Cheese Dairy Research Articles

Bacterial Removal Separation with a Reduced Throughput Adapted for Artisan Cheese Dairies—Effect on Clostridial Spore Counts and Milk Quality

Bacterial Removal Separation with a Reduced Throughput Adapted for Artisan Cheese Dairies—Effect on Clostridial Spore Counts and Milk Quality

Composite starch/fermented protein emulsion gels for plant-based cheese applications

This work investigated the effect of incorporating lipids and proteins on the properties of starch-based gels relevant for plant-based cheese analogues. Gels were prepared by first fermenting protein-based emulsions to create primary gels, and subsequently using the water of these primary gels as starch hydration media to produce secondary, starch-based, pea protein-rich composite emulsion gels. Fermentation appeared to increase gel hardness compared to non-fermented protein addition. Compared to natural and crosslinked/acetylated starches, the acid-hydrolysed/acetylated starch produced firmer gels and was selected for further experimentation. Gels were macroscopically homogeneous but microscopically showed lipid coalescence at increasing lipid content (>8%), which was reduced by ultrasonicating the emulsion prior to fermentation. Dry matter content was key in determining textural and rheological properties of the gels, with starch/protein gels of 36% dry matter showing hardness and viscoelastic properties similar to those of the dairy cheese Danbo. However, the composite gels did not melt on increasing temperature up to 80 °C (delta below 20°). Proton dynamics were found to depend on gel properties and lipid addition. Overall, this work contributes towards the development of plant-based cheeses with desired characteristics by increasing their protein content and modulating their properties through fermentation and syneresis.

A novel approach to energy management in the dairy industry using performance indicators and load profiles: Application to a cheese dairy plant in Tuscany, Italy

The available energy monitoring information in the dairy industry reveals significant gaps regarding the impact of operational factors on performance indicators and the generation of typical days from load profiles. This paper presents a method for predicting performance indicators and load profiles in the dairy industry based on multiple regression and clustering. The method is applied to a cheese dairy plant located in Tuscany, Italy, providing actionable insights for energy efficiency and renewable integration. With regard to performance indicators, predictions using multiple regression achieved accuracies within 8 % for electricity consumption and within 20 % for steam generation, mainly due to limited data availability. The combination of k-means clustering with multiple regression yielded an overall accuracy within approximately 10 % for electricity load profiles, enabling the labelling of clusters based on production and meteorological variables. The analysis of improved production planning and the compatibility of energy demand with solar resources showed potential reductions in the electrical performance indicator by 27 % and self-consumption rates between 14 % and 42 %, respectively. Validation with data from other dairy contexts confirms the accuracy of the method and the considerable potential for improvement, suggesting further implementation towards effective energy management in the dairy industry.

Can plant-based cheese alternatives be characterized by methods for dairy cheese? Extending dairy cheese methods to characterize plant-based cheese alternatives

The techno-functional properties of dairy cheeses are often superior to their plant-based cheese alternatives. However, the constant increase in demand for plant-based cheese alternatives makes it important to achieve texture and functionality as in dairy cheeses. In this study commercial dairy cheeses and plant-based cheese alternatives were analyzed in regard to chemical composition, texture properties (unheated and heated state) and melting behavior with methods commonly applied to dairy cheeses. Especially, during an oscillatory temperature sweep, data did not show the “melting” the consumer notices while baking the product in an oven as done in the Schreiber test (2_CA, 3_CA). Therefore, a large amplitude oscillatory strain method (LAOS 60 °C) was applied and linked with the results obtained from the Schreiber test and the temperature sweep measurements. LAOS not only showed good correlation with the melting behavior observed in the Schreiber test but also allowed conclusions about the microstructure of the samples.

Health and functional advantages of cheese containing soy protein and soybean-derived casein.

The global food system faces a challenge of sustainably producing enough food, and especially protein, to meet the needs of a growing global population. In developed countries, approximately 2/3 of protein comes from animal sources and 1/3 from plants. For an assortment of reasons, dietary recommendations call for populations in these countries to replace some of their animal protein with plant protein. Because it is difficult to substantially change dietary habits, increasing plant protein may require the creation of novel foods that meet the nutritional, orosensory, and functional attributes consumers desire. In contrast to plant-based milks, plant-based cheeses have not been widely embraced by consumers. The existing plant-based cheeses do not satisfactorily mimic dairy cheese as plant proteins are unable to replicate the functional properties of casein, which plays such a key role in cheese. One possible solution to overcome current constraints that is currently being explored, is to produce hybrid products containing soy protein and soybean-derived casein. Producing soybean-derived casein is possible by utilizing traditional genetic engineering tools, like Agrobacterium-mediated plant transformation, to express genes in soybeans that produce casein. If a cheese containing soy protein and soybean-derived casein satisfactorily mimics dairy, it presents an opportunity for increasing plant protein intake since US dairy cheese consumption has been steadily increasing. Soybeans are an excellent choice of crop for producing casein because soybeans are widely available and play a large role in the US and world food supply. Additionally, because a casein-producing soybean offers soybean farmers the opportunity to grow a value-added crop, expectations are that it will be welcomed by the agricultural community. Thus, there are benefits to both the consumer and farmer.

Nutritional and microbial profiles of ripened plant-based cheese analogs collected from the European market

Plant-based cheese analogs have emerged as a novel global market trend driven by sustainability concerns for our planet. This study examines eleven soft ripened plant-based cheese analogs produced in Europe, primarily with bloomy rinds and cashew nuts as the main ingredient. First, we focused on exploring the macronutrients and salt content stated on the labels, as well a detailed fatty acid analysis of the samples. Compared to dairy cheeses, plant-based cheeses share similarities in lipid content, but their fatty acid profiles diverge significantly, with higher ratio of mono- and polyunsaturated fatty acids such as oleic and linoleic acids. We also investigated the microbiota of these analog products, employing a culture-dependent and -independent approaches. We identified a variety of microorganisms in the plant-based cheeses, with Lactococcus lactis and Leuconostoc mesenteroides being the dominant bacterial species, and Geotrichum candidum and Penicillium camemberti the dominant fungal species. Most of the species characterized are similar to those present in dairy cheeses, suggesting that they have been inoculated as culture starters to contribute to the sensorial acceptance of plant-based cheeses. However, we also identify several species that are possibly intrinsic to plant matrices or originate from the production environment, such as Pediococcus pentosaceus and Enterococcus spp. This coexistence of typical dairy-associated organisms with plant associated species highlights the potential microbial dynamics inherent in the production of plant-based cheese. These findings will contribute to a better understanding of plant-based cheese alternatives, enable the development of sustainable products, and pave the way for future research exploring the use of plant-based substrates in the production of cheese analogues.

The influence of pectinase treatments on the characteristics of pre‐treated and lyophilised sunflower meal‐whey blends

SummaryWhey and sunflower meals are primary by‐products of dairy cheese and vegetable oil production, respectively. Due to their widespread abundance, their valorisation could enable the generation of various value‐added food ingredients or products. In this study, an effort was made to utilise enzymatic pectinolysis along with other pre‐treatments to generate mixtures from whey and sunflower meal (SFM). The increasing presence of SFM increased the critical denaturation temperature of the mixtures and induced less protein structural changes. In addition, the presence of complex carbohydrates in SFM enhanced water and oil holding capacities. In general, pectinase and ultrasonication led to enhanced foaming of the mixtures, although the foams were relatively short‐lived. SFM inclusion limited foaming and emulsification capacities of the blends. In most cases, increasing the ratio of SFM to protein resulted in lower total reducing sugars (TRS), suggesting a more limited enzymatic activity. On the other hand, heating temperature or ultrasonication improved the extent of pectinolysis. Pre‐treatments and pectinolysis improved the functional properties of SFM and whey protein concentrate blends and are promising as an alternative protein source in new product applications.

Chemical, nutritional and sensory characteristics of milk and cheeses obtained from autochthonous, cosmopolitan, and crossbred goats

Abstract The aim of this study was to analyse the milk parameters and the chemical, nutritional, and sensory characteristics of cheeses made from the milk of three groups of goats: native Carpathian goat, Anglonubian and crossbred goats (Saanen × Alpine). For this study, milk was collected three times during the grazing season and was processed into rennet semi-hard cheeses according to a traditional recipe in a pre-farm cheese dairy. Samples of the milk were subjected to physicochemical analyses. The chemical composition, vitamin, macronutrient content, and fatty acid profile of the cheeses were determined. The cheeses were also subjected to organoleptic evaluation. The results showed that the factors studied, such as breed and month of milking, had a significant effect on the physicochemical properties and chemical composition of goat milk. The month of milking affected all the milk characteristics studied, with September having the highest values of acidity, dry matter, fat and protein content. The month did not affect the level of basic components in the cheeses, but it influenced the content of vitamins and macronutrients; the cheeses produced in September had significantly higher levels of Mg, K, and vitamin E. The month of milking had, as did the breed of goat, a significant effect on the profile of most fatty acids in the cheeses. As for the breed factor, it affected both the chemical composition and sensory value of the cheeses. Cheeses made from the milk of the native Carpathian goat had the best health-promoting properties: a more favourable fatty acid profile, the lowest PUFA-6/3 ratio, and the lowest atherogenic index. According to the panellists, cheese from the milk of Carpathian goats also had the most distinctive aroma, typical for goat cheese. The research shows that the cheeses made from the milk of the native Carpathian goat had the best health-promoting properties, which confirms the need for further popularisation of the breed and can be the basis for marketing more products.

An integrated approach to explore the microbial biodiversity of natural milk cultures for cheesemaking

The use of natural milk culture (NMC) represents a key factor in PDO Montasio cheeses, contributing to its distinctive sensory profile. The complex microbial ecosystem of NMCs is the result of heat treatment and incubation conditions, which can vary considerably among different production plants. In this study, the microbiota of NMCs collected from 10 PDO Montasio cheese dairies was investigated employing colony counts and metagenomic analysis. Furthermore, residual sugars, organic acids, and volatile profiles were quantitatively investigated. Results showed that Streptococcus thermophilus was the dominant species in all NMCs, and a subdominant population made of other streptococci and L. salivarius was also present. The incubation temperature appeared to be the main driver of biodiversity in NMCs. Metagenomics allowed us to evidence the presence of minor species involving safety (e.g., Staph. aureus) as well as possible functional aspects (Next Generation Probiotics). Statistical analysis based on residual sugars, organic acids, and volatiles' content allowed to correlate the presence of specific microbial groups with metabolites of great technological and sensory relevance, which can contribute to giving value to the artisanal production procedures of NMCs and clarify their role in the creation of the characteristics of PDO Montasio cheese.

Plant-Based Proteins and Their Modification and Processing for Vegan Cheese Production

Plant-based proteins are important macronutrients in the human diet, crucial for cell development in our bodies and for supporting the immune system. Given their nutritional and functional properties, plant-based proteins are excellent candidates for the development of plant-based food. Among other things, plant-based cheese has been identified as a potential enabler for future innovation through improvements in ingredient technology. Unlike traditional dairy cheeses, plant-based cheeses are made from a variety of ingredients such as nuts and legumes that can be fortified with nutrients also found in traditional cheese. Of course, plant-based cheeses still have some nutritional drawbacks, and most of them are processed, which means they contain preservatives, colour additives and high sodium content. Nevertheless, the physicochemical and functional properties of plant-based proteins are of great interest to the food industry and the initial interest in natural sources of plant proteins has recently shifted to the field of modification and processing. This review discusses the natural sources and classification of plant-based proteins and summarises recent studies on processing methods in the production of plant-based cheese.

Effect of saturated and unsaturated fat on the physical properties of plant-based cheese

In many plant-based meat and dairy alternatives, coconut oil is frequently used to replicate the textural and structural properties of animal fats due to its high saturated fat content. Concerns about the health implications of saturated fat and the sustainability of coconut oil call for an exploration into alternative fat combinations in plant-based foods. The effects of saturated fatty acid (SFA) content on plant-based cheese physical characteristics were evaluated through five different ratios of coconut oil (CO) to sunflower oil (SO): 100%, 90%, 75%, 60%, 50%, 40%, 25%, 10%, and 0%. As determined through texture profile analysis, the hardness of the cheeses after setting at 5°C for 24h increased with increasing amounts of coconut oil due to the increasing solid fat content providing additional firmness. The samples with 100% coconut oil displayed satisfactory melt and stretch; however, the melt and stretch values were matched by adding as little as 25% sunflower oil. The melt and stretch values did not continue to increase with increasing saturated fat content but instead remained constant with increasing coconut oil addition. Rheological analysis of the cheeses during a temperature ramp from 20 to 95°C was assessed where the tanδ value at 95°C was used as a measure of cheese melt, where values ≥ 1 indicated a better melt. The 0% coconut oil cheese had the lowest tanδ (G″/G′) value of 0.3, whereas the addition of 25% coconut oil into the cheese resulted in the tanδ increasing to values greater than 0.5. The 25% CO cheese sample also achieved a more similar complex viscosity (η*) to that of dairy cheese than all samples but the 75% CO cheese. Therefore, there is an opportunity to decrease the amount of coconut oil in plant-based cheese systems while maintaining good functional properties and improving the sustainability and health benefits of the final product.

The effect of various spices on functional properties of plant-based cheese analogue

This research purpose was to study the effects of various spices on functional properties of plant-based cheese analogue (PBCA). PBCA was made from Geotrichum candidum (Gc: 3%), glucono-δ-lactone (GDL: 0.25%), and bromelain: 8 × 105 U/g. The sample was commercial dairy cheese (control), PBCA 1 (Gc + bromelain), PBCA 2 (GDL + bromelain), PBCA 3 (Gc + GDL), and PBCA 4 (Gc + GDL + bromelain). The results of observations processed using ANOVA and DMRT. In this study, different spices affect the chemical and sensory features of PBCA (p<0.05). The chemical features results were ash content (1.92%; 1.51%; 1.57%; 1.74%; 1.39%), fat content (29.7%; 25.0%; 24.9%; 26.7%; 24.7%), moisture content (55.4%; 49.6%; 50.1%; 47.3%; 50.3%), protein content (6.39%; 17.5%; 17.2%; 19.5%; 17.0%), and salt content (0.69%; 0.29%; 0.31%; 0.32%; 0.28%), respectively. The sensory features results were appearance (7.52; 7.18; 7.27; 7.48; 6.85), flavor (8.05; 7.68; 7.33; 7.67; 7.71), creaminess (7.73; 7.35; 7.33; 7.67; 7.25), firmness (6.40; 7.04; 6.37; 6.66; 6.58), spread ability (7.82; 7.48; 7.40; 7.78; 7.25), and overall (8.44; 7.91; 7.80; 7.48; 8.03), respectively. The effectiveness index test result was 1.00; 0.45; 0.53; 0.00; and 1.00, respectively. In conclusion, PBCA 4 was the best treatment.

Diagnosis of the microbiological quality of fiscal artisanal Minas cheese samples

Minas Gerais State is the largest producer of artisanal cheeses in Brazil. In order to preserve production traditions and guarantee sanitary quality, the laws, decrees and other regulations have been constantly updated. Considering its inspection duties and aiming to identify compliance with the microbiological requirements defined in the legislation, the Instituto Mineiro de Agropecuária (IMA) took 1390 indicative samples of Artisanal Minas Cheese (AMC) from 364 cheese dairies in the micro-regions of Araxá, Campo das Vertentes, Canastra, Cerrado, Serra do Salitre, Serro and the Triângulo Mineiro. Coliforms at 35 °C, Escherichia coli, coagulase-positive staphylococci, Salmonella spp. and Listeria monocytogenes were analyzed at the Laboratory of Microbiological Safety in Food at IMA, according to the analytical methodologies determined by the Brazilian Ministry of Agriculture, Livestock and Supply. The mean coliform count at 35 °C, E. coli and coagulase-positive staphylococci ranged from 1.0 to 5.3 log CFU/g, 0.3 to 3.3 log CFU/g and 1.0 to 6.3 log CFU/g, respectively. Thus, 18.7%, 14.1% and 25.0% of the samples, respectively, did not conform with the legislation for these microbial groups. In addition, Salmonella spp. was present in one sample and L. monocytogenes in seven samples. The percentage of non-compliance per micro-region analyzed was 30% in Araxá, 29% in Campo das Vertentes, 23% in Canastra, 44% in Cerrado, 32.5% in Serra do Salitre, 50% in Serro and 20% in the Triângulo Mineiro. Of the cheeses sampled before completing the minimum period of ripening required by state legislation, 51.5% were non-compliant, while for those that completed the minimum time, this index was 24.2%, evidence that the ripening time is essential for the adequacy of AMC to the microbiological standards. On the other hand, the percentages of non-compliance showed very similar values (39.3% and 42.0% respectively) in the dry and rainy seasons. When evaluating the evolution of microbiological quality over 11 years, and comparing the micro-regions, no tendency for improvement in quality was found, and of the hygiene indicator microorganisms, coagulase-positive staphylococci were responsible for the highest number of nonconformities, especially in the Serro regions. Thus, there is a need to implement projects and public policies to improve the microbiological quality of the AMC.

The Application of Raw Chickpeas and Nuts in the Development of Plant-Based Cheese Snack: Ideal Nutrition and Texture Properties

Human and global health would be greatly improved by replacing animal-based foods with plant-based alternatives. This transition would be facilitated when more affordable, convenient, sustainable, nutritious, and tasty plant-based foods are available on the market. Interest in related research has surged these years, and dozens of plant-based cheese (PBC) products have been introduced to the market. However, studies found that most PBCs are far from comparable with dairy cheese in nutritional value, and the texture and sensory properties are still hurdles to the widespread consumption of PBCs. This paper focused on the “tissue disruption route” and adopted chickpeas and nuts as the main ingredients to form a cheese snack. Test results showed that our samples were high of nourishment value compared to the cheese sample and even healthier than the cheese in the terms of energy ( 709.37 ± 1.35 vs. 865.63 ± 0.49 kJ/100 g, p &lt; 0.01 ), K/Na ratio ( 142.00 ± 0.82 / 13.33 ± 0.12 mg/100 g vs. 121.67 ± 2.05 / 44.23 ± 0.05 mg/100 g, p &lt; 0.01 ), DF ( 6.99 ± 0.01 g/100 g vs. N/A, p &lt; 0.01 ), and cholesterol ( 8.81 ± 0.25 vs. 207.30 ± 3.35 mg/100 g, p &lt; 0.01 ). From the order of magnitude, the PBC samples are similar to the cheese sample in the aspects of cohesiveness ( p &lt; 0.05 ) in texture test, and the fermentation process improved the imitation of texture properties in terms of hardness and cohesiveness (both p &lt; 0.05 ). The volatile compounds were similar between the two PBC samples; however, the fermentation process could increase the species of the volatile compounds and make the PBC a little more similar to the dairy cheese. Overall, the observed properties of our PBC snack using raw chickpeas and nuts make the “plant-based cheese substitutes” extremely promising because of their nutritional value, sensory, and texture properties.

Leuconostoc performance in soy-based fermentations – Survival, acidification, sugar metabolism, and flavor comparisons

Leuconostoc spp. is often regarded as the flavor producer, responsible for the production of acetoin and diacetyl in dairy cheese. In this study, we investigate seven plant-derived Leuconostoc strains, covering four species, in their potential as a lyophilized starter culture for flavor production in fermented soy-based cheese alternatives. We show that the process of lyophilization of Leuconostoc can be feasible using a soy-based lyoprotectant, with survivability up to 63% during long term storage. Furthermore, the storage in this media improves the subsequent growth in a soy-based substrate in a strain specific manner. The utilization of individual raffinose family oligosaccharides was strain dependent, with Leuconostoc pseudomesenteroides NFICC99 being the best consumer. Furthermore, we show that all investigated strains were able to produce a range of volatile flavor compounds found in dairy cheese products, as well as remove certain dairy off-flavors from the soy-based substrate like hexanal and 2-pentylfuran. Also here, NFICC99 was strain producing most cheese-related volatile flavor compounds, followed by Leuconostoc mesenteroides NFICC319. These findings provide initial insights into the development of Leuconostoc as a potential starter culture for plant-based dairy alternatives, as well as a promising approach for generation of stable, lyophilized cultures.

Cheese without cows: Consumer demand for animal-free dairy cheese made from cellular agriculture in the United Kingdom

Abstract We examine consumer demand for animal-free dairy cheese produced using cellular agriculture. Our data is generated through a hypothetical choice experiment completed by 1249 UK residents. Using a mixed logit model, we predict that animal-free dairy cheese would have a conditional market share of 22% when priced at a 25% markup relative to premium conventional cheese. However, the market share is quite sensitive to price: only 2% of consumers would purchase animal-free dairy cheese if it were twice the price of premium conventional cheese. Three-quarters of consumers who purchase animal-free dairy cheese would have purchased conventional dairy cheese if animal-free dairy cheese were unavailable. We use our experimental results to examine the impact of higher conventional dairy cheese prices, such as those that might result from a tax on livestock products. We find that the introduction of animal-free dairy cheese reduces consumer losses from higher conventional dairy prices by about 20%.

Efects of Pasteurized Sheep's Milk Use on Production and Ripening of Siirt Herby Cheese

Siirt herby cheese is a varietty of local cheeses, and raw sheep’s and goat’s milk are used in its production. The curds obtained by curdling the milk obtained in the highlands is sold in the city centre during the day or the next day. Siirt herby cheese is produced from the retail curds. Three different cheese samples form retail curd, raw sheep’s and pasteurized sheep’s milks were made. The samples were ripened at 4°C for 120 d. Hygienic quality of raw milk supplied from a farm and raw milk curd bought from local retailers did not have adequate hygiene. Coagulase positive staphylococci were 3.11±0.6 log10 CFU/ml in raw milk, then it increased to 6.6±0.5 log10 CFU/g in the curd before salting. Pasteurization of milk was decreased the total count of the coagulase positive staphylococci below the maximum permissible value (103 CFU/g) in the regulation on Microbiological Criteria of the Turkish Food Codex. These samples were only contained &gt;103 CFU/g coagulase positive staphylococci at the 120th d of ripening. The pasteurization of milk allowed to obtain cheese that meets the desired hygienic criteria. In addition, sufficient acidity and pH development were observed in pasteurized dairy cheeses even though starter culture was not used. It was found that the traditional cheese production using both retail curd and raw milk may not be suitable for producing cheese in accordance with the official standards and regulations. It was concluded that in the case of the production of these cheeses, it is not appropriate to offer them for sale before the completion of the legal ripening period of 120 d. It was deemed necessary to conduct further research in order to draw up a production diagram including the parameters of the Siirt herby cheese production process.

Zein improves desirable melt-stretch properties in plant-based cheeses made from pea protein

Plant-based model cheeses made from pea protein isolate (PPI), zein and zein/PPI blends, were made in combination with corn starch, sunflower oil, different levels of κ-carrageenan (κC) and CaCl2 (CC), and glycerol as a zein-plasticizer. Their viscoelastic properties at ambient temperature and upon heating, as well as their lubrication properties were analyzed. The properties of all plant-based formulations were compared to two dairy cheeses of reference: mozzarella and raclette. Formulations containing PPI formed a gel, whose network structure did not weaken upon heating. In contrast, zein-based cheeses showed potential for structure weakening during heating, as observed during the rheological temperature sweep. The latter observation increased in zein/PPI-combinations with increasing zein content, even though the melting behaviour of any of the plant-based formulations was not fully comparable to the one of raclette cheese. All of the examined formulations reduced the friction coefficient by a factor between 2 and 10 in the boundary regime, compared to HEPES-buffer. In zein-containing formulations, the friction coefficients decreased to a lesser extent the higher the zein proportion was. Finally, the inclusion of κC or CC did not have a significant influence in the lubrication properties of PPI-formulations. In summary, particularly zein/PPI-combinations made of a total protein content of 30% in the formulation showed good potential in mimicking the melting of conventional cheese, opening prospect for the development of formulations with improved sensory characteristics in future works.

Melting properties of vegan cheese: Effect of emulsion and protein addition on the thermal behaviour of starch gels

The aim of this study was to understand the effect of emulsion and protein incorporation on the structural and melting properties of starch gels designed as model systems for specific types of vegan cheese, and to explore the potential of using these ingredients to mimic the melting properties of dairy cheese. To characterise the melting properties of the gels, temperature sweep tests were conducted. In addition, pictures were taken to visualise changes in appearance upon increasing temperature. The microstructure of the gels was investigated with confocal laser scanning microscopy (CLSM). Whereas gels of native maize starch did not melt, those made from oxidised potato starch melted completely at temperatures above 70 °C, resulting in a fluid with a viscosity much lower than that of molten dairy cheese. With the addition of a protein-stabilised sunflower oil emulsion, at oil contents >10%, an oil droplet network was formed in the starch matrix, which partly inhibited the melting of the gel. The addition of pea protein that was subsequently heated together with the starch also resulted in the formation of a network that limited melting. However, due to the high degree of pea protein aggregation, an inhomogeneous appearance was obtained. At low protein contents syneresis occurred. When protein was added without heat treatment, the melting degree was inhibited already at low contents, a more homogeneous appearance was obtained, and syneresis was prevented due to the high-water holding capacity of the protein. When emulsion and protein were added together at high contents, the appearance was also more homogeneous, and the melting degree of the composite gels was further limited. When comparing the relative inhibiting effect of oil and protein content on melting, protein was found to be more effective. By changing both oil and protein content, samples with melting properties similar to those of processed cheese were obtained, which shows that the design of multi-component starch-protein-oil gels is a promising approach in optimising the functional properties of dairy cheese substitutes.

Plant lipid sources in fermented pea protein gels: Emulsion stability and gel microstructure

Lipids play an important role in cheese texture. Their quantity, type and structural characteristics can have adverse effects on product quality. In this study, sunflower oil, oleosomes, oleogel, and coconut oil, were included in pea protein emulsions that were further fermented into pea protein gels and compared to a dairy fresh cheese. The effect of different lipid sources on emulsions stability and on gel structure was evaluated. The different fat sources did not have any significant effect on emulsion stability. The hardness of the dairy cheese, assessed by texture analysis, was found significantly higher than the pea protein counterparts. However, no significant differences were found between the rheological properties of the pea protein gels containing oil, oleosomes, and oleogel and the dairy cheese of reference. Although the protein network is a dominant factor for gel firmness, this study shows that it is possible to produce fermented pea protein gels containing oil, oleosomes, or oleogel with very similar rheological properties to those of a dairy fresh cheese.