Defatted mustard seed meal-based biopolymer film development

Edible films were developed from a defatted mustard seed meal (Sinapis alba) (DMM), a byproduct from the bio-fuel industry. Films were formed by casting DMM suspensions (3-g DMM/100-g suspension) that were treated by high-pressure homogenization (HPH, 138 MPa), ultrasound (400 W, 30 min), or gamma irradiation (10 or 20 kGy), and mixed with glycerol and soy lecithin. Rheological properties, water vapor permeability, water solubility, tensile strength (TS), percentage elongation (%E), elastic modulus (EM), color, and structural properties of film-forming suspensions or films were determined. Films were successfully produced using the HPH-processed suspension with 0.6% glycerol. Rheology results indicated the polymer network structure of the film-forming suspension was loosened by HPH, but tightened by heating at 90 °C. The ranges for the properties of WVP, WS, TS, %E, and EM of the films were 3.4-5.0 g mm/kPa h m², 30.3-34.4%, 1.3-5.5 MPa, 0.9-18.1%, 33.2-294.7 MPa, respectively. L, a, and b by CIELAB coordinates were 73.3-77.9, 0.4-3.5, and 29.5-45.7, respectively. HPH increased TS and %E of the films and decreased EM, whereas the ultrasound and the 20 kGy-irradiation treatments increased %E and decreased EM. The TS and EM decreased and E% increased with increasing glycerol and soy lecithin. DMM is a promising material to produce edible biopolymer films and coatings for food packaging.     

Simultaneous determination of fragmentation and coalescence rates during pilot-scale high-pressure homogenization

The emulsification process is primarily determined by the rate of fragmentation and coalescence of emulsion drops. However, there is presently no fast, reliable method for measuring these rates for pilot and production scale high pressure homogenizers.     

Effect of pH,temperature and maturity on pectinmethylesterase inactivation of citrus juices treated by high-pressure homogenization

The effects of high-pressure homogenization (HPH) at 150 MPa combined with heating at 58, 63 and 68 °C on inactivation of pectinmethylesterase (PME) were studied in orange and Clementine juices. Juices covering a range of total soluble solids (°Bx) to acid ratios (10.2–15.0 in oranges and 9.2–19.4 in Clementines) were adjusted to pH 3.1, 3.5 and 3.9 before homogenization. Results indicated how the residual PME activity of homogenized samples was greatly attenuated by lowering the pH and in a lesser extent by increasing the homogenization temperature (finding orange enzymes more HPH sensitive than their Clementine counterparts). Generally, ripeness of fruits had little influence on PME inactivation (especially in Clementine juices). In any case, orange and Clementine samples with pH 3.1 and homogenized at 68 °C showed residual PME activities below 10% of the initial value from their respective fresh juices.     

Effect of high-pressure homogenization on microstructure and rheological properties of alkali-treated high-amylose maize starch

The effect of high-pressure homogenization (HPH) on the microstructure, rheological properties, paste clarity, as well as gel retrogradation behavior of alkali-gelatinized high-amylose maize starch (HMS) was investigated. The alkali-treated HMS pastes were subjected to HPH at homogenizing pressures of 25, 50, 75, 100, and 125 MPa. After HPH treatment, the uniformity in the microstructure of HMS pastes was greatly increased. At homogenizing pressures greater than 100 MPa, starch ghost particles were found to completely disappear. The apparent viscosity of the HMS pastes was found to decrease significantly due to the application of HPH. The paste clarity of the HMS pastes increased when HPH treatment was applied. After storing at 4 °C for 7 days, HMS pastes homogenized at 50 and 100 MPa displayed weaker viscoelastic behavior than their corresponding unhomogenized pastes. This indicated that HPH treatment is capable of inhibiting starch retrogradation in gels.     

Emulsifying properties of collagen fibers: Effect of pH,protein concentration and homogenization pressure

The emulsifying properties of collagen fibers were evaluated in oil-in-water (O/W) emulsions produced under different conditions of pH, protein content and type of emulsification device (rotor–stator and high-pressure homogenizer). The stability, microstructure and rheology of the O/W emulsions were measured. The phase separation and droplet size of the emulsions prepared using the rotor–stator device (primary emulsion) decreased with protein concentration and reduction in pH, allowing the production of electrostatically stable emulsions at pH 3.5. In contrast, emulsions at higher pH values (4.5, 5.5 and 7.5) showed a microscopic three-dimensional network responsible for their stability at protein contents higher than 1.0% (w/w). The emulsions at pH 3.5 homogenized by high pressure (up to 100 MPa) showed a decrease in surface mean diameter (d₃₂) with increasing pressure and the number of passes through the homogenizer. These emulsions showed droplets with lower dispersion and d₃₂ between 1.00 and 4.05 μm, six times lower than values observed for primary emulsions. The emulsions presented shear-thinning behavior and lower consistency index and viscosity at higher homogenization pressures. In addition, the emulsions showed a less structured gel-like behavior with increase in homogenization pressure and number of passes, since the pressure disrupted the collagen fiber structure and the oil droplets. The results of this work showed that the collagen fiber has a good potential for use as an emulsifier in the food industry, mainly in acid products.     

Effect of high-pressure homogenization, nonfat milk solids, and milkfat on the technological performance of a functional strain for the production of probiotic fermented milks

The aim of this research was the evaluation of the effects of milkfat content, nonfat milk solids content, and high-pressure homogenization on 1) fermentation rates of the probiotic strain Lactobacillus paracasei BFE 5264 inoculated in milk; 2) viability loss of this strain during refrigerated storage; and 3) texture parameters, volatile compounds, and sensorial properties of the coagula obtained. The data achieved suggested a very strong effect of the independent variables on the measured attributes of fermented milks. In fact, the coagulation times were significantly affected by pressure and added milkfat, and the rheological parameters of the fermented milk increased with the pressure applied to the milk for added nonfat milk solids concentrations lower than 3%. Moreover, the polynomial models and the relative response surfaces obtained permitted us to identify the levels of the 3 independent variables that minimized the viability loss of the probiotic strain used during refrigerated storage.     

Improving ground beef safety and stabilizing color during irradiation using antioxidants, reductants or TSP

The objective of this research was to extend ground beef retail display life using antioxidants, reductants, and/or TSP treatments combined with electron beam irradiation. Ground beef was produced with added butylated hydroxyanisole (BHA) plus butylated hydroxytoluene (BHT) with the following combinations; (1) ascorbate; (2) trisodium phosphate(buffer); (3) erythorbate; (1) and (2); (1) and (3); (1), (2), and (3); and an untreated control, C. Half of the treated samples were irradiated (I) at 2.0 kGy-absorbed dose under a nitrogen atmosphere, half remained non-irradiated (N). Samples were displayed under atmospheric oxygen and evaluated for total aerobic plate count (TPC), thiobarbituric acid reactive substances (TBARS) and instrumental color during 9 d of simulated retail display (SRD). Controls had the highest (P < 0.05) TBARS value and the lowest (P < 0.05) redness (CIE a*), proportion of oxymyoglobin and vividness. Treated irradiated samples were just as red and vivid on SRD day 9 as the non-irradiated untreated control at day 0. Treatments stabilized color and lipids of ground beef after irradiation and during SRD.     

Phenolic profile,antioxidants, and sensory acceptance of bioactive-enhanced peanuts using ultrasound and UV

Phenolic antioxidant compounds, including resveratrol, are associated with reduced risk of cancer and cardiovascular disease, and delayed ageing. This study aims to quantify synergistic enhancement of phenolics and antioxidants in peanuts by combinations of ultrasound (US)–UV treatments, compared to either US or UV, and determine optimum parameters for combined US–UV process. LC–MS confirmed the bioactive phenolics: trans-resveratrol, trans-piceid, and p-coumaric-, caffeic-, and ferulic-acids, which achieved maximum increases, with combined US–UV, compared to US or UV; as did total phenolics (TP), TEAC, and ORAC. Optimum parameters for a combined US–UV process will provide up to 4.8 μg/g trans-resveratrol, 170 μg/g p-coumaric acid, and 150 μM TE/g ORAC or >100% that found in red wines; 1.0 μg/g trans-piceid, 2.6 μg/g ferulic acid, 1.48 mg GAE/g TP, and consumer acceptance ?5. Optimum combined US–UV resulted in 1.3× or 2.3× the trans-resveratrol concentrations in US or UV, respectively, suggesting synergistic effect of UV and US in enhancing resveratrol in peanuts.     

Potato starch edible films to control oxidative rancidity of polyunsaturated lipids: effects of film composition, thickness and water activity

The objective of this work was to study the effect of potato starch-based films acting as oxygen barrier on the oxidative rancidity of vegetable oil, as an example of a food rich in polyunsaturated fatty acids. The effect of glycerol (Gly) content (0%, 10%, 20%, 30%), film thickness (30, 60, 100 μm) as well as environmental relative humidity (RH) (50% or 75%) were analysed. Results obtained confirmed that potato starch films delayed the rancidity in vegetable oil. Films without Gly provided the same protection as films with 10% Gly. Films with higher Gly content were not as effective oxygen barrier. It is likely that the fact that film protective capability diminished with increased RH or Gly content was due to the increasing moisture content of the films. Despite that fact, potato starch films can be considered a very efficient oxygen barrier even at RH as high as 75%.     

Simultaneous shade development,antibacterial, and antifungal functionalization of wool using Punica granatum L. Peel extract as a source of textile dye

In this work, we investigated the use of pomegranate peel extract as an effective functional dye for producing beautiful natural shades on wool and to impart durable antimicrobial properties. Wool is treated with various metal salt mordants in the presence of pomegranate dye under optimum natural dyeing conditions. The structural changes of wool are characterized by SEM and FT-IR techniques. The properties of color strength, color fastness to light, washing, rubbing, and durability of antimicrobial activity to washing are investigated. The experimental results indicate that there is small color variation among shades obtained under identical dyeing conditions. Furthermore, it was found that metal salt mordants improved dyeing depth, fastness properties, and effectively enhanced the durability of antimicrobial activity up to several washing cycles.     

Structure (micro, ultra, nano), color and mechanical properties of Vitis labrusca L. (grape berry) fruits treated by hydrogen peroxide, UV–C irradiation and ultrasound

Main structural (micro, ultra, and nano) alterations occurred in the outer tangential epidermal cell wall of Vitis labrusca L. fruits (grape berry) due to hydrogen peroxide, UV–C irradiation and ultrasound treatments were examined, and described using light microscopy, scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Changes in mechanical properties and surface color were also evaluated. In general, decontamination treatments caused epicuticular wax pattern alteration, epicarp disruptions, cell plasmolysis, and mesocarp collapse. Major observed ultrastructural and nanostructural changes were increased demarcation between cellulose layer and cuticular membrane, alteration of cellulose aggregates pattern, and presence of nanofractures, variables in shape and size. All treatments, mainly ultrasound, provoked significant but small differences in color parameters compared to untreated fruit. On contrast, mechanical properties determined by puncture test did not vary.