Advancements in Sustainable Plant-Based Alternatives: Exploring Proteins, Fats, and Manufacturing Challenges in Alternative Meat Production

The rise in plant-based food consumption is propelled by concerns for sustainability, personal beliefs, and a focus on healthy dietary habits. This trend, particularly in alternative meat, has attracted attention from specialized brands and eco-friendly food companies, leading to increased interest in plant-based alternatives. The dominant plant-based proteins, derived mainly from legumes, include soy protein isolates, which significantly impact sensory factors. In the realm of plant-based fats, substitutes are categorized into fat substitutes based on fats and fat mimetics based on proteins and carbohydrates. The production of these fats, utilizing gums, emulsions, gels, and additives, explores characteristics influencing the appearance, texture, flavor, and storage stability of final plant-based products. Analysis of plant-based proteins and fats in hamburger patties provides insights into manufacturing methods and raw materials used by leading alternative meat companies. However, challenges persist, such as replicating meat's marbling characteristic and addressing safety considerations in terms of potential allergy induction and nutritional supplementation. To enhance functionality and develop customized plant-based foods, it is essential to explore optimal combinations of various raw materials and develop new plant-based proteins and fat separation.

Plant-based foods as meat and fat substitutes

Animal proteins have in the past been used in food production due to their functional properties that range from gelation and emulsification to foaming ability and stability. However, animal husbandry has been shown to be a major contributor to global warming and climate change. Consequently, there has been a drive toward the use of alternative proteins, for example, proteins from plant sources which are perceived to be cheaper, healthier, and sustainable. The use of trans and saturated fatty acids in the food industry has been associated with various health issues that include an increased risk of metabolic disorders. This has resulted in an increased search for fat substitutes that are healthier and sustainable. To contribute toward a reduction in the consumption of meats from animal sources and the consumption of trans and saturated fatty acids, the formulation of plant-based meat and fat analogs/substitutes has been carried out. However, there has been a lower acceptance of these meat or fat substitutes which was attributed to their sensorial and textural properties that fail to mimic or resemble real fat or meat. Therefore, this review aims to discuss the advances that have been made when it comes to plant-based meat and fat substitutes. Additionally, consumer perception and acceptance of these products will be reviewed as well as future markets will be discussed and the opportunities and challenges that exist in the formulation of these products will be explored.

Self-Healing Oxalamide Organogelators of Vegetable Oil

The aim of this study was to assess the gelling potential of chiral oxalamide derivatives in vegetable oils. Special emphasis was given to the potential applications of the examined oil gels as sustained delivery systems and as fat substitutes in food products. The applicability of oil gelators is envisaged in food, cosmetics, and the pharmaceutical industry. The regulations requiring the elimination of saturated fats and rising concerns among consumers health motivated us to investigate small organic molecules capable of efficiently transforming from liquid oil to a gel state. The oxalamide organogelators showed remarkable gelation efficiency in vegetable oils, thermal and mechanical stability, self-healing properties, and a long period of stability. The physical properties of the gels were analysed by TEM microscopy, DSC calorimetry, and oscillatory rheology. The controlled release properties of acetylsalicylic acid, ibuprofen, and hydrocortisone were analysed by the LC-MS method. The influence of the oil type (sunflower, soybean, and olive oil) on gelation efficiency of diverse oxalamide derivatives was examined by oscillatory rheology. The oxalamide gelators showed thermoreversible and thixotropic properties in vegetable oils with a minimum gelation concentration of just 0.025 wt%. The substitution of palm fats with gelled sunflower oil applied in cocoa and milk spreads at gelator concentrations lower than 0.2 wt% have shown promising viscoelastic properties compared to that of the original food products.

Effect of Palm-Based Shortenings of Various Melting Ranges as Animal Fat Replacers on the Physicochemical Properties and Emulsion Stability of Chicken Meat Emulsion

This study evaluated the effects of palm shortenings (PS) with varying melting ranges (MR) on the physicochemical, emulsion stability, rheological, thermal, textural, and microtextural properties of chicken meat emulsions. Six emulsions were developed: control (chicken skin), sample A (PS at MR of 33-36 °C), sample B (PS at MR of 38-42 °C), sample C (PS at MR of 44-46 °C), sample D (PS at MR of 45-49 °C), and sample E (PS at MR of 55-60 °C). There were no significant differences in cooking loss, pH, and water-holding capacity between the meat emulsions, with sample E providing a more stable emulsion with the lowest fat content and highest moisture content. The colour profiles and protein thermal stabilities of the fat-replaced meat emulsions were not significantly different from the control. The hardness, shear force, storage, and loss moduli increased when palm shortenings with higher melting range were used, with sample E having the highest values. Sample E also exhibited a smaller pore size and more compact structure, and thus was well-emulsified compared to the other samples. Overall, palm shortenings-particularly those with a melting range of 55-60 °C-have the potential to replace chicken skin in meat emulsions.

Exploring how changes to the steroidal core alter oleogelation capability in sterol: γ-oryzanol blends

Oleogels based on sterols such as β-sitosterol blended with the sterol ester γ-oryzanol are a very interesting class of systems, but there are aspects of their formation and structure that remain elusive. It has previously been shown that a methyl group on the C30 position of the sterol-ester plays an important role in gelation. This work explored the effect that having C30 methyl groups on both the sterol and the sterol-ester had on the gelation process and subsequent gel structure. Lanosterol and saponified γ-oryzanol (which was synthesized as part of this study) were identified as materials of interest, as both feature a methyl group on the C30 position of their steroidal cores. It was observed that both sterols formed gels when blended with γ-oryzanol, and also that lanosterol gelled sunflower oil without the addition of γ-oryzanol. All of these gels were significantly weaker than that formed by β-sitosterol blended with γ-oryzanol. To explore why, molecular docking simulations along with AFM and SAXS were used to examine these gels on a broad range of length scales. The results suggest that saponified γ-oryzanol-γ-oryzanol gels have a very similar structure to that of β-sitosterol-γ-oryzanol gels. Lanosterol-γ-oryzanol gels and pure lanosterol gel, however, form with a totally different structure facilitated by the head-to-tail stacking motif exhibited by lanosterol. These results give further evidence that relatively slight changes to the molecular structure of gelators can result in significant differences in subsequent gel properties.

The Effect of Partial Substitution of Beef Tallow on Selected Physicochemical Properties, Fatty Acid Profile and PAH Content of Grilled Beef Burgers

The objective of this study was to analyze the impact of partial replacement of beef tallow with sunflower, canola, linseed, olive oil and milk fat on physical properties, oxidation stability, fatty acid profile and PAHs (polycyclic aromatic hydrocarbons) content of beef burgers. Studies have shown a strong relationship between the fatty acid profile and the PAH content (especially of the heavy PAHs). The partial replacement of beef tallow with oils and milk fat (MF) contributed to a change in the fatty acid profile and a reduction in the hardness of the burgers. The highest PAH content was found in samples with canola oil (CO), which had the highest levels of monounsaturated fatty acids (MUFA), and in the control group (CON) without fat substitution, which had the highest levels of saturated fatty acids (SFA) and trans conformations. Substitution of animal fat with vegetable oils contributed to a change in the color of the burgers’ surface, as there was a statistically significant increase in the L* color component and a decrease in the a* component. The burgers with canola oil (CO) and linseed oil (LO) were the most susceptible to oxidation, whereas the burgers with reduced fat content (CON_LOW FAT) were the most stable in terms of oxidation, where the malondialdehyde (MDA) content was 32.8% lower compared with the control group (CON). The studies confirm that partial replacement of beef tallow with vegetable oils and milk fat and reduction in fat content in burgers to be grilled can be an effective way to change their fatty acid profile and reduce the cyclization reaction of organic compounds leading to the formation of PAH. Correlation coefficient analysis showed that there is a relationship between fatty acid profile and the presence of selected PAHs in grilled beef burgers. The results of this study indicate that replacing beef tallow with vegetable oils is a promising approach in designing meat products with controlled PAH content.

The Potential Use of Cold-Pressed Pumpkin Seed Oil By-Products in a Low-Fat Salad Dressing: The Effect on Rheological, Microstructural, Recoverable Properties, and Emulsion and Oxidative Stability

The cold-pressed pumpkin seed oil by-product (POB) was evaluated for its application as a natural fat substitute and stabilizer in the reduced-fat salad dressings. For this aim, the samples were prepared by combining the xanthan gum (0.2–0.4 g/100 g), POB (1.0–5.0 g/100 g), egg yolk powder (3 g/100 g), and sunflower oil (10–30 g/100 g) in 17 different formulations. The optimization was carried out using response surface methodology (RSM) and full factorial central composite design (CCD). Results showed that all samples presented the shear-thinning (or pseudoplastic) flow behavior with 3.75–16.11 Pa·sⁿ and 0.18–0.30, K and n values, respectively. The flow behavior rheological data were fitted to a power-law model (R² > 0.99). The samples with high POB and low oil content showed similar K and n values compared to high oil content samples. Additionally, the dynamic rheological properties and three interval thixotropic test (3-ITT) were determined. The G′ value was larger than G″ in all frequency ranges, indicating viscoelastic solid characteristics in all samples. The optimum formulation was determined as 0.384% XG, 10% oil, and 3.04% POB. The samples prepared with the optimum formulation (POBLF-SD) were compared to low-fat (LF-SD), and high-fat (HF-SD) control salad dressing samples based on the rheological properties, emulsion stability, oxidative stability, zeta potential, and particle size. The oxidation kinetic parameters namely, IP, E_a, ΔS⁺⁺, and ΔG⁺⁺ showed that the oxidative stability of salad dressing samples could be improved by enriched by POB. The results of the present study demonstrated that POB could be considerably utilized as a natural fat substitute and stabilizer in salad dressing type emulsions.

The influence of fat substitution with κ-carrageenan, konjac, and tragacanth on the textural properties of low-fat sausage

Reducing the fat content of meat products and producing healthier products is considered as an important matter in politics in prevention of many hazardous diseases and providing consumers' health. The aim of this study was reducing the fat in fatty sausages based on oil reduction and using fat substitutes, including κ-carrageenan, konjac, and tragacanth, and comparing them according to their texture characteristics. κ-carrageenan, konjac, and tragacanth gums were used at four different levels (0.0, 0.5, 1.0, and 1.5) as the fat substitutes in producing low-fat sausage with 70% reduction based on formulated oil. Texture profile analysis (Hardness, Gumminess, Springiness, and Chewiness) was performed in this study for analyzing the texture characteristics, in 1-, 10-, 20-, and 30-day time intervals after production. The results showed that producing low-fat sausage was possible using all the three gums, among the low-fat samples of which, the texture samples containing konjac were more favorable. Textural properties indicated that fat reduction increased in firmness and gum addition can partially compensate deficits in rheological properties, although during the storage, low-fat sausages without any gum have highest decline in Hardness. Konjac gum illustrated the best theological properties between treatments.

Screening of Lipases with Unusual High Activity in the sn-2 Esterification of 1,3-Dicaprin under Mild Operating Conditions

In this work, the synthesis of acylglycerides with high nutritional value was carried out by enzymatic esterification at sn-2 position of 1,3-dicaprin with palmitic acid. A comparative study of the performance of several biocatalysts according to the obtained products was carried out. The results obtained with several of the biocatalysts evaluated are very interesting, and it would be possible to use them to obtain a mixture of acylglycerides to act as a fat substitute. The final product was composed of about 90% of nutritionally attractive glycerides. These glycerides were medium-chain length triglycerides, medium-long chain triglycerides (mainly triglycerides with medium chain fatty acids at sn-1 and sn-3 positions and long chain fatty acid at sn-2 position), and 1,3-diglycerides. Pseudomonas fluorescens lipase and Burkholderia cepacia lipase immobilized on chitosan demonstrated unusual high activity in the sn-2 esterification of 1,3-dicaprin with palmitic acid at 45 °C and 12 h with 33% yield to 1,3-dicaproyl-2-palmitoyl glycerol. Burkholderia cepacia lipase has the advantage of being immobilized; however, BCL/chitosan has the advantages of being immobilized and therefore its easy recovery from the reaction media.