
Sourdough breads are characterised by being made by slow fermentative processes, using a sourdough culture that is fermented with lactic acid bacteria and yeasts naturally present in the flour and in the air. These give the bread unique properties of flavour and aroma, making them tastier and more digestible.
These breads can show a better nutritional profile than conventional breads made with wheat flour and through rapid fermentation. In addition, different scientific studies show that these breads can exert healthier effects than the conventional ones, producing a lower increase in blood sugar after consumption. For this reason, a moderate intake of these breads accompanied by a healthy diet and lifestyle can help to protect us against the appearance of diabetes.
However, there is still little studies focused on the environmental impact of sourdough breads.
Identifying the environmental benefits of two sourdough breads production
The environmental impact associated with the production and consumption of food is very crucial for a sustainable world. In this sense, one of the highlights of the MED4Youth project is to identify the environmental benefits of using new ingredients to produce new bread.
Within MED4Youth, the project coordinator Eurecat has carried out an environmental assessment to perform a comparative quantitative environmental impact analysis of the production of the two types of sourdough breads developed under MED4Youth project: cider bread and multi-grain (MG) bread, in comparison with a conventional wheat bread with no sourdough content.
The cider bread was made with white wheat flour, sourdough and by-products of the cider industry, with low economic value but high nutritional benefits. The multi-grain bread was made with flours and seeds of different cereals and plants (wheat, millet, sesame, linen, rye, barley, buckwheat and oat) and leavened with sourdough.
The production of these two types of sourdough bread was carried out by NOVAPAN-PANISHOP, after analysing the results obtained with a survey, which was answered by 450 adolescents with the goal to elucidate the most appreciated bread attributes and the kind of bread teenagers mainly consume.
MED4Youth Life Cycle Assessment
Life Cycle Assessment (LCA) plays a key role in identifying the critical aspects and potential impacts of the current situation and in finding strategies that can help reduce the environmental impact. Hence the environmental performance of the bread production was calculated using the LCA methodology defined by the International Organization for Standardization.
For the purposes of this publication, the comparative analysis of the three above-mentioned breads focuses only on one indicator of Global Warming Potential (GWP) expressed in terms of mass of CO2 equivalent. The GWP is a concept created to allow comparisons of the global warming impacts of different gases. More concretely it describes the relative potency of a greenhouse gas, such as CO2, taking account of how long it remains active in the atmosphere.
As shown in Figure 1 the MED4Youth life cycle model covers the production chain from raw materials and packaging suppliers needed in the production of the bread, a step known as “the cradle” (Upstream), through the production until cold storage before shipment, known as “the gate” (Core) stage, hereinafter referred to as Cradle-to-Gate (Upstream-Core) analysis.
Figure 1. Diagram illustrating the processes that are included in the MED4Youth product study, divided into upstream and core process
Environmental analysis key results
- Cradle-to-Gate (Upstream-Core) analysis shows that the production of 1 kg of MED4Youth breads has approximately 40% less emission of CO2 to atmosphere than commercial bread, which is equivalent to about 200km driven by a passenger car.
- The GWP environmental indicator of the raw materials used in the production of 1 kg of bread is almost 70% lower in the case of raw materials used in the production of MED4Youth breads than for the commercial bread.
- Replacing wheat flour with seeds allowed to reduce CO2 emissions to 84% and cider pulp to 70% at the raw materials stage. Which on an annual basis corresponds to the cultivation of over 10 orange trees per year.
- Substituting wheat flour by another nutrient supplement such as fruit by-products in the case of cider bread, or seeds in the case of multi-grain bread, reduces CO2 emissions to the atmosphere by about 63% for cider bread and 70% for multi-grain bread at the raw materials stage.
- The cider bread uses almost five times less water for its production than in the case of commercial and multi-grain bread, which will save over 100 liters of water per year on one bread. This also translates into a reduction of CO2 emissions to the atmosphere by about 79% related to the water use in the production of 1kg of the bread.
- Energy used to produce 1 kg of bread is dominated by CO2 emission from cider bread (34%) and multi-grain bread (24%) compared to commercial bread.
About the author
Eurecat
Eurecat is the leading Technology Centre of Catalonia providing the industrial and business sector with differential technology and advanced expertise to boost their competitiveness in a fast-paced environment. The Biotechnology area of Eurecat is focused on the relation of nutrition with metabolic diseases such as obesity, metabolic syndrome and cardiovascular disease, behaviour and cognitive function and personalised nutrition using cutting edge methods and performing innovation in all omic sciences disciplines.