Use of dried pumpkins in wheat bread production

Abstract

Pumpkins belong to the family of Cucurbitaceae. They are classified to Cucurbita pepo, Cucurbita moschata, Cucurbita maxima and Cucurbita mixta, according to the texture and shape of their stems. The nutritional value of pumpkin fruits is high, varies from one species or cultivar to another. Pumpkins are reach in vitamins C, B1, B6, K, and in mineral substances. There are no data found about vacuum microwave dried pumpkin application in wheat bread production. The main purpose of the research was to evaluate quality parameters of microwave vacuum dried pumpkins and to verify its application in wheat bread production. Following quality parameters of pumpkins and bread made with pumpkin additive were evaluated: moisture content (oven – drying method), vitamin C content (iodometric), carotenoid content (spectrophotometric), reducing sugars (LVS 252:2000), colour changes (ColorTec- PCM), total fat content (ISO 6492:1999), degree of bread liking (ISO 4121:2003), bread baking loss and dry off. Quality parameters of non dried pumpkins were: content of reducing sugars − 2.40 g⋅100 g-1, vitamin C – 0.26 g⋅100 g-1, carotenoids – 0.50 mg % (in dry matter). The technological parameters for pumpkins drying in vacuum microwave drier were used: pressure (70–50 mmHg), speed of tumbler – 6 rpm, one working cycle and three stages. During the pumpkins drying process a decrease in the following parameters was observed: moisture content – 10.5 times, vitamin C content – 2.0 times; increase of yellowness (b*) value – 1.5 times. The optimal dried pumpkin additive to the wheat dough was 10% of the total flour amount. The wheat bread sample with dried pumpkins additive is richer in carotenoids and reducing sugars comparing to control wheat bread sample. The results of sensory analyses using hedonic rating demonstrated that a higher degree of liking was attributed to the bread sample with dried pumpkins additive (7.3) comparing to control wheat bread sample (6.7).