Influence of Different Enzymes during the Frozen Storage of Pre-Baked French Bread Elaborated with Whole-wheat Flour

摘要

This study evaluated the effect of frozen storage on the quality of pre-baked French bread elaborated with whole-wheat flour, determining whether rolls containing different concentrations of the enzymes glucolipase, hemicellulases and hexose oxidase presented any differences during thus period. Three different formulations were evaluated after 0, 1, 7, 15, 30 and 65 days of frozen storage. Specific volume, springiness and sensory evaluation of re-baked rolls practically did not change with the frozen storage period. After 1 day of frozen storage, the firmness of the re-baked rolls reduced (33.11 gf on average) and remained unchanged until 65 days. The frozen pre-baked rolls did not have difference during frozen storage for differential scanning calorimetry parameters of the starch transitions and for unfreezable water content (33–50% of the total water). The enzymes affected the specific volume, firmness, springiness of re-baked rolls and also the moisture of pre-baked breads thought the frozen storage period. Practical Applications The Dietary Guidelines for Americans 2010 (U.S. Department of Agriculture and U.S. Department of Health and Human Services 2010) recommends refined grains should be replaced with whole grains, such that at least half of all grains eaten are whole grains. Despite this recommendation, it is difficult to insert whole grains in processed foods such as pre-baked bread, because of technological difficulties arise. Moreover, various problems can occur during the frozen storage of pre-baked bread rolls under controlled freezing conditions for a prolonged period of time. Various additives are used to improve the dough properties and bread quality in the bakery industry and currently enzymes play an important role in baking technology. Therefore, three different enzymes were used in this study. The interference on bread quality during frozen storage depended on the presence/absence or the amounts of the enzymes in the roll formulation. This shows that the formulation is an important factor to be considered in pre-baked bread stored at freezing temperatures.