The fermentability of agricultural raw materials by probiotic bacterial strains

¹ Wittmann Antal Multidisciplinary Doctoral School in Plant, Animal, and Food Sciences, Széchenyi István University, 2 Vár Square, 9200 Mosonmagyaróvár, Hungary
² Department of Food Science, Albert Casimir Faculty at Mosonmagyaróvár, Széchenyi István University, 15-17 Lucsony Street, 9200 Mosonmagyaróvár, Hungary

^* Corresponding author: asvanyi.balazs@sze.hu

Abstract

The objective of this study was to evaluate the fermentability of various agricultural raw materials using a novel Liquid State Fermentation (LSF) technique. The formulations were based on protein-rich plant ingredients, such as sunflower, wheat, and rapeseed, addressing the persistent issue of byproducts in the food industry by seeking alternative utilization methods. While the LSF method has been used in pork production, it remains a new technology in the poultry sector. Distiller’s Dried Grains with Solubles (DDGS) and Corn-Gluten Feed (CGF) were chosen based on previous experiments. These mixtures were enhanced by inoculation with various bacterial strains to produce fermented feeds with probiotic properties. The bacteria played a crucial role in the entire fermentation process. The starters included a commercial culture and fresh sweet whey of a semi-hard cheese. Additionally, selected bacterial strains were used based on previous research and literature data. Solaris model bioreactor system were utilized to produce the fermented feeds. This approach aims to promote a healthier gastrointestinal system in farm animals, protecting them against pathogenic bacteria. The fermentation process was designed to generate beneficial molecules such as enzymes, organic acids, and bacteriocins, further supporting the health benefits of the final product. This is significant because such feed can reduce the need for antibiotics in farm animal breeding, aligning with the EU’s stance on minimizing antibiotic usage. Throughout our research, we meticulously monitored the fermentation process, gathering data for a comprehensive comparison. Our analysis focused on changes in pH, the microbiological and hygienic properties of the feed, and the production of organic acids in the fermenting mixtures. The results consistently showed a decrease in pH values after 24 h of fermentation. DDGS with selected strains exhibited the highest LAB counts at 9.89 log₁₀ CFU/cm³, whereas the combination of CGF and whey produced the highest lactic acid concentration at 28.86 mg/ml. These promising results warrant further investigation through animal trials.