نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 دانشکده صنایع غذایی، گروه آموزشی علوم و صنایع غذایی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
2 استاد، گروه علوم و صنایع غذایی، دانشکده صنایع غذایی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
3 دانشیار، گروه علوم و صنایع غذایی، دانشکده صنایع غذایی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objectives: Plant proteins are predominantly globular storage proteins with high molecular weight. Their application in food formulations is often restricted by their rigid structure, which leads to poor solubility, weak emulsifying ability, and limited foaming capacity. Consequently, efficient strategies to tailor the structure of plant proteins are required to enhance their functionality and expand their industrial applications. In recent years, the Maillard reaction has been widely recognized as a natural and safe approach for conjugating proteins with carbohydrates, enabling structural modification under controlled conditions without the use of chemical additives. This study aimed to prepare and investigate the structural and functional properties of conjugates derived from pumpkin seed protein isolate and the soluble fraction of Persian gum at different ratios (1:1, 1:3, and 3:1). The findings of this study could facilitate the development of novel functional ingredients with broad applications in the food industry.
Materials and Methods: Pumpkin seed protein isolate-Soluble fraction Persian gum conjugates were prepared via the dry heating method at 60 °C and 75% relative humidity for 48 h at protein-to-gum ratio of 1:1, 1:3, and 3:1. The degree of conjugation or substitution of free amino groups during the Maillard reaction was quantified using the ortho-phthalaldehyde (OPA) method. Fourier transform infrared (FTIR) spectroscopy and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) were performed to confirm the occurrence of the Maillard reaction. Additionally, color parameters, emulsifying properties (emulsifying activity index and emulsion stability), particle size, zeta potential of emulsions, and foaming properties (foaming capacity and foaming stability) were evaluated.
Results: Covalent interactions between Pumpkin seed protein isolate– Soluble fraction Persian gum via the Maillard reaction were confirmed by OPA analysis, FTIR spectra, and SDS-PAGE profiles. Among the different ratios, the 1:3 Pumpkin seed protein isolate– Soluble fraction Persian gum conjugate exhibited the highest zeta potential (−41.35 ± 0.81 mV), emulsifying activity (14.19 ± 0.18 m²/g), emulsion stability (67.57 ± 1.52%), foam capacity (36.23 ± 0.23%), and foam stability (27.53 ± 1.01%) (p ≤ 0.05). These results were consistent with the highest degree of conjugation observed for this ratio. In general, the results of different evaluations showed that the produced conjugates exhibited better functional properties compared with the native protein.
Conclusion: Conjugation of pumpkin seed protein isolate with the soluble fraction of Persian gum via the Maillard reaction significantly enhanced emulsifying and foaming properties, as well as modified particle size and zeta potential of the resulting emulsions, compared to the unmodified protein. This process yields protein–polysaccharide structures with improved functional properties, which can be effectively incorporated into a wide range of food products, including beverages, bakery items, and dairy products.
کلیدواژهها [English]
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