Objectives Brewers’ spent grain (BSG), the most abundant by-product of the brewing industry, consist of malted barley residue leftover from beer production and are rich in fiber and protein. This study examined whether regular consumption of upcycled BSG flour can modulate blood biomarkers of cardiovascular disease (CVD), glucose homeostasis, inflammation, and body composition in healthy adults. Methods Muffins containing 7.5 g BSG (20% wt: wt flour), 11.2 g BSG (30% wt: wt flour), and 0 g BSG (control) were developed and tested for consumer acceptability on overall liking, appearance, texture, moistness, sponginess, and taste. BSG muffins that maintained mean ratings of 5 or higher on a 9-point hedonic scale were considered acceptable and included in a feeding trial. A single-blind, randomized, placebo-controlled human feeding trial compared consumption of muffins with 12 g BSG (30%) or 0 g BSG daily for 8 weeks. BSG and control muffins were similar in total calories (BSG: 306 kcal, control: 307 kcal) and available carbohydrates (BSG: 51.2 g, control: 52.0 g). Fasting blood was collected for glucose, insulin, and lipid measurements and body composition was assessed using air displacement plethysmography at baseline and 8-weeks. During the 8 weeks of intervention, participants recorded 3-day food logs, 2-day stool logs to monitor changes in bowel movements and symptoms, and daily muffin consumption. Results Consumer testing (n = 107) found significant differences among appearance (F = 7.728, P = .001) and taste (4.947, P = .008) ratings across all muffins. Control (6.74 ± 1.84) and 20% (6.64 ± 1.90) muffins received higher appearance ratings and higher taste ratings for 20% muffins (7.15 ± 1.72). Additionally, 30% muffins had acceptability. In the feeding trial, 18 participants (26.8 ± 4.0 y) with a BMI of 23.4 ± 3.2 kg/m2completed the study. Systolic blood pressure (BP) (P = .044) and insulin (P = .011) were lower in the BSG group than the control group after consuming study muffins for 8-weeks. There were no significant treatment effects for glucose concentrations or body composition outcomes between test groups or over time. Conclusions Consuming BSG reduces systolic BP and insulin in healthy adults compared to control muffins. A higher BSG dosage or consuming BSG for a longer duration may be necessary to observe additional clinical endpoints. Funding Sources Moore-Khourie Fund.

Objectives The brewing industry generates larges amounts of leftover malted barley and grain adjuncts from beer production called brewers’ spent grain (BSG). Due to the high protein and fiber content, upcycling BSG into functional foods has gained recent interest. Observational studies demonstrate fiber-rich whole grains such as barley are associated with cardiovascular disease (CVD) risk reduction. This study evaluated the effect of BSG on blood biomarkers of CVD risk, glucose metabolism, insulin sensitivity, inflammation, body composition, and blood pressure. Methods A single-blind, randomized, controlled feeding study was conducted in 37 healthy adults (26 ± 4 y; BMI 23 ± 3 kg/m2) comparing consumption of muffins with 10.4 g BSG (n = 19) or 0 g BSG (control; n = 18) daily for 8 weeks. At baseline and week 8 fasting blood was collected for lipids, glucose, insulin, and C-reactive protein, blood pressure was measured using the oscillometric technique, and body composition was assessed using air displacement plethysmography. Participants also recorded 3-day dietary intake, 2-day gastrointestinal symptoms and bowel habits, and daily muffin consumption. Two-way repeated-measures mixed analysis of variance (ANOVA) and Fisher's Least Significant Difference (LSD) tests examined between- and within-group differences. Results Dietary fiber intake increased in the BSG group (5 g/day; 26%; P = 0.003), but there were no significant effects on blood lipids, glucose metabolism, insulin sensitivity, inflammation, body composition, or blood pressure. Greater reductions of total cholesterol (-3.8 mg/dL), triglycerides (-3.4 mg/dL), and systolic blood pressure (-1.4 mm Hg), maintenance of low-density lipoprotein cholesterol (LDL-C) (0.9 mg/dL), and increases in high-density lipoprotein cholesterol (HDL-C) (2.3 mg/dL) were observed in the BSG group at week 8 but significance was not achieved. Conclusions Consuming 10.4 g BSG daily for 8 weeks increases dietary fiber intake and is well tolerated when habitually consumed but does not significantly impact blood biomarkers of CVD risk, body composition, or blood pressure in healthy adults. Participant health status, BSG dosage, and study design may be key determinants of outcome measures and should be further evaluated in future studies. Funding Sources Jennifer Thomas Brown Memorial Nutrition Award and Moore-Khourie Award.