Technical Yearbook 2024

OCTOBER

PIXABAY

potato juice from chips represent the most homogeneous group. These co belonging to the glycoprotein family, have a molecular mass of about 40KD isoelectric point between 4.5 and 5.2. At neutral pH and room temperature dimer stabilised by hydrophobic forces. Changes in pH significantly affect dimensional structure, and temperature above 60°C easily causes its dena Solubility differences between plant-based proteins and animal prote It is important to note that plant proteins are only partially soluble, unlike an Due to reactivity related to the surface characteristics of the particles, a hig the product will carry out its effect in suspension. Figure 1 shows the suspe two plant-based proteins at pH 3.5.

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Plant-based proteins in oenology By Gianni Triulzi, Alessandra Basana & Pietro Bighiani

FIGURE 1. Proteins hydrated to 5% in water at pH 3.5. A – pea protein, B Figure 2 shows results from SDS-PAGE electrophoresis of potato and pea protein is characterised by a predominant band corresponding to about 40 while pea protein consists of many protein fragments distributed in the 10 range.

The use of proteins in winemaking About two thousand years ago, the Romans transformed wine from a drink for a select few to ‘mass nourishment and pleasure’, spreading it to every corner of the empire. The enormous increase in the volumes produced required a better production process, as the average quality of what was marketed was often questionable. juice from chips represent the most homogeneous group. These compounds, ng to the glycoprotein family, have a molecular mass of about 40KDa and an tric point between 4.5 and 5.2. At neutral pH and room temperature, patatin is a stabilised by hydrophobic forces. Changes in pH significantly affect its three ional structure, and temperature above 60°C easily causes its denaturation. lity differences between plant-based proteins and animal proteins portant to note that plant proteins are only partially soluble, unlike animal proteins. reactivity related to the surface characteristics of the particles, a high percentage of duct will carry out its effect in suspension. Figure 1 shows the suspension of the nt-based proteins at pH 3.5. M To this end, in addition to blending, which was well-known and used at the time, numerous winemaking practices were developed that improved the quality of the wines. Among the many practices used was the treatment with milk, eggs or albumin and wild pea flour. These applications represent the ancestors of today’s clarification practices.

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FIGURE 2. Electrophoretic profile of the soluble fraction of potato (A) and pea (B) proteins. (M) molecular weight markers.

100 E 1. Proteins hydrated to 5% in water at pH 3.5. A – pea protein, B – potato protein. 2 shows results from SDS-PAGE electrophoresis of potato and pea proteins. Potato is characterised by a predominant band corresponding to about 40 KDa (patatin), ea protein consists of many protein fragments distributed in the 10 - 100 KDa FIGURE 1. Proteins hydrated to 5% in water at pH 3.5. A – pea protein, B – potato protein. TECHNICAL YEARBOOK 2024