Pisilyum tozu ilavesinin taze ve dondurulmuş glutensiz ekmek kalitesi üzerine etkisinin araştırılması

SEVDA CAN KEMAN

Pisilyum tozu ilavesinin taze ve dondurulmuş glutensiz ekmek kalitesi üzerine etkisinin araştırılması

Thesis Type: Postgraduate

Institution Of The Thesis: Yıldız Technical University, Graduate School of Natural and Applied Sciences, GIDA MÜHENDİSLİĞİ ANABİLİM DALI, Turkey

Approval Date: 2024

Thesis Language: Turkish

Student: SEVDA CAN KEMAN

Supervisor: Görkem Özülkü

Open Archive Collection: AVESIS Open Access Collection

Abstract:

Psyllium (Plantago ovata) is widely used in gluten-free product formulations due to its water-binding and gel-forming properties. One of the main problems of gluten-free bread production is that staling faster than wheat flour bread. In this study, frozen dough technology was used to offer fresh bread to consumers on a gluten-free diet. In this context, the effect of using psyllium powder (PP) in the production of frozen gluten-free bread on the fundamental rheological properties of dough and the quality characteristics (specific volume, texture and color) of breads was investigated. When compared to the control sample (0% PP), the addition of PP (7.5% and 15%) into the gluten-free dough decreased the tan δ value which is an indicator of the dough viscoelasticity (p<0,05). No significant effect on tan δ value of the doughs containing PP was observed during frozen storage (−30 °C, 7, 15 and 30 days) (p ≥0.05) while the tan δ value of the control sample decreased significantly (p<0,05). Higher specific volume and lower bread crumb hardness were obtained in gluten-free breads with PP addition (p<0,05). Specific volume of control and the bread containing 7.5% PP decreased significantly at the end of frozen storage (−30 °C, 30th day) compared to fresh samples (p<0,05). Frozen storage did not affect the specific volume value of breads with 15% PP addition (p ≥ 0.05). The crust and crumb lightness value (L*) of fresh breads decreased compared to the control sample, depending on the amount of PP (p<0,05). At the end of frozen storage, gluten-free breads containing PP had higher specific volume and lower bread crumb hardness than control sample. In addition, volatile component analysis was performed on bread samples and the change in the amount and variety of components with freezing preservation was observed. As a result of the volatile component analysis performed on bread samples, the most volatile components were detected in the gluten-free control bread (11 pieces), and the least volatile component was detected in the gluten-free bread with 15% PT addition (5 pieces). Commonly detected for all bread types were ethanol and 1-butanol, 3-methyl from the alcohol group, and butanal, 3-methyl and hexanal from the aldehyde group. It was observed that 7.5% PT added gluten-free bread preserved its textural properties in freezing compared to other samples and was more suitable for 15-day storage. According to the results obtained, it was concluded that psyllium can also be used in the production of frozen gluten-free bread.