Exploration of the chemical composition and physical properties of dried bakery products from six different processing plants in the United States

Dried bakery products are produced using several different input materials derived from baked goods, breakfast cereals, tortillas, and confections, depending on the geography and regional producers. Therefore, the physical characteristics and nutrient composition can vary between processing plants and need further characterization. This study aimed to evaluate the nutritional composition and physical characteristics of DBP samples from six industrial processing plants across the United States (Maryland, Texas, Georgia, Kansas, and California), collected on six different production days. Dry matter (DM; 89.5% to 90.6%), crude protein (9.4% to 13.6%), crude fat (8.0% to 12.6%), and total dietary fiber (TDF; 6.9% to 20.6% DM) varied (<i>P</i> < 0.05) among DBP produced in different plants, with TDF presenting the greatest variability among these nutrients. Similarly, long-chain fatty acids, mineral concentrations (except iron and copper), and starch characteristics also differed (<i>P</i> < 0.05) among samples. Although variability was observed among plants as hypothesized, all DBP samples were considered a good source of starch (46% to 54% DM). Most of the starch was gelatinized (32% to 41% DM) and rapidly digestible (39.7% to 48.0% DM), with samples containing less than 1% resistant starch. Differences (<i>P</i> < 0.05) in the density, flow indicators, aeration energy, shear, and wall friction properties of the DBP samples were observed. Samples from DBP-California-2 and DBP-California-1 were the most flowable under dynamic and aerated flow conditions. Both DBP-Maryland and DBP-Texas were the most free-flowing and least resistant to sliding against a metal surface from a compressed state among the locations tested. These findings highlight the variability of DBP across processing facilities and demonstrate its potential as an energy and fiber source in livestock and companion animal diets.