Characteristics, antimicrobial capacity, and antioxidant potential of electrospun zein/polyvinyl alcohol nanofibers containing thymoquinone and electrosprayed resveratrol nanoparticles.

The aim of the present study was to fabricate, characterize, and evaluate the in vitro antimicrobial and antioxidant properties of zein/polyvinyl alcohol (ZN/PVA) nanofibers containing 2% and 4% of thymoquinone (TQ), either alone or in combination with electrosprayed ZN nanoparticles containing 1% and 2% of resveratrol (RS). According to scanning electron microscopy analysis, the diameter of nanofibers and nanoparticles increased with increasing TQ and RS concentrations, respectively. The molecular interaction between ZN or PVA polymers and TQ or RS was confirmed by Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the thermal stability of nanofibers did not change with the addition of TQ and RS. Moreover, incorporation of TQ in nanofibers along with RS nanoparticles increased their antibacterial and free radical scavenging activities based on broth dilution and DPPH methods, respectively (p ≤ .05). Escherichia coli O157:H7 (as a Gram-negative pathogenic bacteria) was more resistant to all treatments than Staphylococcus aureus (as a Gram-positive pathogenic bacteria). In addition, the combined use of TQ in nanofibers and RS nanoparticles had antagonistic antibacterial and synergistic antioxidant effects. The best results were obtained with ZN/PVA nanofiber containing 4% TQ and electrosprayed with 2% RS nanoparticles (p ≤ .05). According to the results of the present study, biodegradable ZN/PVA nanofiber containing TQ and electrosprayed with RS nanoparticles can be used as a novel active packaging material in the food industry.

Impact of sodium alginate-based film loaded with resveratrol and thymol on the shelf life of cooked sausage and the inoculated Listeria monocytogenes.

In present study, sodium alginate biodegradable films containing different concentrations of resveratrol (RES: 0.002% and 0.004%) or thymol (THY: 0.5% and 1%) and their combinations were prepared, and evaluated for their effects on spoilage-related microbial profile, lipid oxidation, sensory properties, and protective effects against Listeria monocytogenes in beef mortadella sausage during 40 days storage at 4°C. The release rate of phenolic compounds was determined by the Folin-Ciocalteu test. To assess the shelf life of the product, changes in total viable count (TVC), lactic acid bacteria count (LAB), psychrotrophic bacteria count (PTC), pH levels, thiobarbituric acid reactive substances (TBARS) levels, and sensory characteristics (taste, color, odor, and overall acceptability) were evaluated. For the sensory evaluation, a panel of 70 semi-trained judges was selected according to their initial performance. Samples wrapped with sodium alginate films containing 1% THY (alone or combined with different concentrations of RES) exhibited lower bacterial counts compared to other experimental groups at the end of the storage period (6.01-6.35 vs. 6.71-8.17 log10 CFU/g for TVC, 5.37-5.83 vs. 6.07-7.11 log10 CFU/g for LAB, 5.08-5.18 vs. 5.40-7.23 log10 CFU/g for PTC, and 6.53-6.92 vs. 7.23-9.01 log10 CFU/g for inoculated L. monocytogenes). Sodium alginate films containing the combination of 0.004% RES and different concentrations of THY showed higher antioxidant effects than other experimental groups (TBARS values of 1.68-1.99 vs. 2.23-3.80 mg MDA/kg sample). The sodium alginate film containing 0.004% RES + 1% THY exhibited the highest antimicrobial and antioxidant activities and highest sensory scores among all treatments. These findings highlight the potential application of the sodium alginate film containing a combination of RES and THY as an active packaging material with natural preservatives in the meat products industry. This application can effectively extend the shelf life and enhance the microbial safety of clean-label cooked sausages during refrigerated storage.

A review of different frying oils and oleogels as alternative frying media for fat-uptake reduction in deep-fat fried foods.

Purpose: This review aims to examine the potential of oleogels as a frying medium to decrease oil absorption during deep-frying and enhance the nutritional and energy content of foods. By investigating the factors influencing oil incorporation during deep-frying and examining the application of oleogels in this process, we seek to provide insights into using oleogels as an alternative to traditional cooking oils. Scope: Deep-frying, a widely used cooking method, leads to the retention of large amounts of oil in fried food, which has been associated with health concerns. To address this issue, researchers have investigated various methods to minimize oil absorption during frying. One promising approach is the use of oleogels, which are thermo-reversible, three-dimensional gel networks formed by entrapment of bulk oil with a low concentration (<10% of weight) of solid lipid materials known as oleogelators. This review will focus on the following aspects: a) an overview of deep-fried foods, b) factors influencing oil uptake and underlying mechanisms for oil absorption during deep-frying, c) the characterization and application of different frying oils and their oleogels in deep-fried foods, d) components of the oleogel system for deep-frying, and e) the health impact, oxidative stability, and sensory acceptability of using oleogels in deep-frying. Key findings: The review highlights the potential of oleogels as a promising alternative frying medium to reduce fat absorption in deep-fried foods. Considering the factors influencing oil uptake during deep-frying, as well as exploring the properties and applications of different frying oils and their oleogels, can result in improved product qualities and heightened consumer acceptance. Moreover, oleogels offer the advantage of lower fat content in fried products, addressing health concerns associated with traditional deep-frying methods. The capacity to enhance the nutritional and energy profile of foods while preserving sensory qualities and oxidative stability positions oleogels as a promising choice for upcoming food processing applications.

The Prevalence and Determinants of Vitamin D Status among Older Adults: Data from a Longitudinal Aging Study.

Background: Aging is identified as a risk factor for vitamin D deficiency (VDD) therefore this investigation was designed to determine the prevalence of VDD and its determinants in a sample of older adults. Methods: The data of this study were obtained from the baseline wave of the Longitudinal Aging Study (LAS). Demographic, past medical history, medication history, and smoking behavior were collected using an interview approach. The physical activity and nutritional status of the participants were assessed using a standard questionnaire. Anthropometric indices were measured according to a standard protocol then body mass index (BMI) was calculated. Serum vitamin D and calcium levels were measured by autoanalyzers. Univariate and multiple logistic regression models were applied to detect the associated factors with VDD. Results: Mean age of the participants was 71.82 (SD = 7.63) years. A total of 1319 people participated in our study, and 51.16% (n = 688) were female. A total of 8.42% (n = 111) of the participants had VDD and 17.06% of them (n = 225) had insufficient vitamin D levels. In the multivariable logistic regression model, the age group of 70-79 years in comparison with the age group of 60-69 years had a 43% less chance of VDD. Furthermore, being overweight (OR = 0.36, P = 0.01) and obese (OR = 0.35, P = 0.02), and taking vitamin D supplements (OR = 0.31, P = 0.04) were significantly associated with VDD. Conclusions: Our results showed that 25% of older adults had vitamin D deficiency or insufficiency. In addition, some modifiable lifestyle factors were associated with VDD. Given that, old age is considered a risk factor for VDD. Therefore, detection and improvement of VDD may be a preventive measure in at-risk subjects.

Sous-vide processing of silver carp: Effect of processing temperature and cold storage duration on the microbial quality of the product as well as modeling by artificial neural networks.

Silver carp (Hypophthalmichthys molitrixi) was processed by sous-vide method at different temperatures (60, 65, 70, and 75°C). Then, the microbiological quality of the processed samples was monitored during cold storage (4°C) for 21 days. The target microorganisms were Enterobacteriaceae, Lactic Acid bacteria (LAB), Pseudomonas, Psychrotrophs, and total viable count (TVC). In samples processed at 75°C, the presence of Enterobacteriaceae, Pseudomonas and Psychrotrophs were not detectable up to 15 days of storage and lactic acid bacteria were not detectable even at the end of the storage period. A radial basis function neural network (RBFNN) model was established to predict the changes in the microbial content of silver carp. In this step, the relationship between processing temperature and storage duration on microbial growth was modeled by ANNs (artificial neural networks). The optimal ANN topology for modeling Enterobacteriaceae, Pseudomonas, and Psychrotroph contained 9 neurons in the hidden layer, but it contained 15 and 14 neurons for TVC and LAB, respectively. By experimenting with the temperature of -80°C, it was revealed that the obtained ANN model has a high potential for prediction.

Synthesis of spirulina loaded chitosan nanoparticles from prawn, Macrobrachium nipponense shell for extending the shelf life of pike-perch (Sander lucioperca) fillet during refrigerated storage.

BACKGROUND: This study was aimed to synthesize polymeric chitosan nanoparticles (CSNPs) from Macrobrachium nipponense shells using sodium triphosphate (TPP) as a crosslinker that was incorporated with spirulina extract (SPE) to improve the shelf life of pike-perch during refrigerated storage (4 °C). RESULTS: The encapsulation efficiency (EE) of SPE-loaded CSNPs decreased from 67% to 32%, and loading capacity (LC) was increased (10-14%) depending on their loaded SPE concentrations. The initial burst effect, followed by a slow-release at pH 7 (24 h), was observed. Free SPE and SPE incorporated CSNPs decreased microbial counts (total viable count, total psychotropic count, pseudomonas, and lactic acid bacteria) compared to control and unloaded CSNPs. Samples treated with free SPE or SPE-loaded CSNPs showed higher changes in odor, color, TVB-N (total volatile basic nitrogen), and TBA (thiobarbituric acid) compared with the unloaded CSNPs batch (P ≤ 0.05) until the tenth day of storage. However, fish fillets coated with SPE-loaded CSNPs had the highest overall consumer acceptability and the lowest values for TVB-N and TBA at the end of storage (14th  day). Controlled release of bioactive compounds in batches treated with SPE-CSNPs could delay the microbial degradation and enhance chemical reactions (TBA and TVB-N) in comparison to pure SPE during storage time. CONCLUSION: The incorporation of SPE in polymeric CSNPs can be considered as a promising material for controlled delivery of natural bioactive agents, and preservation of Pike perch quality during refrigerator storage. © 2022 Society of Chemical Industry.

Recent progress in using zein nanoparticles-loaded nanocomposites for food packaging applications.

Biopolymers are important due to their exceptional functional and barrier properties and also their non-toxicity and eco-friendly nature for various food, biomedical, and pharmaceutical applications. However, biopolymers usually need reinforcement strategies to address their poor mechanical, thermal, and physical properties as well as processability aspects. Several natural nanoparticles have been proposed as reinforcing agents for biopolymeric food packaging materials. Among them, zein nanoparticles (ZNPs) have attracted a lot of interest, being an environmentally friendly material. The purpose of the present review paper is to provide a comprehensive overview of the ZNPs-loaded nanocomposites for food packaging applications, starting from the synthesis, characteristics and properties of ZNPs, to the physicochemical properties of the ZNPs-loaded nanocomposites, in terms of morphology, permeability, solubility, optical features, hydrophobic/hydrophilic behavior, structural characteristics, thermal features, and mechanical attributes. Finally, at the end of this review, some considerations about the safety issues and gastrointestinal fate of ZNPs, as well as the use of ZNPs-based nanocomposites as food packaging, are reported, taking into account that, despite the enormous benefits, nanotechnology also presents some risks associated to the use of nanometric materials.

Migration of Various Nanoparticles into Food Samples: A Review.

Nanotechnology has provided new opportunities for the food industry with its applications in food packaging. The addition of nanoparticles, such as clay, silver and copper, can improve the mechanical and antimicrobial properties of food packaging. However, nanoparticles may have an adverse impact on human health. This has led to legislative and regulatory concerns. The inhibitory effects of nano packaging on different microorganisms, such as Salmonella, E. coli, and molds, have been studied. Nanoparticles, like other materials, may have a diverse set of properties that need to be determined. In this review, different features of silver, clay and copper nanoparticles, such as their anti-microbial, cell toxicity, genetic toxicity, mechanical properties, and migration, are critically evaluated in the case of food packaging. Specifically, the viewpoints of WHO, FDA, and ESFA, concerning the nano-silver application in food packaging, are discussed as well.

Physicochemical Changes of Deep-Fat-Fried Chicken Drumsticks Treated with Quercetin-in-Edible Coating during Storage Time.

In this study, 10% of chicken protein isolate (CPI) and quercetin (1 mg/mL) were used to develop an edible coating to improve the oxidative stability of deep-fat-fried chicken drumsticks during refrigerated storage (4 °C) for 10 days. Chicken samples with edible coating formulated with only 10% CPI served as the control. Although the thiobarbituric acid reactive substances (TBARS) values of the treated samples were lower than the control samples, no significant differences were observed. Quercetin-treated samples were generally harder than control samples. The pH was reduced by quercetin incorporation (p < 0.05). L* and b* values increased, while there was no significant variation in a* values during storage (p > 0.05).

A modified reinforced clostridial medium for the isolation and enumeration of Lactobacillus delbrueckii ssp. bulgaricus in a mixed culture.

In this study, we modified reinforced clostridial medium (RCM) to selectively enumerate and isolate Lactobacillus delbrueckii ssp. bulgaricus, a probiotic and important starter culture in the dairy industry. The disparity in the reported carbohydrate fermentation pattern of L. delbrueckii ssp. bulgaricus was used to develop a growth medium not only selective for L. delbrueckii ssp. bulgaricus but significantly inhibitory to the growth of other lactic acid bacteria. A recently modified RCM (mRCM) was optimized for this study by the addition of 0.5% fructose, 0.5% dextrose, 1% maltose, and 0.25% sodium pyruvate while replacing lactose as a carbohydrate source. The cell recovery and bacterial counts of L. delbrueckii ssp. bulgaricus in tested products (pure L. delbrueckii ssp. bulgaricus strains, starter culture, probiotic supplements, and yogurt) using our mRCM with sodium pyruvate (mRCM-PYR) were significantly higher than in the recently modified RCM and the common de Man, Rogosa, and Sharpe (MRS) culture medium. The growth of other lactic acid bacteria (Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Lactobacillus reuteri) and Bifidobacteria was retarded in this modified medium compared with their growth in MRS and mRCM. This result is a significant improvement in the enumeration and differentiation of L. delbrueckii ssp. bulgaricus in mRCM-PYR compared with the results in MRS and mRCM where the high background growth of similar species interferes with the accuracy of bacterial population counts. Our results thus suggest that mRCM-PYR could be recommended as a reliable alternative growth medium for the selective enumeration and isolation of L. delbrueckii ssp. bulgaricus in a mixed culture.

Egg quality and safety with an overview of edible coating application for egg preservation.

Eggs are staple food in the human diet and are consumed globally. They represent a complete food required for well-being and are recognized by consumers as versatile and wholesome with a balance of essential nutrients. However, eggs are perishable and susceptible to contamination with certain microorganisms. Past studies concluded that edible coatings have been successful to maintain the interior quality and reduce the microbial load on the eggshell surface. This paper provides an overview of the egg quality and safety and discusses the application of various types of lipid-, polysaccharide-, and protein-based edible coating systems on eggs. Edible coatings could be a viable alternative to existing techniques for maintaining the internal quality and safety of fresh eggs during long-term storage.

Application of a Surimi-Based Coating to Improve the Quality Attributes of Shrimp during Refrigerated Storage.

Shrimp is a popular seafood throughout the world. However, shrimp is highly perishable due to biochemical, microbiological, or physical changes during postmortem storage. In this study, the effect of a surimi-based coating with and without montmorillonite (MMT) nanoclay on shrimp quality was evaluated during eight days of refrigerator storage. Use of a surimi-based coating resulted in reductions of aerobic plate counts (APC) up to 2 log units. The combined effect of the MMT and coating was observed. Surimi-based coating with MMT resulted in lower APC (p < 0.05) toward the end of storage. The application of surimi-based coating with MMT to the shrimp samples improved sensory quality and delayed lipid oxidation and color deterioration during storage time. In general, better texture was observed when coating was applied either with or without MMT. This study suggests that surimi-based coating may improve the quality of shrimp during refrigerated storage.

Impact of Sweet Potato Starch-Based Nanocomposite Films Activated With Thyme Essential Oil on the Shelf-Life of Baby Spinach Leaves.

Salmonella Typhimurium (S. Typhi) and Escherichia coli (E. coli) have been responsible for an increasing number of outbreaks linked to fresh produce, such as baby spinach leaves, in the last two decades. More recently, antimicrobial biodegradable packaging systems have been attracting much attention in the food packaging industry as eco-friendly alternatives to conventional plastic packaging. The objective of this study was to evaluate the effect of antibacterial nanocomposite films on inoculated spinach leaves and on the sensory properties of these leaves during eight days of refrigerated storage. In this study, an antibacterial film comprised of sweet potato starch (SPS), montmorillonite (MMT) nanoclays and thyme essential oil (TEO) as a natural antimicrobial agent was developed. Our results showed that the incorporation of TEO in the film significantly (p < 0.05) reduced the population of E. coli and S. Typhi on fresh baby spinach leaves to below detectable levels within five days, whereas the control samples without essential oil maintained approximately 4.5 Log colony forming unit (CFU)/g. The sensory scores for spinach samples wrapped in films containing TEO were higher than those of the control. This study thus suggests that TEO has the potential to be directly incorporated into a SPS film to prepare antimicrobial nanocomposite films for food packaging applications.

Antibacterial and Antioxidant Activities of Essential Oils from Artemisia herba-alba Asso., Pelargonium capitatum × radens and Laurus nobilis L.

Essential oils are natural antimicrobials that have the potential to provide a safer alternative to synthetic antimicrobials currently used in the food industry. Therefore, the aim of this study was to evaluate the antimicrobial and antioxidant activities of essential oils from white wormwood, rose-scented geranium and bay laurel against Salmonella typhimurium and Escherichia coli O157:H7 on fresh produce and to examine consumer acceptability of fresh produce treated with these essential oils. Our results showed that essential oil derived from rose-scented geranium exhibited the most effective antimicrobial activity at the same and similar minimum inhibition concentration levels (0.4%, v/v and 0.4% and 0.5%, v/v) respectively against Salmonella typhimurium and Escherichia coli O157:H7. All three essential oils showed antioxidant properties, with the highest activity occurring in bay laurel essential oil. In a sensory test, tomatoes, cantaloupe and spinach sprayed with 0.4% rose-scented geranium essential oil received higher scores by panelists. In conclusion, rose-scented geranium essential oil could be developed into a natural antimicrobial to prevent contamination of Salmonella typhimurium and Escherichia coli O157:H7 in fresh produce, plus this oil would provide additional health benefits due to the antioxidant properties of its residue.

Physicochemical properties of surimi gels fortified with dietary fiber.

Although dietary fiber provides health benefits, most Western populations have insufficient intake. Surimi seafood is not currently fortified with dietary fiber, nor have the effects of fiber fortification on physicochemical properties of surimi been thoroughly studied. In the present study, Alaska pollock surimi was fortified with 0-8 g/100 g of long-chain powdered cellulose as a source of dietary fiber. The protein/water concentrations in surimi were kept constant by adding an inert filler, silicon dioxide in inverse concentrations to the fiber fortification. Fiber-fortified surimi gels were set at 90 °C. The objectives were to determine (1) textural and colour properties; (2) heat-induced gelation (dynamic rheology); and (3) protein endothermic transitions (differential scanning calorimetry) of surimi formulated with constant protein/water, but variable fiber content. Fiber fortification up to 6 g/100 g improved (P<0.05) texture and colour although some decline occurred with 8 g/100g of fiber. Dynamic rheology correlated with texture and showed large increase in gel elasticity, indicating enhanced thermal gelation of surimi. Differential scanning calorimetry showed that fiber fortification did not interfere with thermal transitions of surimi myosin and actin. Long-chain fiber probably traps water physically, which is stabilized by chemical bonding with protein within surimi gel matrix. Based on the present study, it is suggested that the fiber-protein interaction is mediated by water and is physicochemical in nature.

Interactions of dietary fibre and omega-3-rich oil with protein in surimi gels developed with salt substitute.

Most Western populations have insufficient intake of fibre and ω-3 polyunsaturated fatty acids (PUFAs), while sodium intake greatly exceeds the recommended maximum. Surimi seafood is not currently fortified with these nutraceutical ingredients. Alaska pollock surimi seafood was developed with salt substitute and fortified with either 6g/100g of fibre or 10 g/100g of ω-3 oil (flax:algae:menhaden, 8:1:1) or fibre+ω-3 oil (6g/100g of fibre+10 g/100g of ω-3 oil). The objective was to determine effects of the dietary fortification on physicochemical properties of surimi. Fortification with either dietary fibre or ω-3 oil alone or in combination enhanced (P<0.05) rheological and textural characteristics. The combined fortification had a synergistic effect on rheological properties. This indicates greater gelation of surimi in the presence of fibre+ω-3 oil, suggesting their interaction with surimi myofibrillar proteins. Fibre results in protein dehydration increasing protein concentration; while oil is immobilised by protein filling void spaces in the gel matrix. Differential scanning calorimetry showed that fibre and ω-3 oil did not interfere with normal denaturation of surimi proteins. Colour properties were only slightly affected (P<0.05). Fortification of surimi with fibre and ω-3 oil resulted in a quality product that could be useful in developing surimi products with nutritional benefits.

Chemical properties of ω-3 fortified gels made of protein isolate recovered with isoelectric solubilisation/precipitation from whole fish.

Protein isolate was recovered from whole gutted fish using isoelectric solubilisation/precipitation (ISP). The objective was to determine chemical properties of heat-set gels made of the ISP protein isolate fortified with ω-3 polyunsaturated fatty acids (PUFAs)-rich oils (flaxseed, fish, algae, krill, and blend). The extent of the PUFAs increase, ω-6/ω-3 FAs and unsaturated/saturated FAs ratios, and the indices of thrombogenicity and atherogenicity depended on specific ω-3 PUFAs-rich oil used to fortify protein isolate gels. Lipid oxidation in ω-3 PUFAs fortified gels was minimal, although greater (P<0.05) than control gels (without ω-3 PUFAs fortification). However, all gels were in the slightly rancid, but acceptable range. The commonly used thiobarbituric-acid-reactive-substances (TBARS) assay to determine lipid oxidation in seafood may be inaccurate for samples containing krill oil due to its red pigment, astaxanthin. Protein degradation (total-volatile-basic-nitrogen) was greater (P<0.05) in ω-3 PUFAs fortified gels than control gels. However, all gels were considerably below the acceptability threshold for protein degradation. The shear stress of ω-3 PUFAs fortified gels was generally greater than the control gels and the shear strain was generally unchanged. This study demonstrates that ω-3 PUFAs fortification of protein isolates recovered with ISP from fish processing by-products or whole fish has potential application in the development of functional foods.

Isoelectric solubilization/precipitation as a means to recover protein isolate from striped bass (Morone saxatilis) and its physicochemical properties in a nutraceutical seafood product.

Excessive dietary intake of Na (i.e., NaCl) contributes to hypertension, which is a major risk factor for cardiovascular disease. Normally, NaOH and HCl are used to dissolve and precipitate, respectively, fish muscle proteins in isoelectric solubilization/precipitation (ISP), therefore contributing to increased Na content in the recovered fish protein isolates (FPI). Substitution of NaOH with KOH may decrease the Na content in FPI and, thus, allow development of reduced-Na seafood products. In this study, FPI was recovered with ISP using NaOH or KOH. In order to develop a nutraceutical seafood product, the FPI was extracted with NaCl or KCl-based salt substitute and subjected to cold- or heat-gelation. In addition, standard nutraceutical additives (ω-3 fatty acids-rich oil and dietary fiber) along with titanium dioxide (TiO2) were added to FPI. Color, texture, dynamic rheology, Na and K content, and lipid oxidation of the FPI gels were compared to commercial Alaska pollock surimi gels. FPI gels had greater (p < 0.05) whiteness, good color properties (L*a*b*), and generally better textural properties when compared to surimi gels. Although the ISP-recovered FPI and surimi developed similar final gel elasticity, the proteins in FPI and surimi had different gelation pattern. A reduction (p < 0.05) of Na content and simultaneous increase (p < 0.05) in K content of FPI gels was achieved by the substitution of NaOH with KOH during ISP and NaCl with the KCl-based salt substitute during formulation of the FPI paste. Although cooking and addition of NaCl during formulation of the FPI paste increased (p < 0.05) lipid oxidation in FPI gels, TBARS values were much below rancidity levels. These results indicate that KOH can replace NaOH to recover FPI from whole gutted fish for subsequent development of nutraceutical seafood products tailored for reduction of diet-driven cardiovascular disease.

A three-prong strategy to develop functional food using protein isolates recovered from chicken processing by-products with isoelectric solubilization/precipitation.

BACKGROUND: Skin-on bone-in chicken drumsticks were processed with isoelectric solubilization/precipitation to recover muscle proteins. The drumsticks were used as a model for dark chicken meat processing by-products. The main objective of this study was conversion of dark chicken meat processing by-products to restructured functional food product. An attempt was made to develop functional food product that would resemble respective product made from boneless skinless chicken breast meat. A three-prong strategy to address diet-driven cardiovascular disease (CVD)with a functional food was used in this study. The strategy included addition of three ingredients with well-documented cardiovascular benefits: (i) ω-3 polyunsaturated fatty acid-rich oil (flaxseed-algae, 9:1); (ii) soluble fiber; and (iii) salt substitute. Titanium dioxide, potato starch, polyphosphate, and transglutaminase were also added. The batters were formulated and cooked resulting in heat-set gels. RESULTS: Color (L*a*b*), texture (torsion test, Kramer shear test, and texture profile analysis), thermal denaturation (differential scanning calorimetry), and gelation (dynamic rheology) of chicken drumstick gels and chicken breast gels were determined and compared. Chicken drumstick gels generally had comparable color and texture properties to the gels made from chicken breast meat. The endothermic transition (thermal denaturation) of myosin was more pronounced and gelation properties were better for the drumstick gels. CONCLUSION: This study demonstrated a feasibility to develop functional food made of muscle proteins recovered with isoelectric solubilization/precipitation from low-value dark chicken meat processing by-products. The functional food developed in this study was enriched with CVD-beneficial nutrients and had comparable instrumental quality attributes to respective products made of chicken breast meat. Although the results of this study point towards the potential for a novel, marketable functional food product, sensory tests and storage stability study are recommended.

Physicochemical changes in surimi with salt substitute.

Protein endothermic transitions (thermal denaturation), rheological properties (protein gelation), and fundamental texture properties (shear stress and strain at mechanical fracture) of Alaska pollock surimi gels made with 0 (control), 1, 2, and 3g/100g of salt (NaCl) were determined and compared with equal molar concentration of salt substitute. Salt and salt substitute shifted the onset of myosin transition to higher temperature and resulted in larger myosin peaks (i.e., transition enthalpy). Endothermic transitions showed similar trends to rheological properties. The elastic modulus (G') increased when salt or salt substitute was added to surimi, except at the highest concentration of salt and salt substitute. Salt and salt substitute also induced the onset of protein gelation (i.e., as measured by significant increase of G') at lower temperature. Surimi gels with salt substitute and salt at equal molar concentrations had similar texture properties (shear stress and strain). Based on the present study, salt substitute can be used in the development of low-sodium surimi seafood products without significant change in gelation and texture.