Okara Promoted Acrylamide and Carboxymethyl-lysine Formation in Bakery Products

Abstract

Soybeans are widely used in bakery products because of their technological advantages and, recently, soybean-containing products have been marketed as functional foods thanks to several health benefits. Okara is a soybean-based ingredient obtained after elimination of the water-soluble component from ground soybeans. In this paper the effect of okara addition to bakery products on the formation of some potentially harmful Maillard reaction products was evaluated. Cookies obtained by replacing 15% of wheat flour with okara showed a visible browning increase and a more intense Maillard reaction development as shown by higher concentrations of 5-hydroxymethyl-2-furaldehyde (HMF) (+100%), acrylamide (+60%), and carboxymethyl-lysine (CML) (+400%) with respect to the control. This phenomenon could be related to the presence in okara of about 50% of insoluble dietary fiber: the fiber reduces water activity during cooking, thus promoting Maillard reaction. To confirm this hypothesis, cookies obtained by replacing 7% of wheat flour with three different types of dietary fiber (cellulose, chitosan, and pea fiber) were prepared: these experimental cookies showed higher Maillard reaction product concentration with respect to the control and, in particular, HMF and CML values were directly related to the fiber water-holding capacity (WHC). To extend the observation to the food market, a sampling of soybean-containing commercial bakery products was analyzed by comparing the concentrations of Maillard reaction products with those of similar bakery products without soy. Soybean-containing samples showed higher concentrations of acrylamide and CML than corresponding controls.

Acrylamide: inhibition of formation in processed food and mitigation of toxicity in cells, animals, and humans

“…59 A study on the effects of baking conditions of cookies on the formation of acrylamide, N ε -(carboxymethyl)-lysine (CML) and antioxidative activity found that: (a) the highest level of acrylamide (328.9 μg kg −1 ) was present in cookies baked at 155°C for 21 min and at 205°C for 11 min (329.3 μg kg −1 ); (b) the highest level of CML (118.0 μg kg −1 ) was present in cookies baked at 230°C for 1.5 min; and (c) the antioxidative activity increased under the more severe baking conditions, suggesting that optimizing the baking temperature was not enough for making high-quality cookies. 60 This study also reported that soybean-containing commercial bakery products had higher concentrations of acrylamide and CML than corresponding controls, suggesting that adding soybean to wheat flour to enhance nutritional quality could adversely affect the safety of the baked products. 60 This study also reported that soybean-containing commercial bakery products had higher concentrations of acrylamide and CML than corresponding controls, suggesting that adding soybean to wheat flour to enhance nutritional quality could adversely affect the safety of the baked products.…”

Acrylamide in Soybean Products, Roasted Nuts, and Dried Fruits

“…The cooking process takes place within the extruder where the material produces its own friction and heat due to the pressure generated. Significantly higher acrylamide concentration (118.77 ng/g) was found in extruded soybean analyzed by Palermo et al [29]. However, the heating temperature appeared to have a greater effect on the acrylamide formation during extrusion.…”

“…However, according to Palermo et al [29] okra cookies were found to have significantly higher acrylamide concentrations (588.84 ng/g) compared to that in wheat cookies (361.88 ng/g). However, according to Palermo et al [29] okra cookies were found to have significantly higher acrylamide concentrations (588.84 ng/g) compared to that in wheat cookies (361.88 ng/g).…”

“…Palermo et al [29] have analyzed the concentration of acrylamide in nine products containing soya, such as crisp bread, shortbread, wholemeal cookies, toasted bread, breakfast cereals, crackers, dry cookies, butter cookies, and cereal bars, and these results are compared with the values in the conventional products ( Table 1). Palermo et al [29] have analyzed the concentration of acrylamide in nine products containing soya, such as crisp bread, shortbread, wholemeal cookies, toasted bread, breakfast cereals, crackers, dry cookies, butter cookies, and cereal bars, and these results are compared with the values in the conventional products ( Table 1).…”

Effects of extrusion, infrared and microwave processing on Maillard reaction products and phenolic compounds in soybean

“…At a constant heating time and moisture content, increasing the temperature load increased significantly ( P < 0.05) the amount of acrylamide formed in soybean, reaching 62.62 ng g −1 during extrusion at 130 °C. A higher acrylamide concentration (118.77 µg kg −1 ) was found in extruded soybean flour analyzed by Palermo et al . The results of the present study indicate that heat generation and its transfer through the raw material, which are specific to each of the thermal processes, caused significant differences in behavior and concentration of heat‐induced contaminants in the soybean products.…”