| dc.description.abstract | Soy products such as tofu, are typically oriental, but despite their functional and nutritional properties, these foods are not consumed in the Brazilian diet, due to the characteristic odor and flavor. A possibility to change these attributes of tofu is the implementation of smoking, which was formerly used only as a method of preservation, but today is used to modify the sensory characteristics. The objective of this work was to develop and characterize smoked tofu. Soy beans were blanched, macerated, crushed and centrifuged to obtain soy extracts that were coagulated and pressed, thus obtaining the standard tofus, thereafter they were smoked at 42ºc, to obtain the smoked tofus. It was determined the amount of water absorbed in maceration of the grains, yield and proximal composition of soy extracts. The tofus were assessed in yield, proximal composition, color and sensory acceptance. When making tofu with soy BRS 232 and BRS 284 and coagulants CaSO4 and MgCl2 it was observed that soybean varieties and coagulators showed no influence in all parameters evaluated, only the coagulation time was greater when not homogenized in the mixture using CaSO4. There was no difference in levels of moisture, ash and protein in extracts of two soybean varieties used. In these smoked tofus the smoking process caused reduction in moisture content of 5.5% on average and dimming of these products, decreasing the luminosity L* values, and increasing the color red (higher values of a*) and yellow (higher values of b*), when compared with the standard tofus. Another experiment was performed using soybeans BRS 284 and calcium sulfate coagulant, where it was verified during the maceration grains absorbed 1.2 mL/g of water and the extract yield was higher, 79.92%, while that of tofu was lower, due to the pressing. The proximal composition of standard and smoked tofus showed no statistical difference. When evaluating the color of standard and smoked tofu, it was observed that there was statistical difference in all parameters evaluated (L*, a*, b*), as a consequence of smoking. The application of smoke in tofu caused better acceptance of the aroma, texture, flavor and global acceptance and also greater purchase intent by judges. Being that the texture of the smoked tofu was the attribute with greater acceptance by the evaluators. In experiment 2 was used soy BRS 232 and calcium sulfate coagulant, where the proximal composition were determined and the profile of isoflavones from soy beans and tofu were evaluated regarding the proximal composition, profile of isoflavones, colour, texture and sensory acceptance. In the soy beans the solid majority component is protein, and they were quantified six forms of isoflavones, but the forms glicitins and acetyl-β-glycosides were not detected and the aglicones were present in very low content. The standard and smoked tofus presented difference in moisture levels and lipids. The total value of isoflavones from tofus decreased in relation to grain, but there was an increase of approximately three times the content of aglicones. Smoking has changed the color of the tofu in the parameters a * and b * and also in brightness, representing the dimming smoked product. The texture profile analysis of standard and not smoked tofus presented statistical difference and the values obtained from these foods are cohesive, elastic and with acceptable hardness for the Brazilian market. In sensory analysis carried out by all the judges, the acceptance of the attributes color, aroma, texture, flavor and global acceptance of the tofus showed no significant difference, being that the averages of the notes were close to indifference in the range used. | |
