Dielectrical,microstructural and flow properties of sauce model systems based on starch,gums and salt

The dielectric properties of salted systems based on different hydrocolloids (native or modified starches, or on ι, λ, or κ carrageenan) as models for microwaveable white sauces were studied. Microstructural and rheological properties were also studied to better understand the dielectric behaviour.     

Effect of batter formulation on lipid uptake during frying and lipid fraction of frozen battered squid

The present paper studies the influence that batter ingredients (wheat flour, corn flour, salt and leavening agent) have on fat content and oxidative degradation of the lipid fraction of deep-fried frozen battered squid. The use of a leavening agent significantly increases the fat content during frying; the generation of gas cells where oil easily lodges is the most important event observed by scanning electron microscopy when this additive is used in the formulation. The addition of salt in the formulation also increases fat content, but replacement of wheat flour by corn flour decreases significantly the oil content of the battered squids. The acidity index values indicate a relatively low degree of hydrolysis for all the batters studied. The batter formulation influences the degree of oxidation of the lipid fraction of the deep-fried products; the battered product with leavening in its formulation shows a lesser oxidation (P<0.05), which might be connected with the high absorption of oil during deep fat frying.     

Improvement of crunchiness of battered fish nuggets

In this study, two strategies to improve the crunchiness of fish nuggets for microwave final cooking were employed: addition of dextrin into batter formulation, and using a package containing a susceptor material, which improves heat transmission and increases the temperatures reached in the microwave. In this work, two dextrins (one of high solubility and other of medium solubility) were used to study their effect in battered, prefried fish nuggets, finally cooked by three different procedures: deep frying, microwaving and microwaving with susceptor packaging. In addition, all tests were performed with and without batters containing methylcellulose in order to assess the effect of oil uptake. The crunchiness of fish nuggets was evaluated by a recently developed method which simultaneously registered texture and sound measurements during the cutting of the nuggets. The profiles of the fried nuggets had numerous force and sound peaks and a typical jagged plateau shape, whereas those of the microwaved samples had force peaks that disappeared and the profiles adopted a smooth ascending curve. However, the use of the susceptor slightly improved the number of sound peaks. In addition, sensory crunchiness and other sensory attributes were measured by a trained panel. When the dextrins-containing nuggets were cooked by microwave and susceptor, they were perceived as crunchier as and oilier than the other samples.     

Synthetic peptides corresponding to various hydrophilic regions of the large subunit of cytochrome b558 inhibit superoxide generation in a cell-free system from neutrophils

The role of capsule expression in the capacity of Escherichia coli to colonize in the large intestinal environment was studied in a gnotobiotic rat model. The rats were given perorally a mixture of two mutant strains differing in K5 expression. After 2 weeks, the rats were sacrificed, and subsequently intestinal contents, intestinal mucosae, and mesenteric lymph nodes were homogenized and bacterial numbers were quantified. Two E. coli mutant pairs were used, the first pair (972-998) lacking the O-specific side chain and the second pair (973-997) carrying the O75 lipopolysaccharide. The K5+ mutants established themselves at a higher level than the K5- mutants (10(9) versus 10(6) CFU/g [P < 0.001] for the first pair and 10(9) versus 10(8) CFU/g [P < 0.01] for the second pair, respectively). The results were confirmed by serology showing a K5+ phenotype for practically all isolates. The bacterial population associated with the mucosa was similar to that in the luminal contents with respect to the proportions of the respective mutants, and translocation occurred in numbers proportional to the intestinal population densities of the respective mutants. All mutants were able to express type 1 as well as P fimbriae. After colonization, the expression of P fimbriae remained high whereas only a minority of the isolates expressed type 1 fimbriae. The results suggest that capsule expression and P fimbriae enhance intestinal colonization by E. coli and that these virulence factors, by increasing bacterial densities in the intestine, secondarily increase translocation.