Replacing the animal fat in Bologna sausages using high internal phase emulsion stabilized with lentil protein isolate (Lens culinaris).

High internal phase emulsions (HIPEs) are promising techniques that can replace saturated fat in food without reducing the product's texture, sensory attributes, water-holding capacity, and cooking loss. In the current investigation, 100% pork back fat was replaced by HIPEs formed with lentil protein isolate (LPI) in Bologna sausages. HIPEs were prepared by 25% LPI dispersion (2, 4, 6, and 8%, w/w) and 75% (w/w) soybean oil. HIPEs with higher LPI concentration (4, 6, and 8%, w/w) showed lower droplet size, firmer appearance, and better rheology behavior than 2% LPI. The concentrations LPI (2%, 4%, 6%, and 8%, w/w) led to increased moisture in sausages (FH2, FH4, FH6, and FH8, respectively) compared to the FC. These LPI levels resulted in sausage values for pressed juice similar to the FC and lower energy values than sausages with soybean oil (FO) and pork back fat (FC). Besides, these LPI concentrations (4%, 6%, and 8%, w/w) resulted in a lower oil oxidation level in sausages with HIPEs (FH4, FH6, and FH8, respectively) compared to the control sausage formulation with pork back fat (FC). Bologna sausages elaborated with HIPEs showed emulsion stability values higher than 97%, without significance difference between them. The texture and sensory properties of sausages made with HIPEs were comparable to those made with pork back fat. HIPEs may improve the oxidation stability of the Bologna sausages. These results highlight the effectiveness of HIPEs structured with lentil protein in successfully substituting pork back fat in Bologna sausages with a better nutritional appeal.

Unlocking hot trub's potential: a simple method for extracting bitter acids and xanthohumol.

BACKGROUND: Hot trub is a macronutrient- and micronutrient-rich by-product generated in the brewing industry, which is still underrated as a raw material for reprocessing purposes. In this context, this study aimed to investigate the extraction of bitter acids' and xanthohumol from hot trub as well as identify the significance of parameters for the process. The research assessed various extraction parameters, such as pH, ethanol concentration, temperature, and solid-to-liquid ratio, using a Plackett-Burman design. RESULTS: Ethanol concentration and pH were the most significant parameters affecting extraction yield. ß-acids were found to be the principal components of the bitter acids, with a maximum concentration near 16 mg g-1, followed by iso-α-acids and α-acids achieving 6 and 3.6 mg g-1, respectively. The highest yields of bitter acids were observed in the highest ethanol concentration, while pH was relevant to extraction process in treatments with low ethanol ratios. Concerning the xanthohumol extraction, the approach achieved maximum concentration (239 µg g-1) in treatments with ethanol concentration above 30%. Despite their variances, the phytochemicals exhibited comparable extraction patterns, indicating similar interactions with macromolecules. Moreover, the characterization of the solid residues demonstrated that the extraction process did not bring about any alterations to the chemical and total protein profiles. CONCLUSION: Ethanol concentration was found to have the most significant impact on the extraction of bitter acids and xanthohumol, while temperature had no significant effect. The solid remains resulting from the extraction showed potential for use as a protein source. © 2024 Society of Chemical Industry.

Does protein deamidation enhance rice protein concentrate's ability to produce and stabilize high internal phase emulsions?

Rice is one of the most consumed grains in the world. Rice protein has great nutritional value as a hypoallergenic protein and due to its high lysine content, a limiting amino acid in several other plant protein sources. However, rice protein has low solubility, hampering its use in many applications in the food industry. In this context, alkaline deamidation (0.5 h, 343 K, and pH 11) was applied to modify the protein structure of rice protein concentrate (RPC). After deamidation, two protein powders were produced: (i) one containing the whole protein fraction recovered after RPC deamidation (DT) and (ii) another containing only the soluble fraction recovered after RPC deamidation (DS). Protein dispersions were characterized by SDS-PAGE, zeta potential, solubility, surface hydrophobicity, and capacity to hold water and oil. RPC could not structure canola oil into a high internal phase emulsion (HIPE) due to its low solubility. DT and DS dispersions displayed solubility much higher than RPC and enabled the structuration of HIPEs with 75 % (w/w) canola oil and 25 % of DT or DS dispersions (2, 4, and 6 % w/w). HIPEs were characterized regarding particle size, microstructure, Turbiscan and oil loss stabilities, and rheological behavior for 60 days. Turbiscan analysis and oil loss measurements showed high stability, and the thixotropy tests showed high recovery in all HIPEs. Higher protein concentrations and DS dispersions produced HIPEs with smaller particle sizes. However, rheological measurements indicate that HIPEs produced with DT dispersions had better results, maintaining their structure over the 60 days. Furthermore, DT is cheaper to produce; therefore, DT 4 and 6 % w/w were the most promising for producing HIPEs. The HIPEs produced in this study displayed great potential as fat replacers.

Thermo-induced changes in the structure of lentil protein isolate (Lens culinaris) to stabilize high internal phase emulsions.

This study aims to assess the impact of heat treatment on the emulsifying properties of lentil protein isolate (LPI) dispersion to produce high internal phase emulsions (HIPEs). The heat-treated LPI dispersion was characterized by size, turbidity, solubility, zeta potential, free sulfhydryl group, electrophoresis, differential scanning calorimetry, circular dichroism, Fourier transforms infrared spectroscopy and intrinsic fluorescence. HIPEs were produced with 25% of LPI dispersion (2%, w/w) and soybean oil (75%) using a rotor-stator (15,500 rpm/1 min). HIPEs were evaluated for their droplet size, zeta potential, centrifugal stability, microscopy, appearance, Turbiscan stability, and rheology over 60 days (25 °C). Heat treatment reduced the size of LPI, resulting in increased turbidity, solubility, and exposure of hydrophobic groups. HIPEs produced with heat-treated LPI at 70 °C (HIPE70) and 80 °C (HIPE80) for 20 min exhibited lower droplet sizes, increased stability, reduced oil loss, and a homogeneous appearance compared to HIPE produced with untreated LPI (HIPEc). In addition, HIPE70 and HIPE80 displayed resistance to shear stress, higher apparent viscosity, and increased storage modulus than HIPEc. HIPEs produced with heat-treated LPI were stable, suggesting that the treatment was efficient for improving the functional properties of the protein and the possibility of future research focusing on fat substitutes in food applications.

Co-encapsulation of Paprika and Cinnamon Oleoresins by Spray Drying in a Mayonnaise Model: Bioaccessibility of Carotenoids Using in vitro Digestion.

This study aimed to investigate the digestibility and bioaccessibility of spray-dried microparticles co-encapsulating paprika and cinnamon oleoresins using simulated gastrointestinal conditions. It focused on exploring the potential of these co-encapsulated active compounds, which possess diverse technological and functional properties, particularly within a food matrix, in order to enhance their bioavailability. Mayonnaise was selected as the food matrix for its ability to promote the diffusion of carotenoids, as most hydrophobic compounds are better absorbed in the intestine when accompanied by digestible lipids. Model spice mayonnaise, containing 0.5 wt% paprika and cinnamon microparticles content, was formulated in compliance with Brazilian regulations for spices, seasonings, and sauce formulations. Droplet size distribution, optical microscopy and fluorescence microscopy analyses were conducted on the microparticles, model spice mayonnaise, and standard mayonnaise both before and after in vitro gastric and intestinal digestion. Following digestion, all samples demonstrated droplet aggregation and coalescence. Remarkably, dispersed particles (37.40 ± 2.58%) and model spice mayonnaise (17.76 ± 0.07%) showed the highest release rate of free fatty acids (FFAs), indicating efficient lipid digestion. The study found that using mayonnaise as a delivery system significantly increased bioaccessibility (22.7%). This suggests that particles in an aqueous medium have low solubility, while the high lipid composition of mayonnaise facilitates the delivery of active compounds from carotenoids present in paprika and cinnamon oleoresin after digestion.

Oil-in-water emulsion gels stabilized with cellulosic polymers and chitosan: Themorheological and physical-chemical evaluation.

This research evaluated the use of different polymer ratios, hydroxypropyl methylcellulose (HPMC) and methylcellulose (MC) with chitosan (CHI), in the production of emulgel by emulsification. The concentration was fixed at 2 % (w/v) for all polymers. 60/40 sunflower oil-in-water emulgels were made with a cellulosic polymer:chitosan ratio of (80:20), (70:30), and (60:40), respectively. The objective was to study how different proportions of a cellulosic polymer combined with chitosan can affect the stability, microstructure, and rheology of the emulgels to be used as potential oil carrier systems. Droplet size and microscopy results show oil-in-water (O/W) emulgels, and their interface was stabilized by mixing polymeric pairs, HPMC:CHI or MC:CHI. In the thermal analysis, it was identified in the entire temperature range studied (5 to 85 °C) that both emulgels, HPMC:CHI and MC:CHI, were presented as gels (G' > G″). Thus, the addition of CHI to the systems modified their gelling behavior. Microscopy revealed that the emulsions at the 7th and 10th week of storage showed similar characteristics to the fresh emulsion. Therefore, these results indicate that the emulgels present good thermal resistance, the predominance of elastic behavior, and can retain high concentrations of oil in their structure (96 to 99 %).

Co-encapsulation of paprika and cinnamon oleoresin by spray drying using whey protein isolate and maltodextrin as wall material: Development, characterization and storage stability.

The influence of whey protein isolate (WPI), maltodextrin (MD), and their combinations (MD:WPI, 1MD:3WPI, and 3MD:1WPI) as wall materials for the co-encapsulation of paprika and cinnamon oleoresins (OPC) by emulsification followed by spray drying (150 °C, 6 mL/min) were evaluated. The resulting microparticles were evaluated in terms of their physicochemical and morphological properties. They showed irregular surfaces with cavity formation, with mean particle diameter ranging from 15.42 to 33.46 µm. The powders had low Aw values (0.23-0.27); moisture values in the range of 4.45-5.19%; high solubility; and satisfactory encapsulation efficiency (>83%) except for the formulation containing only MD as wall material. After rehydration, the values for droplet sizes were similar to those of the emulsions before drying. Color parameters, carotenoid content, antioxidant activity, and size were evaluated during storage under different storage temperatures (25 and 45 °C) over 90 days. Significant degradation of active compounds over the storage period was observed at 45 °C, resulting in the color change and in greater moisture, Aw, and particle size. The 3MD:1WPI formulation can be considered the best, based on its physicochemical characteristics, good protection of the active compounds during storage, and low cost. The results suggest that these microparticles can be used as dyes and antioxidants in foods.

Model infant formulas: Influence of types of whey proteins and lipid composition on the in vitro static digestion behavior.

This work aimed at evaluating the influence of types of whey proteins (lactoferrin, whey protein isolate and/or whey protein hydrolysates) and lipid composition (high oleic sunflower oil, coconut oil and/or medium chain triacylglycerols) on the behavior of model infant formulas (IFs) under simulated conditions of the infant gastrointestinal tract using an in vitro static digestion model. The physicochemical conditions of the gastric medium resulted in the aggregation of oil the droplets and partial hydrolysis of the proteins, considering whey proteins were resistant to the gastric conditions. However, after intestinal digestion the proteins from all the IFs were extensively hydrolyzed. The lipid composition of the IFs did not influence the protein hydrolysis, but the protein composition of the IFs altered the release of free fatty acids. The presence of lactoferrin in the IFs resulted in a higher free fatty acids release compared to IFs of same lipid composition. In terms of lipid composition, IFs containing coconut oil and medium chain triacylglycerols showed extremely higher free fatty acids release than those containing only long chain triacylglycerols. These results are promising for the design of infant foods containing fast-absorbing functional ingredients.

The porosity of carbohydrate-based spray-dried microparticles containing limonene stabilized by pea protein: Correlation between porosity and oxidative stability.

In this study, the effects of different concentrations of pea protein concentrate (PPC) in the physical properties, porosity features, and oxidative stability of maltodextrin-based spray-dried microparticles containing orange essential oil (OEO, rich in limonene) were evaluated. The use of PPC resulted in spray-dried microparticles with encapsulation efficiencies of about 99 wt%, without visible pores, and relatively high glass transition temperature (66,4 °C) at Aw âˆ¼ 0.3. The nitrogen adsorption and positron annihilation lifetime spectroscopy measurements showed that the increase of PPC concentration from 2.4 to 4.8 wt% (g of PPC/100 g of emulsion) did not affect the porosity features of the microparticles. These results were confirmed by the profiles of OEO retention and limonene oxide production, which were similar for both samples throughout four weeks of storage. Based on these results, we verified that the lower amount of PPC we tested can effectively protect the OEO during storage, showing that a relatively cheaper orange flavor powder can be produced using less protein.

Protein-based strategies for fat replacement: Approaching different protein colloidal types, structured systems and food applications.

In the last decade, food structuring has received considerable attention due to the concern of replacing trans and saturated fats with healthier alternatives without compromising neither technological nor sensorial aspects of food products. Moreover, sustainability topics, consumers' preference for natural ingredients and the molecular architecture displaying a myriad of techno-functionalities embolden the use of proteins. Therefore, a promising approach is to explore this biopolymer as a texture promoter in lipid-based systems, conveying an extra edge in nutritional, sustainable and technological values. A more in-depth comprehension should be cemented to fully harness the potential of proteins in developing soft matter intended for use as fat mimetic. High Internal Phase Emulsion (HIPE), High Internal Phase Pickering Emulsion (HIPPEs), emulgels, oleogels or even bigels can be used in such strategies. Essentially, the formation of such systems relies on the amphiphilic character of proteins. In this sense, the question that arises is how to optimize their solubility in oils to form oil-structured systems? Thus, for oleogel formation the challenge is to overcome the limited dispersibility of proteins in a hydrophobic environment. Therefore, face the growing interest and untapped potential in applying proteins in lipid media, a more wide-ranging picture of their colloidal form (e.g. native, microgels and protein-polysaccharide complexes or conjugates) affecting the structure-function relationship of proteins must be investigated. This review covers different strategies using proteins as building blocks to manufacture different structured systems. Finally, an outlook over the use of protein-based soft matter on an industrial basis is discussed, considering the challenges and perspectives.

Thermo-rheological properties of chitosan hydrogels with hydroxypropyl methylcellulose and methylcellulose.

Thermal and rheological properties of methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) hydrogels with chitosan (CHI) were investigated to verify the potential application of these blends as structured systems for oil transport (emulgel, oleogels, and bigels). FTIR confirmed hydrophobic interactions of cellulosic polymers with chitosan. In the temperature sweep, the thermosensitive hydrogels showed their reduced gel point compared to the original polymers. The gelation temperature was reduced from 66.9 °C for pure HPMC to 43.6 °C and 43.6 °C (MC pure polymer) to 39.3 °C when 30% CHI was added for both cases. The addition of 20 and 30% chitosan is enough to modify the extension of the gelation temperature of these polymers. These results indicate that the addition of chitosan enables MC and HPMC to form gels at lower temperatures, which could allow milder thermal conditions to be applied in processing oil carrier systems.

Supercritical fluids and fluid mixtures to obtain high-value compounds from Capsicum peppers.

Peppers of the Capsicum genus have a rich nutritional composition and are widely consumed worldwide. Thus, they find numerous applications in the food, pharmaceutical and cosmetic industries. One commercial application is oleoresin production, a nonpolar fraction rich in bioactive compounds, including capsaicinoids and carotenoids. Among the technologies for pepper processing, special attention is given to supercritical fluid technologies, such as supercritical fluid extraction (SFE) with pure solvents and CO2 plus modifiers, and SFE assisted by ultrasound. Supercritical fluid-based processes present advantages over the classical extraction techniques like using less solvents, short extraction times, specificity and scalability. In this review, we present a brief overview of the nutritional aspects of peppers, followed by studies that apply supercritical fluid technologies to produce extracts and concentrate bioactives, besides oleoresin encapsulation. Furthermore, we present related phase equilibrium, cost estimation, and the gaps and needs for the full use of peppers from a sustainable perspective.

Cinnamon and paprika oleoresin emulsions: A study of physicochemical stability and antioxidant synergism.

Cinnamon and paprika oleoresins (CPO) are by-products of the spice Cinnamomum zeylanicum Blume and the fruit Capsicum annuum L., respectively. They present a hydrophobic nature and various active compounds that can act synergistically. However, they are both susceptible to degradation by light, oxygen, and temperature. This work aimed at identifying the synergistic effect of these oleoresin mixtures, incorporating them into emulsions and characterizing the obtained systems. The CPO concentration was 10%, and whey protein isolate (WPI), gum Arabic (GA), or maltodextrin (MD) were used as wall materials in different proportions, totalizing 30% solids. The synergistic effect was observed in the FRAP assay at a 1:1 CPO ratio, with its expected value being significantly higher than the values for individual oleoresins (p < 0.05). Emulsions containing GA were unstable, while the emulsions containing MD and WPI showed reduced droplet size and viscosity, remaining stable for 7 days. The sample with a 1:3 proportion of MD:WPI as wall material showed higher FRAP and ORAC antioxidant values (24.74 ± 0.83 and 28.77 ± 1.23 mmol TE/g of oleoresin, respectively) and 4.18 mg total carotenoids/g sample. These results suggest the emulsions have a protective effect on active compounds content and can be used as efficient delivery systems for food product applications.

Effect of pH and Pea Protein: Xanthan Gum Ratio on Emulsions with High Oil Content and High Internal Phase Emulsion Formation.

Electrostatic interaction between protein and polysaccharides could influence structured liquid oil stability when emulsification is used for this purpose. The objective of this work was to structure sunflower oil forming emulsions and High Internal Phase Emulsions (HIPEs) using pea protein (PP) and xanthan gum (XG) as a stabilizer, promoting or not their electrostatic attraction. The 60/40 oil-in-water emulsions were made varying the pH (3, 5, and 7) and PP:XG ratio (4:1, 8:1, and 12:1). To form HIPEs, samples were oven-dried and homogenized. The higher the pH, the smaller the droplet size (Emulsions: 15.60-43.96 µm and HIPEs: 8.74-20.38 µm) and the oil release after 9 weeks of storage at 5 °C and 25 °C (oil loss < 8%). All systems had weak gel-like behavior, however, the values of viscoelastic properties (G' and G″) increased with the increment of PP:XG ratio. Stable emulsions were obtained at pHs 5 and 7 in all PP:XG ratios, and at pH 3 in the ratio 4:1. Stable HIPEs were obtained at pH 7 in the ratios PP:XG 4:1, 8:1, and 12:1, and at pH 5 at PP:XG ratio 4:1. All these systems presented different characteristics that could be exploited for their application as fat substitutes.

Effect of chia oil and pea protein content on stability of emulsions obtained by ultrasound and powder production by spray drying.

Chia oil is susceptible to oxidation and to make this oil application into foodstuffs possible, chia-oil based microparticles were produced. Oil-in-water emulsions were produced by ultrasound and their stability was maximized using a central composite rotational design (X1: pea protein X2: oil concentration). Hi-Cap® 100 (HC) or maltodextrin (MD) were used as carrier agents in spray drying. The validated formulation with 13.50% (w/w) oil and 3.87% (w/w) pea protein presented the best stability conditions (no phase separation for 7 days, monomodal size distribution, and 1.59 µm of moda diameter). Particles showed high encapsulation efficiency (87.71 and 91.97% for MD and HC, respectively) and low water activity and moisture values (0.114-0.150% and 2.64-3.41%, respectively). HC particles exhibited better physicochemical and structural characteristics, apart from their good reconstitution, which shows the potential of this approach as a viable alternative for the use of rich-plant ingredients, such as chia oil and pea protein.

Spent brewer's yeast proteins and cell debris as innovative emulsifiers and carrier materials for edible oil microencapsulation.

Spent brewer's yeast is a by-product rich in proteins, polysaccharides, and fibres. In addition to being nutritive, this material is available in large amounts and can be considered a cheap and sustainable alternative as a carrier material for microencapsulation. The objective of this work was to use the protein hydrolysate of spent brewer's yeast as an emulsifying agent and carrier material for the microencapsulation of sunflower oil by spray drying. A Central Composite Rotational Design (CCRD) was used to determine emulsion's optimal conditions: protein concentration (1.5-6.0%), oil concentration (10-25%) and pH (5.5-7.5) regarding Turbiscan Stability Index (TSI), droplet size and zeta-potential. The validated optimised emulsion containing 4.4% protein and 17.5% oil was produced at a pH value of 6.5. This formulation had a mean droplet diameter of 6.6 ± 0.3 µm, a ζ- potential of -29.0 ± 1.7 mV and a TSI (24 h) of 0.9 ± 0.2%. This emulsion was spray-dried with and without maltodextrin (M20) at 150 and 180 °C. The highest encapsulation efficiency was 55%, achieved at 180 °C with M20, 87% higher than dry powder at the same temperature, but without M20. The water activity of powders without M20 were 58% and 14% lower (0.20 and 0.17) than powders with M20 dried at 150 and 180 °C, (0.13 and 0.15) respectively. The mean particle size was close to 50 µm. The powder without M20, dried at 150 °C, showed the highest stability against oxidation (45 °C for 4 weeks), with a peroxide index of 311 meq of peroxide per kg of oil. Powder properties were evaluated by SEM and FT-IR. Kinetically stable emulsions and particles were produced from spent brewer's yeast ingredients, which were able to act as both carrier materials and emulsifiers, providing a more noble use for an important brewing residue.

Encapsulation of resveratrol using Maillard conjugates and membrane emulsification.

Resveratrol is a stilbene phenolic associated with health-promoting properties such as antioxidant, anti-inflammatory and chemoprevention. Due to its chemical instability and low water solubility, microencapsulation represents a good alternative to provide better results when employing resveratrol as a nutraceutical ingredient. The main purpose of our work was to use low shear membrane emulsification to produce resveratrol-loaded emulsions of low polydispersity and integrate this process to spray drying to produce a powdered product. Resveratrol was dispersed with palm oil in a continuous phase obtained via Maillard reaction. We evaluated the influence of process conditions and phases composition on emulsions properties and performed the characterization of the spray-dried powder. Emulsions droplet size and span decreased as shear stress was increased. Higher dispersed phase fluxes provided increased droplet size polydispersity. Process conditions were set on 60.0 Pa shear stress and 70 L m-2h-1 of dispersed phase flux, obtaining emulsions with mean diameter around 30 µm and span of 0.76. Despite this relatively high droplet size of the infeed emulsions, the spray drying process resulted in particles with high encapsulation efficiency (97.97 ± 0.01%), and water content (~3.6%) and diameter (~10.2 µm) similar to particles obtained from fine emulsions in previously reported works.

Maillard conjugates from spent brewer's yeast by-product as an innovative encapsulating material.

Yeast-based by-products are greatly available, have a rich nutritional composition and functional properties. The spent brewer's yeast (SBY) cells after enzymatic hydrolysis may be a sustainable and low-cost alternative as carrier material for encapsulation processes by spray drying. Our work had as main purpose to characterise the hydrolysed SBY cell debris after the Maillard reaction and to study their potential as a microencapsulation wall material. SBY-based Maillard reaction products (MRPs) were used to encapsulate ascorbic acid (AA) by spray drying. The Maillard Reaction was able to improve the solubility of solids and proteins by 15% and promoted brown color development (230% higher Browning Index). SBY-based MRPs resulted in particles of a high encapsulation yield of AA (101.90 ± 5.5%), a moisture content of about 3.4%, water activity of 0.15, hygroscopicity values ranging from 13.8 to 19.3 gH2O/100 g and a glass transition temperature around 71 °C. The shape and microstructure of the produced particles were confirmed by scanning electron microscopy (MEV), indicating very similar structure for control and AA encapsulated particles. Fourier Transform Infrared Spectroscopy (FT-IR) results confirmed the presence of yeast cell debris in the surface of particles. Ascorbic acid was successfully encapsulated in Maillard conjugates of hydrolyzsd yeast cell debris of Saccharomyces pastorianus and maltodextrin as confirmed by optical microscopy, differential scanning calorimetry, MEV and FT-IR.

Spent brewer's yeast as a source of high added value molecules: a systematic review on its characteristics, processing and potential applications.

Development of new strategies to add-value to agro-industrial by-products are of environmental and economical importance. Innovative and low-cost sources of protein and bioactive peptides have been explored worldwide. Spent brewer's yeast (SBY) is the second most relevant by-product from the brewing industry, and despite its nutritional (about 50% protein, dry weight) and technological potential, it is still underused or needs to be disposed of. SBY cells need to be disrupted to release intracellular and cell wall proteins. This procedure has been performed using autolysis, glass bead milling, enzymatic hydrolysis and ultrasound processing. Enzymatic treatment is usually performed without prior purification and is a challenging process, which involves multiple factors, but has been successfully used as a strategy to add value to agro-industrial by-products. Scope and approach: in this review, we particularly focused on enzymatic hydrolysis as a strategy to promote SBY valorisation, illustrating the state-of-the-art processes used to produce protein extracts from this material as well as exploring fundamental concepts related to the particularities of yeast cell disruption and protein hydrolysis. Furthermore, innovative applications of value-added yeast by-products in food, biotechnological and pharmaceutical industries are presented and discussed. Key findings and conclusions: the discovery of valuable compounds found in spent yeasts as well as the development of new processing methodologies have been widening the possibilities of reuse and transformation of SBY as an ingredient and innovative matrix. Once released, yeast proteins and peptides may be applied as an innovative non-animal protein source or a functional and bioactive ingredient.