Isoelectric point isolation and characterization of proteins from lupine cultivars as influenced by chemical and thermal treatments

Use of supercritical CO2 to improve the quality of lupin protein isolate

Lupins are an excellent source of protein which can be used to obtain protein isolates with potential use in the food industry. Some studies use supercritical CO2 (SC-CO2) to defat legume flours, but no study analyzes the effect of applying this technology directly to the protein isolate. This article has proposed the use of SC-CO2 to improve lupin protein isolate (LPI) quality. SC-CO2 increased the LPI purity while reducing oil and other antitechnological factors (saponins and polyphenols). The treatment significantly improved the LPI color due to the elimination of the lipid fraction and lipophilic pigments (carotenoids). No changes in amino acid contents or chemical score were observed due to the SC-CO2. Finally, the treatment improved or did not affect the main LPI technofunctional properties. Therefore, SC-CO2 is a promising technique to enhance the quality of protein isolates, without affecting or improving their functional properties.

Effect of roasting temperature and soaking time on the nutritional, antinutrional and sensory properties of protein-based meat analog from lupine

White lupine is a legume crop rich in adequate valuable nutrient profiles especially used as a possible source of proteins where animal-based proteins are scarce. However, there is little documented information about the effect of processing conditions to produce lupine protein-based meat analog. This study explores the impact of roasting temperature (raw, 130, 140, and 150 °C) and soaking time (raw, 2, 4, and 6 days) on the chemical compositions, physical quality, and sensory attributes of meat analog. The result showed that roasting at 140 °C and soaking for 4 days significantly increased (p˂0.05) the proximate and mineral contents of the meat analog. The highest protein content (82.46 %) was obtained at T2t2 (roasted at 140 °C and soaked for 4 days). While the lowest protein content (62.47 %) was observed at T3t3 (roasted at 150 °C and soaked for 4 days). Similarly, the highest (93.17 %) and lowest (79.47 %) cooking yields were obtained at T2t2 and T3t3 respectively. Roasting and soaking conditions also showed a significant effect (p˂0.05) on the anti-nutrient contents of meat analog. The highest overall sensory acceptability (6.40) of the meat analog was observed at T2t2. The research suggests that suitable processing conditions can enhance the nutritional profiles of lupine protein-based meat analog, potentially enabling its industrial production and global market entry.

The application of ferritin in transporting and binding diverse metal ions

The ferritin cage can not only load iron ions in its inner cavity, but also has the capacity to carry other metal ions, thus constructing a new biological nano-transport system. The nanoparticles formed by ferritin and minerals can be used as ingredients of mineral supplements, which overcome the shortcomings of traditional mineral ingredients such as low bioavailability. Moreover, ferritin can be used to remove heavy metal ions from contaminated food. Silver and palladium nanoparticles formed by ferritin are also applied as anticancer agents. Ferritin combined with metal ions can be also used to detect harmful substances. This review aims to provide a comprehensive overview of ferritin's function in transporting and binding metal ions, and discusses the limitations and future prospects, which offers valuable insights for the application of ferritin in mineral supplements, food detoxifiers, anticancer agents, and food detections.

Optimization and Characterization of Lupin Protein Isolate Obtained Using Alkaline Solubilization-Isoelectric Precipitation

The trend in today's society is to increase the intake of vegetable protein instead of animal protein. Therefore, there is a concern to find new sources of alternative protein. In this sense, legumes are the main protein source of vegetable origin. Of all of them, lupins are the ones with higher protein content, although they are currently undervalued as an alternative for human consumption. In this sense, it is vital to characterize and obtain protein isolates from this legume, which satisfies the growing demand. Therefore, in the present work, the procedure for obtaining a lupin (Lupinus luteus) protein isolate (LPI), based on basic solubilization followed by isoelectric precipitation, has been optimized and validated. The optimized LPI, as well as the lupin flour, were subsequently characterized. The chemical composition, physicochemical, as well as the technofunctional properties of the LPI were analyzed. The results show that the proposed procedure had a high yield (23.19 g LPI/100 g flour) and allowed to obtain high-purity protein isolates (87.7 g protein/100 g LPI). The amino acid composition and the chemical scores show high proportions of essential amino acids, being protein deficient only in methionine and valine. Therefore, it can be affirmed that it is a high-quality protein that meets the requirements proposed by the FAO. Regarding the lipid fraction, it is mainly composed of unsaturated fatty acids (C18:1n-9 and C18:2n-6), which is also advisable in order to follow a healthy diet. Finally, LPI showed interesting technofunctional properties (foaming, gelling, emulsifying, water and oil absorption, and solubility), which makes it especially attractive for use in the food industry.