Bioprocessing of agro‐industrial residues into lactic acid and probiotic enriched livestock feed

Abstract

BACKGROUND: Growing challenges of resource depletion, food security and environmental protection are putting stress on the development of biorefinery processes for bioprocessing of residues from food and agro-industry into value-added products. In this study, the simultaneous production of lactic acid (LA) and livestock feed on a combined substrate based on molasses and potato stillage by Lactobacillus paracasei NRRL B-4564 immobilized onto sunflower seed hull (SSH), brewer's spent grain (BSG) and sugar beet pulp (SBP) was studied. RESULTS:The highest total LA concentration of 399 g L −1 with overall productivity of 1.27 g L −1 h −1 was achieved in repeated batch fermentation by SBP-immobilized biocatalyst, followed by BSG-and SSH-immobilized cells. Fermentation improved the content of proteins and ash, and decreased the content of fibers in all three support materials. In addition, the fermentation had favorable effect on in vitro dry matter digestibility and energy values of SSH and BSG. According to assessment of probiotic potential, L. paracasei demonstrated a favorable probiotic profile, exhibiting high resistance to simulated ruminant digestive tract and significant antioxidant and antimicrobial activity. CONCLUSIONS: The proposed strategy enables valorization of agro-industrial residues as value-added ruminant feed and simultaneous LA production. Following principles of circular economy, the developed process combines different raw materials and integrates them into a biorefinery process, improving the overall profitability and productivity. Probiotic potential of L. paracasei NRRL B-4564Phenotypic characteristics, such as survival in simulated conditions of GIT, antimicrobial and antioxidant activity, as well as J Sci Food Agric 2019; 99: 5293-5302

An Evolutionary Approach on the Framework of Circular Economy Applied to Agriculture

“…The rest of the disciplines are not represented graphically since their representation percentage is under 5%. Even so, variety is mentioned in the rest of the disciplines framed since there are publications in the field of Nursing, Veterinary, or Neuroscience [47,48]. Finally, to obtain an overview of the number of categories in which the investigations are classified, it must be said that a total of 2320 documents are registered for the 26 categories.…”

Fermentative Lactic Acid Production From Lignocellulosic Feedstocks: From Source to Purified Product

“…The LA productivity was 1.48 g/l.h. In a later paper (Mladenovic et al, 2019) extended their research on the possibility of simultaneous production of LA and probiotic enriched livestock feed on a combined substrate based on molasses and potato stillage. The highest total LA concentration of 399 g/L and overall productivity of 1.27 g/l.h was achieved in five repeated fermentation batches.…”

Application, characterisation and economic assessment of brewers’ spent grain and liquor

“…The economic application of brewers' spent grain in a refinery has been demonstrated (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)66). In the literature, a biomass input of 1,500-6,000 tonnes/day is reported as economically feasible for a biorefinery.…”

“…There are numerous concepts for utilisation in a biorefinery with targeted hydrolysis of the main components of the spent grain, such as lignin and hemicellulose, using enzymes or chemicals. Various products including ethanol, lactic acid, xylitol can be generated in the process (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). According to Spekreijse et al (24), the total bio-based manufacturing of products in the European Union was 4.7 million tonnes in 2019 which represents a market share of 3%.…”