the dissociation constant and diffusivity of the calcium salt. Overall, the amount of free Ca2+ cross-linked with alginate in the formed microspheres was in the following order: calcium acetate > calcium chloride + calcium acetate > calcium chloride + calcium gluconate; calcium chloride + calcium lactate > calcium chloride. In microencapsulation by emulsification, the mean size of the microspheres produced can be modified by varying the tack, pH and Ca2+ content of the cross-linking solution and through the use of a combination of calcium salts. The shape of the microspheres produced was, nonetheless, unaffected by the physicochemical properties of the cross-linking solution.

Use of Grape Leaves in Canned Food

The objective of this research was to investigate suitability of fresh (unprocessed) and canned grape leaves to prepare Sarma, a traditional Turkish dish. Leaves from four different variety; Hacitesbihi, Agrazaki, Karaerik, and Kabuguyufka were blanched in two different solutions, and the leaves were placed into jars, then filled with tap water and brine containing 3.5 percent salt + 1 percent citric acid and stored for 7 months in ambient temperature. The results of chemical and physical analyses showed that quality of the Karaerik leaves was better than that of the other variety leaves. Also, sensory evaluation indicated that Karaerik and Kabuguyufka varieties were the most suitable grape leaves to produce Sarma dish. We conclude that Kabuguyufka and Karaerik leaves are convenient for Sarma dish as canned while Agrazaki and Hacitesbihi as fresh.

Use of experimental design for the purge-and-trap-gas chromatography–mass spectrometry determination of methyl tert.-butyl ether, tert.-butyl alcohol and BTEX in groundwater at trace level

An efficient method for the simultaneous determination of methyl tert.-butyl ether, tert.-butyl alcohol, benzene, toluene, ethylbenzene and xylene isomers in groundwater by purge-and-trap-gas chromatography–mass spectrometry was developed and validated. Experimental design was used to investigate the effects of temperature of extraction, time of extraction and percentage of salt added to the water samples. Regression models and desirability functions were applied to find the experimental conditions providing the highest global extraction yield. Validation was carried out in terms of limits of detection (LOD), limits of quantitation (LOQ), linearity and precision. LOD values ranging from 2.6 to 23 ng l −1 were achieved, whereas linearity was statistically verified over two orders of magnitude for each compound. Precision was evaluated testing two concentration levels. Good results were obtained both in terms of intra-day repeatability and intermediate precision: RSD% lower than 4.5% at the highest concentration and lower than 13% at the lowest one were calculated for intra-day repeatability. A groundwater sample suspected of contamination by leaking underground petroleum storage tanks was analysed and some of the analytes were detected and quantitated.

Microhabitat Segregation of Two Utah Sand Dune Tiger Beetles (Coleoptera: Cicindelidae)

The Coral Pink Sand Dunes tiger beetle (Cicindela limbata albissima) exists only within the Coral Pink Sand Dunes in southwestern Utah. It is currently a candidate for listing as an endangered species. Cicindela tranquebarica occurs throughout the southwestern United States, including the Coral Pink Sand Dunes. We examined microhabitat differences between C. l. albissima and C. tranquebarica. Results of June 1999 adult counts and measurements of percent soil moisture and salt content in 53 interdune swales indicated a significant negative correlation between soil moisture and an index of the relative number of adult C. l. albissima to C. tranquebarica, and a significant positive correlation between soil moisture and direct counts of adult C. tranquebarica. The index of relative number of adults of the 2 species was unrelated to salt content. The relative ratio of larvae of the 2 species in a given swale was significantly correlated to the relative ratio of adults of the 2 species. The cause of the observed microhabitat differences for relatively moist or dry soil could be due to a number of as yet unstudied factors including oviposition preference by the females and larval competition.

Evolution in the shoulder composition of hairless Mexican pigs throughout the curing and drying processes

The objective of this study was to analyze the chemical composition changes of the shoulders of the Hairless Mexican pigs (HMP) throughout the curing and drying processes. Shoulder composition (% of fat, protein and ash) was evaluated for moisture, water activity (Aw), pH, nitrates and sodium chloride (NaCl). Results from this study were analyzed using a descriptive analysis. Dry-curing significantly decreased Aw (raw: 0.97±0.01, dry-cured: 0.87±0.01), % of moisture (raw: 50.75±1.16, dry-cured: 31.43±1.16), pH (raw: 6.11±0.04, dry-cured: 5.82±0.04), nitrates (raw: 54.26±3.22, dry-cured: 20.03±3.22) and % of ashes (raw: 10.00±0.41, dry-cured: 8.13±0.41) throughout the process. Percentage of NaCl (raw: 0.28±0.04, dry-cured: 0.72±0.04), of fat (raw: 17.46±1.50, dry-cured: 20.53±0.11) and protein (raw: 20.63±1.34 and dry-cured: 30.21±0.95) increased significantly. The low percentage of salt and moisture and the high percentage of fat found on the final HMP shoulders suggested that the dry-curing produced a highly palatable product.