We just added this info to Vitamin B12 in Plant Foods:
While tempeh is usually made by fermenting soybeans, it can also be made using a different species of legume, lupine beans. The fungus used to create lupine tempeh is Rhizopus oligosporus, which doesn’t produce B12. However, Signorini et al. (2018) added a B12-producing bacteria, Propionibacterium freudenreichii, to the tempeh fermentation process resulting in 1.2 µg of B12 per 100 g dry weight of the lupine tempeh. The study didn’t address the costs of producing B12 in this way compared to simply producing supplements, but this fermentation process holds promise as a way to provide a source of B12 in plant foods.
4 thoughts on “Lupine Tempeh as a Potential Source of B12”
Rhizopus Oligosporus is a mold, not a bacterium
Fixed. Thank you.
Did they try using the B12 producing bacteria with soybeans? What do lupine beans have that soybeans lack?
Mitchell,
From the paper:
> Lupin contains lower amounts of both fats and antinutritional compounds than soybean (Duranti et al. 2008) and has non-gen- etically modified status. The presence of the bitter-tasting neurotoxic alkaloids is a main issue that limits the use of lupin-based foods. The lowest alkaloids content is reported in L. albus varieties (Reinhard et al. 2006; Boschin et al. 2008), whereas the highest in L. mutabilis (Hatzold et al. 1983). However, low-alkaloid lupin varieties are available (Wink et al. 1995, 2011; Kouris-Blazos & Belski 2016). The maximum permitted level of quinolizidine alkaloid content in lupin flours and foods was set at 0.02%. The daily intake of alkaloid for humans was suggested as 0.035 mg/kg body weight/day (ANZFA 2001). Rhizopus spp. fermentation has been reported as an effective to reduce the presence of alkaloids (Jimenez- Martınez et al. 2007; Ortega-David & Rodrıguez- Stouvenel 2013) and of other undesirable compounds (Fudiyansyah et al. 1995) in lupin.
> Tempeh has been described as one of the first plant-derived food containing relevant amounts of vitamin B12 (2–40 ng/g dry weight) (Liem et al. 1977; Bisping et al. 1993; Keuth & Bisping 1994). However, it has been shown that the vitamin was produced not by the R. oligosporus starter culture used, since this species is incapable to synthesise it (Keuth & Bisping 1993), but by contaminating bacteria, such as Klebsiella pneumoniae, Citrobacter freundii (Keuth & Bisping 1994), Bacillus megaterium and Streptomyces olivaceus (Krusong et al. 1991).
> Attempts to increase the vitamin B12 content of soyabean tempeh have reported by using R. oligosporus cofermentation with C. freundii (Denter & Bisping 1994; Wiesel et al. 1997) or Propionibacterium shermanii (Krusong et al. 1991). The vitamin B12 levels in these cofermentations reached about 59ng/g dry weight and 1.85ng/g dry weight, respectively. On the contrary, cofermentation with Lactobacillus plantarum was not effective, since the content of vitamin B12 was less than 1ng/g dry weight (Mo et al. 2013).
> In this work, we investigated the possibility of producing a tempeh analogue containing high amounts of vitamin B12 using seeds of different lupin species, namely L. albus, L. angustifolius and L. mutabilis, while also monitoring any decrease in alkaloid levels.