Browning indicators in bread

Bread is the most important food in the Spanish household and represents th e largest proportion of products produced by commercial bakeries. The brown ing indicators furosine, hydroxymethyl-furfural (HMF), and color were deter mined to evaluate heat effects induced during manufacture of these foods. T he breads analyzed were common, special, sliced toasted, and snack breads. Identical sample preparation and HPLC conditions were used to determine HMF in all breads. The precision tested at high and low HMF concentration in b reads was 2.60% and 1.57%, respectively. Recovery of HMF was 96.2%. The HMF values ranged from 2.2 to 68.8 mg/kg. Color index (100 - L*) ranged from 1 7.0 to 38.2. The linear correlations (r(2)) between 100 - L*/HMF were above 0.70 for common, special, and snack breads. Similar correlation was obtain ed between 100 - L*/HMF in a dough baking at different times. The furosine content in common bread ranged between 125 and 208 mg/100 g of protein. No linear correlation was found between furosine and HMF. Moreover, HMF and fu rosine were also determined in crumb and crust. Levels of HMF had a wide ra nge (0.9-1.76 mg/kg) and furosine was between 43 and 221 mg/100 g of protei n.