Worldwide, there is a current need for new sources of vegetable oils. The natural content of total carotenoids in Acrocomia aculeata palm oil (up to 378 µg.g-1) surpasses that of many other tropical fruits, making it one of its main compositional characteristics. As far as can be verified, there is no available information on the degradation kinetics of carotenoids for A. aculeata oil, which is required to describe reaction rates and to predict changes that can occur during food processing. The present study considered prediction abilities that have emerged with the use of specific kinetic data and procedures to understand thermal processing better, as an essential unity operation. Two kinetic mechanisms were proposed to describe the overall thermal degradation of carotenoids in the oil; the first one consists of three reaction steps while the other presents only one-step reaction. Mass balance equations were numerically solved by a Backward Differentiation Formula technique. The kinetic parameters from both models were estimated through a hybrid optimisation method using the Particle Swarm Optimization and the Gauss-Newton method, followed by statistical analyses. The model with more than one reaction was shown to be overparameterized and was discarded. The model with a single reaction was highly suited to handle the experimental data available, and the dependency of its rate constant on temperature was expressed according to Arrhenius law. As far we know, this is the first time the kinetics of carotenoids thermal degradation in A. aculeata oil is investigated through modelling simulation.

The present study was conducted to develop non-cereal starch extruded products. The effects of feed moisture (15-21%), temperature (130-170 °C) and screw speed (120-160 rpm) were evaluated on the physical and functional properties of extruded snacks using response surface methodology. Feed moisture and screw speed increased the bulk density and hardness of extruded snacks. Significant decreases in water absorption index and increases in water solubility index were observed with increases in extrusion temperature. The best conditions were determined by numerical optimization. The optimized value for non-cereal snacks for feed moisture is 18.22%, temperature 155.96 °C, screw speed 142.75 rpm and, desirability is 0.75. Verification of results showed decent agreement between the responses of experimental values at certain optimum conditions and the predicted values.

The contamination of fresh produce with antibiotic-resistant bacteria is of particular concern as they are often eaten raw and can be a source for foodborne diseases. Tetracyclines have been largely used in humans, animals and plants which might have accelerated microbial resistance to them. Enterococci and Escherichia coli can be used as indicators to monitor contamination of the fresh produce with tetracycline-resistant bacteria. The investigation related to this issue is very scarce in Oman. This study aimed at identifying tetracycline-resistant enterococci and E. coli in fresh produce at the market place. Thirty-one enterococci and ten E. coli were isolated from local (Oman) and imported fruits and vegetables (N= 105). Using the standard Kirby-Bauer disc diffusion method, resistance to tetracycline was found in 6 (19 %) enterococci, isolated from cucumber, lettuce and radish, and 5 (50 %) E. coli, obtained from cabbage, lettuce and radish. Genetic analysis revealed the presence of tetracycline resistance genes, tet(A) and tet(K), in E. coli and tet(K), tet(L) and tet(M) in enterococci, including Enterococcus sulfureus, Enterococcus mundtii, Enterococcus casseli avus and Enterococcus faecalis. The integron integrase IntI 1 gene, which is known to facilitate the dissemination of antibiotic resistance genes among bacteria, was detected in 2 isolates of E. coli. These results demonstrated the capability of fresh produce to act as a potential source for disseminating tetracycline or possibly other antibiotic-resistant bacteria through the food chain. Thus, control strategies are needed to reduce exposure of the public to such microorganisms.

Consumer trends towards shelf-stable, safe, more natural and free from additives foods drove the need to investigate the commercial application of non-thermal food processing technologies. High pressure processing (HPP) is one such emerging technology where foods are generally subjected to high pressure (100-1000 MPa), with or without heat. Similar to heat pasteurization, HPP deactivates pathogenic microorganisms and enzymes, extends shelf life, denatures proteins, and modifies structure and texture of foods. However, unlike thermal processing, HPP can retain the quality of fresh food products, with little or no impact on nutritional value and organoleptic properties. Moreover, HPP is independent of the geometry (shape and size) of food products. The retention of food quality attributes, whilst prolonging shelf life, are enormous benefits to both food manufacturers and consumers. Researches have indicated that the combination of HPP and other treatments, based on the hurdle technology concept, has potential synergistic effects. With further advancement of the technology and its large-scale commercialization, the cost and limitations of this technology will probably reduce in the near future. The current review focuses on the mechanism and system of HPP and its applications in the processing of fruit, vegetables, meat, milk, fish and seafood, and eggs and their derived products.

Membrane process is an intelligent alternative way of concentration, preferably for organic juices rich in thermolabile natural components. The expectation is to scale up the extraction of desired compounds from agro-industrial wastes through modernized concentration method. Recovery of betalains, phenolic, and antioxidant from beetroot peel extracts was accomplished by nanofiltration membrane (NF 200) at a recirculation flow rate (400 L h-1) and feed temperature (30 ºC) under constant transmembrane pressure (40 bar). Characterization of betaxanthin, betacyanin, phenolic, and antioxidant activity by spectrophotometric analysis revealed that the final samples contain these compounds respectively: 202.25±3.26 mg.L-1, 360.07±8.43 mg.L-1, 987.79±19.18 mg.L-1, 642.06±14.78 mg.L-1 (pure water); 206.62±1.37 mg.L-1, 339.72±2.89 mg.L-1, 972.72±47.49 mg.L-1, 745.97±25.45 mg.L-1 (ethanol-water). Final samples exhibit vivid colour and a considerably large amount of desired compounds compared to crude extracts and could have industrial applications.

The aim of this work was to evaluate the effects of the addition of swine skin on the technological characteristics of mortadella formulations produced on industrial scale. The effects of concentrations of swine skin (1.5 to 5.5 %) and sodium chloride (2 to 3 %) on total protein, total fat, starch, moisture, water activity, sodium, pH and texture profile (hardness, adhesiveness, elasticity, cohesiveness and chewiness) were evaluated and compared to a mortadella formulation without swine skin addition. The mortadella formulations with addition of 3.5 to 5.5 % swine skin and 2 to 2.5 % sodium chloride are in accordance with Brazilian legislation and provided an increase of approximately 12 % in protein content, a decrease of 14 % in sodium content and a water activity less than 0.9488. The swine skin and sodium chloride provided stability to the mortadella and influenced its texture, mainly in hardness, elasticity and chewiness.

Other than the edible oils extracted from the Acrocomia aculeata fruit, there is a growing interest in the palm to generate other high value-added products. Relatively high amounts of carotenoids (up to 378 mg kg-1) have been found in the esculent oils mechanically obtained from the fruit mesocarp. From industrial application perspectives, several processes have been proposed to modify native vegetable oils to yield high functional properties of structured lipids. For interesterified products, the thermal effects of industrial reactors are crucial in reaction mechanisms. The present study has taken into account previously estimated kinetic parameters for the overall disappearances of all-trans β-carotene in the Acrocomia aculeata oil (ko= 2.6 x 10-4 min-1; Ea = 105.0003 kJ mol-1; ΔH = 9.8 x 104 J kg-1) to develop a continuous stirred tank reactor (CSTR) kinetic treatment that obeys first-order kinetics. A system of ordinary dierential equations - mass and energy balances - was solved by the 4th order Runge-Kutta method (GNU Octave software). Under research conditions related to interesterification processing (2 h; 393.15 K), the initial concentration of carotenoids (around 11%) showed no significant decrease. Overall, realistic processing effects and conditions have been assessed, integrating results and knowledge, improving prospects of Acrocomia aculeata as a promising source of high-quality raw material, for producing functional ingredients and food with nutraceutical properties.

The aim of this study was to investigate the influence of raw chicken meat content on the rheological properties and 3D printability of minced meat mixtures using different concentrations of raw and cooked chicken meat. The meat mass contained yolk, crushed ice, lean raw meat and cooked meat with a high concentration of connective tissue. The concentrations of raw meat added to cooked meat as a percentage of the total weight of meat were 0; 30; 40; 50; 60; 70 and 100. To determine the rheological properties, amplitude sweep and frequency sweep were carried out with a Rheostress RS 300 (Thermo Fisher Scientific Inc.). Cubes were printed, and the printability and optical impression were evaluated using grades from 1-5. The results showed that rheological properties had a strong influence on the printability of meat mass and it is necessary for G' (storage modulus) at the LVR (linear viscoelastic region) to be higher than 7000 Pa. The complex viscosity |η*| should be higher than 170 Pa, at a shear stress τ = 10 Pa, and a frequency f = 10 Hz used to guarantee sufficient solidity.

Pasteurized fresh milk requires an accurate estimation of shelf life under various conditions to minimize the risk of spoilage and product losses. Milk samples were stored for 56 h in an oven at 25°C and for 15 days in a refrigerator at 4°C. Samples were analyzed using an electronic nose (e-nose), total bacterial count, titratable acidity and pH to determine the quality of milk. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used to analyze e-nose data of milk stored at 25°C, and 4°C. A clear shift in quality was identified by the e-nose, which also appeared in the total bacterial count after 24 h and 12 days for storage at 25 and 4°C, respectively. On the other hand, titratable acidity exceeded the normal limits of 0.14 % - 0.21 % after 24 h for storage at 25°C (0.247 ± 0.006 %) and after 15 days for storage at 4°C (0.25 ± 0.01 %). If pH was a good indicator of quality for samples stored at 25°C, it showed no clear trends for samples stored at 4°C. Based on the microbial count data and e-nose output, the milk had a shelf life of 0.3 day (i.e. 8 h) when stored at 25°C. Shelf life was extended to 9 days when stored at 4°C.

Gari (roasted fermented cassava grits) is the most popular product consumed in West Africa and an important food product in the diet of millions of people in developing countries. The study investigated the effect of packaging materials (PM) and storage periods on the functional and pasting properties of Gari produced from white-fleshed cassava roots and sensory attributes of the cooked Gari dough (eba). Gari was produced using the standard method and packaged in a polypropylene woven sack (PP) and polyvinyl chloride container (PVC). Gari was stored for 24 weeks at room temperature and sampled at four-week intervals for functional and pasting properties, and sensory evaluation of the eba, using standard methods. The results showed that the storage periods significantly affected all the functional (except swelling power) and pasting properties of the Gari, and PM had no significant (p>0.05) effect on the functional (except bulk density) and pasting properties. Also, the PM had no significant effect on the sensory attributes of the eba except for the mouldability (p<0.05). The setback viscosity of the Gari packaged in PVC had a significant (p<0.05, r= -0.58) negative correlation with the texture of the eba. The panellists preferred all the sensory attributes of the eba made from the Gari stored in PP compared to that made from Gari stored in PVC. Therefore, packaging Gari in PP may keep most of the properties preferred by consumers when stored for up to 5 months.