TY - JOUR
T1 - Whey Protein Isolate-Based Aerogels with Improved Hydration Properties for Food Packaging Applications
AU - Effraimopoulou, Eleni
AU - Kalmár, József
AU - Paul, Geo
AU - Marchese, Leonardo
AU - Ioannou, Dimosthenis
AU - Paraskevopoulou, Patrina
AU - Gurikov, Pavel
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/1/12
Y1 - 2024/1/12
N2 - In the present work, tannin-modified whey protein isolate (WPI/tannin) aerogels were synthesized, and their hydration properties were evaluated. The materials were prepared by introducing two different tannins (one hydrolyzable and one condensed) in the protein matrix via thermal-induced gelation of neutral or alkaline aqueous solutions (pH 7, 9, or 11) at 80 °C. WPI and WPI/tannin aerogels are nanostructured porous materials with high BET surface areas (216-353 m2 g-1). Subsequently, WPI and WPI/tannin aerogels were hydrophobized via silanization (with bis(trimethylsilyl)amine) in the gas phase (HWPI and HWPI/tannin aerogels). As a result of silanization, BET surface areas were reduced to 87-242 m2 g-1. The hydration properties of all aerogels were studied by measuring the water uptake and water contact angles. Pristine WPI aerogels absorbed high amounts of water (up to 4794% w/w in 24 h), swelled, and eventually disintegrated. WPI/tannin aerogels prepared with the condensed tannin absorbed more water (219-559% w/w) than those prepared with the hydrolyzable tannin (81-88% w/w). In any case, the water uptake was significantly lower compared with that of pristine WPI aerogels. After silanization, all aerogels absorbed much smaller amounts of water (39-84% w/w). The reduced water uptake was in agreement with the water contact angles, which were in the ranges 35-55° for WPI aerogels, 40-60° for WPI/tannin aerogels, 80-86° for HWPI aerogels, and 100-116° for HWPI/tannin aerogels. These results clearly indicate that both the introduction of tannin in the protein matrix and the silanization of the solid network are necessary to obtain water-stable WPI-based aerogels. There is an immense need for replacing the existing plastic-based food packaging with biobased and biodegradable materials. In this context, our results address the major disadvantage of most biobased materials (i.e., poor stability in aqueous environments) and render these new aerogels good candidates for food packaging applications.
AB - In the present work, tannin-modified whey protein isolate (WPI/tannin) aerogels were synthesized, and their hydration properties were evaluated. The materials were prepared by introducing two different tannins (one hydrolyzable and one condensed) in the protein matrix via thermal-induced gelation of neutral or alkaline aqueous solutions (pH 7, 9, or 11) at 80 °C. WPI and WPI/tannin aerogels are nanostructured porous materials with high BET surface areas (216-353 m2 g-1). Subsequently, WPI and WPI/tannin aerogels were hydrophobized via silanization (with bis(trimethylsilyl)amine) in the gas phase (HWPI and HWPI/tannin aerogels). As a result of silanization, BET surface areas were reduced to 87-242 m2 g-1. The hydration properties of all aerogels were studied by measuring the water uptake and water contact angles. Pristine WPI aerogels absorbed high amounts of water (up to 4794% w/w in 24 h), swelled, and eventually disintegrated. WPI/tannin aerogels prepared with the condensed tannin absorbed more water (219-559% w/w) than those prepared with the hydrolyzable tannin (81-88% w/w). In any case, the water uptake was significantly lower compared with that of pristine WPI aerogels. After silanization, all aerogels absorbed much smaller amounts of water (39-84% w/w). The reduced water uptake was in agreement with the water contact angles, which were in the ranges 35-55° for WPI aerogels, 40-60° for WPI/tannin aerogels, 80-86° for HWPI aerogels, and 100-116° for HWPI/tannin aerogels. These results clearly indicate that both the introduction of tannin in the protein matrix and the silanization of the solid network are necessary to obtain water-stable WPI-based aerogels. There is an immense need for replacing the existing plastic-based food packaging with biobased and biodegradable materials. In this context, our results address the major disadvantage of most biobased materials (i.e., poor stability in aqueous environments) and render these new aerogels good candidates for food packaging applications.
KW - Fintan C
KW - Fintan QS-Sol
KW - aerogels
KW - biobased aerogels
KW - bis(trimethylsilyl)amine
KW - food packaging
KW - hydration properties
KW - hydrophobization
KW - tannin
KW - whey protein isolate aerogels
UR - http://www.scopus.com/inward/record.url?scp=85182013195&partnerID=8YFLogxK
U2 - 10.1021/acsanm.3c04784
DO - 10.1021/acsanm.3c04784
M3 - Article
SN - 2574-0970
VL - 7
SP - 618
EP - 627
JO - ACS Applied Nano Materials
JF - ACS Applied Nano Materials
IS - 1
ER -