Affiliation:
1. NEVSEHIR HACI BEKTAS VELI UNIVERSITY
Abstract
This research was carried out to determine the pH, titratable acidity, ash, specific gravity, color (L*, a*, b*), water activity, electrical conductivity, glass transition temperature (Tg) and melting characteristics of grape and mulberry pekmez samples adulterated with different levels (10%, 30%, 50%) of high fructose corn syrup (HFCS). Ash, titratable acidity and electrical conductivity values have decreased significantly (P<0.05) with the level of adulteration and determined that these properties can be used as a criterion in the determination of adulteration. Two glass transition temperatures occurring between -25.64℃ to -32.58℃ (Tg1) and 23.29℃ to 31.22℃ (Tg2) were detected in all pekmez samples. The single glass transition temperature was determined in the pekmez samples diluted with water, and both the glass transition temperatures and the onset, peak, end temperatures and enthalpy values of the melting peaks increased significantly with the increase in the amount of adulteration (P<0.05).
Publisher
Association of Food Technology, Turkey
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