Mechanical Properties of Heat-cured Whey Protein-based Edible Films Compared with Collagen Casings under Sausage Manufacturing Conditions

ABSTRACT: Edible films were produced using whey protein isolate (WPI) (5%, w/v), glycerol (3.3%, w/v) and candelilla wax (0.8%, w/v). One set of films was heat cured at 90°C for 12 h and another at 80°C for 24 h. WPI-based films, together with collagen films, were put through a meat-processing scheme typical of Polish sausage manufacture. Meat-processing conditions were stage 1: 57°C/60 min/36% RH; stage 2: 65°C/90 min/60% RH; and stage 3: 77°C/30 min/80% RH. Effects of meat-processing conditions on mechanical properties: tensile strength (TS), elongation (%E), and apparent modulus (AM) were determined. All films remained intact throughout the process. TS, %E, and AM of collagen films did not change during the multistage cooking process. The %E of heat-cured WPI films was similar to that of collagen films and also did not change during the cooking stages. The TS and AM of both heat-cured WPI-based films were initially lower than collagen films and continued to decline during the cooking stages. TS and AM of both films at the end of cooking were lower ( P < 0.05) than films that did not go through the multistage cooking process.     

Shear Behavior of Compacted Rubber Fiber-Clay Composite in Drained and Undrained Loading

The ductility, toughness, and resistance to tensile cracking of clays can be improved with the inclusion of short fibers. Tire buffings are derived from the tire retread process and because of their elongated shape, may be used as fiber inclusions. The objective of this study was to evaluate the drained and undrained shear strength of mixtures of clay and tire buffings. Mixtures of silty low plasticity kaolinitic clay and 10% by dry weight of tire buffings were compacted at both Standard and Modified compaction energy. Consolidated-drained and consolidated-undrained triaxial tests were run at confining stresses ranging from 50?to?300?kPa. Preshear and postshear permeability tests were conducted. Results showed that the peak strength of the composite is comparable to or greater than that of clay alone when tested at confining stresses below 200–300?kPa. Above this threshold, the presence of inclusions tends to degrade the strength of the clay. Changes in permeability were not significant.     

Single stage hydrogen production from cellulose through photo-fermentation by a co-culture of Cellulomonas fimi and Rhodopseudomonas palustris

Biohydrogen production from cellulose by a bacterial co-culture is a potentially promising approach for producing bioenergy from a low cost substrate. The use of a cellulolytic bacterium, Cellulomonas fimi, permits cellulose conversion and the in situ production of substrate for growth and hydrogen production by the photosynthetic bacterium Rhodopseudomonas palustris. Response surface methodology (RSM) with a Box-Behnken design (BBD) was used to examine variations in the key parameters: substrate (cellulose) concentration, yeast extract concentration and the microorganism ratio (Rps. palustris/C. fimi). For the co-culture of R. palustris and C. fimi the highest hydrogen production (44 mmol H₂/L) was achieved at the highest substrate concentration (5 g/L); however, the highest hydrogen yield (3.84 mol H₂/mol glucose equivalent) was observed at the lowest cellulose concentration and highest microorganism ratio. High COD removal efficiencies, over 70%, were achieved over a wide range of conditions and were positively affected by the concentration of yeast extract.     

Deep Learning and Internet of Things (IoT) Based Monitoring System for Miners

Journal of Mining Science - In this study, a miner monitoring system is designed using the Deep Learning (DL) approach and the IoT technology together. It is aimed to determine the area where the...     

Inactivation of Bacillus spores in batch vs continuous heating systems at sterilisation temperatures

This study was performed to assess the heat resistance of spores of Bacillus species in batch and continuous heating systems under commercial sterilisation conditions. Spores of thermophilic Bacillus smithii and mesophilic Bacillus amyloliquefaciens were found to be highly heat resistant in the batch system. They were able to withstand typical sterilisation temperatures. B. amyloliquefaciens showed tailing in the batch system and, before the onset of the tailing, a higher inactivation rate than in the continuous system at low temperatures. The reason for the tailing might be the presence of spore aggregates which are disrupted in the continuous system.     

Inhibitory effects of selected pesticides on peroxidases purified by affinity chromatography

The objective of this study was to determine the in vitro inhibition effects of seven commonly used pesticides including 2,4-d-acid dimethylamine, fenoxaprop-p-ethyl, glyphosate isopropylamine, haloxyfop-p-methyl, cypermethrin, λ-cyhalothrin, and dichlorvos on the peroxidase purified from turnip (Brassica rapa L.) and black radish (Raphanus sativus L.) using 4-amino benzohydrazide affinity column chromatography. The purification factors for the turnip and black radish peroxidases were found to be 263.29-fold (with a yield of 12.89%) and 36.20-fold (with a yield of 6.90%), respectively. Among these compounds, λ-cyhalothrin showed the strongest inhibitory effect against turnip peroxidase (K_i: 1.23 × 10^?2 ± 0.21 × 10^?2 mM) as noncompetitive inhibition. On the other hand, cypermethrin demonstrated the highest inhibition effect against black radish peroxidase (K_i: 2.14 × 10^?2 ± 0.08 × 10^?2 mM) as competitive inhibition.     

Effects of Temperature,Time, and pH on the Stability of Anthocyanin Extracts: Prediction of Total Anthocyanin Content Using Nonlinear Models

In this study, different anthocyanin sources including grape skin, black carrot, and red cabbage were used to determine the effect of thermal treatment, different acidity levels, and time on the anthocyanin content and degradation. The total anthocyanin contents were modeled by neuro fuzzy inference system (ANFIS) and artificial neural network (ANN) models. The red cabbage anthocyanin stabilities were higher than others. The anthocyanins degraded more rapidly at higher temperatures. The anthocyanin contents of samples decreased with the increase of pH from 3 to 7. Comparison of the models showed that the ANFIS model performed better than the ANN model for the estimation of total anthocyanin content in all samples. The lowest root mean square error (0.0457) and highest R ² (0.9942) values were obtained for red cabbage and grape skin in the validation period with the ANFIS model, respectively. This study showed that both models can be utilized efficiently for the prediction of total anthocyanin content affected by temperature, time, and pH.     

Antimicrobial edible films and coatings

Increasing consumer demand for microbiologically safer foods, greater convenience, smaller packages, and longer product shelf life is forcing the industry to develop new food-processing, cooking, handling, and packaging strategies. Nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. The food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegradable protein- and polysaccharide-based edible films that can potentially serve as packaging materials. Research on the use of edible films as packaging materials continues because of the potential for these films to enhance food quality, food safety, and product shelf life. Besides acting as a barrier against mass diffusion (moisture, gases, and volatiles), edible films can serve as carriers for a wide range of food additives, including flavoring agents, antioxidants, vitamins, and colorants. When antimicrobial agents such as benzoic acid, sorbic acid, propionic acid, lactic acid, nisin, and lysozyme have been incorporated into edible films, such films retarded surface growth of bacteria, yeasts, and molds on a wide range of products, including meats and cheeses. Various antimicrobial edible films have been developed to minimize growth of spoilage and pathogenic microorganisms, including Listeria monocytogenes, which may contaminate the surface of cooked ready-to-eat foods after processing. Here, we review the various types of protein-based (wheat gluten, collagen, corn zein, soy, casein, and whey protein), polysaccharide-based (cellulose, chitosan, alginate, starch, pectin, and dextrin), and lipid-based (waxes, acylglycerols, and fatty acids) edible films and a wide range of antimicrobial agents that have been or could potentially be incorporated into such films during manufacture to enhance the safety and shelf life of ready-to-eat foods.     

Functional Properties of Vinegar

A variety of natural vinegar products are found in civilizations around the world. A review of research on these fermented products indicates numerous reports of health benefits derived by consumption of vinegar components. Therapeutic effects of vinegar arising from consuming the inherent bioactive components including acetic acid, gallic acid, catechin, ephicatechin, chlorogenic acid, caffeic acid, p‐coumaric acid, and ferulic acid cause antioxidative, antidiabetic, antimicrobial, antitumor, antiobesity, antihypertensive, and cholesterol‐lowering responses. The aims of this article are to discuss vinegar history, production, varieties, acetic acid bacteria, and functional properties of vinegars.