The extended use of fractionation processes

Abstract

Winnowing, flour milling and sugar extraction are traditional examples of the mechanical fractionation of agricultural products. Fodder fractionation is more novel. It enables a protein-rich fraction to be separated, for use by people and other non-ruminants, from a more fibrous fraction that can be used as ruminant feed. Because the fibre is partly dewatered in the process, less energy is needed to dry it than to dry the original forage for conservation as winter feed. The ‘whey’ remaining after separating protein from the expressed juice could simply be returned to the land as a source of nitrogen, phosphorus and potassium - perhaps after being used as a substrate for microorganisms. Besides being used on crops grown specially for the purpose, fodder fractionation can be applied to various market garden and farm by-products - even to some, such as potato haulm, that are usually considered inedible. The process of extraction destroys detrimental physical structures and the ‘whey’ removes toxic components.

White clover fractions as protein source for monogastrics: dry matter digestibility and protein digestibility‐corrected amino acid scores

“…Processing of white clover plants can overcome the limitations of the direct utilisation of the fresh plant for monogastric feeding; namely, the high fibre content, high water content and the presence of other nutritionally unfavourable components. 13 Furthermore, the production of a shelf life stable product could enhance the usability in compound feeds (and food matrices). However, knowledge of the effect of processing white clover on the nutritional quality is limited.…”

“…Processing of green biomass in a twin screw-press, followed by extracting the soluble protein concentrates and leaving the majority of the plant fibre in the resulting pulp, 12,13 will theoretically generate a pulp fraction with a low digestibility for monogastrics. Interestingly, the present study demonstrated a high digestibility of protein in all fractions, irrespective of the physical fractionation increasing the possibility of utilising all fractions for monogastric feed purposes.…”

“…Proteins are mainly concentrated in plant leaves and earlier research has primarily been focused on extracting proteins from the green leaves. Davys and Pirie and Pirie, studied and optimised the process of separating green leaves into a liquid fraction (juice) containing soluble proteins and a fibrous solid fraction (pulp). The juice can be processed into a protein‐rich concentrate, thus removing a large proportion of unwanted components .…”

Biorefinery of Green Biomass─How to Extract and Evaluate High Quality Leaf Protein for Food?

“…To make the leaf proteins available for monogastrics, the proteins need to be extracted from the plant matrix. The historical advances in leaf protein extraction and production have been reviewed several times by Pirie. − A number of different leafy plants can be used for extraction of leaf protein (including tropical/subtropical species), but the research and development on leaf protein extraction has mainly been focusing on alfalfa ( Medicago sativa ), which is one of the most important forage crops across the world. However, other legumes such as red clover ( Trifolium pratense ), white clover ( Trifolium repens ), and grasses (e.g., Lolium , Festuca and Festulolium spp.)…”