Solubility and Emulsifying Properties of Soy Protein Isolates Modified by Pancreatin

Abstract

Soy protein isolates (SPI) with varying degrees of hydrolysis (DH of 7, 11, 15, 17%) were produced using pancreatin. The surface hydrophobicity indices of pancreatin hydrolyzed SPI (PSPI) (34.5, 34.9, 39. 1, and 40.7 for 7, 11, 15, 17% DH, respectively) were higher than that of SPI (10.5) and control SPI (CSPI) (12.5, 11.9, 12.9, and 12.6 for 10, 60, 120, and 180 min incubation, respectively). The solubilities of PSPI at pH 4.5 were 2.7, 9.1, 11.9, and 18.7%, for 7, 11, 15, and 17% DH, respectively, while the solubilities of SPI and CSPI at the same pH were about 1. 6%. Solubilities of PSPI at pH 7. 0 were > 90% for all DHs tested, while those of SPI and CSPI were 85%. The emulsifying activity index (EAI) of PSPI increased with increasing DH. PSPI with 15% DH had highest EAI (1. 122) which was higher (P < 0. 05) than those of SPI (0.550) and CSPI after 120 min incubation without enzyme (0.568). These results suggest that PSPI could be used as an ingredient for emulsified products and where high solubility at low pH is required.

Antioxidant activity ofVigna unguiculataL. walp and hard-to-cookPhaseolus vulgarisL. protein hydrolysates

“…Degree of hydrolysis values were higher than those reported for hydrolysis of legumes such as V. unguiculata (23.61%) with Alcalase 1 for 60 min (Espinosa, Chel, & Betancur, 2006), chickpea (27%) with Flavourzyme 1 for 180 min (Clemente, Vioque, Sa´nchez-Vioque, Pedroche, & Milla´n, 1999) and soy with pepsin for 60 min (11%) and 180 min (17%) (Qi, Hettiarachychy, & Kalapathy, 1997). In general, enzymes from microbial and fungal origins such as Alcalase 1 and Flavourzyme 1 have a higher catalytic activity compared to enzymes from gastric and intestinal origins like pepsin and pancreatin.…”

Nutritional and functional properties of Roselle (Hibiscus sabdariffa L.) seed protein hydrolysates

“…In the case of whey and casein proteins on the other hand, Van der ven et al (2002) found that although foam formation showed improvement after enzymatic hydrolysis and that foam stability was poorer than it was before modification. Findings by Qi et al (1997) suggest that pancreatin modified soy protein exhibited better emulsifying activity index than the original protein, making it a potential ingredient in the emulsified foods formulation.…”

Effects of Rice Bran Protein Hydrolysates on the Physicochemical Stability of Oil-in-Water Emulsions

“…Protein hydrolysates are promising candidate to be used as natural emulsifiers because of their safety, biodegradability, and producibility from renewable sources. Several recent studies have reported on the potent emulsifying activities of various protein hydrolysates, such as soy 5 , and potato 6 protein hydrolysates. Considering on the effects of protein hydrolysates on oxidative stability of emulsion model, however, the data are still limited.…”

“…In this work, RBPH with different degrees of hydrolysis DH were prepared, and their abilities to retard both of phase separation and lipid oxidation in soybean O/W emulsions were observed. RBPH with rather low DH less than 10 were studied in the present work because of the previously reported disadvantages of extensively hydrolyzed peptides, including bitter taste as well as inferior emulsifying, foaming, and antioxidant activities 5,16 .…”