PH-değişim metodunun soya protein konsantresinin çözünürlüğü ve emülsiyon özellikleri üzerine etkisi

Bu çalışmanın amacı, pH değişiminin soya protein konsantresinin fonksiyonel özelliğini artırmaya yönelik etkisini araştırmaktır. Bu çalışmada, soya protein konsantresinin pH değeri, nötr pH (pH 7)’dan önce sırasıyla pH 2, 3, 4, 5, 10, 11, ve 12’ye ayarlanmıştır. pH-değişim işlemi, soya protein konsantresinin çözünürlüğünü etkili bir şekilde artırırken, bu artış asidik koşullar altında muamele edilen numunelerde daha az gözlenmiştir. Alkalin pH değerleri (pH 10, 11 ve 12), asidik pH değerlerine (pH 2, 3 ve 4) kıyasla daha yüksek çözünürlük göstermiştir. pH 12 ile muamele edilen örneklerde yaklaşık 30 kat daha fazla çözunürlük elde edilmiştir. Örnekler arasında, pH 12 ile muamele edilen numuneler en yuksek emülsiyon aktivite ve stabilite değerlerini göstermişlerdir. Farklı pH değerleriyle muamele edilen örneklerin hepsi, asidik veya alkalin olmasına bakılmaksızın, kontrol örneklerine kıyasla daha küçük parçacık boyutu ve daha az bir bulanıklık sergilemişlerdir.

Anahtar Kelimeler:

pH değişim, Çözünürlük, Soya protein konsantresi, Emülsiyon özellikleri, Parçacık boyutu

Effect of pH-shifting method on solubility and emulsifying properties of soy protein concentrate

The purpose of the current study was to investigate the influence of pH shifting process on soy protein concentrate to improve its functional properties. In this work, pH of the soy protein concentrate was adjusted to pH 2, 3, 4, 10, 11, and 12 prior to neutral pH (pH 7). pH-shifting process effectively improved the solubility of soy protein concentrate, whereas the modification of the samples with the acidic conditions was less pronounced. The alkaline pH values (pH 10, 11, and 12) showed higher solubility compared to the acidic pH values (pH 2, 3, and 4). With the pH 12 treatment, approximately 30 times higher solubility was achieved. Among the treatments, the pH 12- treated samples showed the improved emulsifying properties with the highest emulsifying activity and stability indexes. All pH treated samples (pH 2, 3, 4, 10, 11, 12) showed less turbidity with smaller particle sizes where the untreated samples showed most turbid structure with the biggest particle size.

Keywords:

pH-shifting, Solubility, Soy protein concentrate, Emulsifying properties, Particle size,

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