Spent brewer’s yeast encapsulated by spray drying: a promising bioproduct for dairy cow feeding supplementation

This study aimed to encapsulate spent brewer’s yeast (SBY) (Saccharomyces spp.) by spray drying employing cheese whey (CW) and autolyzed spent brewer’s yeast (AY) as encapsulating agents to maintain the cell viability of the product during processing, storage, and in the digestive tract. The ratio between core (SBY) and encapsulating agents (CW and AY) applied was 1:15, with 50% CW and 50% AY (50:50), and 70% CW and 30% AY (70:30). The survival rate of the samples overcame 96%. After 90 days of storage, yeast survival decreased to 75% and 69% (50:50 and 70:30, respectively). Sample 70:30 showed lower hygroscopicity, moisture, and water activity after 90 days of storage, compared to sample 50:50. In the gastrointestinal tract, sample 50:50 showed higher resistance than sample 70:30 and free cells as control, showing 56% of survival on day 0 and 40% of survival after 90 days of storage. Encapsulated SBY capacity to resist spray drying, storage conditions (3 months), and digestive tract makes Saccharomyces spp. encapsulated with CW and AY, a promising candidate for the development of studies regarding encapsulated probiotics for dairy feed supplementation.