Investigation of the effects of ozone gas application to wheats on the chemical composition, rheological and textural properties and sensory quality parameters of raw material, dough and bread

Cereals have been a fundamental part of human nutrition throughout history, with wheat serving as a primary food source both in Turkey and worldwide. According to data from the Food and Agriculture Organization of the United Nations (FAO), approximately 1.3 billion tons of food is either lost or wasted globally every year. Post-harvest losses in cereals account for about 55%, with 10-40% of these losses attributed to storage pests. During storage, the activity of pests and the growth of molds such as Aspergillus, Penicillium, and Fusarium species frequently lead to mycotoxin contamination. Chemical agents like permanganate, chlorine dioxide, and fluorine are commonly used in the food industry to prolong the shelf life of cereals.However, these substances can produce harmful by-products, such as trihalo compounds, posing risks to human health and food safety. In contrast, increasing demand for natural and healthy food has emphasized the use of ozone, a "green technology," as an alternative solution. This study evaluated the effects of ozone treatment at different concentrations (14, 37, and 65 ppm) and durations (45, 90, and 150 min.) on three bread wheat varieties with varying protein content (strong, medium, and weak). The impact of ozone on AFB1 detoxification was examined, and the optimal parameters (65 ppm for 150 min.) were identified. Wheat samples treated under these conditions were analyzed for physical (grain weight, hectoliter weight, color) and chemical properties (protein, moisture, ash, total phenolic content, and total antioxidant activity). Physicochemical characteristics, 8 including Zeleny sedimentation, wet gluten content, gluten index, and falling number, were also assessed. Rheological properties were evaluated using farinograph, extensograph, and rheometer analyses, while bread quality was analyzed in terms of weight, volume, specific volume, and texture. Starch properties were examined through diferential scanning calorimetry (DSC) analysis, and oxidative changes in protein and starch structures were assessed with scanning electron microscopy (SEM) imaging and fourier transform infrared spectroscopy (FT-IR). The results indicated that ozone treatment caused no significant changes in total protein, ash, or dry matter content. Zeleny sedimentation values decreased in strong wheat, slightly decreased in medium wheat, and remained unchanged in weak wheat. Wet gluten content was unaffected in strong and medium wheat but decreased in weak wheat. Gluten index increased in strong wheat but decreased in weak wheat. Falling number values increased across all wheat varieties. Ozone generally improved dough rheological properties depending on the wheat variety, while bread analyses showed no significant changes. SEM and FT-IR analyses revealed distinct oxidative modifications in protein and starch structures caused by ozone treatment.