Analysis of virulence genes in Escherichia coli isolated from grated cheese

This research aimed to verify the presence of virulence genes in strains of Escherichia coli isolated from grated cheese sold in farmers' markets of Cuiabá-MT, Brazil. Forty samples of this food were submitted for microbiological analysis and 22 (55%) tested positive for E. coli. Next, 64 strains of E. coli were isolated from the positive samples and screened by the polymerase chain reaction (PCR) for the presence of the genes encoding the following virulence factors: stx1 and stx2 (verotoxin types 1 and 2), eae (intimin), lt1 (heat-labile toxin type 1), st1 (heat-stable toxin type 1), cnf1 and cnf2 (cytotoxic necrozing factor types 1 and 2), and cdtB (cytolethal distending toxin). All the isolates were negative for the genes stx1, stx2, eae, lt1, st1, cnf1, and cdtB, and five strains (7.81%) were positive for cnf2. A low prevalence of E. coli positive for virulence factors associated with the pathogenesis of diarrhoea was observed in this study. However, the presence of CNF-2 producing strains and the possibility of occurrence and scattering of other virulence factors that were not surveyed in the work indicate the risk related to the consumption of grated cheese from farmers' markets.

Evaluation of process parameters in the industrial scale production of fish nuggets

This work reports the use of experimental design for the assessment of the effects of process parameters on the production of fish nuggets in an industrial scale environment. The effect of independent factors on the physicochemical and microbiological parameters was investigated through a full 24 experimental design. The studied factors included the temperature of fish fillet and pulp in the mixer, the temperature of the added fat, the temperature of water and the ratio of protein extraction time to emulsion time. The physicochemical analyses showed that the higher temperature of the pulp and fillet of fish, the lower the protein in the final product. Microbiological analyses revealed that the counting of Staphylococcus coagulase positive, total and thermo-tolerant coliforms were in accordance with the current legislation.

Physiochemical analysis and centesimal composition of Pleurotus ostreatus mushroom grown in residues from the Amazon

The objective of the present work was to evaluate the nutritional composition of mushrooms produced in alternative substrates in agricultural and agro-industrial residues from the Amazon. C, N, pH, moisture, soluble solids, protein, lipids, total fibers, ashes, carbohydrates and energy were determined. Substrates were formulated from Simarouba amara Aubl. and Ochroma piramidale Cav. ex. Lam. Sawdust and from Bactris gasipaes Kunth and Saccharum officinarum stipe. Results showed that the nutritional composition of P. ostreatus varied according to the cultivation substrate and that it can be considered important food due to its nutritional characteristics such as: high protein content; metabolizable carbohydrates and fiber; and low lipids and calories contents.

Fish crackers development from minced fish and starch: an innovative approach to a traditional product

This study aimed to develop sensory acceptable, high nutritional value fish crackers that could be kept at room temperature for 180 days. Minced fish of different low-value species was the raw material employed to produce two types of fish crackers: a) the traditional keropok cracker, which was expanded by deep frying; and b) a low-fat fish cracker, expanded by microwave cooking. The protein content of the fried fish crackers (FFCs) and that of the microwaved fish crackers (MFCs) were high (10.86 and 14.70%, respectively). The essential amino acid contents of the two types of fish cracker were above the FAO requirements for adults, and the lysine content was above the requirements for children. Sensory analysis, performed by adult panelists, resulted in a general level of acceptability of 90% for the MFCs and of 97% for the FFCs. Vacuum packaging maintained microbiological and physicochemical properties for a storage period of 180 days at room temperature.

Sensory evaluation of "dulce de leche" with coffee and whey using different affective data analysis methods

This study sought to evaluate the acceptance of "dulce de leche" with coffee and whey. The results were analyzed through response surface, ANOVA, test of averages, histograms, and preference map correlating the global impression data with results of physical, physiochemical and sensory analysis. The response surface methodology, by itself, was not enough to find the best formulation. For ANOVA, test of averages, and preference map it was observed that the consumers' favorite "dulce de leche" were those of formulation 1 (10% whey and 1% coffee) and 2 (30% whey and 1% coffee), followed by formulation 9 (20% whey and 1.25% coffee). The acceptance of samples 1 and 2 was influenced by the higher acceptability in relation to the flavor and for presenting higher pH, L*, and b* values. It was observed that samples 1 and 2 presented higher purchase approval score and higher percentages of responses for the 'ideal' category in terms of sweetness and coffee flavor. It was found that consumers preferred the samples with low concentrations of coffee independent of the concentration of whey thus enabling the use of whey and coffee in the manufacture of dulce de leche, obtaining a new product.

Influence of different sanitizers on food contaminant bacteria: effect of exposure temperature, contact time, and product concentration

The efficiency of four Sanitizers - peracetic acid, chlorhexidine, quaternary ammonium, and organic acids - was tested in this work using different bacteria recognized as a problem to meat industry, Salmonella sp., S. aureus, E. coli and L. monocytogenes. The effects of sanitizer concentration (0.2, 0.5, 0.6, 1.0, 1.1 and 1.4%), at different temperatures (10 and 45 °C) and contact time (2, 10, 15, 18 and 25 minutes) were evaluated. Tests in an industrial plant were also carried out considering previously obtained results. In a general way, peracetic acid presented higher efficiencies using low concentration (0.2%) and contact time (2 minutes) at 10 °C. The tests performed in industrial scale showed that peracetic acid presented a good performance in concentration and contact time lower than that suggested by the suppliers. The use of chlorhexidine and quaternary ammonium led to reasonable results at the indicated conditions, and organic acids were ineffective under concentration and contact time higher than those indicated by the suppliers in relation to Staphylococcus aureus. The results, in general, show that the choice for the most adequate sanitizer depends on the microorganism contaminant, the time available for sanitizer application, and also on the process cost.

Application of exploratory factor analysis to assess fish consumption in a university community

The objective of this research was to use the technique of Exploratory Factor Analysis (EFA) for the adequacy of a tool for the assessment of fish consumption and the characteristics involved in this process. Data were collected during a campaign to encourage fish consumption in Brazil with the voluntarily participation of members of a university community. An assessment instrument consisting of multiple-choice questions and a five-point Likert scale was designed and used to measure the importance of certain attributes that influence the choice and consumption of fish. This study sample was composed of of 224 individuals, the majority were women (65.6%). With regard to the frequency of fish consumption, 37.67% of the volunteers interviewed said they consume the product two or three times a month, and 29.6% once a week. The Exploratory Factor Analysis (EFA) was used to group the variables; the extraction was made using the principal components and the rotation using the Quartimax method. The results show clusters in two main constructs, quality and consumption with Cronbach Alpha coefficients of 0.75 and 0.69, respectively, indicating good internal consistency.

Effects of the mechanical damage on the water absorption process by corn kernel

The purpose of this study was to investigate and model the water absorption process by corn kernels with different levels of mechanical damage Corn kernels of AG 1510 variety with moisture content of 14.2 (% d.b.) were used. Different mechanical damage levels were indirectly evaluated by electrical conductivity measurements. The absorption process was based on the industrial corn wet milling process, in which the product was soaked with a 0.2% sulfur dioxide (SO2) solution and 0.55% lactic acid (C3H6O3) in distilled water, under controlled temperatures of 40, 50, 60, and 70 ºC and different mechanical damage levels. The Peleg model was used for the analysis and modeling of water absorption process. The conclusion is that the structural changes caused by the mechanical damage to the corn kernels influenced the initial rates of water absorption, which were higher for the most damaged kernels, and they also changed the equilibrium moisture contents of the kernels. The Peleg model was well adjusted to the experimental data presenting satisfactory values for the analyzed statistic parameters for all temperatures regardless of the damage level of the corn kernels.

Ordered probit regression analysis of the effect of brand name on beer acceptance by consumers

Ordered probit regression was used to analyze data of sensory acceptance tests designed to study the effect of brand name on the acceptability of beer samples. Eight different brands of Pilsen beer were evaluated by 101 consumers in two sessions of acceptance tests: blind evaluation and brand information test. Ordered probit regression, although a relatively sophisticated technique compared to others used to analyze sensory data, was chosen to enable the observation of consumers' behavior using graphical interpretations of estimated probabilities plotted against hedonic scales. It can be concluded that brands B, C, and D had a positive effect on the sensory acceptance of the product, whereas brands A, F, G, and H had a negative influence on consumers' evaluation of the samples. On the other hand, brand E had little influence on consumers' assessment.

Okara, a soymilk industry by-product, as a non-meat protein source in reduced fat beef burgers

Okara is a by-product generated during the manufacture of soymilk and tofu. Wet okara was added to beef burgers at 0%, 20%, and 25%. The effects of okara on certain physicochemical, textural, and sensory properties of reduced fat beef burgers were investigated. The beef burgers formulated with okara (104.0-106.0 kcal/100 g) had 60% less calories than commercial beef burgers (268.8 kcal/100 g). The texture profile analysis showed that the addition of wet okara led to a significant increase in hardness (p < 0.05) and a concomitant reduction in the values of chewiness, springiness, and cohesiveness. Lower sensory scores (p < 0.05) of flavour were observed in the beef burgers containing 25% wet okara. However, the sensory evaluation results showed that juiciness, appearance, tenderness, and overall acceptability of beef burgers formulated with okara did not differ statistically from that of the control (0% okara). Wet okara (20%) can be used as a non-meat protein source in the production of reduced-fat beef burgers without changing their sensory quality.

Multivariate study and regression analysis of gluten-free granola

This study developed a gluten-free granola and evaluated it during storage with the application of multivariate and regression analysis of the sensory and instrumental parameters. The physicochemical, sensory, and nutritional characteristics of a product containing quinoa, amaranth and linseed were evaluated. The crude protein and lipid contents ranged from 97.49 and 122.72 g kg-1 of food, respectively. The polyunsaturated/saturated, and n-6:n-3 fatty acid ratios ranged from 2.82 and 2.59:1, respectively. Granola had the best alpha-linolenic acid content, nutritional indices in the lipid fraction, and mineral content. There were good hygienic and sanitary conditions during storage; probably due to the low water activity of the formulation, which contributed to inhibit microbial growth. The sensory attributes ranged from 'like very much' to 'like slightly', and the regression models were highly fitted and correlated during the storage period. A reduction in the sensory attribute levels and in the product physical stabilisation was verified by principal component analysis. The use of the affective test acceptance and instrumental analysis combined with statistical methods allowed us to obtain promising results about the characteristics of gluten-free granola.

The influence of peeling and type of drying on chemical and sensorial analysis of organic coffee

Organic coffee is characterized by being produced without the use of chemical products and by having a similar or superior quality in comparison to that of coffee produced by traditional methods. The production of organic coffee does not include the use of highly soluble nutrients, which makes consumers concerned with environmental issues and healthy eating habits realize its true value. This paper aims to analyze the influence of harvesting, peeling and drying on the quality of organic coffee, in order to present the best way of producing high quality coffee. Samples of organic coffee were harvested by both conventional and selective ways, and some were peeled. They were then dried on concrete patio and on suspended terraces. The beans were analyzed for potassium leaching, electrical conductivity, titratable acidity, and submitted to coffee cupping-test. The results obtained indicated that the selective harvesting of the peeled or unpeeled cherry coffee dried on concrete terrace is feasible for production of fine coffees. This type of processing effectively influenced the final quality of the organic coffee, thus being an alternative to improve the quality and market value of the product, especially for small producers, cooperatives, and associations of coffee producers.

Bioactive compounds and acceptance of cookies made with Guava peel flour

The use of fruit industrial waste in the processing new foods represents an important new step for the food industry. This study aimed to develop cookie recipes using different amounts of guava peel flour (GPF) levels (30%, 50%, and 70%) to evaluate the proximate composition, and the phenolic compound, lycopene, and β-carotene levels in the cookies and flour and to evaluate the cookie sensory acceptance. The results demonstrated low moisture, lipid and carbohydrate contents in the flour and cookies. GPF was considered rich in fiber, ash, polyphenols, and β-carotene. The sensory analysis showed satisfactory acceptance of the cookies containing 30% GPF regarding the aroma, flavor, and texture attributes. The cookies containing 50% and 70% GPF received satisfactory acceptance regarding to aroma only. In conclusion, GPF can be used to partially replace wheat flour in the preparation of cookies to improve the nutritional quality without affecting the product sensory quality.