As part of the work in the LIVESTOCK project a new paper has now been published. It is a life cycle study of the environmental impacts of pig production when the soybean meal in the feed is replaced by yeast protein produced from wood sugar. 

The raw material for the yeast protein is hydrolysed wood sugar that can be produced from wood through a biorefining process. In this study, two processes were analysed: wood sugar (Excello) from Borregaard and wood molasses that can be hydrolysed to wood sugar from Glommen Technology. These processes are not yet in commercial operation in Norway, so the data in the study is based on test production and technical calculations.

The wood sugar is further used as the main component for fermentation of yeast, which in turn can be used as a protein source in feed for pigs. The results show that when this is compared with standard feed that contain soybean meal, the feed with yeast from wood sugar will have lower environmental impacts, especially reduced loss of biodiversity. It will also reduce the feed-food competition for arable land. Although the area requirement per kg of carcass weight is greater if wood sugar is used in the feed compared to soybean meal, the forest area cannot be used for food production. The use of wood sugar can also increase resource utilization because the refinery processes can use residual wood that does not meet the fibre length requirements for the cellulose and paper industry, e.g. sawdust.

Read the article here: https://www.sciencedirect.com/science/article/pii/S1871141322001056?via%3Dihub

Photo: Håkon Sperre, NMBU