Thanks to their agronomical, nutritional and technological interests, pulses are very promising to reach the food-related sustainable development goals (SDG). In developed countries, they typically appear as good substitutes to animal proteins, thereby relieving livestock’s environmental impacts of food systems. However, their share in the Western diet has dramatically declined throughout the 20th century. As a consequence, the release of public data regarding processed pulses is slower than for animal-based food products, while comprehensive comparative evaluation capabilities for animal and plant proteins are deemed necessary. Tremendous effort is therefore currently invested to support the reintroduction of pulses in agricultural practices and food innovations. In this way, life cycle assessment (LCA) is a standard method that quantifies the potential environmental impacts of a manufactured product. In compliance with ISO 14 040 principles and framework, this data paper provides life cycle inventory and life cycle assessment datasets related to the production of two different types of pulse protein ingredients: dry-fractionated protein concentrates from five faba bean varieties and one pea variety, and a wet-fractionated protein isolate from one of the five faba bean varieties. Processing was achieved at a semi-industrial scale using classical technologies used in France in the 2020s. Background data was chosen in the Agribalyse 3.1.1 and Ecoinvent 3.9 databases. In the presented semi-industrial protein concentrate production system, the seeds were sorted, cleaned, dehulled then ground and turbo separated into a protein-rich and a starch-rich fractions. This data paper therefore provides the allocation factors to apply mass, dry matter, protein or economic allocation at dehulling and turbo separation. In the presented semi-industrial protein isolate production system, globulin proteins were extracted from an intermediate flour product by dispersion in water, acid precipitation, neutralization and stabilization into powder. All side streams were regarded as wastes and therefore no allocation was applied. Finally, the data paper provides the potential environmental impacts of 1 kg of each product using the characterization method EF 3.0 and the different allocation rules.
Infant formulas provide the necessary nutrients to infants aged 0-6 months whenever breastfeeding is restrained. Their production must balance nutritional quality, environmental sustainability and economic profitability in the manufacturing process. Traditional heat treatment processes, such as pasteurization, ensure microbiological safety but lead to protein denaturation and Maillard reaction, thereby diminishing the nutritional quality of the product. New processes involve low-heat sanitation using membrane microfiltration to also maintain protein quality. Life Cycle Assessment was used to compare the potential environmental impacts of the production of infant formula powder via the classic route (using pasteurization) or the alternative route (using microfiltration) at a semi-industrial scale. No matter the sanitation procedure, the production of milk and oil ingredients exhibited the largest contribution to impacts, followed by evaporation and spray-drying, i.e. unit operations with energy-consuming water evaporation. Closer insight on sanitation operations revealed that while pasteurization and microfiltration are comparable across various impact categories, microfiltration demands significant water and detergent for cleaning, whereas pasteurization is energy-intensive during its steady-state phase. Although energy consumption is reduced, 1 kg of infant formula produced through the alternative route emits 11.1 kg of CO2 equivalent, against 10.4 for the classic route. The higher impact of the alternative route on climate change, as well as on other agriculture-related impact categories, is primarily attributed to the increased demand for skim milk to implement microfiltration. Sensitivity analyses revealed strategies to reduce infant formula's environmental impacts, such as using liquid ingredients to avoid drying or increasing pre-evaporation dry matter to save energy.
Infant milk formulas are industrial substitutes to human milk, used when breastfeeding is neither possible nor desirable. They are manufactured using successive additions of dry ingredients and oils to skim bovine milk, blending, pasteurization, homogenization, concentration by vacuum evaporation and spray-drying. However, successive heat loads are detrimental to the proteins’ nutritional quality of the final product. An alternative processing route has been proposed that replaces the first pasteurization step at 85 °C by a microfiltration step at 50 °C, i.e. below the heat-denaturation temperature of milk proteins. This data paper provides extensive description of the two processing routes at a semi-industrial scale, using measurements, calculations of the material and energy balances, expert say information, or proxies collected at UMR STLO in the period 2020–2024 and organized into life cycle inventories of all the data required for modelling. This dataset further provides the potential environmental impacts of 1 kg of the classic infant milk powder, as well as of 1 kg of infant milk powder produced using low-heat processing route as an alternative product. The Life Cycle Assessment (LCA) standard method was used, with the CML-IA, ReCiPe 2016, Impact World+, LC-Impact or EF3.0 characterization methods and a dry matter allocation rule for the skimming operation. The dataset further provides variations of the inventories and environmental impact assessments to evaluate the sensitivity of the results to the formula’s dry matter content prior to spray-drying or to the liquid versus dry state of the whey ingredient involved in the formula. The dataset participates in providing LCI of industrial food processes to the public. It will also be helpful for eco-designing classic or innovative processing routes for the manufacture of environmentally sustainable infant milk powders.
Food plays a significant role in the environmental impacts of human activities. However, many agro-industrial processes are multi-product systems and their impacts need to be distributed between the different co-products in order to properly address two major issues: (1) prevention of food spoilage and food losses and (2) the eco-design of food systems, from processing up to recommendations for changes in Western diets. As a culturally and nutritionally central component of most human diets, milk is critical because processing is a preservation issue and most dairy products follow from separations, thereby generating co-products. Life Cycle Assessment (LCA) is a reference and standard method that allows quantification of the potential environmental impacts of a manufactured product throughout its life cycle. Application of the method requires foreground information on the system considered, as well as input and output flows that feed and exit the system. This data paper provides data related to the fractionation of milk into cream, casein, lactose and two whey protein ingredients at industrial scale, using up-to-date technologies used in French dairy factories in years 2000–2010s. Cleaning is included. Transcription of these input and output flows into a selection of processes in the Agribalyse 3.0.1 and Ecoinvent 3.8 databases is also provided. Application of the LCA method in its attributional approach leaves methodological choices up to the practitioner, such as subdivision of the system, allocation of the environmental burden where subdivision is not applied or not possible, and aggregation of the impacts. Therefore, this data paper also provides the allocation factors that are necessary to apply mass, dry matter, protein or economic allocation at every separation operation throughout the processing itinerary. Using the characterization method EF 3.0, this data paper provides the potential environmental impacts of the 5 co-products obtained with an initial input of 600 tons of raw milk, i.e., 63 tons of cream, 183 tons of wet casein, 90 tons of lactose, 1.7 ton of dried β-lactoglobulin and 0.3 ton of dried α-lactalbumin. The respective shares of the 5 co-products are calculated for each allocation rule. Finally, this data paper provides the potential environmental impacts for the manufacture of 1 kg of α-lactalbumin enriched ingredient, as the co-product with the longest process itinerary, with details of all intermediate input contributions as well as two possible aggregation rules: by step or by input type. The dataset participates in providing often confidential industrial-scale LCI data to the public. It will be helpful for the eco-design of future itineraries. In particular, it contributes to taking the fate of the co-products into account when using LCA for such eco-design.
Many industrial food processes are multi-steps, multi-products systems, and sharing the environmental impacts produced by each step to each product is critical when implementing life cycle assessment (LCA) method. The objective of the study was therefore to investigate subdivision and different allocation rules as means of accounting for branched process itineraries such as the fractionation of milk into cream, casein, whey proteins and lactose as a case study. Depending on the mass, dry matter, protein or economic allocation, single products may or may not bear significant environmental impacts, thereby stressing the need for equally detailed inventories for all co-products. Aggregating the results by step or by input further helps identifying hotspots. Methodological choices in LCA of multifunctional systems are therefore strategic decisions that ultimately affect the eco-design of products, processes and food chains.
Reducing consumption of animal-based protein in favor of plant-based protein in Western diets could be a way to mitigate the pressure of our diet on the envi-ronment. However, consumers may find it challenging to re-balance their diet. In particular, milk substitution seems difficult to some consumers, for nutritional and sensory reasons. New products that mix dairy-and plant-based components could be an opportunity to gradually familiarize consumers with plant-based products characteristics. In the present study, attitudes and expectations of French participants toward such dairy and plant-based mixed products were studied through the implementation of online Check-All-That-Apply (CATA) questionnaires using images of fictional mixed products. Participants responded to a single-item food choice questionnaire (SI-FCQ) and a socio-demographic questionnaire. Three profiles were found according to their criteria of food choice. The attitudes and beliefs of participants toward mixed products depended on both the nature of the plant component of the mixed products, and the profile of participants regarding SI-FCQ answers. Mixed dairy and plant-based products may be considered as more than a combination of both ingredients, and even globally as a new object. This opens new perspectives on eating habit changes.
Casein micelles (CMs) are -100 nm natural colloids found in milk resulting from the complex and unresolved association of casein monomers, phosphorus, and calcium; the latter being either directly bound to the phosphoserine residues of caseins or present as nanoclusters of insoluble micellar calcium phosphate (MCP). Dairy products such as cheese or yogurt are colloidal gels formed by CMs destabilization, for which texture and ability to be processed are essentially determined by rheological properties. Those properties depend on the physicochemical conditions used during gel formation (e.g., pH, temperature, ionic content). However, questions remain about the origin of this dependence at the microscopic scale. In particular, we still do not have a clear picture of the specific contributions of the rigidity of the elementary bricks (CMs) in comparison with the inter particles interactions or their spatial distribution. In this work, Atomic Force Microscopy (AFM) is used to evaluate changes in the nanomechanical properties of single CMs following physico-chemical modifications that are known to affect the MCP content and the rheology of the enzymatic milk gel (i.e. decrease of pH and CaCl2 addition). AFM is used as a direct indenter that assesses the CMs' elastic deformation and gives an estimate of their Young modulus. We show that for a +/- 18-24% w/w depletion or enrichment in MCP content, the Young modulus of CMs significantly decreases or increases, respectively. This correlation suggests that variations in the modulus of individual CMs could explain the changes in the macroscopic properties of the enzymatic milk gel upon variations of physico-chemical conditions.
Lactobacillus delbrueckii subsp. bulgaricus is a beneficial lactic acid bacterium and constitutes one of the most used, and thus consumed, dairy starters, worldwide. This homofermentative bacterium was the first lactobacillus described and is involved in the fermentation of yogurt and of diverse other fermented products, including cheeses. It has a long history of safe use, as well as documented probiotic lato sensu effects, including alleviation of lactose intolerance. Plant-based fermented products presently experience a considerable development, as a result of evolution of consumers' habits, in a general context of food transition. This requires research and development, and thus scientific knowledge, to allow such transition, including the development of fermented soy milks. These last indeed offer an alternative source of live and active bacteria. The yogurt starters L. delbrueckii subsp. bulgaricus, together with Streptococcus thermophilus, have been implemented to generate yogurt-type fermented soy milks worldwide. While the adaptation of these starters to the dairy environment has been extensively studied, little is known about L. delbrueckii adaptation to the soy environment. We therefore investigated its adaptation to soy milk and compared it to cow's milk. Surprisingly, it did not grow in soy milk, neither alone, nor in co-culture with S. thermophilus. Acidification of soy milk was however faster in the presence of both species. In order to deepen such adaptation, we then compared L. delbrueckii growth and survival in soy milk ultrafiltrate (SUF, the aqueous phase of soy milk) and compared it to cow's milk ultrafiltrate (MUF, the aqueous phase of cow milk). This comparison revealed major differences in terms of cell morphology and proteome composition. Lactobacilli appeared deformed and segmented in soy. Major differences in both the surface and the cellular proteome indicated upregulation of stress proteins, yet downregulation of cell cycle and division machinery. Altogether, these results suggest that soy milk may be a stressing environment for the yogurt starter L. delbrueckii subsp. bulgaricus.
The article presents a proteomic dataset generated by a comparative analysis, using gel-free nanoLC-MS/MS, of the cellular proteome of Lactobacillus delbrueckii subsp. bulgaricus, a yogurt starter, when cultivated in soy milk versus in cow milk. The CIRM-BIA1592 strain was cultivated in the aqueous phase of soy milk, or of cow milk. Whole-cell proteins were extracted, trypsinolyzed and analyzed by nano LC-MS/MS, prior to identification and to classification by function using the X!Tandem pipeline software and the proteomic data from NCBI.nlm.nigh.gov. Quantification of the proteins was moreover performed to evidence changes in their expression, depending on the culture medium. Data are available via ProteomeXchange with the identifier PXD033905 (http://www.proteomexchange.org/). This article is related to the research article entitled “The stressing life of Lactobacillus delbrueckii subsp. bulgaricus in soy milk”, by G.Jan et al. in Food Microbiology, 2022. This proteomic differential analysis indeed revealed major modulation of the stress proteome, with many stress proteins upregulated in the soy environment.
Background: Since the early 1990s, major health and environmental concerns have developed and driven the emergence of diets involving a lower consumption of animal products. However, the transition towards greener diets is being hampered by the poor acceptance of vegan foodstuffs among western consumers. Mixed animal/plant alternatives to familiar dairy or egg products offer a new field of innovation. Scope and approach: This review focuses on innovative mixes of egg or milk with plant ingredients - especially legumes - to develop products in which interactions between animal and plant are not usually expected, such as dairy or egg gels, emulsions or foams. The opportunities offered by such products in terms of consumer acceptance, nutrition, digestibility and techno-functional properties are reviewed and discussed with respect to their risk-benefit ratios. Key findings and conclusions: In many cases, animal/plant mixes offer enhanced protein stability and synergistic interfacial or textural properties that make them a flexible tool for food design. Fermentation offers important prospects for the nutritional and sensorial enhancement of animal/plant mixes, through the multi-criteria application of microbial consortia. Animal/plant mixes enable reduction in animal protein consumption while preserving amino acid and micronutrient intakes and sensory properties. However, their acceptability to consumers and society will also depend on controlled safety, especially regarding allergies or contaminants, on affordability, their degree of novelty or (ultra)processing, their actual environmental footprint and whether they meet consumer expectations for innovative foods in the transition towards greener diets.
The use of plant proteins to design colloidal food systems is a hot topic in the current context of the protein transition. However, replacing animal-derived proteins (in particular, dairy proteins) that have been traditionally used for this purpose by plant proteins is a challenge from various perspectives, and in particular, because of drastically different solubility and functionality. A possible route to mitigate these issues is to combine plant and dairy proteins, providing that their interactions can be understood from the molecular to the macroscopic scale. This review addresses the major advances that have occurred in the field of such blend-based systems, all the way from their behaviour in aqueous dispersions to their potential applications in gels, foams and emulsions.
The atomic force microscope (AFM) has opened access to the nanoscale observation of molecular and colloidal structures in aqueous media, and of their dynamics upon environmental changes. As a miniature force scanner, it furthermore allows the correlative mapping of mechanical properties at the nanoscale or precise indentation of individual structures. Soon after its invention in 1986, the AFM rapidly found increasing applications in soft matter physics, cellular biology, polymer science and microbiology. In spite of significant successes as early as the 90s, the growth of AFM application in the field of food science has been comparatively slower. This review points to the realizations and opportunities of AFM in showing the connections between the structural and mechanical properties of food's building blocks and of their assemblies. Possible transfers from other disciplines to food science are presented as suggestions for future applications.
The rheological properties and microstructure of dairy gels involve the connectivity between milk fat globules (MFG) and casein micelles that is affected by technological processes such as milk homogenization and heat treatment. The underlying mechanisms require further quantification of the interactions at the nanoscale level to be fully understood and controlled. In this study, we examined the adhesion of homogenized MFG to milk proteins and evaluated the role of ultra-high temperature (UHT) heat treatment and pH. The combination of physico-chemical analysis, rheology and microscopy observations at different scale levels associated to atomic force microscopy (AFM) force spectroscopy were used. AFM experiments performed at the particle scale level showed that adhesion of individual homogenized MFG to milk proteins (1) is increased upon acidification at pH 4.5: 1.4 fold for unheated samples and 3.5 fold for UHT samples, and (2) is enhanced by about 1.7 fold at pH 4.5 after UHT heat treatment of milk, from 176 pN to 296 pN, thanks to highly-reactive heat-denatured whey proteins located at the surface of MFG and caseins. The increased inter-particle adhesion forces accounted for more connected structures and stiffer UHT milk acid gels, compared to unheated-milk gels. Using a multiscale approach, this study showed that heat treatment of milk markedly affected the interactions occurring at the particle's surface level with consequences on the bulk structural and rheological properties of acid gels. Such findings will be useful for manufacturers to modulate the texture of fermented dairy products through the tailoring of heat-induced complexation of proteins and the connectivity of homogenized MFG with the protein network. This work will also contribute in a better understanding of the impact of process-induced changes on the digestibility and metabolic fate of proteins and lipids.
This study explores the production of polysaccharides (PS) in the strain Pf2289 of the food species Propionibacterium freudenreichii. Pf2289 presents characteristics atypical of the species: a molar-shaped morphotype upon plating, and cells strongly aggregative in liquid medium. When plating Pf2289, another morphotype was observed with a 4% frequency of appearance: round-shaped colonies, typical of the species. A clone was isolated, designated Pf456. No reversibility of Pf456 towards the molar-shaped morphotype was observed. Pf2289 was shown to produce a surface polysaccharide (PS) bound to the cell wall, mainly during the stationary growth phase. Meanwhile, Pf456 had lost the ability to produce the PS. AFM images of Pf2289 showed that entangled filaments spread over the whole surface of the bacteria, whereas Pf456 exhibited a smooth surface. Adhesion force maps, performed with concanavalin-A grafted probes, revealed twice as much adhesion of Pf2289 to concanavalin-A compared to Pf456. Furthermore, the length of PS molecules surrounding Pf2289 measured at least 7 μm, whereas it only reached 1 μm in Pf456. Finally, the presence of PS had a strong impact on adhesion properties: Pf2289 did not adhere to hydrophobic surfaces, whereas Pf456 showed strong adhesion.
Propionibacterium freudenreichii is a beneficial bacterium that modulates the gut microbiota, motility and inflammation. It is traditionally consumed within various fermented dairy products. Changes to consumer habits in the context of food transition are, however, driving the demand for non-dairy fermented foods, resulting in a considerable development of plant-based fermented products that require greater scientific knowledge. Fermented soymilks, in particular, offer an alternative source of live probiotics. While the adaptation of lactic acid bacteria (LAB) to such vegetable substrates is well documented, little is known about that of propionibacteria. We therefore investigated the adaptation of Propionibacterium freudenreichii to soymilk by comparison to cow's milk. P. freudenreichii grew in cow's milk but not in soymilk, but it did grow in soymilk when co-cultured with the lactic acid bacterium Lactobacillus plantarum. When grown in soymilk ultrafiltrate (SUF, the aqueous phase of soymilk), P. freudenreichii cells appeared thinner and rectangular-shaped, while they were thicker and more rounded in cow's milk utltrafiltrate (MUF, the aqueous phase of cow milk). The amount of extractable surface proteins (SlpA, SlpB, SlpD, SlpE) was furthermore reduced in SUF, when compared to MUF. This included the SlpB protein, previously shown to modulate adhesion and immunomodulation in P. freudenreichii. Tolerance toward an acid and toward a bile salts challenge were enhanced in SUF. By contrast, tolerance toward an oxidative and a thermal challenge were enhanced in MUF. A whole-cell proteomic approach further identified differential expression of 35 proteins involved in amino acid transport and metabolism (including amino acid dehydrogenase, amino acid transporter), 32 proteins involved in carbohydrate transport and metabolism (including glycosyltransferase, PTS), indicating metabolic adaptation to the substrate. The culture medium also modulated the amount of stress proteins involved in stress remediation: GroEL, OpuCA, CysK, DnaJ, GrpE, in line with the modulation of stress tolerance. Changing the fermented substrate may thus significantly affect the fermentative and probiotic properties of dairy propionibacteria. This needs to be considered when developing new fermented functional foods.