# Life cycle assessment of a semi-industrial infant milk formula powder and of a low-heat alternative process involving membrane filtration

Michèle Gaillard, Emma Saint-Preux, Amélie Deglaire, Emeline Goussé, Gaëlle Tanguy, Nadine Leconte, Geneviève Gésan-Guiziou, Fanny Guyomarc’h, Juliane Floury

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Michèle Gaillard, Emma Saint-Preux, Amélie Deglaire, Emeline Goussé, Gaëlle Tanguy, et al. Life cycle assessment of a semi-industrial infant milk formula powder and of a low-heat alternative process involving membrane filtration. Cleaner Environmental Systems, 2025, 17, pp.100278. 10.1016/j.cesys.2025.100278. hal-05178329

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# Life cycle assessment of a semi-industrial infant milk formula powder and of a low-heat alternative process involving membrane filtration

Michèle Gaillard, Emma Saint-Preux, Amélie Deglaire, Emeline Goussé, Gaelle Tanguy, Nadine Leconte, Geneviève Gésan-Guiziou, Fanny Guyomarc’h, Juliane Floury

INRAE, Institut Agro, UMR STLO, 35042, Rennes, France

## ARTICLE INFO

**Keywords:**

Infant milk formula

Eco-design

Microfiltration

Pasteurization

Processing

Life cycle assessment

## ABSTRACT

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.

## 1. Introduction

Although exclusive breastfeeding is recommended for infants throughout the first 6 months of life, only 56 % of them are still exclusively breastfed at the age of one month in France, 34 % at 2 months and 8 % at 6 months (Coulm, 2021; Salanave et al., 2024). There are also strong disparities between countries, varying from 26 % of exclusive breastfeeding at 6 months in North America up to 58 or 60 % in Eastern and Southern Africa or Asia (UNICEF, 2022). Globally, only 48 % of the world’s infants benefit from the WHO’s recommendations for breastfeeding, which has important consequences for both infants and mothers (Baker et al., 2023). Therefore, replacing breastmilk raises tremendous sustainability issues.

As substitutes to human milk, infant formulas (IF) are regulated mixtures of skimmed milk, mostly from bovine origin, with whey

proteins, fats, carbohydrates, minerals and vitamins, formulated to specifically meet the nutritional requirement of infants aged 0–6 months (European Union, 2016; UNICEF, World Health Organization, 2007). Classic infant formula production route starts with either liquid or dry milk, and involves the following series of unit operations: skimming, pasteurization, separation of casein and whey proteins, blending of these ingredients with lactose, concentration by vacuum evaporation, addition of vegetable and fish oils, homogenization and spray-drying. Throughout this process, the formula undergoes several heat treatments to ensure microbial safety of the final powder, which adversely affects its nutritional content and functional properties (Deglaire et al., 2023; Zhang et al., 2022). If pasteurization at 85 °C for 30 s is replaced by a 0.8-µm microfiltration at 50 °C, bacteria are removed while alleviating milk proteins’ heat-denaturation (Yu et al., 2021) and promoting the nitrogen digestibility and sensory properties of the formula (Calvez

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<footnote>* Corresponding author.
E-mail address: juliane.floury@institut-agro.fr (J. Floury).</footnote>
et al., 2024; Martin et al., 2024). Second to microbial safety and health concerns, ensuring the sustainability of IF supplies is crucial. Notably, the contribution of the dairy sector to the total greenhouse gases (GHG) emissions is 3–4 % worldwide (FAO, 2010) and 6–7 % in France (France Terre de Lait, 2022). In this respect, microfiltration has also been proposed as a means to reduce the carbon footprint of dairy powders (France et al., 2021).

Table 1 highlights the range of environmental impacts associated with these products and illustrates the limitations of published studies. The carbon footprint of cradle-to-gate production of 1 kg of IF powder

ranges from 7.1 to 11 kg CO₂ eq per kg in France, New Zealand, USA or Brazil (Cadwell et al., 2020; Karlsson et al., 2019). However, most life cycle inventories used average recipes of IFs, where ingredients and processing operations (when considered) were database proxies, with great uncertainty. Finally, only one is a multicriteria life cycle assessment (Andresen et al., 2022).

The objective of this study is therefore to support the eco-design of IF by performing the first complete life cycle assessment of their production, involving extensive primary data for both the several milk ingredients and processing unit operations at semi-industrial scale. The

<caption>**Table 1**</caption>

Summary of published studies on the environmental impact assessment (using single-criterion or multi-criteria methods) of infant formula and bovine milk powder production.

<table><thead><tr><th>Product</th><th>Environmental assessment method</th><th>Carbon footprint (kg CO<sub>2</sub> eq)</th><th>Cumulative Energy (MJ)</th><th>Functional Unit (UF)</th><th>Data Sources</th><th>Geographical perimeter</th><th>Scope</th><th>Remark</th><th>Reference</th></tr></thead><tbody><tr><td>Infant Formula</td><td>LCA (6 impact categories)</td><td>12.65</td><td>/</td><td>1 kg powdered infant formula at retail</td><td>Data from Karlsson et al. (2019)</td><td>Norway</td><td>Cradle-to-grave, Breastfeeding comparison</td><td>Whey proteins are co-products from cheese industry</td><td>Andresen et al. (2022)</td></tr><tr><td>Infant Formula</td><td>LCA (1 impact category)</td><td>7.1–11</td><td>/</td><td>1 kg of IF powder with an energy content of 21.7 kJ/g</td><td>Data from industry</td><td>New Zealand, USA, Brazil, and France</td><td>Cradle-to-gate, packaging and transport post factory included, Breastfeeding comparison</td><td>Minor ingredients are not included (vitamins and minerals)</td><td>Karlsson et al. (2019)</td></tr><tr><td>Infant Formula</td><td>LCA (1 impact category)</td><td>8.49</td><td>/</td><td>1 kg of standard infant milk powder</td><td>Data from Literature, Euromonitor International, FAO</td><td>North America</td><td>Cradle-to-gate</td><td>/</td><td>Cadwell et al. (2020)</td></tr><tr><td>Infant Formula</td><td>LCA (1 impact category)</td><td>3.95</td><td>/</td><td>1 kg of infant milk powder</td><td>Euromonitor International Baby Food country report</td><td>Asia</td><td>Cradle-to-gate</td><td>No consideration of energy needed for mixing milk and ingredients, Post-processing stages not included</td><td>Dadhich et al. (2021)</td></tr><tr><td>Non-fat Milk powder</td><td>LCA (1 impact category) + Energy consumption</td><td>1.3–1.4</td><td>23.6–26.2</td><td>1 kg of unpacked skimmed milk powder</td><td>Data collected from measures, Data from literature</td><td>Greece</td><td>Gate-to-gate; transport of raw milk included; Reverse osmosis production plant</td><td>Raw milk production is not included</td><td>Krokida et al. (2016)</td></tr><tr><td>Milk powder</td><td>LCA (4 impact categories)</td><td>1.32</td><td>/</td><td>1 kg of milk powder</td><td>Data from milk powder production in a private company (confidential name) and product distribution</td><td>Indonesia</td><td>Cradle-to-gate</td><td>/</td><td>Allia et al. (2018)</td></tr><tr><td>Milk powder</td><td>LCA (6 impact categories)</td><td>1.482</td><td>21.75</td><td>1 kg of milk powder</td><td>Data collected from five dairy processing factories of the Republic of Ireland</td><td>Ireland</td><td>Gate-to-gate</td><td>Farm milk production is not included</td><td>Finnegan et al. (2017)</td></tr><tr><td>Fat-enriched milk powder (vegetable oils)</td><td>LCA (1 impact category) + Energy consumption</td><td>1.088</td><td>16.67</td><td>1 kg of fat-enriched milk powder</td><td>Data collected from four Irish companies</td><td>Ireland</td><td>Gate-to-gate</td><td>Raw milk and vegetable oils are not included</td><td>Finnegan et al. (2017)</td></tr><tr><td>Milk powder</td><td>LCA (1 impact category) + Energy consumption</td><td>1.4–1.7</td><td>24,57</td><td>1 kg of dry matter</td><td>Data collected from four Irish companies</td><td>Ireland</td><td>Gate-to-gate</td><td>Farm milk production is not included</td><td>Yan et Holden (2018)</td></tr><tr><td>Milk powder</td><td>LCA (1 impact category)</td><td>7.4</td><td>/</td><td>1 kg of milk powder</td><td>Industrial data (Arla Foods)</td><td>Denmark</td><td>Cradle-to-grave</td><td>/</td><td>Flysjö et al. (2014)</td></tr><tr><td>Milk powder</td><td>LCA (1 impact category)</td><td>10.1</td><td>/</td><td>1 kg of milk powder</td><td>/</td><td>Canada</td><td>Cradle-to-gate</td><td>The on-farm part of the model is the Unified Livestock Industry and Crop Emissions Estimation System (ULICEES). Off-farm GHG emissions were estimated using the Canadian Food Carbon Footprint calculator, (cafoo)2-milk.</td><td>Vergé et al. (2013)</td></tr></tbody></table>
“classic” route, where extensive heat treatments are used, is compared with a so-called “alternative” route, where the first pasteurization is replaced by microfiltration. Hot-spots are identified and sensitivity analyses are used to further help identify actionable levers of eco-design at the processing level.

## 2. Materials and methods

### 2.1. Goal and scope

The goal of this study is to compare the potential environmental impacts of two processing routes to produce infant formula milk powder, using the approach of attributional life cycle assessment in compliance with ISO 14 040:2006 standards (ISO 14040, 2006). The scope is that of typical semi-industrial dairy plant in France, represented by the STLO Dairy Platform and the semi-industrial spray-drying facility BIONOV SA (both in Rennes, France). Life cycle inventory data were retrieved from previous research projects, namely the SILL-INRAE 2016/0537 CIFRE partnership (2016–2019), which reported the classic production route, and data from the Carnot Qualiment NativiF project (2017–2019), which reported the alternative production route. The whey protein isolate (WPI; liquid or dry) and the lactose ingredient were retrieved from (Guyomarc'h et al., 2024a). With this, the scope is that of comprehensive primary data of the two routes, down to single unit operations, and even down to splitting each unit operation into its ramping-up, full regime and cleaning phases.

### 2.2. System description: the classic vs alternative infant milk powder production routes

Fig. 1 shows a diagram of the infant formula production process, highlighting in the two blue frames the key differences between the classic and alternative processing routes. In the classic route, raw milk is skimmed at 50 °C then blended at the same temperature with the non-fat ingredients, i.e. the dry WPI, liquid lactose and water as to reach in blend 1 the regulated casein-to-whey protein and protein-to-lactose

ratios of infant formula milks. At this stage, blend 1 is a 20 % w/w dry matter dispersion. It is sanitized using pasteurization at 85 °C for 30 s, then concentrated by vacuum evaporation, blended with oils to form blend 2, heat-treated again through final pasteurization, homogenized and spray-dried (Fig. 1; Le Roux et al., 2020).

In the alternative route, the skimmed milk was subjected to microfiltration at 50 °C up to a volume concentration factor of 20 using a 0.8-µm pore size ceramic membrane. The retentate containing bacteria was discarded. The WPI and lactose were subsequently incorporated into the microfiltration permeate, leading to a 24 % dry matter dispersion. The use of liquid WPI instead of dry WPI and of microfiltration instead of pasteurization at 85 °C minimized thermal processing of the milk proteins (Fig. 1; Yu et al., 2021).

Both routes proceeded to a concentration step using vacuum evaporation in a two-effect falling-film evaporator, reaching 45 % and 43 % dry matter for the classic and alternative routes, respectively. A vegetable oil blend was then added to the concentrate at 60 °C using a two-stage homogenizer at 14 and 4 MPa. The resulting 51 % dry matter fat-reconstituted formula then underwent final pasteurization at 75 °C for 2 min, followed by spray drying to achieve a final infant formula milk powder with a dry matter content of 97 %. A single BIONOV production batch, lasting half a day, typically yielded 62.5 kg of infant formula powder meeting the required quality standards. The reference flows and ingredients' dry matter content are detailed in Table 2 and will serve for scaling results to the functional unit.

### 2.3. Functional unit and system boundary

The functional unit (FU) chosen for this study is 1 kg of unpackaged infant formula milk powder produced at a semi-industrial scale. This FU is the same for classic and alternative production routes to ensure a fair comparison of their potential environmental impacts. A farm-to-gate perspective was adopted for this analysis. The system boundary encompasses the following steps: agricultural production of the ingredients, transportation of raw milk, each of the unit operation at the processing stage from skimming to spray-drying, individual or in-place

<figure><img src="image_4.png" /><figcaption>Fig. 1. Cradle-to-gate system boundaries (dotted lines) with unit operations (grey) and raw materials (blue) for the classic or alternative production routes of Infant milk Formula powder (in green). Downstream unit operations after processing (in yellow) are excluded from the system.</figcaption></figure>
<caption>**Table 2**</caption>

Ingredient mass and dry matter content for 62.5 kg of infant formula milk powder for the classic or alternative production route.

<table><thead><tr><th rowspan="2">Raw materials</th><th colspan="2">Classic route</th><th colspan="2">Alternative route</th></tr><tr><th>Mass (kg)</th><th>Dry matter content (w/w%)</th><th>Mass (kg)</th><th>Dry matter content (w/w%)</th></tr></thead><tbody><tr><td>Raw milk</td><td>179.3</td><td>13 %</td><td>210.7</td><td>13 %</td></tr><tr><td>Whey Protein Isolate (WPI)</td><td>6.0 (powder)</td><td>95 %</td><td>21.9 (liquid)</td><td>27 %</td></tr><tr><td>Liquid lactose</td><td>90.8</td><td>50 %</td><td>92.5</td><td>50 %</td></tr><tr><td>Vegetable oil blend</td><td>21.2</td><td>99.9 %</td><td>26.5</td><td>99.9 %</td></tr><tr><td>Water</td><td>108.5</td><td>/</td><td>/</td><td>/</td></tr><tr><td>Maltodextrin</td><td>9.7</td><td>95 %</td><td>/</td><td>/</td></tr><tr><td>Minerals</td><td>/</td><td>/</td><td>1.9</td><td>100 %</td></tr></tbody></table>

cleaning of each unit operation as well as the end-of-life treatment of biowastes or plastic and metal disposals (Fig. 1). Downstream processes, i.e. packaging, transportation, retail, consumption and product end-of-life were excluded from the system boundary, as they were considered to be consistent across both production routes and unlikely to significantly influence the comparison. Fish oils, maltodextrin, micronutrients (each <2.5 % w/w dry matter in the formula), and transportation of the whey protein isolate (WPI), lactose and oil blends were excluded from the system boundary due to lack of data.

## 2.4. Life cycle inventory (LCI)

### 2.4.1. Raw materials

The primary objective of this study was to compare the two infant formula production routes, focusing on the processes and their unit operations. The classic and alternative IF productions respectively described in Le Roux et al. (2020) and Yu et al. (2021) were therefore adapted to involve the same ingredients. In essence, common industrial practice as targeted by Le Roux et al. (2020) is to use lactose, whey protein and skim milk in powder form, to be blended into water and/or liquid milk. To maintain consistency in the formulation, skim milk and lactose were introduced in the liquid form in both production routes, as it is a requirement of the alternative route. This adaptation prevented upstream processes, such as concentration and spray-drying of these ingredients, to generate excessive discrepancies in the respective environmental impacts of the two IF powders, without any link with the two production routes. The whey protein ingredient, usually a concentrated by-product of cheese-making in classic routes, was changed to the same low-heat whey protein isolate (WPI) as in the alternative route. However, this WPI was considered in a powder form in the classic route and in a liquid form in the alternative route, and the contribution of the dry vs liquid form of WPI in the environmental impacts of the classic IF was the subject of a specific sensitivity analysis (see below). The liquid low-heat WPI was obtained by low temperature (<10 °C) microfiltration of skim milk with a 0.1-µm pore size ceramic membrane, followed by ultrafiltration and diafiltration (Gésan-Guiziou et al., 2019). The corresponding life cycle inventory is available in Guyomarc'h et al. (2024a). The dry WPI for the classic route was obtained by applying concentration and spray-drying to the same liquid low-heat WPI, using the spray-drying data of similar protein ingredients as proxies (Guyomarc'h et al., 2024a; Schuck et al., 2015). Whenever formulation changes implied variation of the volume to be treated by any unit operation, the necessary operating times and the corresponding energy consumptions were recalculated. A detailed description of the classic and alternative life cycle inventories is provided in the associated data paper (Gaillard et al.,.). Inventory data for raw milk and vegetable oils were obtained from the Agribalyse 3.1 (Cornelus et al., 2024) and Ecoinvent 3.10 databases. The specific vegetable oil blend involved in both initial production routes, which included coconut, sunflower,

rapeseed, and palm oils, was not available in these databases. A blend of sunflower, linseed and rapeseed oils, as documented in the Agribalyse database (Cornelus et al., 2024), was employed as a proxy. It is noteworthy that raw milk was skimmed to yield both skimmed milk and cream as co-products. A dry matter allocation of the environmental impacts was implemented, attributing 70 % of the impacts to skimmed milk and 30 % to cream (Guyomarc'h et al., 2024a).

### 2.4.2. Processing

Each unit operation was divided in three distinct phases: ramping-up (transient), full operational regime (steady state) and cleaning. The transient phase is expected to be energy-intensive, as equipment operates at full power to heat fluids and reach pump flow rates. Meanwhile, the cleaning phase is likely to involve significant water and chemical consumption. Given the intermittent nature of semi-industrial production, the transient and cleaning phases both constituted a significant part of the total unit operation time, and this approach enabled a detailed analysis of the process' performance. Noteworthy, the BIONOV SA facility exclusively uses electrical energy, in contrast to industrial dairies which primarily use natural gas for their thermal needs.

Briefly, a comprehensive mass balance and processing schedule were established for each unit operation based on data from Le Roux et al. (2020) and Yu et al. (2021). Measured material losses, consumable use and equipment lifetime, along with expert estimations, were incorporated into the analysis. Energy consumptions were derived from experimental measurements, rated power of the machines, expert interviews, and calculations using classical process engineering formula of energy transfer and literature-based values of heat or evaporation capacity (Jeantet et al., 2011; Schuck et al., 2015). Water consumption and discharge, including detergent solutions, were quantified through on-site measurements, encompassing water used for process cooling, pumping, and cleaning. More details are available in the associated data paper (Gaillard et al.,.). The inventory data were implemented into the INRAE-CIRAD MEANS-InOut software (https://means.inrae.fr/eng/e mc-tools/lca-inventory-with-means-inout) to check for mass balances and completeness prior to use in life cycle assessment.

### 2.4.3. Other reference flows

Only the transport of raw milk was considered; it came from a 30-km distant dairy plant in Montauban-de-Bretagne (France) and was transported in an unrefrigerated van. A share of the materials and metals involved in the processing equipment was attributed to the functional unit *prorata temporis* of their total depreciation lifetime. Polymers and metals were recycled. The microfiltration retentate containing bacteria as well as the output cleaning water were considered as biowastes and regarded as treated in a local public waste water treatment plant.
## 2.5. Environmental impact assessment

The Environmental Footprint 3.0 method (EF 3.0) V1.03 (Fazio et al., 2018) was selected for this study as adapted to SimaPro 9.5.0.1 software (PRé Sustainability B.V., Amersfoort, The Netherlands). All the 16 midpoint impact categories were calculated and results are available in the associated data paper (Gaillard et al.,). From these 16 midpoint impact categories, 8 are particularly relevant to food systems: climate change; use of fossil resource; ionizing radiation (in relation to the French electricity mix); acidification; marine eutrophication; freshwater ecotoxicity; land use and water use.

To assess the robustness of the LCA results, the environmental impacts of 1 kg IF were calculated for both routes using other characterization methods, namely ReCiPe v1.1 midpoint Hierarchist perspective (Huijbregts et al., 2020), LC-Impact (Verones et al., 2020), CML-IA baseline v3.08 (CML-IA Characterisation Factors, 2016) and Impact World + Midpoint v1.02 (Bulle et al., 2019). Only the overall results of the EF and ReCiPe characterization methods are reported and analysed in the present paper. Results of the two IF's environmental impacts as calculated with the other characterization methods are available in Gaillard et al.,

## 2.6. Uncertainty

The distribution of input data was assumed to be log-normal and its quality, represented by the square of its geometrical standard deviation, was determined using a Pedigree matrix (values are provided in Gaillard et al.,. A Monte Carlo simulation with 1000 iterations was then conducted for each route. A second Monte Carlo simulation was finally performed to compare the two routes, also with 1000 iterations.

## 2.7. Sensitivity analyses

Two sensitivity analyses were conducted to closely investigate the influence of water content on the overall environmental impacts of the classic IF production route, to identify other levers for eco-design alongside the substitution of pasteurization by microfiltration. In the first sensitivity analysis, the water input in blend 1 was reduced, so that its final dry matter content (DM) matched that of the alternative route at the evaporator inlet (24 % w/w instead of 20 % in the initial classic route). This simulated process was named the “DM Adjusted Classic route”.

A second sensitivity analysis was conducted to evaluate the influence

of the physical state of the WPI ingredient on the environmental impacts of the classic route. For this purpose, the input WPI was modified from powder to liquid state and the water initially used to dilute the WPI powder was removed. As a result of the dry matter difference between the diluted WPI powder and the liquid WPI, the final dry matter of blend 1 reached 26.7 % w/w at the evaporator inlet. This simulated process was named the “DM and WPI Adjusted Classic route”. In both simulated processes, changes in the final dry matter content (and volume) of blend 1 required corrections of the duration and energy consumptions of the concentration by vacuum evaporation step, accessible in Gaillard et al.,

## 3. Results and discussion

### 3.1. Environmental impacts of the classic vs alternative infant formula production routes

The potential environmental impacts associated with the farm-to-gate production of 1 kg of infant formula using either the classic or alternative production route are shown in Table 3 for the 8 selected impact categories. At largest, the alternative route exhibited only slightly over 12 % more impact than the classic route on land use, no

<figure><img src="image_5.png" /><figcaption>Fig. 2. Comparative Monte Carlo simulation of eight potential impact categories between the classic (B) or alternative (A) production routes of 1 kg of Infant milk Formula powder, calculated by the EF 3.0 characterization method (n = 1000). If A > B then it can be concluded that the alternative route has a higher environmental impact than classic route on the considered midpoint impact category.</figcaption></figure>

### Table 3

Absolute values and relative differences between the potential environmental impacts of 1 kg of infant formula produced at semi-industrial scale by the classic or alternative route using 2 characterization methods: EF 3.0 and ReCiPe 2016 (uncertainties were calculated using Monte Carlo simulation with n = 1000).

<table><thead><tr><th rowspan="2">Impact category</th><th colspan="4">EF 3.0 Method</th><th colspan="4">ReCiPe 2016 Method</th></tr><tr><th>Unit</th><th>Classic route (mean ± SD)</th><th>Alternative route (mean ± SD)</th><th>Difference (%)</th><th>Unit</th><th>Classic route (mean ± SD)</th><th>Alternative route (mean ± SD)</th><th>Difference (%)</th></tr></thead><tbody><tr><td>Climate change</td><td>kg CO<sub>2</sub>eq</td><td>10.45 ± 0.48</td><td>11.14 ± 0.48</td><td>6.6 %</td><td>DALY</td><td>9.58 × 10<sup>-6</sup></td><td>1.02 × 10<sup>-5</sup></td><td>6.6 %</td></tr><tr><td>Resource use, fossils</td><td>MJ</td><td>204.16 ± 2.36</td><td>195.65 ± 1.73</td><td>-4.2 %</td><td>USD 2013</td><td>3.4 × 10<sup>-1</sup></td><td>3.4 × 10<sup>-1</sup></td><td>1.5 %</td></tr><tr><td>Ionizing radiation</td><td>kBq U-235eq</td><td>8.15 ± 0.084</td><td>7.71 ± 0.05</td><td>-5.3 %</td><td>DALY</td><td>7.15 × 10<sup>-8</sup></td><td>6.76 × 10<sup>-8</sup></td><td>-5.4 %</td></tr><tr><td>Acidification</td><td>kg SO<sub>2</sub>eq</td><td>0.106 ± 0.006</td><td>0.114 ± 0.006</td><td>8.3 %</td><td>Species. yr</td><td>1.45 × 10<sup>-8</sup></td><td>1.57 × 10<sup>-8</sup></td><td>8.2 %</td></tr><tr><td>Eutrophication marine</td><td>kg Neq</td><td>0.038 ± 0.003</td><td>0.042 ± 0.003</td><td>11.1 %</td><td>Species. yr</td><td>1.50 × 10<sup>-11</sup></td><td>1.69 × 10<sup>-11</sup></td><td>12.1 %</td></tr><tr><td>Ecotoxicity, freshwater</td><td>CTUe</td><td>250.56 ± 14.36</td><td>270.6 ± 14.1</td><td>8 %</td><td>Species. yr</td><td>3.71 × 10<sup>-10</sup></td><td>3.44 × 10<sup>-10</sup></td><td>-7.0 %</td></tr><tr><td>Land use</td><td>Pt</td><td>547 ± 38</td><td>613 ± 38</td><td>12.1 %</td><td>Species. yr</td><td>9.58 × 10<sup>-8</sup></td><td>1.07 × 10<sup>-7</sup></td><td>12.2 %</td></tr><tr><td>Water use</td><td>m<sup>3</sup> depriv.</td><td>5.05 ± 0.22</td><td>5.06 ± 0.22</td><td>0.1 %</td><td>/</td><td>/</td><td>/</td><td>/</td></tr><tr><td>Water use, Human Health</td><td>/</td><td>/</td><td>/</td><td>/</td><td>DALY</td><td>2.44 × 10<sup>-7</sup></td><td>2.37 × 10<sup>-7</sup></td><td>-3.4 %</td></tr></tbody></table>
matter the characterization method. Differences are below 10 % for climate change, fossil resource depletion, ionizing radiation, acidification, ecotoxicity, and water use. Except for both impact categories related to energy consumption (use of fossil resources and emission of ionizing radiations), the alternative route is therefore slightly more impacting than the classic route, mainly as a result of larger requirements of raw milk for microfiltration implementation.

Monte Carlo simulation on the EF 3.0 results indicated that the classic route exhibited higher impacts than the alternative route for fossil resource depletion and ionizing radiation with 100 % likelihood. In contrast, the alternative route exhibited higher impacts than the classic route in all 6 remaining impact categories, with 90 % likelihood (Fig. 2). The 'water use' category showed minimal variation between the two routes, with the alternative route exceeding the classic route in only 61 % of cases. Although differences seemed robust, it can be concluded from this comparison of the two production routes that neither route demonstrated significantly higher overall environmental impacts than the other, regardless of the considered impact category. In other words, replacement of pasteurization by microfiltration did not reduce the overall environmental impacts of IF production and/or it can enhance the nutritional quality of the product with only little increase of the environmental burden.

These results align with existing environmental impact assessments of infant formula, notably complementing previous work by Andresen et al. (2022); Cadwell et al. (2020) and Karlsson et al. (2019). The classic and alternative IF yielded respective carbon footprints of 10.45 kg CO₂ eq and 11.14 kg CO₂ eq per kg of IF. (Karlsson et al. (2019) reported a lower carbon footprint of 7.58 kg CO₂ eq/kg IF, probably as a result of assessing an optimized industrial scale instead of a semi-industrial production scale, while Cadwell et al. (2020) and Dadhich et al.

(2021) used simplified life cycle inventory with only emission factors for the input ingredients, not the skimming to drying process line, and therefore could report even lower values (Table 1).

## 3.2. Contribution analysis

Expectedly, agricultural production of raw materials and industrial processing emerged as the most significant contributors across all impact categories, leaving less than 2 % of the total impacts to transport or waste treatment (Fig. 3A). Therefore, the latter will not be further discussed in this article. Notably, the ingredients such as milk and vegetable oils contributed to more than 80 % of the "climate change" impact category. Those ingredients were also dominant contributors to acidification, marine eutrophication, freshwater ecotoxicity, land use and water use, i.e. to all impact categories that are closely linked to agricultural practices and especially livestock breeding (Milani et al., 2011; Poore et Nemecek, 2018). Similar findings were reported by (Andresen et al., 2022), where raw material production accounted for 48 %–95 % of environmental impacts, depending on the category. Especially, the classic or alternative production route respectively required 2.9 or 3.4 kg of raw milk, to produce the casein fraction of 1 kg of infant formula powder (Table 2), which mainly drove the slightly higher environmental impacts of the alternative IF on agriculture-related categories. This resulted from filling-up and stabilizing the microfiltration operation then discarding the bacterial retentate i.e. a fraction of the total skim milk.

The processing stage was the second-largest contributor to the environmental impacts of IF production. It accounted for less than 16 % of the impacts in categories related to agricultural activities (Fig. 3A), but contributed for a significant 45 % to water use and to over 85 % in

<figure><img src="image_6.png" /><figcaption>**Fig. 3.** Absolute values of (A) the respective contribution of agricultural production of raw materials, transport, processing and waste-treatment to the environmental impacts of 1 kg Infant milk Formula powder manufactured using the classic (in blue) or alternative route (in yellow) and for the selected midpoint environmental impact categories; and (B) the respective contributions of individual unit operations at the processing stage, for the same functional unit, the same impact categories and with the same colour code. The transient, production and cleaning phases are aggregated for each unit operation.</figcaption></figure>
<figure><img src="image_7.png" /><figcaption>**Fig. 4.** Contributions, in absolute kWh values, of each unit operation as split into its transient, steady-state and cleaning phases, to the total energy consumption of both the classic or alternative infant formula production routes down to the functional unit of 1 kg Infant milk Formula powder.</figcaption></figure>

impact categories associated with energy consumption, such as the use of fossil resources and the emission of ionizing radiations, the latter being closely linked to the share of nuclear power in France's electricity mix. At the processing stage, the classic production route exhibited 3-4 % higher environmental impacts to climate change, acidification and land use, and 6-7 % higher impacts on fossil resource use, ionizing radiation and water use than the alternative route. As later evidenced by sensitivity analyses, this difference is mainly due to the larger volume and lower dry matter content of the classic recipe (Table 2), hence greater time and energy consumptions for processing. Notably, the majority of environmental impacts were attributed to concentration by vacuum evaporation and spray-drying, which respectively contributed 26-42 % and 9-39 % of the total environmental impacts of the processing stage across all midpoint impact categories (Fig. 3B).

**Fig. 4.** based on LCI data, further illustrates the distribution of energy consumption across the different production phases—transient, steady-state, and cleaning—for all unit operations in both the classic and alternative routes. Concentration by vacuum evaporation (in blue) and spray-drying (in purple) together accounted for roughly 80 % of the total energy consumed during production, aligning with previously reported figures for milk powder production (Schuck et al., 2015). This high energy consumption is primarily due to the energy-intensive phase change of water into vapor. A significant additional contribution came from the two blending operations (Figs. 3B and 4), which required substantial electricity to ensure effective mixing and heat energy to maintain the product at 50 °C for up to 90 min per batch. Although the substitution of pasteurization of blend 1 by microfiltration was the major point of the alternative process, neither one nor the other

<figure><img src="image_8.png" /><figcaption>**Fig. 5.** Potential environmental impacts of the transient step (in dashed grey), the steady-state production step (in orange) and the cleaning step (in blue) of the pasteurization and microfiltration unit operations used for the classic or the alternative route, respectively, for the selected 8 impact categories and for the production of 1 kg Infant milk Formula powder.</figcaption></figure>
appeared as a significant contributor to the overall environmental im-
pacts of IF production (see also Fig. 3). Pasteurization expectedly
consumed energy during steady-state production, while microfiltration
rather consumed energy during cleaning (Fig. 4).

3.3. Comparison of environmental impacts of microfiltration and
pasteurization operation units

While it did not show superior environmental performance, the
alternative route however minimises heat-induced denaturation of milk
proteins with the use of microfiltration. Therefore, it is essential to
compare the environmental implications of substituting traditional
pasteurization with microfiltration used for the removal of bacteria.

This closer insight on the sanitation step showed that microfiltration
exhibited higher potential environmental impacts on land, water and
fossil resource uses, on water ecotoxicity, on ionizing radiation and up to
1.75-time greater impacts on marine eutrophication (Fig. 5). In contrast,
the impacts on climate change and acidification were similar for both
routes. Importantly, the cleaning phase accounted for the 81–84 % of the
potential environmental impact of microfiltration, due to the extensive
rinsing required to prevent membrane fouling (Guyomarc'h et al.,
2024b). Meanwhile, the steady-state and cleaning steps of the pasteur-
ization unit contributed most significantly to the environmental impacts
of the classic sanitation procedure, with the transient step contributing
much less (Fig. 5). Of course, different conclusions could be reached if
microfiltration was compared to more intensive heat loads, as were for
instance tested by Yu et al. (2021) or as could occur in industrial context
(Le Roux et al., 2020). On an industrial scale, cleaning is most likely to
rely on cleaning-in-place systems to minimise water and pollutant use
(e.g. use of recirculating solutions, in-situ nozzles, etc.). The steady-state
phase also tends to extend beyond a single production day, particularly
in continuous production with 3 × 8h shifts, thereby reducing the
relative impact of the transient and cleaning phases. In the present
study, the microfiltration process had a lower environmental impact
during the steady state phase than the pasteurization process (Fig. 5).
Therefore, optimizing the cleaning process could improve the overall
environmental performance of microfiltration and make it competitive
with pasteurization. Overall, this study highlights the challenge of
comparing or extrapolating the environmental impacts of manufactured
goods across different production scales. It emphasises that some envi-
ronmental costs remain fixed within system boundaries regardless of the

number of functional units produced, while others scale directly with
production volume.

3.4. Sensitivity analysis to dry matter content of input ingredients and
possible sustainable design pathways to reduce IF environmental footprint

While replacing pasteurization by microfiltration did not appear as a
relevant lever for eco-design, at least based on a functional unit of mass,
the presented results suggested that minimizing the amount of water to
be evaporated during concentration and spray-drying will reduce
energy-related environmental impacts. In a first sensitivity analysis
called the “DM adjusted classic route”, blend 1 recipe was adjusted as to
reach 24 % final dry matter instead of 20 %. Furthermore, it was hy-
pothesized that extra environmental impacts could be avoided if the WPI
ingredient was input in the liquid form instead of having been dried
itself prior to rehydration and re-drying of blend 1. The final DM of
blend 1 occurred to reach 26.7 %. This second sensitivity analysis was
called the “DM and WPI adjusted classic route”.

Both sensitivity analyses confirmed that optimizing the DM content
of the infant formula blend 1 using either less water and/or a concen-
trated liquid WPI solution led to the decrease of the potential environ-
mental impacts of 1 kg IF across all the 8 considered midpoint
environmental impact categories, especially for the energy-related use
of fossil resources and ionizing radiation where cuts could reach up to
8.2 and 6.2 %, respectively (Fig. 6). These results were directly attrib-
utable to a reduced volume and reduced water content, hence a reduced
energy consumption for blending and evaporation. Water use was also
decreased by 4.2 %, which can be related to the lower water input using
a concentrated WPI solution, but also the lower water quantity needed
for cooling equipment during processing stage (such as pumps for
example) as batch duration is reduced.

In order to confirm these conclusions, additional LCA simulations
should however be performed in order to evaluate the impacts of
different storage and distribution methods of the WPI, lactose and milk
ingredients in a (concentrated or not) liquid instead of a powder form.
Indeed, it is recognized that the storage of liquid ingredients has two
major disadvantages: its larger volume for both stockage and trans-
portation and the need to refrigerate these ingredients to avoid bacterial
growth. Transporting milk powder has for instance lower environmental
impacts than transporting sterilized concentrated milk (Depping et al.,
2017). Unfortunately, no data was available at the time of the research

<figure><img src="image_9.png" /><figcaption>**Fig. 6.** Calculated cuts of potential environmental impacts of the production of 1 kg Infant milk Formula powder by the classic route, using the “Dry-matter adjusted” or the “Dry-matter and WPI adjusted” sensitivity analysis scenario. The results are expressed in % variation for the 8 selected impact categories, relative to the classic route (20 %DM) which is set at 0.</figcaption></figure>
to include refrigerated storage and transport into the LCI. Meanwhile, Fig. 6 shows that optimizing the amount of water incorporated into blend 1 in order to disperse the dried ingredients is a readily accessible lever for eco-design.

## 4. Conclusion

This study conducted a comparative Life Cycle Assessment (LCA) of two infant formula production routes at a semi-industrial scale: the classic pasteurization-based route and an alternative route employing membrane microfiltration for the removal of bacteria. The primary objective was to assess the environmental sustainability benefits of the alternative method relative to the classic approach. This report provides valuable insights on the environmental performance of IF production, down to each operation unit, and even down to the relative impacts of transient, steady-state and cleaning stages, which should allow comparison with industrial processes where the transient phase is marginal.

While the alternative route demonstrated reduced energy consumption for heating, it required greater amounts of milk and water, resulting in overall environmental impacts comparable to those of the classic route. Based on the functional unit of 1 kg of unpackaged infant formula powder (IF), the alternative route cannot currently be classified as an eco-designed process. However, it is noteworthy that the alternative route did not exacerbate environmental impacts comparatively to the classical route. Moreover, if the nutritional quality of proteins could be incorporated into the functional unit, the alternative process might potentially be regarded as a more sustainable option.

In conclusion, the detailed examination of the two infant formula production routes, along with variations of the classic route, provided three main eco-design strategies to reduce the potential environmental impacts of infant formula milk powders: 1) Minimizing raw milk usage by integrating liquid or concentrated dairy co-products from on-site processes (e.g., within the dairy factory) to reduce storage and/or transport requirements and associated emissions. 2) Enhancing dry-matter content at the inlet of the concentration by vacuum evaporation unit to lower energy demands during subsequent processing. 3) Optimizing the microfiltration process by increasing the volume reduction factor, minimizing fouling, and implementing less environmentally impactful cleaning protocols.

These findings provide actionable levers for improving the sustainability of infant formula production while maintaining product quality and safety. Further research is needed to explore the potential benefits of combining these strategies with innovative formulations and large-scale industrial applications.

### CRediT authorship contribution statement

**Michèle Gaillard:** Writing – original draft, Methodology, Investigation, Data curation, Conceptualization. **Emma Saint-Preux:** Methodology, Investigation, Data curation, Conceptualization. **Amélie Deglaire:** Writing – review & editing, Resources, Investigation, Funding acquisition, Conceptualization. **Emeline Gousse:** Writing – review & editing, Resources, Investigation, Conceptualization. **Gaelle Tanguy:** Writing – review & editing, Resources, Investigation, Conceptualization. **Nadine Leconte:** Writing – review & editing, Resources, Investigation, Conceptualization. **Geneviève Gésan-Guiziou:** Writing – review & editing, Resources, Investigation, Funding acquisition, Conceptualization. **Fanny Guyomarc'h:** Writing – review & editing, Supervision, Methodology, Data curation, Conceptualization. **Juliane Floury:** Writing – review & editing, Supervision, Resources, Methodology, Investigation, Data curation, Conceptualization.

### Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence

the work reported in this paper.

### Acknowledgements

Data used in this work originated from three previous projects, one funded by the French National Research Agency (ANR) under the grant ANR-06-PNRA-015 "Eco-design of membrane processes for obtaining proteins with target function(s)" (ECOPROM), one funded by the National Agency for Research and Technology (ANRT) under the grant "CIFRE 2016/0537" and one funded by the Carnot institute Qualiment under the grant "NativIF". The authors would like to acknowledge INRAE Dairy Platform (IE-STLO, INRAE, 2018. Milk and Egg Technology facility, DOI: 10.15454/1.557240525786479E12) and BIONOV SA where all experiments were conducted. The authors are also much grateful to L. Le Roux (SILL Enterprises, Plouvien, France), R. Jeantet (STLO, INRAE, Institut Agro, Rennes, France) and G. Le Maout (BIONOV SA, Rennes, France) for their expertise.

### Data availability

I have shared the link to my data at the Attach File step.

Life cycle data of classic and low-heat processing routes for infant formula powder production (Original data) (Dataverse).

### References

Andresen, E.C., Hjelkrem, A.-G.R., Bakken, A.K., Andersen, L.F., 2022. Environmental impact of feeding with infant formula in comparison with breastfeeding. Int. J. Environ. Res. Publ. Health 19, 6397. https://doi.org/10.3390/ijerph19116397.

Baker, P., Smith, J.P.,ardea, A., Grummer-Strawn, L.M., Wood, B., Sen, G., Hastings, G., Pérez-Escamilla, R., Ling, C.Y., Rollins, N., McCoy, D., 2023. The political economy of infant and young child feeding: confronting corporate power, overcoming structural barriers, and accelerating progress. Lancet 401, 503–524. https://doi.org/10.1016/S0140-6736(22)01933-X.

Bulle, C., Margni, M., Patouillard, L., Boulay, A.-M., Bourgault, G., Bruille, V., Cao, V., Hauschild, M., Henderson, A., Humbert, S., Kashef-Haghighi, S., Kounina, A., Laurent, A., Levasseur, A., Liard, G., Rosenbaum, R.K., Roy, P.-O., Shaked, S., Fantke, P., Jolliet, O., 2019. IMPACT World+: a Globally Regionalized Life Cycle Impact Assessment Method.

Cadwell, K., Blair, A., Turner-Maffei, C., Gabel, M., Brimdyr, K., 2020. Powdered baby formula sold in North America: assessing the environmental impact. Breastfeed. Med. 15, 671–679. https://doi.org/10.1089/bfm.2020.0090.

Calvez, J., Blais, A., Deglaire, A., Gaudichon, C., Blachier, F., Davila, A.-M., 2024. Minimal processed infant formula vs. conventional shows comparable protein quality and increased postprandial plasma amino acid kinetics in rats. Br. J. Nutr. 131, 1115–1124. https://doi.org/10.1017/S0007114523002696.

CML-IA Characterisation Factors [WWW Document], 2016, Leiden Univ. https://www.universiteiteilen.nl/en/research/research-output/science/cml-ia-characterisation-factors.

Cornelus, M., Auberger, J., Rimbaud, A., Ceccaldi, M., 2024. AGRIBALYSE® version 3.2. https://doi.org/10.57745/XTENSJ.

Coulm, B., 2021. Allaiter en France aujourd'hui. Sages-Femmes 20, 10–12. https://doi.org/10.1016/j.sagf.2021.06.003.

Dadhich, J., Smith, J.P., Iellamo, A., Suleiman, A., 2021. Climate change and infant nutrition: estimates of greenhouse gas emissions from milk formula sold in selected Asia pacific countries. J. Hum. Lactation 37, 314–322. https://doi.org/10.1177/089033421994769.

Deglaire, A., Lee, J., Lanotte, L., Croguennec, T., Le Floch-Fouéré, C., Jeantet, R., Berkova, N., Pédrono, F., Le Loir, Y., Dupont, D., Gésan-Guiziou, G., Even, S., 2023. Towards more biomimetic and sustainable infant formula: challenges and future opportunities. Trends Food Sci. Technol. 137, 109–123. https://doi.org/10.1016/j.tifs.2023.05.010.

Depping, V., Grunow, M., Van Middelaar, C., Dumperl, J., 2017. Integrating environmental impact assessment into new product development and processing-technology selection: milk concentrates as substitutes for milk powders. J. Clean. Prod. 149, 1–10. https://doi.org/10.1016/j.jclepro.2017.02.070.

European Union, 2016. Commission Delegated Regulation (EU) 2016/127 of 25 September 2015 supplementing Regulation (EU) No 609/2013 of the European Parliament and of the Council as regards the specific compositional and information requirements for infant formula and follow-on formula and as regards requirements on information relating to infant and young child feeding. https://eur-lex.europa.eu/eli/reg_del/2016/127/oj/eng.

FAO, 2010. Greenhouse gas emissions from the dairy sector. A life cycle assessment. A report prepared by. Food and Agriculture Organization of the United Nations Animal Production and Health Division.

Fazio, Biganzioli, S., Laurentiis, F.D., Diaconu, S., Sala, 2018. Supporting information to the characterisation factors of recommended EF. Life Cycle Impact Assessment methods.
France, T.C., Kelly, A.L., Crowley, S.V., O'Mahony, J.A., 2021. Cold microfiltration as an enabler of sustainable dairy protein ingredient innovation. Foods 10, 2091. https://doi.org/10.3390/foods10092091.

France terre de Lait, 2022. France Terre de Lait : Rapport RS 2022. https://www.calameo.com/read/00223005183c51f468a21.

Gaillard, M., Saint-Preux, E., Deglaire, A., Goussé, E., Tanguy, G., Leconte, N., Guyomarc'h, F., Gésan-Guiziou, G., Floury, J., Submitted. Life cycle inventories and life cycle assessment datasets of a classic processing route for the manufacture of infant milk formula powder and of a low-heat alternative route involving the substitution of pasteurization by microfiltration. Data.

Gésan-Guiziou, G., Sobanitka, A.P., Omont, S., Froelich, D., Rabiller-Baudry, M., Thueux, F., Beudon, D., Tregret, L., Buson, C., Auffret, D., 2019. Life Cycle Assessment of a milk protein fractionation process: contribution of the production and the cleaning stages at unit process level. Sep. Purif. Technol. 224, 591-610. https://doi.org/10.1016/j.seppur.2019.05.008.

Guyomarc'h, F., Héquet, F., Le Féon, S., Leconte, N., Garnier-Lambrouin, F., Auberger, J., Malnoë, C., Pénicaud, C., Gésan-Guiziou, G., 2024a. Life cycle inventory and life cycle impact assessment datasets of an industrial-scale milk fractionation process generating 5 co-products: cream, casein, lactose and two whey-protein ingredients enriched in α-lactalbumin or β-lactoglobulin. Data Brief 55, 110676. https://doi.org/10.1016/j.dib.2024.110676.

Guyomarc'h, F., Héquet, F., Le Féon, S., Leconte, N., Garnier-Lambrouin, F., Auberger, J., Malnoë, C., Pénicaud, C., Gésan-Guiziou, G., 2024b. Life cycle assessment to quantify the environmental performance of multi-products food processing systems such as milk fractionation: importance of subdivision and allocation. J. Food Eng. 380, 112147. https://doi.org/10.1016/j.jfoodeng.2024.112147.

Huijbregts, M.A.J., Steinmann, Z.J.N., Elshout, P.M.F., Stam, G., Verones, F., Vieira, M., Zijp, M., Hollander, A., van Zelm, R., 2020. Correction to: ReCiPe2016: a harmonised life cycle impact assessment method at midpoint and endpoint level. Int. J. Life Cycle Assess. 25, 1635. https://doi.org/10.1007/s11367-020-01761-5, 1635.

ISO 14040, 2006. Management environnemental — Analyse du cycle de vie — Principes et cadre. https://www.iso.org/fr/standard/37456.html.

Jeantet, R., Brulé, G., Delaplace, G., 2011. Génie des procédés appliqué à l'industrie laitière, 2e éd., 2e ed. LAVOISIER, Paris.

Karlsson, J.O., Garnett, T., Rollins, N.C., Röös, E., 2019. The carbon footprint of breastmilk substitutes in comparison with breastfeeding. J. Clean. Prod. 222, 436-445. https://doi.org/10.1016/j.jclepro.2019.03.043.

Le Roux, L., Chacon, R., Dupont, D., Jeantet, R., Deglaire, A., Nau, F., 2020. In vitro static digestion reveals how plant proteins modulate model infant formula digestibility. Food Res. Int. 130, 108917. https://doi.org/10.1016/j.foodres.2019.108917.

Martin, C., Crépin, M., Feyen, V., Szleper, E., Gourrat, K., Leconte, N., Deglaire, A., Nicklaus, S., Lucchi, G., 2024. Effect of a minimal processing route for the production of infant formulas on their sensory properties. J. Dairy Sci. 107, 10527-10536. https://doi.org/10.3168/jds.2024-24937.

Milani, F.X., Nutter, D., Thoma, G., 2011. Invited review: environmental impacts of dairy processing and products: a review. J. Dairy Sci. 94, 4243-4254. https://doi.org/10.3168/jds.2010-3955.

Poore, J., Nemecek, T., 2018. Reducing food's environmental impacts through producers and consumers. Science 360, 987-992. https://doi.org/10.1126/science.aaq0216.

Salanave, B., Lebreton, E., Demiguel, V., Regnault, N., Epifane2021 Study Group, 2024. Alimentation des nourrissons pendant leur première année de vie. Résultats de l'étude Épifane 2021. Saint-Maurice : Santé publique France.

Schuck, P., Jeantet, R., Tanguy, G., Méjean, S., Gac, A., Lefebvre, T., Labussière, E., Martineau, C., 2015. Energy consumption in the processing of dairy and feed powders by evaporation and drying. Dry. Tech 33, 176-184. https://doi.org/10.1080/07373937.2014.942913.

UNICEF, 2022. Global UNICEF global databases: infant and young child feeding. Exclusive breastfeeding, New York, October 2022.

UNICEF, World Health Organization, 2007. Breastfeeding Manual for Health Workers Protecting, Promoting and Supporting Breastfeeding (Manual).

Verones, F., Hellweg, S., Antón, A., Azevedo, L.B., Chaudhary, A., Cosme, N., Cucurachi, S., de Baan, L., Dong, Y., Fantke, P., Golsteijn, L., Hauschild, M., Heijungs, R., Jolliet, O., Juraske, R., Larsen, H., Laurent, A., Mutel, C.L., Margni, M., Núnez, M., Owsianiak, M., Pfister, S., Ponsioen, T., Preiss, P., Rosenbaum, R.K., Roy, P.-O., Sala, S., Steinmann, Z., van Zelm, R., Van Dingenen, R., Vieira, M., Huijbregts, M.A.J., 2020. LC-IMPACT: a regionalized life cycle damage assessment method. J. Ind. Ecol. 24, 1201-1219. https://doi.org/10.1111/jiec.13018.

Yu, X., Leconte, N., Méjean, S., Garric, G., Even, S., Henry, G., Tessier, F.J., Howsam, M., Croguennec, T., Gésan-Guiziou, G., Dupont, D., Jeantet, R., Deglaire, A., 2021. Semi-industrial production of a minimally processed infant formula powder using membrane filtration. J. Dairy Sci. 104, 5265-5278. https://doi.org/10.3168/jds.2020-19529.

Zhang, Z., Zhang, J., Tian, W., Li, Y., Song, Y., Zhang, P., 2022. Multi-objective optimization of milk powder spray drying system considering environmental impact, economy and product quality. J. Clean. Prod. 369, 133353. https://doi.org/10.1016/j.jclepro.2022.133353.