Effects of spraying surfactants in a fluidised bed on the rehydration behaviour of milk protein isolate powder

Commercial Production of Highly Rehydrated Soy Protein Powder by the Treatment of Soy Lecithin Modification Combined with Alcalase Hydrolysis

The low rehydration properties of commercial soy protein powder (SPI), a major plant-based food ingredient, have limited the development of plant-based foods. The present study proposes a treatment of soy lecithin modification combined with Alcalase hydrolysis to improve the rehydration of soy protein powder, as well as other processing properties (emulsification, viscosity). The results show that the soy protein-soy lecithin complex powder, which is hydrolyzed for 30 min (SPH-SL-30), has the smallest particle size, the smallest zeta potential, the highest surface hydrophobicity, and a uniform microstructure. In addition, the value of the ratio of the α-helical structure/β-folded structure was the smallest in the SPH-SL-30. After measuring the rehydration properties, emulsification properties, and viscosity, it was found that the SPH-SL-30 has the shortest wetting time of 3.04 min, the shortest dispersion time of 12.29 s, the highest solubility of 93.17%, the highest emulsifying activity of 32.42 m2/g, the highest emulsifying stability of 98.33 min, and the lowest viscosity of 0.98 pa.s. This indicates that the treatment of soy lecithin modification combined with Alcalase hydrolysis destroys the structure of soy protein, changes its physicochemical properties, and improves its functional properties. In this study, soy protein was modified by the treatment of soy lecithin modification combined with Alcalase hydrolysis to improve the processing characteristics of soy protein powders and to provide a theoretical basis for its high-value utilization in the plant-based food field.

Ingredients, structure and reconstitution properties of instant powder foods and the potential for healthy product development: a comprehensive review

Instant foods are widely presented in powder forms across different food segments, which potentially can be formulated with functional or beneficial compounds to provide health benefits. Many reconstituted instant powder foods form colloidal suspensions with complex structures. However, designing instant powder food could be challenging due to the structural complexity and high flexibility in formulation. This review proposed a new classification method for instant powder foods according to the solubility of ingredients and the structure of the reconstituted products. Instant powder foods containing insoluble ingredients are discussed. It summarised challenges and current advances in powder treatments, reconstitution improvement, and influences on food texture and structure to facilitate product design in related industries. The characteristics and incorporation of the main ingredients and ingredients with health benefits in product development were reviewed. Different products vary significantly in the ratios of macronutrients. The macronutrients have limited solubility in water. After being reconstituted by water, the insoluble components are dispersed and swell to form colloidal dispersions with complex structures and textures. Soluble components, which dissolve in the continuous phase, may facilitate the dispersing process or influence the solution environment. The structure of reconstituted products and destabilising factors are discussed. Both particle and molecular structuring strategies have been developed to improve wettability and prevent the formation of lumps and, therefore, to improve reconstitution properties. Various types of instant food have been developed based on healthy or functional ingredients and exhibit positive effects on the prevention of non-communicable diseases and overall health. Less processed materials and by-products are often chosen to enhance the contents of dietary fibre and phenolic compounds. The enrichment of phenolic compounds, dietary fibres and/or probiotics tend to be simultaneous in plant-based products. The process of the ingredients and the formulation of products must be tailored to design the desired structure and to improve the reconstitution property.

Physical, Morphological, and Rheological Properties of Agglomerated Milk Protein Isolate Powders: Effect of Binder Type and Concentration

Milk protein isolate powder (MPIP), a high protein-based powder, is a common dietary ingredient but has poor physical properties due to its cohesive nature. Powder agglomeration is one of the most widely used methods to improve and modify the quality of MPIP structures. In this study, the physical, morphological, and rheological properties of MPIPs agglomerated in a fluidized-bed agglomeration process were investigated as a function of sugar binder type and concentration. The physical properties of MPIP were evaluated by their flowability, cohesiveness, porosity, particle size distribution (PSD), and water-holding properties (wettability, solubility, and water-binding capacity). The density values of the agglomerated MPIPs decreased with increasing the binder concentration, whereas the porosity, wettability, and solubility values increased. Such trends were consistent with SEM observations. The MPIP agglomerated with 10% sorbitol had the largest particle diameter (D₅₀) and showed better physical properties compared to the other sugar binders. The viscosity values (η_a,50) of the MPIPs agglomerated with sugar binders showed lower values than the control (no sugar binder). The agglomeration process enhanced the viscoelasticity of the MPIP, but the viscoelasticity decreased with increasing the sugar binder concentration. These observations suggested that the physical, morphological, and rheological properties of MPIP can be greatly affected by the binder type and concentration in the agglomeration process.

Effect of Fluidized Bed Agglomeration on Rheological and Physical Properties of Soy Protein-Enriched Milk Powder for Dietary Supplementation in Sarcopenia

Recently, many elderly people in Korea have been consuming protein-enriched milk powders for dietary supplementation in sarcopenia. In general, protein powders are manufactured using a spray dryer, and their fine particles result in poor instant properties. Fluidized bed agglomeration (FBA) is an effective method for improving the physical properties of protein powders via particle granulation, such as flowability and wettability. Therefore, the effects of FBA on the rheological and physical properties of isolated soy protein (ISP)-enriched skim milk powder (SMP) were investigated in this study. The size of ISP-enriched SMP particles was significantly increased by FBA, leading to changes in the Carr index and Hausner ratio from fair flowability and intermediate cohesiveness to good flowability and low cohesiveness, respectively. The wettability of the granulated particles was also improved by FBA, and they exhibited a shorter wetting time below 10 s. However, a slight color change was observed after the FBA process. These findings contribute to the production of protein-enriched food powders with improved properties.

Updating insights into the rehydration of dairy-based powder and the achievement of functionality

Dairy-based powder had considerable development in the recent decade. Meanwhile, the increased variety of dairy-based powder led to the complex difficulties of rehydrating dairy-based powder, which could be the poor wetting or dissolution of powder. To solve these various difficulties, previous studies investigated the rehydration of powder by mechanical and chemical methods on facilitating rehydration, while strategies were designed to improve the rate-limiting rehydration steps of different powder. In this review, special emphasis is paid to the surface and structure of the dairy-based powder, which was accountable for understanding rehydration and the rate-limiting step. Besides, the advantage and disadvantage of methods employed in rehydration were described and compared. The achievement of the powder functionality was finally discussed and correlated with the rehydration methods. It was found that the surface and structure of dairy-based powder were decided by the components and production of powder. Post-drying methods like agglomeration and coating can tailor the surface and structure of powder afterwards to obtain better rehydration. The merit of the mechanical method is that it can be applied to rehydrate dairy-based powder without any addition of chemicals. Regarding chemical methods, calcium chelation is proved to be an effective chemical in rehydration casein-based powder.