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

Year 2019, , 159 - 166, 18.06.2019

Gülçin Yıldız

https://doi.org/10.29050/harranziraat.427438

Cited By: 7

Abstract

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

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

Abstract

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.

Keywords

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

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