HortScience (Oct 2024)
Saga of Soggy Sauerkraut
Abstract
The creation of undesirable (soggy) sauerkraut resulted in the loss of $1,000,000 worth of organic sauerkraut in 2022, which prompted a multistep investigation of the cause and potential solution. The cause of this condition has been previously reported as unique fermentation conditions and the lack of key trace nutrients essential for cabbage (Brassica oleracea var. capitata) cell wall integrity. Because the condition was limited to organic sauerkraut in 2022, this investigation initially focused on differences in fermentation conditions between organic and conventional sauerkraut. No differences in fermentation conditions accounted for the condition; therefore, attention was focused on analyzing the mineral content of cabbage grown for sauerkraut production that pinpointed a deficiency in critical micronutrients such as iron, copper, manganese, boron, and zinc. This deficiency was traced to the use of poultry manure that was contaminated with glyphosate residue from conventionally fed turkeys and chickens that consumed genetically engineered (GE) feed and used as the fertilizer for organic cabbage production. The presence of glyphosate, a potent mineral chelator and antibiotic, was identified as a significant factor that impairs the absorption and physiological function of essential minerals in the shikimate metabolic pathway whereby cell walls and lignin are produced, thus compromising the structural quality of the sauerkraut. After this discovery, the study progressed to evaluate various remediation strategies aimed at eliminating glyphosate from the soil and restoring nutrient uptake. Corn grain and silage were selected as the test crops for this phase. Among the tested remediation solutions were raw sauerkraut juice containing Lactobacillus plantarum, which is reported to degrade glyphosate in the rumen of dairy cows and two patented proprietary microbial mixtures, PB027 and PB027SK, that degrade glyphosate by all three of the known metabolic pathways. These treatments were specifically formulated to degrade residual glyphosate in the soil. The results showed that these interventions could reduce soil glyphosate levels by 80% to 90% within 6 to 7 months to significantly enhance both the yield and quality of corn grain and silage. The increase in corn grain yield from glyphosate degradation on the Shiocton silt loam soil was 907.89 kg·ha−1 (13.5 bushels/acre). The increase in yield on the irrigated Kidder sandy loam soil was quantified at 726.31 kg·ha−1 (10.8 bushels/acre) for corn grain and 6.62 t·ha−1 (2.68 t/acre) for silage, with an additional improvement in silage feed quality beneficial for milk production. The findings underscore the importance of addressing both micronutrient sufficiency and glyphosate residue in soil to ensure the optimal growth of cabbage and the quality of sauerkraut produced. By successfully identifying manure as a subtle source of nutrient immobilization and implementing effective soil remediation techniques, this research highlights a clear path forward for improving crop yield and quality to ultimately enhance the structural integrity and consumer acceptance of sauerkraut. This study has broader applications for the nutritional content and crop yields of many organic crops that use conventional poultry and animal manures that may contain glyphosate in desiccated plant tissues or GE feeding operations.
Keywords