Maize Processing Waste Water Upcycling in Mexico: Recovery of Arabinoxylans for Probiotic Encapsulation

Maize is a major source of food in Mexico. In order to improve its nutritional value, maize kernel is exposed to an alkali treatment that generates large volumes of waste water containing gelling arabinoxylan. The purpose of the present study was to evaluate the capability of maize waste water arabinoxylans (MWAX) to encapsulate probiotics. The rheological, structural, and microstructural characteristics of this bio-based material were also investigated. MWAX gels at 10% (w/v) were able to encapsulate Bifidobacterium as probiotic model. The MWAX gel containing 1 × 107 CFU/mL of probiotics presented a storage (G′) and loss (G″) moduli of 50 and 11 Pa, respectively. The average mesh size of the MWAX gel was around 11 times smaller than the Bifidobacterium cell magnitude. MWAX gels with or without probiotics were studied using scanning electron microscopy. The interior of the Bifidobacterium loaded gels was composed of a pore-like network of MWAX through which probiotics were distributed. The probiotic encapsulating MWAX gels appeared to be less porous than the empty gels. MWAX capability to encapsulate Bifidobacterium may be important in designing probiotic encapsulating biodegradable gels and could represent an opportunity in sustainable food waste management and utilization through upcycling to value-added products.