The potential of DBD plasma pretreatment for the isolation of micro- and nano-cellulose fibers from the walnut shells.

This study investigated the use of dielectric barrier discharge (DBD) plasma as a pretreatment to extract micro and nano-cellulose fibers from walnut shells (WS). The powdered WS was subjected to plasma at 18 and 20 kV before undergoing sodium hydroxide alkaline, sodium chlorite bleaching, or both alkaline and bleaching treatments. A control sample was also prepared without plasma treatment. The extracted cellulose was then analyzed for extraction efficiency, chemical composition, color, crystallinity index, FTIR, thermal properties, microstructure, and surface composition. The results showed that the plasma pretreatment reduced the cellulose extraction efficiency from ∼26 % to ∼22 % which was accompanied by a decrease in the C-C/C-H and C-OH/C-O-C bonds. The 20 kV plasma pretreatment prior to both alkaline and bleaching treatments resulted in the conversion of microfibrils into nanofibrils, with an average diameter of 80 ± 10 nm. These changes in the fiber structure were likely caused by the disruption of hydrogen-bonding interactions in the plasma-treated samples, leading also to a reduction in crystallinity index. The plasma-treated sample exhibited a different weight loss pattern below 100 °C compared with the control, originating from changes in water absorption. Overall, the study demonstrated that plasma pretreatment can successfully produce micro and nano-cellulose fibers from WS.

Conjugation of soy protein isolate with carboxymethyl cellulose through dielectric barrier discharge (DBD) plasma.

The present study aimed to evaluate the physicochemical properties of dielectric barrier discharge (DBD) plasma grafted carboxymethyl cellulose (CMC) and soy protein isolate (SPI). Therefore, the mixture of SPI and CMC was treated at 16, 18 and 20 kV for 5, 10 and 15 min with DBD plasma. The results of FTIR, XRD, FESEM and SDS-PAGE confirmed the SPI-CMC conjugate formation after plasma treatment, and a glycation degree of about 21 % was obtained after 15 min treatment at 18 kV. Significantly higher levels of emulsifying activity and stability, as well as solubility, were obtained for the conjugates, as compared with the SPI-CMC mixture. Also, the smaller droplet sizes were observed in emulsions obtained from conjugate produced at 18 kV for 5 min, which had the most stability after 14 days of storage at 4 °C. Eventually, it was detected that DBD plasma could graft SPI and CMC in a short time.

Effects of nomadic grazing system and indoor concentrate feeding systems on performance, behavior, blood parameters, and meat quality of finishing lambs.

The objective of the study was to evaluate the effects of three production systems on growth performance, behavior, blood parameters, carcass characteristics, and meat quality. A total of 30 lambs (n = 10 lambs/treatment) were randomly assigned to three production systems that included rotational grazing (NG) and two different levels of concentrate (CON), one with medium (roughage/concentrate ratio 50:50% based on DM, MC) and one with high concentrate (roughage/concentrate ratio 30:70% based on DM, HC) during the 90-day fattening period. At the start of the experiment, all lambs averaged 90 ± 4 days of age (mean ± SD) and were slaughtered at an average of 180 ± 3 days (mean ± SD). CON-fed lambs had higher average daily gain and loin thickness than NG-fed lambs. The NG lambs spent more time eating, drinking, and standing, but less time resting and rumination than the CON-fed lambs. In addition, plasma lipid, ß-hydroxybutyrate, and urea levels were higher, while phosphorus levels were lower in NG-fed lambs than in CON-fed lambs. CON-fed lambs had better carcass yield, but gastrointestinal tract and rumen weights were lower than NG lambs. CON-fed lambs had higher pH values 0 h post mortem than the NG lambs; however, there was no effect of treatment on pH 24 h post mortem. The post-mortem color of the LD muscle of NG lambs had a higher lightness and yellowness index and a lower redness index than that of the LD muscle of CON-fed lambs. The results of this study showed that lambs fed CON had better carcass yield than lambs fed NG, although feed intake, feed conversion ratio (FCR), growth performance, carcass yield, and meat quality of lambs fed MC and HC were similar.

Physicochemical properties of beef burger after partial incorporation of ethylcellulose oleogel instead of animal fat.

The aim of this study was to evaluate the physicochemical properties of beef burger after substitution of animal fat with the ethylcellulose (EC) oleogel. Therefore, sesame oil oleogels were prepared using EC in concentrations of 10%, and cooled at 25 °C. The fatty acid profile of EC oleogel compared with animal fat. Then, the EC oleogel was incorporated to hamburger at the 0, 25 and 50% instead of animal fat and color and textural properties as well as cooking loss, cooking shrinkage, fat absorption, and lipid oxidation of the beef burgers were evaluated. As an outcome, the EC oleogel contained high levels of linoleic and linolenic acids, while the palmitic and stearic acids were lower than the animal fats, and myristic acid was not detectable. Replacement of animal fat with EC oleogel upgraded the quality of final product by reducing cooking loss and fat absorption. Production of beef burger with EC oleogel decreased the oxidation process during frozen storage as well as cooking loss and fat absorption, and enhanced textural properties including chewiness and hardness. Improvement of nutritional and technological properties of hamburgers contained EC oleogel makes it a desirable candidate for animal fat substitution. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at(10.1007/s13197-021-04970-4).

Application of high-intensity ultrasonic radiation coupled with papain treatment to modify functional properties of beef Longissimus lumborum.

The present study aims to develop a novel process for improving the functional properties of beef. For this purpose, the effect of high-intensity ultrasound, alone and in combination with papain was investigated on pH, water-holding capacity (WHC), emulsion capacity and stability, cooking loss, and gelling property of Longissimus lumborum muscle. Meat samples were subjected to sonication (20 kHz, 100 and 300 W) for 10, 20 and 30 min in the presence and absence of papain solution. Results indicated that the application of ultrasound individually or in combination with papain significantly influenced on the functional properties of beef. For all tested samples compared with the untreated meat, there was a significant increase in the WHC, emulsion capacity and stability and a significant decrease in cooking loss. Generally, our findings suggest that the combination of ultrasound and papain was more beneficial for improving functional properties of meat compared with the individual treatment.

Effects of edible coating containing nano-emulsion of Aloe vera and eugenol on the physicochemical properties of shrimp during cold storage.

BACKGROUND: Shrimp is nowadays recognized as a rich source of proteins and omega-3 fatty acids. Edible nano-emulsion coatings containing eugenol, as an antioxidant agent, and Aloe vera, as a functional compound, were prepared for the storage of pink shrimp over 7 days at 277 K. Samples of the nano-emulsion were prepared under ultrasonication using 0, 10 and 20 g L-1 of Aloe vera as well as 0, 15 and 30 mL L-1 of eugenol along with Tween 80. RESULTS: Results indicated that the low pH of Aloe vera reduced that of the nano-emulsions while the particle size and turbidity increased with increasing Aloe vera concentration. Moreover, both colour and antioxidant activity of the nano-emulsions were significantly affected by eugenol and Aloe vera concentrations (p < 0.05). Increasing eugenol concentration led to increased nano-emulsion pickup but to reduced lightness. Higher concentrations of Aloe vera significantly (p < 0.05) decreased drip loss, cooking loss, pH rise and oxidation rates but enhanced hardness in the shrimp samples. CONCLUSIONS: The best results were recorded for the nano-emulsion coating containing 30 mL L-1 of eugenol and 20 g L-1 of Aloe vera. The nano-emulsion was successfully able to upgrade shrimp quality over 7 days of cold storage. © 2019 Society of Chemical Industry.

Production of sesame oil oleogels based on beeswax and application as partial substitutes of animal fat in beef burger.

The effect of beeswax (BW) concentration (5, 7.5, 10%) and cooling temperature (4, 25 °C) on the properties of sesame oil oleogel was evaluated and compared with the extracted fats from beef flank and shank. Acid and peroxide values, fatty acid composition, color, texture, thermal properties and crystal morphology were studied. Then, 0, 25 and 50% of animal fat in beef burger were replaced by the oleogel (10% BW, cooled at 4 °C). Proximate composition, texture, color, fat absorption, cooking loss, shrinkage, microstructure, oxidative stability and sensory acceptance were determined for the burgers. Results indicated that acid value and thermal properties of the oleogels were affected by the BW concentration; however, peroxide value and fatty acid profile of the oleogels did not change as a function of the variables. The oleogels had less hardness than the animal fats which in turn decreased the hardness, gumminess and chewiness of the raw burgers to <50% of control sample. This is while cooked burger color did not significantly change. The 11% reduction of cooking loss and 1.6% reduction of fat absorption was considered as pros aspects of the oleogel incorporation to beef burger. However, cooking shrinkage and lipid oxidation increased significantly.

Investigation of stability, consistency, and oil oxidation of emulsion filled gel prepared by inulin and rice bran oil using ultrasonic radiation.

Inulin, rice bran oil and rosemary essential oil were used to produce high quality emulsion filled gel (EFG) using ultrasonic radiation. Response surface methodology was used to investigate the effects of oil content, inulin content and power of ultrasound on the stability and consistency of prepared EFG. The process conditions were optimized by conducting experiments at five different levels. Second order polynomial response surface equations were developed indicating the effect of variables on EFG stability and consistency. The oil content of 18%; inulin content of 44.6%; and power of ultrasound of 256 W were found to be the optimum conditions to achieve the best EFG stability and consistency. Microstructure and rheological properties of prepared EFG were investigated. Oil oxidation as a result of using ultrasonic radiation was also investigated. The increase of oxidation products and the decrease of total phenolic compounds as well as radical scavenging activity of antioxidant compounds showed the damaging effect of ultrasound on the oil quality of EFG.

Chemical stability of rainbow trout in icing medium containing pistachio (Pistachia vera) green hull extract during chilled storage.

In this study, the effect of icing medium containing different concentration of pistachio (Pistacia vera L. cv. Akbari) green hull extract (PHE) was investigated on the chemical stability of rainbow trout. The fishes were stored for 12 days in flaked ice containing 0, 0.1, 0.2 and 0.3% PHE and the parameters of pH, total volatile base nitrogen (TVB-N), histamine, free fatty acids, peroxide and thiobarbituric acid index (TBA-i) were periodically evaluated. In all experiments, a significant difference was evident between control and fish muscles stored in ice containing PHE. Fish icing with 0.3% PHE could considerably retard the oxidative and hydrolytic rancidity. In addition, it had significant effect on prevention of pH increase and production of volatile basic nitrogen during 12 days storage. PHE could diminish histamine accumulation in fish muscle and improve safety of rainbow trout. Consequently, PHE could have potential of application in icing medium for preservation of fish quality especially fatty ones.

Application of ultrasound treatment for improving the physicochemical, functional and rheological properties of myofibrillar proteins.

The aim of this study was to evaluate the impact of duration (10, 20 and 30min) and power (100 and 300W) of high-intensity ultrasound (20kHz) on physicochemical properties of beef myofibrillar proteins in order to investigate novel process for modification of its functional characteristics. Results showed that augmentation of duration and power of ultrasound led to enhance pH. Also, the water holding capacity and gel strength were improved by increasing pH. The highest value in pH, reactive sulfhydryl content, water holding capacity and gel strength was obtained in sample subjected to 30min of ultrasound at 300W. The particle size distribution of the proteins was decreased after ultrasound treatment because of the cavitation force of ultrasound waves. In this circumstance, an improvement of emulsifying properties can be obtained. Ultrasonic waves had significant effects on the rheological properties of myofibrillar proteins. Treated samples were more elastic and stiffer than control, although the inverse trend was observed after 30min treatment at each power. Finally, a reducing trend in viscosity was observed by increasing time and power of sonication. Ultrasonic treatment could successfully improve functional properties with effect on physicochemical properties of myofibrillar proteins.

Gluten-free products in celiac disease: Nutritional and technological challenges and solutions.

In celiac patient exposure to even only a small amount of gluten can lead to malabsorption of some important nutrients including calcium, iron, folic acid, and fat-soluble vitamins because of small-intestine inflammation. A strictly followed gluten-free (GF) diet throughout the patient's lifetime is the only effective treatment for celiac disease; however, elimination of gluten from cereal-based product leads to many technological and nutritional problems. This report discusses different substitutes to replace gluten functionality and examines the economic and social impacts of adherence to a GF diet. Better knowledge about the molecular basis of this disorder has encouraged the search for new methods of patient treatment. The new and common GF sources and different challenges encountered in production and consumption of these products and different solutions for improving their properties are discussed in this review.

The effects of Aloe vera (Aloe barbadensis) coating on the quality of shrimp during cold storage.

Green tiger shrimp (Penaeus semisulcatus) is an important aquaculture species worldwide. Its perishable nature, however, needs preservation methods to ensure its quality and shelf life. In this study, the effects of Aloe vera coating on the quality and shelf life of shrimps during cold storage were investigated. Shrimp samples were dipped in aqueous solutions containing 25%, 50%, 75%, and 100% Aloe vera gel before storage at 4 °C for 7 days. Drip loss, pH, TBA, TVB-N, and texture of both the control and treated shrimp samples were analyzed periodically. There were significant differences between coated shrimps and the control group in all parameters evaluated. Aloe vera at 75% and 100% concentrations was able to prevent lipid oxidation and drip loss properly; however, coatings containing 25% Aloe vera did not have the desired effects on these characteristics. Shrimps coated with higher concentrations of Aloe vera had better textural properties during cold storage. Results also indicated the positive effects of Aloe vera coating on the sensory quality of shrimp.

Qualitative improvement of low meat beef burger using Aloe vera.

Low meat beef burgers have found their niche in the food markets in developing countries because of their lower price. However, these burgers still lack an acceptable quality. This study investigates the effects of different concentrations of Aloe vera on the quality of this food product. For this purpose, beef burgers were produced with 0%, 1%, 3%, and 5% Aloe vera and the changes in their cooking parameters, lipid oxidation, texture, and appeal to consumers over 7days of refrigerated storage were evaluated. Results indicate that Aloe vera contributed to some extent to decreased cooking loss and diameter reduction in the burgers. Increased concentrations of Aloe vera led to improvements in the water absorption and texture of the burgers as well as their lipid stability. However, a concentration level of 3% led to the most acceptability of the product to the panelists. Finally, it was found that Aloe vera acts as a hydrocolloid and improves the quality of burgers.

Nanomechanical characteristics of meat and its constituents postmortem: a review.

Tenderness/toughness are two important factors in meat evaluation and can be well explained by their mechanical and nanomechanical characteristics, which in turn are highly affected by the complex arrangement of meat numerous constituents and the influence of endogenous enzymes on this biological structure. It has been also revealed that post-slaughter variations in muscle characters that make muscle to transform to meat are a consequence of changes in the nanomechanical properties of myofibrillar proteins through linkage with each other or even through their breakdown. However, background toughness that is related to the connective tissues exists just at the time of slaughter and does not change over the time. The most famous instruments that measure the mechanical characters of myofibrils in pico/nano scale are atomic force microscopy, also known as scanning force microscope, optical tweezer, and glass microneedle. In this regard, mechanical terms such as torsional strength, rotational Brownian motion, elastic modulus, viscoelasticity, flexibility, etc. are generally used to show different behavior of meat ultrastructure and the changes that usually occur in postmortem muscle. It is expected that the evaluation of nanomechanical properties of muscle cells and connective tissues, particularly when the muscle undergoes different changes, be useful in order to justify many features of meat postmortem.

Strategies Used in Production of Phenylalanine-Free Foods for PKU Management.

Phenylketonuria (PKU) is one of the most widespread dysfunctions caused by an inheritable problem in the phenylalanine metabolism. In this metabolic disease, gene mutations in phenylalanine hydroxylase (PAH) result in phenylalanine accumulation that causes varying degrees of mental retardation. The most effective treatment is restriction of phenylalanine in diet provided through different strategies including combination of low-protein foods, hydrolyzing of protein-rich foods, or use of protein substitutes. Meat and meat products, sea foods, milk and infant formula, cereal products, and beans are among the modified foods for PKU management. Elimination of phenylalanine from food presents major technological, nutritional, and organolleptic challenges because protein, as an essential structure-building and nutritional element, is removed. In addition, following this program is laborious, boring, and restrictive for both patients and their families. This paper reviews the current findings about PKU and the recent developments in the production of phenylalanine-free foods. Also, the nutritional requirements and challenges encountered by PKU individuals and food technologists are finally discussed.

A new, simple method for the production of meat-curing pigment under optimised conditions using response surface methodology.

The production of cured meat pigment using nitrite and ascorbate in acidic conditions was evaluated. HCl, ascorbate and nitrite concentrations were optimised at three levels using the response surface method (RSM). The effects of process variables on the nitrosoheme yield, the wavelength of maximum absorbance (λ(max)), and L*, a* and b* values were evaluated. The response surface equations indicate that variables exerted a significant effect on all dependent factors. The optimum combinations for the reaction were HCl=-0.8, ascorbate=0.46 and nitrite=1.00 as coded values for conversion of 1mM hemin to nitrosoheme, by which a pigment yield of 100%, which was similar to the predicted value of 99.5%, was obtained. Likewise, the other parameters were not significantly different from predicted values as the λ(max), L*, a* and b* values were 558 nm, 47.03, 45.17 and 17.20, respectively. The structure of the pigment was identified using FTIR and ESI/MS.

Role of globin moiety in the chemical structure of curing pigment.

In this study, the role of the globin moiety in the structure of this pigment has been evaluated, using myoglobin and hemin as model systems. After the synthesis of the cured pigment from the compounds used in this study, the absorption spectra, Fourier transform infrared spectroscopy (FTIR), and electrospray ionization (ESI)/MS spectroscopy were used to evaluate the chemical structure. Results indicated that the UV/visible, IR absorption, and mass spectroscopy of the cured pigment produced from myoglobin and its counterpart without the globin moiety, hemin, are different. Whereas myoglobin produced mononitrosylheme, hemin converted to dinitrosylheme, but probably the second nitric oxide group attached to the propionate side chain of the heme ring. It seems that the globin moiety protected heme ring against the second nitric oxide group.

Camel cocktail sausage and its physicochemical and sensory quality.

The objective of this study was to compare the nutritional values of camel semitendinosus muscles with those of calves. Then, sausages were made from camel meat, beef and equal proportions of each and stored at 4 degrees C for 45 days. The composition, physicochemical characteristics, sensory properties, and microstructure of the samples were evaluated. The proximate composition of meat from the two species was significantly different. Beef contained a significantly higher amount of vitamin E, whereas camel meat had better profile of fatty acid and higher iron content. Camel meat had a higher pH but similar myofibrillar protein content as beef. Sausages made from 100% camel meat also had higher pH and cooking yield along with higher a* (redness) and lower L* (lightness) than the others. 2-Thiobarbitoric acid values among these treatments were significantly different. Samples containing 50% of each meat had a higher resistance to shear force; however, panelists could not detect any significant difference in tenderness of the samples.

Comparison of fresh beef and camel meat proteolysis during cold storage.

The objective of this research was to determine the difference in myofibrillar fragmentation of camel meat and beef during postmortem aging. Semitendinosus muscle was excised at slaughter and muscle pH was measured at 6, 12, 24, 48, and 72h postmortem. Myofibril fragmentation index was measured on 1, 3, 5, and 7 days postmortem. Also, myofibrils isolated from semitendinosus muscles of camel and cattle at 1, 3, 5 and 7 days postmortem storage were analyzed using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Results showed that the camel semitendinosus muscle had significantly higher myofibril degradation values compared to that in beef which was supported by a difference in troponin-T degradation and appearance of a 30kDa band. Postmortem pH decline of camel meat was significantly slower than that of beef. This study demonstrated that the semitendinosus protease activity of camel meat was superior to that of beef, which may have been due to the difference in pH decline.