Structural, functional properties of protein and characteristics of tofu from small-seeded soybeans grown in the Loess Plateau of China

The structural, functional properties of protein isolated from small-seeded soybeans were investigated and characteristics of tofu were studied. Small-seeded soybean protein had obvious α', α, β, acidic and basic subunits bands and two endothermic peaks (76.02-76.63℃ and 91.94-94.25℃). Small-seeded black soybean protein isolates (SBSPI) had more β-sheet (31.90-33.54%) structure, while small-seeded yellow soybean protein isolates (SYSPI) had more α-helix (18.89-20.72%) structure. SYSPI had higher fluorescence intensity (839.10-847.80) than SBSPI (482.70-565.10). SBSPI exhibited higher surface hydrophobicity (939.51-1252.75) and water absorption capacity (8.07-8.50 g/g). Tofu made from small-seeded yellow soybeans had higher yield (549.46-560.23 g/100 g soybean) and was brighter (L*, 74.61-77.48) and more yellowish (b*, 14.83-14.95) in color. Tofu made from Fugu small-seeded black soybean (FGSBS) had the highest hardness (178.52 g), adhesiveness (-25.77 g.sec), chewiness (87.45 g) and resilience (0.26), signifying a more compact structure.

Dynamic high pressure treatments: current advances on mechanistic-cum-transport phenomena approaches and plant protein functionalization

Dynamic high pressure treatment (DHPT) either by high pressure homogenization or microfluidisation, is an emerging concept used in the food industry for new products development through macromolecules modifications in addition to simple mixing and emulsification action. Mechanistic understanding of droplets breakup during high pressure homogenization is used to understand how these compact and high molecular weight-sized globular plant proteins are affected during DHPTs. Plant protein needs to be functionalized for advanced use in food formulation. DHPTs brought changes in plant proteins' secondary, tertiary, and quaternary structures through alterations in intermolecular and intramolecular interactions, sulfhydryl groups, and disulfide bonds. These structural changes in plant proteins affected their functional and physicochemical properties like solubility, oil and water holding capacity, gelation, emulsification, foaming, and rheological properties. These remarkable changes made utilization of this concept in novel food system applications like in plant-based dairy analogues. Overall, this review provides a comprehensive and critical understanding of DHPTs on their mechanistic and transport approaches for droplet breakup, structural and functional modification of plant macromolecules. This article also explores the potential of DHPT for formulating plant-based dairy analogues to meet healthy and sustainable food consumption needs. HIGHLIGHTSIt critically reviews high pressure homogenization (HPH) and microfluidisation (DHPM).It explores the mechanistic and transport phenomena approaches of HPH and DHPMHPH and DHPM can induce conformational and structural changes in plant proteins.Improvement in the functional properties of HPH and DHPM treated plant proteins.HPH and DHPM are potentially applicable for plant based dairy alternatives food system.

Improving the survival of Lactobacillus plantarum NRRL B-1927 during microencapsulation with ultra-high-pressure-homogenized soymilk as a wall material

Probiotic foods and supplements have been shown to offer multiple potential health benefits to consumers. Dried probiotic cultures are increasingly used by the food industry because they are easily handled, transported, stored, and used in different applications. However, drying technologies often expose probiotic cells to extreme environmental conditions that reduces cell viability. Hence, this study aimed to evaluate the effect of using ultra high-pressure homogenization (UHPH) on soymilk's microencapsulating ability, and the resultant effect on the survivability of probiotic Lactobacillus plantarum NRRL B-1927 (LP) during drying. Liquid suspensions containing LP (~10⁹ CFU/g of solids) were prepared by suspending LP cultures in soymilk which had been either treated with UHPH at 150 MPa or 300 MPa or left untreated. LP suspensions were then dried by concurrent spray drying (CCSD), mixed-flow spray drying (MXSD) or freeze-drying (FD). Cell counts of LP were determined before and after microencapsulation. Moisture, water activity, particle size and morphology of LP powders were also characterized. LP powders produced with 300 MPa treated soymilk had 8.7, 6.4, and 2 times more cell counts than those produced with non-UHPH treated soymilk during CCSD, MXSD, and FD, respectively. In the 300 MPa treated samples, cell survival (%) of LP during drying was the highest in MXSD (83.72) followed by FD (76.31) and CCSD (34.01). Using soymilk treated at higher UHPH pressures resulted in LP powders with lower moisture content, smaller particle sizes and higher agglomeration. LP powders produced via MXSD showed higher agglomeration and fewer signs of thermal damage than powders produced via CCSD. This study demonstrates that UHPH improves the effectiveness of soymilk as a microencapsulant for probiotics, creating probiotic powders that could be used in plant-based and non-dairy foods.

(Ultra) High Pressure Homogenization Potential on the Shelf-Life and Functionality of Kiwifruit Juice

The increasing competition within the food industry sector makes the requisite of innovation in processes and products essential, leading to focus the interest on the application of new processing technologies including high pressure homogenization (HPH) and ultra high pressure homogenization (UHPH). In this context, the present research aimed at evaluating the effects of two UHPH treatments performed at 200 MPa for 2 and 3 cycles on quality and functionality of organic kiwifruit juice stored at three different temperatures, i.e., 5, 15, and 25°C. The results showed that only the treatment performed at 200 MPa for 3 cycles was able to significantly increase the shelf-life of organic kiwifruit juices when stored at refrigeration temperature, avoiding also phase separation that occurred in the sample treated at 0.1 MPa (control) after 20 days of refrigerated storage. The obtained data showed also that the highest applied pressure was able to increase some quality parameters of the juice such as viscosity and luminosity (L^∗) and increased the availability of total phenol content consequently enhancing the juice total antioxidant activity. The application of a treatment at 200 MPa for 3 cycles allowed to obtain a stable kiwifruit juice for more than 40 days under refrigerated storage. A challenge to implement this technology in food process as full alternative to thermal treatment could be represented by the adoption of pressure level up to 400 MPa followed by the packaging in aseptic conditions.