CARIBOU: CirculARIty of the Bakery prOdUction

CARIBOU is an exploratory project that brings together skills in social sciences, humanities, environmental assessment and technology to help develop bread recovery sectors.

Context and challenges

Food losses and waste have been estimated at 20-30% of production [1,2] in France. These losses are distributed all along the food chain, from production to consumption, with 35% cumulating at the processing and distribution stages for all types of food products combined [3]. The 2016 Garot Law introduced a two-fold obligation: to gradually reduce the quantity of bread waste and to recover it according to a hierarchy that gives priority to food for humans (preventing waste, donating to charities, reusing for the manufacture of food products, on-site or not), followed by feed for animals, and lastly composting and energy production. The “food first” priority is stressed, and often justified as also a way to minimise the environmental footprint of products [1,2].
The bread-making sector uses 36% of the non-exported wheat flour produced in France [4]. Artisanal production and industrial production represent 57% and 33% respectively. The volume of bread waste has been the subject of few studies along the supply chain; there is an estimate based on national data [4] and a study based on surveys in artisanal bakeries and supermarkets at national level (17 surveys) carried out by ADEME [3]. According to [4], bread waste represents about 500,000 and 270,000 t in industrial processing and distribution respectively (120,000 and 150,000 t from artisanal bakeries and supermarkets respectively). On the one hand, distribution flows may be explained by the limited freshness of bread, which rarely exceeds one day for fresh-baked products and three weeks for so-called long-life breads. On the other hand, bread waste flows at industrial level is highest due to the quantity produced and despite processes that are already highly optimised (around 0.5% of losses for a large production site near the city of Rennes [5]). The sustainable management of bread waste is more apt to a local context, and to our knowledge there is no documentation on the local distribution of these flows.

Goals

CARIBOU brings together skills in social sciences, humanities, environmental assessment and technology to help develop these recovery sectors. The overall goal is to carry out research that fosters a circular breadmaking sector from a socio-economic, organisational and technological standpoint, and that also sheds light on - and even calls into question - the regulatory hierarchy of the uses of bread waste. It aims firstly to better characterise the flows of this bread waste and especially their territorial specificity. This stage is crucial in order to define the most relevant research topics with a view to future research and action. CARIBOU seeks to reflect on the most appropriate economic model to allow for several uses to co-exist, especially those with a strong social function (donations to charities, local synergies that forge ties in territories). Lastly, CARIBOU questions the hierarchy of uses as laid out in current regulations (Garot law 2016), and calls for a contextualisation of uses before defining such a hierarchy. As such, the project proposes to explore new recoveries considered intermediate priorities in the regulatory hierarchy. The goal is to test the first feasibility conditions to perhaps follow up with another project in future.

Three research goals have been set by the CARIBOU project:

establish an estimate of available bread waste deposits and identify the determining factors in order to better shape its future (see point c). BVP production – and therefore the generation of bread waste - is concentrated in urban and peri-urban territories (artisanal bakeries and convenience stores; supermarkets, medium-sized workshops supplying collective catering in cities: schools, hospitals, nursing homes, prisons, etc.). Even large BVP production sites, primarily dedicated to export, are located in the outer ring of big cities, less than 10 km away from centres (eg Château Blanc near Lille, Jacquet near Clermont-Ferrand, Bridor or van de Moertel near Rennes). Bread waste flows, which still need to be accurately mapped, seem both centred in cities (donations, re-use on production sites) and turned toward the hinterland (flour for livestock). Therefore, a better identification of these deposits and a more detailed diagnosis of where they end up in this potential city-hinterland dynamic are essential to shaping the urban and peri-urban metabolism of bread waste
explore the feasibility of innovative recovery routes. The focus is on the feasibility of two innovative recovery routes: the first contributes to the protein autonomy of breeding territories. The bread waste flows targeted are from supermarkets as they make their way from city outskirts to the hinterland (livestock farms). It involves evaluating the feasibility of optimising the nutritional value of bread waste inspired by the “natural” processing of organic matter by way of fungi [6]. This task echoes axis 1.2 of the Metaprogramme BETTER, even if it does not concern actual residual products but rather a material specific to food. The second aims to study the recovery routes of bread waste flows and associated waste (unfit for consumption). It involves assessing feasibility and identifying conditions for obtaining molecules of interest (platforms or bio-active) on the basis of biological processes (notably fermentation). The scale of the solution can be local or centralised depending on the results obtained in (a). This task contributes to axis 2.2 of the Metaprogramme BETTER.
prepare the construction of future organisational plans of potential sectors for recovering bread waste while respecting, and even facilitating, the social function (donations, local synergies) and responding to the needs of territories where bread waste is produced.

Progress and results

An analysis of the literature over the period 2016-2022 showed that, for this bioresource, the articles cover all conceivable valuations listed in the regulatory hierarchy. A formalisation of the scientific literature review on URB valuation over the period 2016-2023 was newly submitted to the Journal of Industrial Ecology. This work quantitatively confirmed that the research effort, while focused on all valorization routes for this substrate, was unbalanced in relation to the hierarchy recommended by the regulations (quantified on the basis of the proportion of articles per valorization type over the period). CARIBOU provided an opportunity to reflect on the criteria that should guide the decision-maker's choice of recovery route. Compared with the previous period, the research effort was clearly in line with the original intention of the product studied (prevention and recycling for human consumption). This last result was a determining factor in the direction taken for the ANR AAPG 2023 (μCosmos) submission. Finally, CARIBOU pointed out that the prevention stage could conceal part of the impact (cases where the URB producer does not dispose of it and mobilises actions lower down the
hierarchy on site) and that the yield of the recovery operation was too often overlooked in the research published to date (biorefineries in particular). This reflection has guided the positioning of Task 2 of the Projetc, with, for example, the exploration of RIP fermentation without sterilisation or inoculation.
CARIBOU has also explored fungal or mixed (yeast/bacteria) recovery methods, with a focus on process simplicity (without sterilisation and/or extraction). The literature review highlighted the fact that most of the routes described in the literature are implemented using pure strains, which more often than not require the medium to be sterilised and an often complex final purification stage to extract the molecule of interest. All of these constraints have a negative impact on the economics of these processes, and very few cases of the production of molecules of interest on an industrial scale have been described. The energy required to sterilise URBs, the complexity of the technologies used and the management of residues linked to the low mass yield of production limit the environmental benefits of using URBs to produce molecules of interest. The first trials carried out at OPAALE-PANDOR research units showed that whatever the type of bread (wholemeal bread, white flour baguette or long-life sandwich bread) and the storage conditions, butyric fermentation dominated in 7 out of 9 configurations. In the other two cases, fermentation tended towards malolactic fermentation. The secondary molecules produced were acetic and succinic acids. Butyric acid has recognised anti-inflammatory
properties, and a great deal of work is underway to assess the health benefits of adding this acid. Three strains from the collection of the Centre International des Ressources Microbiennes -Banque de Ressources Fongiques de Marseille were targeted, among species known to be edible (Agaricus bisporus, Lentinula edodes and Pleurotus ostreatus). Based on macroscopic observations of the cultures (colonisation rate and density), the Pleurotus ostreatus strain, BRFM 1326 was selected. The amino acid profile and compositional analyses of total dietary fibre in the bread sample colonised by the fungus compared with the control bread showed a nutritional benefit provided by the fungal culture. In particular, the quantity of insoluble dietary fibre and resistant starch more than doubled.
The flows of URBs, by way of local recovery, and their determinants were studied by means of surveys of bakery actors (artisanal bakeries (AB), industrial or semi-industrial bakeries) or distribution (supermarkets and hypermarkets) and charities in Rennes Métropole (RM) and la Plaine Commune (PC) in the Paris region.
1. Access to medium and large-scale retailers proved difficult. A total of around twenty surveys were carried out in the two areas, most of them with floor managers. It was found that supermarkets first seek to prevent losses (batch promotions because of financial management at department level), then request bio-waste collection (AGEC law for large producers). The results for retailers are similar in both areas.
2. Unsurprisingly, mini-markets, which are often not covered by the regulations (obligation to sort bio-waste, food donation agreement), almost always dispose of their waste in household waste (tomorrow in a bio-waste collection scheme.
3. In the light of initial surveys of charities, and particularly in la Plaine Commune, bread does not seem to be a key food product for food aid, which explains why it is a minor source of value in supermarkets. Bread made from white flour is not taken up by food aid (‘duck bread’ because it is just good to give to ducks), which echoes the selection of special breads by those involved in food recycling, whether in microbreweries (cereal bread) or biscuit factories (organic sector). This implies that (i) these two uses should not be dissociated, as they may be in ‘competition’ for the same material, (ii) white bread could be used in a low-value sector (animal feed or biorefinery?) without competing for the resource with human food, and (iii) white bread could be used in a low-value sector (animal feed or biorefinery?) without competing for the resource with human food.
4. The semi-industrial or industrial Bakery, Viennoiserie and Patisserie (BVP) production (4 surveys in Rennes Métropole) mainly recycles for food aid and animal feed; bio-waste collection is used as an alternative. These players are all interested in food recycling (whether in a closed loop or not), but have not taken the plunge (at the test stage at most). The difference with supermarkets for food aid can be explained by the nature of the gap (production gap available from the morning of the production day versus end-of-day surplus available the following day).
5. A territorial metabolism has been sketched out in Rennes Métropole for small-scale bakeries. Subject to confirmation, a significant flow linked to prevention (~20% in total) was revealed by this analysis and the portfolio of recovery seems different in rural areas (few visits by associations for food aid and more ‘bartering’). It is planned to complete this work as part of the ANR ‘μCOSMOS’ project.

Project sheets

Contacts - Coordination

Tiphanie LUCAS, UR OPAALE , TRANSFORM division, tiphaine.lucas@inrae.fr

Project participants

The project is made up of people from different INRAE fields, research units and divisions who wish to open up dialogues between their research to rise to the societal and scientific challenges of tomorrow’s cities.

INRAE structures

TRANSFORM division
UR OPAALE	Environmental assessment, Life cycle analysis, Organic waste management facilities in territories Spatial modelling Analysis of bread waste flows, interdisciplinary analysis of territorial metabolism Process engineering, applied to recovering waste (livestock effluents, sludge from former treatment plants) by organic means Microbial enzymology, applied to recovering agro-industrial waste Analysis of fibres
ACT division
UMR SADAPT	Territorial ecology, estimates of flows from surveys and database analysis, analyse interdisciplinary analysis of territorial metabolism
MICA division
UMR BBF	Help in selecting strains and fungal growth

Name of the cookie	Purpose	Shelf life
CAS and PHP session cookies	Login credentials, session security	Session
Tarteaucitron	Saving your cookie consent choices	12 months

Name of the cookie	Purpose	Shelf life
atid	Trace the visitor's route in order to establish visit statistics.	13 months
atuserid	Store the anonymous ID of the visitor who starts the first time he visits the site	13 months
atidvisitor	Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.	13 months