Peanut and linseed oil emulsion gels as potential fat replacer in emulsified sausages

Influence of beeswax-based fish oil oleogels on the mechanism of water and oil retention in Pacific white shrimp (Litopenaeus vannamei) meat emulsion gels: Filling, emulsification and phase transition

Oleogels have been used in the gelled surimi products to replace animal fats due to its structure characteristics. The effect of structure characteristics in fish oil oleogels on the mechanism of oil/water retention was investigated in meat emulsions. Beeswax assembly improved the oil and water retention. The unsaturation degree of fatty acids lowered the mobility of bound water, immobilized water as well as bound fat in the fish oil oleogel, but enhanced the mobility of free water and protons of unsaturated fatty acids. Beeswax addition and oil phase characteristics could enhance β-sheets, disulfide bonds and hydrophobic force to improve the viscoelasticity, gel strength and oil/water retention. Beeswax assembly facilitated the tight micro-sol network and filling effect, and high unsaturation degree promoted the emulsification effect, thus reducing phase transition temperature and juice loss. The study could lay the foundation for development of gelled shrimp meat products with EPA and DHA.

Pea protein/carboxymethyl cellulose complexes prepared using a pH cycle strategy as stabilizers of high internal phase emulsions for 3D printing

The development of food-grade high internal phase emulsions (HIPEs) for 3D printing and the replacement of animal fats have attracted considerable attention. In this study, in order to improve the rheological properties and stability of pea protein to prepare HIPE, pea protein/carboxymethyl cellulose (pH-PP/CMC) was prepared and subjected to pH cycle treatment to produce HIPEs. The results showed that pH cycle treatment and CMC significantly reduced the droplet size of HIPEs (from 143.33 to 12.10 μm). At higher CMC concentrations, the interfacial tension of the PP solution decreased from 12.84 to 11.71 mN/m without pH cycle treatment and to 10.79 mN/m with pH cycle treatment. The HIPEs with higher CMC concentrations subjected to pH cycle treatment showed shear thinning behavior and higher viscoelasticity and recovered their solid-like properties after being subjected to 50 % strain, indicating that they could be used for 3D printing. The 3D printing results showed that the pH-PP/CMC HIPE with 0.3 % CMC had the finest structure. Our work provides new insights into developing food-grade HIPEs and facilitating their use in 3D printing inks as nutrient delivery systems and animal fat substitutes.

Delivery of encapsulated bioactive compounds within food matrices to the digestive tract: recent trends and future perspectives

Encapsulation technologies have achieved encouraging results improving the stability, bioaccessibility and absorption of bioactive compounds post-consumption. There is a bulk of published research on the gastrointestinal behavior of encapsulated bioactive food materials alone using in vitro and in vivo digestion models, but an aspect often overlooked is the impact of the food structure, which is much more complex to unravel and still not well understood. This review focuses on discussing the recent findings in the application of encapsulated bioactive components in fabricated food matrices. Studies have suggested that the integration of encapsulated bioactive compounds has been proven to have an impact on the physicochemical characteristics of the finished product in addition to the protective effect of encapsulation on the fortified bioactive compound. These products containing bioactive compounds undergo further structural reorganization during digestion, impacting the release and emptying rates of fortified bioactive compounds. Thus, by manipulation of various food structures and matrices, the release and delivery of these bioactive compounds can be altered. This knowledge provides new opportunities for designing specialized foods for specific populations.

Strategies for Healthier Meat Foods: An Overview

Functional food products remain the focus of current market trends toward healthier nutrition. The consumption of meat-based functional foods has been a topic of interest in food innovation since some of these products generate controversy due to their possible adverse effects on health. However, studies have demonstrated that meat-based functional products are considered an opportunity to improve the nutritional profile of meat products through the addition of biologically valuable components and to meet the specific needs of consumers. In this sense, some strategies and techniques are applied for processing and developing functional meat products, such as modifying carcass composition through feeding, reformulating meat products, and processing conditions. This review focuses on presenting developed and evaluated strategies that allow the production of healthy and functional meat foods, which application has successfully achieved the sensory, nutritional, and technological parameters mainly affected by such application.

Effect of variation in basic emulsion structure and polysaccharide content on the physicochemical properties and structure of composite-based emulsion gels as cube fat mimetics

This study aimed to reveal the effect of different basic emulsion structures (W/O/W and O/W) and polysaccharide additions on protein-polysaccharide composite-based emulsion gels utilizing soybean protein isolate, palm oil and konjac glucomannan. The results of texture profile, rheological tests, microstructure observations, and oral tribology showed that basic emulsion structures and konjac glucomannan addition had significant effect on the emulsion gels' properties, while the impact of konjac glucomannan addition was stronger. W/O/W double emulsion gels (DEG) exhibited lower oral friction coefficients and obtained higher scores for oiliness and juiciness during the sensory evaluation. However, O/W single emulsion gels (SEG) displayed a firmer texture and higher chewiness, a 29.62% and 49.57% increase compared to the DEG at 7% konjac glucomannan addition on the hardness and chewiness respectively. It has demonstrated the emulsion gels' potential as cube fat mimetics and feasibility of adjusting their properties by changing the basic emulsion structure.

Evaluation of bigel systems as potential substitutes to partially replace pork backfat in semi-dry sausages

Bigels prepared with olive oil oleogels admixed with κ-carrageenan or κ-carrageenan and gelatin hydrogels (BG1 and BG2, respectively) were characterized with respect to microstructure and textural properties and were used as pork backfat alternatives in semi-dry sausages. Stable oleogel-in-hydrogel type bigels were formed, with BG2 having higher hardness values. Control sausages (CF) were formulated with 20% pork backfat and sausage treatments B1F and B2F had 50% of the pork backfat substituted by BG1 and BG2 bigels, respectively. Moisture, water activity, texture, microbial counts, sensorial and nutritional attributes of the resulting sausages were assessed during fermentation and after pasteurization and storage. Substituted sausages had increased weight loss, moisture, and water activity. Color evaluation revealed that the treatments with bigels exhibited the same trend in color formation and no differences were recorded in L* and a* values of the sausages. Total viable counts and lactic acid bacteria populations were not affected by the addition of bigel systems. Regarding the texture parameters, B2F semi-dry sausages exhibited similar values of hardness and cohesiveness to CF. Sausages formulated with bigels exhibited a reduction in energy (20%), fat (27%), saturated fatty acids (30%) and cholesterol (∼6%) content. B2F sausages had similar liking scores with CF, and they did not show any undesirable sensory attributes. The results demonstrate that bigels are a promising fat alternative to manufacture semi-dry meat products with lower fat content and a better nutritional profile.

Development of meat spread with omega-3 fatty acids derived from flaxseed oil for the elderly: Physicochemical, textural, and rheological properties

This study evaluates the characteristics of n-3-enriched meat spread that is in development for consumption by elderly individuals. Herein, flaxseed oil was used as a source of n-3 fatty acid, and macro- and nano-sized flaxseed oil emulsions (FOE) were prepared for the fabrication of meat spreads. As the level of FOE was increased in the meat spreads, significant increases in the levels of omega-3 fatty acids (α-linolenic acid) were observed. Emulsion stability and cooking loss were also improved in meat spreads formulated with FOE compared with those the control. In particular, the addition of FOE generated softer and less chewy meat, owing to its lower melting point and rheological properties. However, the high content of unsaturated fatty acids in the FOE-containing meat spreads increased their susceptibility to lipid oxidation meat. These findings indicate that FOE, particularly macro-sized FOE, has the potential for use in n-3 fatty acid enriched meat products that are intended for consumption by elderly individuals but need to be evaluated for their impacts on shelf-life and sensory quality.

Flaxseed Gum/Arabic Gum/Tween 80-Based Oleogel as a Fat Substitute Applied in Emulsified Sausage: Physicochemical Properties, Sensory Attributes and Nutritional Quality

In the present study, flaxseed gum (FG), Arabic gum (GA) and Tween 80 were used to prepare oleogels through an emulsion-templated method, and the obtained oleogels were designed for the partial substitution of pork fat in emulsified sausage. An increment in FG concentrations enhanced the viscoelasticity of emulsions, which resulted in the improved stability of emulsion systems, with smaller droplet sizes. In addition, increased FG concentrations contributed to higher mechanical strength, denser network structure and lower oil loss of oleogels. As a fat substitute, the prepared oleogels improved the textural properties and nutritional quality of emulsified sausages. With the increase in the substitution level of oleogels, the hardness and chewiness of the emulsified sausage increased, and the cooking loss decreased. Meanwhile, the reformulation with oleogels decreased the saturated fat from 57.04 g/100 g lipid to 12.05 g/100 g lipid, while increasing the ratio of omega-6 to omega-3 essential fatty acids from 0.10 to 0.39. The obtained results demonstrated that the flaxseed gum/Arabic gum/Tween 80-based oleogels had huge potential to successfully replace pork fat in emulsified sausage products.

Improved antioxidant properties of pork patties by replacing fat with resveratrol-loaded MP-CS complex stabilized pickering emulsion

The characterization and antioxidant ability of Res-loaded MP-CS stabilized Pickering emulsion, and its effects of fat reduction (25%, 50%, 75%, and 100%) in meat patties on pH, color, texture, cooking yield and antioxidant activity were investigated. Fat substitute using emulsion had no significant effect on pH and cooking yield. The addition of emulsion increased L* value and reduced a* value. a* value of meat patties with resveratrol added were higher than those without resveratrol group. Hardness and chewiness of meat patties with 25% and 100% fat replacement was lower than 50% and 75% fat replacement. The addition of emulsion could improve the network structure of meat patties and enhance oxidative stability. Oxidative stability of meat patties was improved by Res-loaded MP-CS stabilized Pickering emulsion. The results showed that MP-CS stabilized Pickering emulsion had great potential to be used as fat substitute for developing low-fat meat products, and the addition of resveratrol can improve the antioxidant ability of substitute fat meat products.

Plant-based meat analogs and fat substitutes, structuring technology and protein digestion: A review

There is currently an increasing trend in the consumption of meat analogs and fat substitutes due to the health hazards by excessive consumption of meat. Simulating the texture and mouthfeel of meat through structured plant-derived polymers has become a popular processing method. In this review, the mechanical structuring technology of plant polymers for completely replacing real meat is mainly introduced in this review, which mainly focuses on the parameters and principles of mechanical equipment for the production of vegan meat. The difference in composition between plant meat and real meat is mainly reflected in the protein, and particular attention should be paid to the digestive characteristics of plant meat protein in the gastrointestinal tract. Therefore, the differences in the protein digestibility properties of meat analogs and real meat is discussed in this review, focusing primarily on protein digestibility and peptide/amino acid composition of mechanically structured vegan meats. In terms of fat substitutes for meat products, the types of plant polymer colloidal systems used for meat fat substitutes is comprehensively introduced, including emulsion, hydrogel and oleogel.

Physicochemical properties and in vitro digestion behavior of emulsion gels stabilized by rice bran protein aggregates: Effects of heating time and induction methods

To investigate the effects of heating time and induction methods on the physicochemical properties and in vitro digestion behavior of emulsion gels, rice bran protein aggregates (RBPAs) were formed by acid-heat induction (90 °C, pH 2.0) and the emulsion gels were further prepared by adding GDL or/and laccase for single/double cross-linked induction. Heating time affected the aggregation and oil/water interfacial adsorption behavior of RBPAs. Suitable heating (1-6 h) was conducive to faster and more adsorption of aggregates at the oil/water interface. While excessive heating (7-10 h) resulted in protein precipitation, which inhibited the adsorption at the oil/water interface. The heating time at 2, 4, 5 and 6 h was thus chosen to prepare the subsequent emulsion gels. Compared with the single cross-linked emulsion gels, the double-cross-linked emulsion gels showed higher water holding capacity (WHC). After simulated gastrointestinal digestion, the single/double cross-linked emulsion gels all exhibited slow-release effect on free fatty acid (FFA). Moreover, the WHC and final FFA release rate of emulsion gels were closely related to the surface hydrophobicity, molecular flexibility, sulfhydryl, disulfide bond and interface behavior of RBPAs. Generally, these findings proved the potential of emulsion gels in designing fat alternatives, which could provide a novel technique for the fabrication of low-fat food.

Quality Characteristics of Reduced-Fat Emulsified Sausages Made with Yeast Mannoprotein Enzymatically Prepared with a β-1,6-glucanase

Mannoproteins, as yeast polysaccharides, have been utilized in food the industry as dietary fibers, emulsifying agents or fat replacers. Mannoprotein MP112, produced from yeast by enzymatic hydrolysis of myxobacterial β-1,6-glucanase GluM, exhibits excellent emulsifying properties in emulsion preparation. In this study, we aimed to examine the application of stable emulsion with the addition of mannoprotein MP112 (MP112 emulsion) to reduce the fat content of sausages. The addition of MP112 emulsion in emulsified sausages significantly reduced the fat content and increased the moisture and protein contents of emulsified sausages without the expense of their good sensory quality. Moreover, the textural properties of sausages were markedly improved with the higher hardness, chewiness and cohesiveness, especially in the 50-75% replacement ratio of MP112 emulsion. On the other hand, MP112 emulsion replacement of animal fat markedly improved the nutritional composition of emulsified sausages; they displayed a higher PUFA/SFA ratio and lower n-6/n-3 ratio due to their saturated fatty acids being replaced by poly-unsaturated fatty acids. Meanwhile, the oxidative stability of sausages was improved linearly, corresponding to the increased replacement ratio of MP112 emulsion. Our results show that mannoprotein-based emulsions could be used as potential fat alternatives in developing reduced-fat meat products.

Replacing Animal Fat with Gels of Psyllium Fiber and Combined Linseed Oil-Psyllium Fiber in Salamis: Impacts on Technological, Nutritional, Oxidative, and Sensory Properties

This study produced two gels: one solely using psyllium fiber (GP) and another combining this fiber with linseed oil (GL+P). Both gels replaced 15% and 30% of the animal fat content of salamis. The objective was to evaluate the impact of this lipid reformulation on the technological, nutritional, oxidative, and sensory properties of the salamis. The lipid reformulation did not alter the evolution of pH and lactic acid bacteria during processing. The addition of GL+P did not interfere with the product's drying process. However, replacing 30% of animal fat with the GP resulted in greater weight loss and a lower final Aw value. The lipid reformulation minimally affected the color of the salamis but significantly enhanced their nutritional profile. This improvement was marked by a decrease in fat content and an increase in protein. Specifically, in the samples with GL+P, there was a rise in linolenic acid content and a reduction in the n-6/n-3 PUFA ratio. Adding GP did not affect the salamis' oxidative stability and sensory profile. However, substituting 30% of the animal fat with GL+P increased the TBARS values, and volatile compounds derived from lipid oxidation hampered the products' sensory profiles. A reduction in these negative effects was observed when replacing 15% of the fat with GL+P, suggesting this to be the ideal dosage for balancing the nutritional benefits with maintaining the product's oxidative stability.

Effect of oil-modified crosslinked starch as a new fat replacer on gel properties, water distribution, and microstructures of pork meat batter

This work investigated the effects of oil-modified crosslinked starch (Oil-CTS) as a fat replacer on the gel properties, water distribution, microstructures, and fatty acid composition of pork meat batter. Results showed that the replacement of pork back fat by Oil-CTS could improve the gel performance in terms of rheological property, texture, and water-holding capacity (WHC), and reduce the water mobility of pork meat gels, which caused by the formation of a more ordered and denser protein network structure. Additionally, when the fat was replaced by Oil-CTS partially or totally (25-100 %), the total fat content in pork meat gels decreased by 16.5-82 % and the saturated fatty acids (SFAs) content decreased from 5.87 g/100 g in untreated sample to 1.17-4.88 g/100 g in starch-replacing-fat samples, indicating Oil-CTS could be used as a fat replacer to prepare the low-fat meat products.

Effect of vegetable oil hydrogel emulsion as a fat substitute on the physicochemical properties, fatty acid profile, and color stability of modified atmospheric packaged buffalo burgers

Buffalo burgers were prepared with 50% or 100% buffalo backfat substitution using walnut, and peanut oil emulsion gels (EGs) blended with chia flour. Burgers were stored at 2 °C in modified atmosphere packaging for 12 days. The fat replacement decreased total fat by 26% and increased ash by 34%. Hardness and chewiness decreased with increasing the fat replacement; however, it did not affect springiness and cohesiveness values. Burger reformulations led to an increase in cooking yield (10%). Walnut oil EGs increased PUFA level up to 458%. Both oils enhanced PUFA/SFA and ω-6/ω-3 ratios and atherogenic and thrombogenic indices. Concerning color attribute, about 66% reduction was observed in redness values during the storage period of 12 days. Moreover, the sensory scores for all attributes, i.e., appearance, odor, flavor, and juiciness, were in the acceptable range of five or above in the reformulated burgers. In conclusion, 50% fat substitution using walnut and peanut oil EGs improved the nutritional profile of buffalo burgers without compromising the technological and sensory characteristics.

Healthier Oils: A New Scope in the Development of Functional Meat and Dairy Products: A Review

In the present day, it has been widely established that a high intake of animal fat that contains a high content of saturated fatty acids may cause several life-threatening diseases, including obesity, diabetes-type 2, cardiovascular diseases, as well as several types of cancer. In this context, a great number of health organizations and government agencies have launched campaigns to reduce the saturated fat content in foods, which has prompted the food industry, which is no stranger to this problem, to start working to develop foods with a lower fat content or with a different fatty acid profile. Nevertheless, this is not an easy task due to the fact that saturated fat plays a very important role in food processing and in the sensorial perception of foods. Actually, the best way to replace saturated fat is with the use of structured vegetable or marine oils. The main strategies for structuring oils include pre-emulsification, microencapsulation, the development of gelled emulsions, and the development of oleogels. This review will examine the current literature on the different (i) healthier oils and (ii) strategies that will be potentially used by the food industry to reduce or replace the fat content in several food products.

Quality characteristics and gastrointestinal fate of low fat emulsified sausage formulated with konjac glucomannan/oat β-glucan composite hydrogel

The objective of present study was to evaluate the utilization of konjac glucomannan/oat β-glucan composite hydrogel as partial or complete fat replacer on the quality characteristics and gastrointestinal fate of emulsified sausages. The obtained results indicated that in comparison to control emulsified sausage sample, the incorporation of composite hydrogel at a 75 % fat replacement level could not only enhance emulsion stability, water holding capacity (WHC), and compact structure of formulated emulsified sausage, but also decrease their total fat content, cooking loss, hardness, and chewiness. The in vitro digestion results suggested the addition of konjac glucomannan/oat β-glucan composite hydrogel reduced the protein digestibility of emulsified sausage, while it did not change the molecular weight of digestive products. The confocal laser scanning microscopy(CLSM) image showed the addition of composite hydrogel changed the size of fat and protein aggregate of emulsified sausage during digestion. Based on these findings, the fabrication of composite hydrogel containing konjac glucomannan and oat β-glucan was a promising strategy as fat replacer. Furthermore, this study provided a theoretic basis for designing composite hydrogel based fat replacers.

Effects of pre-emulsified safflower oil with magnetic field modified soy 11S globulin on the gel, rheological, and sensory properties of reduced-animal fat pork batter

In this work, the differences in macrostructure and microstructure, rheology, and storage stability of pre-emulsified safflower oil (PSO) prepared by natural and magnetic field modified soy 11S globulin were analysised. It was concluded that the PSO with magnetic field modified soy 11S globulin (MPSO) has better emulsifying activity and physical stability. The changes in gel quality, oxidational sensitivity, rheological, and sensory properties of pork batters with different substitute ratios (0%, 25%, 50%, 75%, and 100%) of pork back-fat by MPSO with magnetic field modified soy 11S globulin were studied. Compared to the sample without MPSO, pork batter with MPSO showed higher emulsion stability, apparent viscosity, L^⁎ value, springiness, cohesiveness, and expressible moisture, while lower a^⁎ value and cooking loss. Moreover, added MPSO could be more uniformly distributed into the meat matrix with smaller holes. With the increase in the replacement proportion of pork back-fat, the hardness, water- and fat-holding capacity, and P₂₁ of pork batter significantly decreased (P < 0.05). As revealed by sensory evaluation and TBARS, using MPSO to substitute for pork back-fat decreased the lipid oxidational sensitivity of pork batter, and without negative effects on the appearance, juiciness and overall acceptability. Overall, it is feasible to apply MPSO as a pork-fat replacer to produce reduced-animal fat pork batter with excellent gel and sensory properties.

Effects of chickpea protein-stabilized Pickering emulsion on the structure and gelling properties of hairtail fish myosin gel

The effects of different amount (0-12%) of chickpea protein-stabilized Pickering emulsion (CPE) on the gelling properties, intermolecular interactions, microstructure, and physicochemical stability of hairtail fish myosin gels were investigated. The myosin gel with 6%-9% CPE demonstrated significantly higher viscoelasticity, gel strength, hardness, water-holding capacity and whiteness, compared to the control (P < 0.05). In addition, Raman spectroscopy showed that CPE changed the microenvironment of the myosin, which promoted the changes in protein secondary structures, disulfide bond conformation and the local environments of the composite gels. The addition of 6%-9% CPE also enhanced the disulfide bond and hydrophobic interaction of myosin gels which induced more compact gel network structures. Furthermore, CPE improved the lipid oxidative stability and freeze-thaw stability of myosin gel. The results indicated that CPE could improve the gelling properties of myosin, making it a potential new additive and lipid substitute for the development of new emulsion gel products.

Effects of incorporating processed Acacia seed as an emulsifying agent on the quality attributes of beef sausage

In this study, partial or full replacement of 6% soy protein isolate (SPI) with 2, 4 and 6% roasted Acacia seed flour (ASRo) and Acacia seed protein concentrates (ASPC) in emulsified beef sausage were investigated. Emulsion stability and cooking loss were lower in samples formulated with ASPC at all levels and control samples compared to ASRo formulated samples. ASRo generated softer and less chewy sausages than ASPC. Cooked 2% ASPC sausages had similar L* and a* values as the control but with lower colour difference (ΔE) values that were similar to cooked 6% SPI sausages' values. An organized protein network structure was observed in the sausages formulated with ASPC at all levels and in the control samples. Therefore, ASPC, particularly at 2 and 4% inclusion, can be used as a functional ingredient to prepare emulsified beef sausages with good quality attributes.

A Pumpkin-Based Emulsion Gel as a Texture Improvement of Mixed Horsemeat Semi-Smoked Sausages

Semi-smoked sausages were made with 5%, 10%, 15%, 20%, and 25% replacement of horsemeat by emulsion gel made with offal broth (stomach, kidney, liver, heart, brain, and a miscellaneous trimmings of a horse), pumpkin flour, and egg yolk in a ratio of 5:4:1. The technological, nutritional, oxidative, and rheological (G′ and G″) properties were studied. Sausage water holding capacity (WHC) rose after being incorporated with pumpkin-based emulsion gel (PEG). There was a statistically significant (p < 0.01) improvement in sausage emulsion stability. Lipid oxidation in all samples, especially 5% and 15% addition of emulsion gel samples, was below the rancidity criterion, which is TBARS > 2.0−2.5 mg MDA/kg sample. This really is encouraging because unsaturated fatty acids, such as those found in horsemeat, are easily oxidized. Use of the emulsion gel did not noticeably alter the sausages’ pH. Using emulsion gel considerably reduced the cooking loss (p < 0.05) of sausages and significantly improved texture (p < 0.05). Partial replacement of mixed horsemeat with emulsion gel improved the physicochemical characteristics of semi-smoked sausages. The elasticity modulus (G′) showed that PEG15 (15% of emulsion gel) was the most resilient gel. The least powerful gels (p < 0.05) were PEG20 and PEG25. According to this study, adding a pumpkin-based emulsion gel to the meat matrix could improve the quality of the emulsified meat system and provide important data for related research and companies as strategies to market a healthier and more nutritious product with the necessary quality characteristics.

Gel-type emulsified muscle products: Mechanisms, affecting factors, and applications

The gel-type emulsified muscle products improve fatty acid composition, maintain the oxidative stability, and achieve a better sensory acceptability. This review emphasizes the stabilization mechanisms of these emulsified muscle products. In particular, factors associated with the stability of the emulsified muscle systems are outlined, including the processing conditions (pH and heating), lipids, and emulsifiers. Besides, some novel systems are further introduced, including the Pickering emulsions and organogels, due to their great potential in stabilizing emulsified gels. Moreover, the promising prospects of emulsion muscle products such as improved gel properties, oxidative stability, freeze-thaw stability, fat replacement, and nutraceutical encapsulation were elaborated. This review comprehensively illustrates the considerations on developing gel-type emulsified products and provides inspiration for the rational design of emulsified muscle formulations with both oxidatively stable and organoleptically acceptable performance.

Microencapsulated Healthy Oil Mixtures to Enhance the Quality of Foal Pâtés

This study aimed to evaluate the use of microencapsulated oil mixtures as partial animal fat replacers and their effects on the physicochemical, nutritional and sensory qualities of foal pâtés. Three different batches were manufactured: a control (CON) formulation, with foal dorsal subcutaneous fat (30 g/100 g), and treatments 1 and 2 (T1 and T2), with 50% of the animal fat replaced by microcapsules containing algal oil mixed with walnut oil (T1) or pistachio oil (T2). The reformulated samples presented significant (p < 0.001) diminutions of fat contents, which achieved reductions of 34.22% (“reduced fat content”) and 28.17% in the T1 and T2 samples, respectively, and the lipid reformulation did not affect (p > 0.05) the texture or lipid oxidation of the samples. Furthermore, both microencapsulated oil mixtures significantly (p < 0.001) reduced (11−15%) saturated fatty acid (SFA) concentrations and increased (p < 0.001) mono- (T2) and polyunsaturated (T1) fatty acid contents (8% and 68%, respectively), contributing to the obtainment of nutritional indices in line with health recommendations. Additionally, consumer acceptability did not display significant (p > 0.05) differences among samples. Hence, the outcomes indicated that the incorporation of these microencapsulated oil mixtures as partial animal fat replacers, especially the T1 mixture, represents a promising strategy to obtain healthier foal pâtés, without compromising consumer approval.

Main animal fat replacers for the manufacture of healthy processed meat products

The technological, sensory, and nutritional characteristics of meat products are directly related to their animal fat content. Adding animal fat to meat products significantly influences their sensory properties, such as color, taste, and aroma. In addition, the physicochemical properties of fat decisively contribute to the texture of meat products, playing a fundamental role in improving the properties of viscosity, creaminess, chewiness, cohesiveness, and hardness. However, meat products' high animal fat content makes them detrimental to a healthy diet. Therefore, reducing the fat content of meat products is an urgent need, but it is a challenge for researchers and the meat industry. The fat reduction in meat products without compromising the product's quality and with minor impacts on the production costs is not a simple task. Thus, strategies to reduce the fat content of meat products should be studied with caution. During the last decades, several fat replacers were tested, but among all of them, the use of flours and fibers, hydrocolloids, mushrooms, and some animal proteins (such as whey and collagen) presented promising results. Additionally, multiple strategies to gel oils of vegetable origin are also a current topic of study, and these have certain advantages such as their appearance (attempts to imitate animal fat), while also improving the nutritional profile of the lipid fraction of the products meat. However, each of these fat substitutes has both advantages and limitations in their use, which will be discussed in subsequent sections. Therefore, due to the growing interest in this issue, this review focuses on the main substitutes for animal fat used in the production of meat products, offering detailed and updated information on the latest discoveries and advances in this area.

Application of Emulsion Gels as Fat Substitutes in Meat Products

Although traditional meat products are highly popular with consumers, the high levels of unsaturated fatty acids and cholesterol present significant health concerns. However, simply using plant oil rich in unsaturated fatty acids to replace animal fat in meat products causes a decline in product quality, such as lower levels of juiciness and hardness. Therefore, it is necessary to develop a fat substitute that can ensure the sensory quality of the product while reducing its fat content. Consequently, using emulsion gels to produce structured oils or introducing functional ingredients has attracted substantial attention for replacing the fat in meat products. This paper delineated emulsion gels into protein, polysaccharide, and protein–polysaccharide compound according to the matrix. The preparation methods and the application of the three emulsion gels as fat substitutes in meat products were reviewed. Since it displayed a unique separation structure, the double emulsion was highly suitable for encapsulating bioactive substances, such as functional oils, flavor components, and functional factors, while it also exhibited significant potential for developing low-fat or functional healthy meat products. This paper summarized the studies involving the utilization of double emulsion and gelled double emulsion as fat replacement agents to provide a theoretical basis for related research and new insight into the development of low-fat meat products.

Engineering Emulsion Gels as Functional Colloids Emphasizing Food Applications: A Review

Gels are functional materials with well-defined structures (three-dimensional networks) assembled from the dispersed colloids, and capable of containing a large amount of water, oil, or air (by replacing the liquid within the gel pores), known as a hydrogel, oleogel, and aerogel, respectively. An emulsion gel is a gelled matrix filled with emulsion dispersion in which at least one phase, either continuous phase or dispersed phase forms spatial networks leading to the formation of a semisolid texture. Recently, the interest in the application of gels as functional colloids has attracted great attention in the food industry due to their tunable morphology and microstructure, promising physicochemical, mechanical, and functional properties, and superior stability, as well as controlled release, features for the encapsulated bioactive compounds. This article covers recent research progress on functional colloids (emulsion gels), including their fabrication, classification (protein-, polysaccharide-, and mixed emulsion gels), and properties specifically those related to the gel-body interactions (texture perception, digestion, and absorption), and industrial applications. The emerging applications, including encapsulation and controlled release, texture design and modification, fat replacement, and probiotics delivery are summarized. A summary of future perspectives to promote emulsion gels' use as functional colloids and delivery systems for scouting potential new applications in the food industry is also proposed. Emulsion gels are promising colloids being used to tailor breakdown behavior and sensory perception of food, as well as for the processing, transportation, and targeted release of food additives, functional ingredients, and bioactive substances with flexibility in designing structural and functional parameters.

Effects of duck fat and κ-carrageenan as replacements for beef fat and pork backfat in frankfurters (R)

Objective

Frankfurters are emulsion-type sausages that are widely consumed worldwide. However, some concerns regarding negative health effects have been raised because of the high fat content and the type of fat. This study aimed to evaluate the effects of duck fat and κ-carrageenan as replacements for beef fat and pork backfat in frankfurters.

Methods

The different formulations for the frankfurters were as follows: 20% beef fat (BF), 20% pork backfat (PBF), 20% duck fat (DF), 20% soybean oil (SO), 20% duck fat/1% κ-carrageenan (DFC), and 20% soybean oil/1% κ-carrageenan (SOC). Physicochemical (fatty acid profile, color, rheological properties, cooking loss, water holding capacity, emulsion stability, and texture profile analysis), oxidative stability and sensory properties of frankfurters were evaluated.

Results

Duck fat and κ-carrageenan improved rheological properties of meat batter, and physicochemical properties (emulsion stability, cooking loss, and hardness) of frankfurters. Moreover, duck fat added-frankfurters (DF and DFC) had higher oxidative stability than that of soybean-added frankfurters (SO and SOC) during refrigerated storage for 28 days. In sensory evaluation, flavor, texture, and overall acceptability of DFC were acceptable to untrained panelists.

Conclusion

Our data suggest that duck fat and κ-carrageenan can replace beef fat and pork backfat in frankfurters. Duck fat and κ-carrageenan contributed to improve the physicochemical properties and oxidative stability while maintaining sensory properties. Therefore, the use of duck fat and κ-carrageenan may be a suitable alternative for replacing beef fat or pork backfat in frankfurters.

Cocoa Coproducts-Based and Walnut Oil Gelled Emulsion as Animal Fat Replacer and Healthy Bioactive Source in Beef Burgers

The aim of this work was to evaluate the effects on the chemical, physic-chemical, technological, and sensory properties of beef burger when replacing different quantities of fat (50 and 100%) with different levels of oil-in-water-gelled emulsion elaborated with walnut oil and cocoa bean shell flour (GECW). The chemical composition of the samples was affected by the fat replacement. The reformulation increased the moisture and ash content while the fat and protein content decreased with respect to the control sample. The linolenic and linolenic acid content of the beef burgers increased as the GECW replacement was augmented. The polyunsaturated fatty/saturated fatty acid ratio increased in both raw and cooked burgers, whereas the atherogenicity index and thrombogenicity index were reduced in both raw and cooked burgers with respect to the control sample. The use of GECW as a fat replacer was found to be effective in improving the cooking loss. Similarly, there were positive effects on reductions in the diameter and the increases in the thickness of the beef burgers. Regarding lipid stability, in both the raw and cooked burgers, the reformulation increased the 2-thiobarbituric acid reactive substance (TBARs) values with respect to the control sample. In both types of reformulated burgers, three bound polyphenols (mainly catechin and epicatechin) and two free polyphenols were identified, as were methylxanthines theobromine and caffeine. The sensory properties for the control and partial pork backfat replacement treatments were similar, while the sample with the total pork backfat replacement treatment showed the lowest scores. The blend of cocoa bean shell flour and walnut oil could be used as new ingredients for the development of beef burgers with a healthier nutritional profile without demeriting their sensory or cooking characteristics and physic-chemical properties.

Chemical, technological, instrumental, microstructural, oxidative and sensory properties of emulsified sausages formulated with microparticulated whey protein to substitute animal fat

The current study was conducted to investigate the utilization of microparticulated whey protein (MWP) in different levels (5% or 10%) as partial fat replacers in emulsified beef sausage formulations. Inclusion of MWP resulted in sausages having decreased amounts of fat and energy while increased amounts of protein. Both emulsion stability and processing yield were the highest in samples containing MWP. No differences were recorded in L* values of the sausages although both a* and b* values were higher in MWP sausages than in full-fat sausages regardless of MWP level. Increased amounts of MWP led to lower hardness, chewiness and adhesiveness. Micrographs brought out the organized and reticulated structure of the sausages containing 10% MWP. MWP did not cause unfavorable impacts in general sensory acceptance, besides, it was associated with increased oxidative stability. Overall, the findings highlighted the favorable effects of MWP in terms of nutritional, technological, sensory and oxidative quality indicating the possibility to design low-fat emulsified meat product formulations.

Influence of Murta (Ugni molinae Turcz) Powder on the Frankfurters Quality

Frankfurters are one of the most demanded meat products in the world due to their low cost and good taste. However, they contain up to 30% animal fat, which is negative for the consumer’s health. Moreover, high-fat contents could also decrease frankfurter sensory properties, since it accelerates the rancidity of the products. This fact is highly dependent on the fatty acids composition since the unsaturation promotes oxidative reactions. Currently, strategies have been developed to replace animal fat with vegetable oils or the inclusion of new raw materials. The murta (Ugni molinae Turcz), an endemic plant in Chile, is a specie that contains high levels of flavonoids in its fruits and has a pleasant flavor, as well as a sweet and floral aroma. However, the effect of the addition of these fruits in the formulation of meat products has been scarcely studied. The present study aims to reduce the use of synthetic additives using natural ones (murta powder). Therefore, this research evaluated the influence of the inclusion of murta on the chemical, sensory, and instrumental parameters of traditional frankfurters. Three batches of frankfurters were manufactured: control sausages without additives (T0); samples with chemical antioxidant (T1); and with murta fruit powder (T2). The chemical composition, physicochemical parameters and sensory properties were determined. Frankfurters made with murta (T2) presented middle values in energy, moisture and sodium compared with control. Also, the reformulated sausages (T2) presented the lowest water holding capacity, redness (a*) and yellowness and the highest values of fat and carbohydrates. Regarding fatty acids content, the most important changes were observed in the C18:0 and C14:0 (T2 presented the lowest values) and C18:2n-6 (T2 had the highest values), but minimal differences were observed in the total SFA, MUFA and PUFA content. Cholesterol content from T2 were similar to the control samples, and T1 presented the highest values. Although these differences, both chemical and nutritional quality of all frankfurters manufactured in the present study were very similar among treatments. Finally, according to the sensory analysis, T2 presented better acceptability and sensory characteristics compared with the other treatments (p ≤ 0.05). Therefore, the inclusion of murta in the production of frankfurters could be a strategy to improve the sensory characteristics of this product with minimal changes in chemical and nutritional properties. However, the effect of murta on oxidative stability and frankfurter shelf-life should be studied in depth in future research.

Use of Tremella as Fat Substitute for the Enhancement of Physicochemical and Sensory Profiles of Pork Sausage

Pork fat in sausage was replaced by tremella at different proportions during the process, and the physicochemical and sensory profiles of pork sausage were evaluated. Five recipes with the replacement proportion of 0%, 25%, 50%, 75%, and 100% tremella were manufactured, and their proximate compositions, water activities, textures, colors, water holding capacities (WHC), and amino acid compositions were investigated. The results showed that the protein, ash and moisture content, lightness, redness, and WHC of pork sausages were increased (p < 0.05), and textural profile analysis (TPA) and sensory quality of the sausage were improved (p < 0.05). In addition, the content of essential amino acids (lysine and isoleucine) and the non-essential amino acids (proline and tyrosine) of sausages were increased (p < 0.05). The sausage had the best sensory performance when the replacement ratio of tremella was 75%. These results indicated that replacing fat with tremella could be a valid way to obtain nutritional and healthy sausage.

Total and Partial Fat Replacement by Gelled Emulsion (Hemp Oil and Buckwheat Flour) and Its Impact on the Chemical, Technological and Sensory Properties of Frankfurters

A gelled emulsion (GE) prepared with hemp oil and buckwheat flour was used to replace pork back fat in frankfurters. Five different formulations were prepared: control (with 35% pork back fat—SC), and the following four to achieve 25%, 50%, 75%, and 100% pork back fat substitution by GE (S1, S2, S3, and S4, respectively). Nutritional, technological, and sensorial characteristics of frankfurters were evaluated. Sausages containing GE presented a lower total fat content with a higher amount of polyunsaturated fatty acids, increased omega 3 content, and reduced saturated fat by up to 55%. The incorporation of GE did not significantly modify technological properties such as emulsion stability or lipid oxidation in spite of using vegetable oils highly susceptible to oxidation. The reformulation of the frankfurters presented a greater effect on the texture and sensory properties when GE was used as total substitution for the pork back fat (S4). When GE was used only as partial substitution for the pork back fat, sausages similar to control frankfurter were obtained. So this study demonstrated that the use of GE could be a promising strategy in the reformulation of healthier meat products.