Environmental Benefits of Novel Nonhuman Food Inputs to Salmon Feeds

Abstract

Global population growth and changing diets increase the importance, and challenges, of reducing the environmental impacts of food production. Farmed seafood is a relatively efficient way to produce protein and has already overtaken wild fisheries. The use of protein-rich food crops, such as soy, instead of fishmeal in aquaculture feed diverts these important protein sources away from direct human consumption and creates new environmental challenges. Single cell proteins (SCPs), including bacteria and yeast, have recently emerged as replacements for plantbased proteins in salmon feeds. Attributional life cycle assessment (ALCA) is used to compare salmon feeds based on protein from soy, methanotrophic bacteria, and yeast ingredients. All ingredients are modeled at the industrial production scale and compared based on seven resource use and emissions indicators. Yeast protein concentrate showed drastically lower impacts in all categories compared to soy protein concentrate. Bacteria meal also had lower impacts than soy protein concentrate for five of the seven indicators. When these target meals were incorporated into complete feeds the relative trends remain fairly constant, but benefits of the novel ingredients are dampened by high impacts from the non-target ingredients, Particularly, primary production requirements (PPR) are about equal and constant across all feeds for both analyses since PPR was driven by fishmeal and oil. The bacteria-based feed has the highest climate change impacts due to the use of methane to feed the bacteria who then release carbon dioxide. Overall, the results of this study suggest that incorporating SCP ingredients into salmon feeds can help reduce the environmental impacts of salmon production. Continued improvements in SCP production would further increase the sustainability of salmon farming.

Using Techno-Economic Modelling to Determine the Minimum Cost Possible for a Microbial Palm Oil Substitute

“…Oleaginous yeasts were originally grown for their protein content [5] and use of oleaginous biomass produced for aquafeed has also been reported [68]. There has been a growing interest in producing microbial feed ingredients as animal feed additives, using bacteria and yeasts [69]. Using intact cells as a feed ingredient, takes away a large part of the recovery process and most importantly the need to use solvent to extract the lipids.…”

Sustainable Animal Feed Protein through the Cultivation of YARROWIA Lipolytica on Agro-Industrial Wastes and by-Products

“…According to two recent studies, that used LCA methodology to compare the environmental impacts of soybean meal against various alternative protein meals for salmon [39] and broiler feed [7], yeast-based SCP is considered to be more environment-friendly compared to imported vegetable protein (e.g., soybean meal). Couture et al [39] assessed the environmental impact of salmon feeds formulated and used in a salmon farm located in Norway. The main protein sources considered were soybean meal, produced and imported from America, against bacteria protein meal (BPM), produced and imported from the USA, and yeast protein meal (YPM), produced locally in Norway.…”

“…Given that each LCA model is based on a number of assumptions, Couture et al [39] performed sensitivity analyses to assess the effect of the production location and the allocation method that was employed (e.g., economically-based vs. mass-based). While the results had small variations, the relative results were the same.…”

“…Technol. 2019,53,4,[1967][1968][1969][1970][1971][1972][1973][1974][1975] [39]. Copyright 2019 American Chemical Society.…”

Edible Microorganisms—An Overlooked Technology Option to Counteract Agricultural Expansion

“…However, such an approach would need to be carefully evaluated to determine whether any net negative emissions gained from large-scale land sparing risk being offset by the embedded carbon footprint of the necessary industrial infrastructure in addition to any emissions associated with its energy consumption. The current literature on the environmental footprint of microbial sources of food and feed have focused on processes that use feedstocks derived from either agriculture or natural gas (see for instance Smetana et al, 2015;Pikaar et al, 2018;Couture et al, 2019). Additional studies are necessary to evaluate emissions and other environmental costs of microbial feed and food production processes that employ direct CO 2 capture and conversion as the process described above.…”