Abstract Implications of excess phosphorus (P) in waste streams obtained from soy‐based protein preparation processes on the environment and their potential utilization as P‐source are two significant understudied areas. Soybean‐based protein ingredients for food products retain comparatively enhanced functional properties and are cheaper than other plant‐based proteins. Soybean protein can be extracted and utilized as a food ingredient primarily by preparing soy protein concentrates (SPC) and soy protein isolates (SPI) from soybean meal/defatted soy flour (DSF). In a typical soybean processing facility, along with the soy products and soy‐protein preparations, the recovery of phosphorus as a coproduct will enhance the economic feasibility of the overall process as the recovered P can be used as fertilizer. In this study, the SPC and SPI were prepared from the DSF following widely used conventional protocols and P flow in these processes was tracked. In SPC production, ~59% of the total P was retained with SPC and ~34% was in the aqueous waste streams. For SPI process ~24% of total P was retained with SPI and ~59% went in the waste solid residue (~40%) and aqueous streams (~19%). About 80%–89% P removal from the waste aqueous streams was achieved by Ca‐phytate precipitation. This work demonstrated that in the process of SPC and SPI preparation the phosphorus from the waste aqueous streams can be precipitated out to avoid subsequent eutrophication and the waste solid residue with ~40% P can be reused as a P‐fertilizer as other applications of this residue are unspecified.
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Self‐healing efficiency of cinnamaldehyde‐crosslinked soy protein resins with elongated soy protein microcapsules
Abstract Self‐healing green thermoset soy protein isolate (SPI) based resins, crosslinked with cinnamaldehyde (CA), were developed. Self‐healing was achieved using elongated microcapsules (MCs) as against spherical MCs that have been used in most earlier studies. MCs containing SPI solution as healant within poly(d,l‐lactide‐co‐glycolide) shells were prepared using Water‐in‐oil‐in‐water (w/o/w) emulsion solvent evaporation (ESE) technique. Process parameters such as sodium tripolyphosphate (STP) and poly(vinyl alcohol) (PVA) concentrations and stirring speed were optimized to obtain elongated MCs. The average aspect ratio of MCs was over four. SPI resins crosslinked with 10% CA (10%CA‐SPI) increased Young's modulus and fracture stress by 54% and 87%, respectively, compared with their noncrosslinked counterpart. The resins containing 15% elongated MCs (15%MC‐10%CA‐SPI) showed self‐healing efficiencies of over 42% in fracture stress and about 35% in toughness recovery, after 24 h of healing. Improvement in self‐healing can be attributed to the high aspect ratio of the MCs that increases the probability of MCs being in the path of the microcracks and releasing the healant. Elongated MCs also contain higher amount of healant than spherical ones of same diameter. Self‐healing resins and composites can not only help prevent their premature failure but also improve their performance as well as service life and safety.
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- Award ID(s):
- 1719875
- PAR ID:
- 10549117
- Publisher / Repository:
- Wiley Online Library
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- Volume:
- 141
- Issue:
- 18
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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