## 1 Introduction  
In some countries such as Mexico, 41.90% and 7.40% of the 130 million people live in poverty and extreme poverty, respectively [1]. These individuals lack the resources to acquire an adequate or permanent supply of foods, and therefore they generally have a low caloric intake and develop nutrient deficiencies, especially in terms of micronutrients and essential amino acids.  
Proteins provide the essential amino acids necessary for the construction and maintenance of tissues, organs, muscles, and antibodies, and therefore they are fundamental for the proper physical and mental development of children. Furthermore, the adequate intake of high-quality proteins allows for protection against infectious diseases and is, at the same time, an elementary unit for nutrition in adulthood [2]. Dietary proteins can be obtained from animal or vegetable sources.  
Vegetable proteins represent a low-cost energy source, but, unfortunately, not all of them fulfill highly digestible essential amino acids required for proper growth [3]. Their versatility depends on solubility, coagulation, emulsifying and foaming capacities (functional properties that limit their application in the food industry) [4].  
The type, size, structure and degree of hydrolysis of the protein fractions significantly influences their functionality [5]. Fractionation studies of soybean proteins show that glycinin (11S) is more soluble than other vegetable proteins. Glycinin provides more emulsifying activity and foam stability than \(\beta\)-conglycinin (7S), while the latter stimulates foaming and gelling activity [6; 7; 8].  
Legumes and cereals are excellent sources of proteins containing 18.5% to 50.0% and 6.0% to 18.0% of protein (db), respectively [9]. [PERSON] and [PERSON] characterized the physicochemical and functional properties of proteins from peas, lentils, navy beans and chickpeas, and determined that they have the potential to be applied in food due to their excellent functionality [9]. Legume proteins are deficient in methionine, cysteine, and tryptophan, contrary to the cereals where lysine and threonine are usually the limiting amino acids [10]. Commonly, vegetable proteins' amino acid deficiencies are improved through the combination or blending of legumes with cereals. [PERSON] et al. [11] optimized the nutrient content and protein quality of maize, sorghum, and millet combined with cowpeas, peanuts, or soybeans to supplement the diet in Ghana. Whereas [PERSON] et al. [12] mixed millet, rapoko and sorghum with soybeans and groundnuts to develop a high protein-energy cereal blend for the vulnerable population in Zimbabwe.  
Soybean is the legume with the highest protein content, with around 50%, while maize germ contains 18.4% [13]. Maize is a staple in the American continent and the most produced cereal worldwide. The combination of soybean with maize proteins represents an attractive alternative for elaborating nutritionally complete food products.  
This study's objective was to compare the physicochemical, functional, and nutritional characteristics of protein isolates and hydrolysates from soybean and soybean-maize mixes, exploring their use as a source of potential ingredients for the food industry.