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Salami, a well-known fermented meat product, is made from selected ground meat mixed with curing agents and spices. This work aimed to determine the viability of Lactiplantibacillus plantarum (as a starter), Lactobacillus acidophilus (probiotic microorganism), and their mixture during the fermentation and ripening of a salami-type product, evaluate the microbiological and physicochemical changes and assess the sensory acceptability of the final product. L. acidophilus has not been sufficiently explored as a probiotic in fermented meats, especially in terms of its effects on fermentation and sensory qualities. Salami-type products were formulated and fermented for 48 h at 32°C, and then ripening took place at 8°C for 13 days. pH, titratable acidity, Lactobacillus counts, and contaminating microbiota were analyzed during the process. Sensory evaluation was analyzed in the final products. The salami-type formulation served as an effective medium for growing microorganisms, with the populations of starter and probiotic cultures exceeding 10 8  CFU/g after fermentation and ripening for 15 days. The pH of the end products was ∼5.1, titratable acidity ∼2.5%, and aw ∼0.83. During fermentation and ripening, a significant reduction in total mesophilic aerobic bacteria (>7 logs), coliforms, and Staphylococcus aureus (>8-fold reductions) were observed. The sensory evaluation results indicate that the product's attributes are not influenced by the type of bacteria used, as no significant difference was found ( p > 0.05). The results show that L. acidophilus , Lactiplantibacillus plantarum , or their mixture can be used as a starter culture in fermented meat products. Using L. acidophilus , whether alone or in combination, is a viable option that preserves the characteristics of the fermented product and may enhance the benefits of probiotic consumption., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mani-López, Hernández-Figueroa, López-Malo and Morales-Camacho.)

Tomato seeds are a rich source of protein that can be utilized for various industrial food purposes. This study delves into the effects of using supercritical CO 2 (scCO 2 ) on the structure and techno-functional properties of proteins extracted from defatted tomato seeds. The defatted meal was obtained using hexane (TSMH) and scCO 2 (TSMC), and proteins were extracted using water (PEWH and PEWC) and saline solution (PESH and PESC). The results showed that scCO 2 treatment significantly improved the techno-functional properties of protein extracts, such as oil-holding capacity and foaming capacity (especially for PEWC). Moreover, emulsifying capacity and stability were enhanced for PEWC and PESC, ranging between 4.8 and 46.7% and 11.3 and 96.3%, respectively. This was made possible by the changes in helix structure content induced by scCO 2 treatment, which increased for PEWC (5.2%) and decreased for PESC (8.0%). Additionally, 2D electrophoresis revealed that scCO 2 hydrolyzed alkaline proteins in the extracts. These findings demonstrate the potential of scCO 2 treatment in producing modified proteins for food applications.

Edible insects are traditional foods worldwide, and in Mexico, is a prehispanic practice. Nowadays, edible insects can be a food source for the increasing population. This research aimed to evaluate the nutritional profile, physical and techno-functional characteristics of non-defatted (NDF) and defatted (DF) flour of the edible insect Arsenura armida to use as a functional ingredient. The lipid content in NDF was 24.18%. Both flours are high in protein, 20.36% in NDF and 46.89% in DF; their soluble proteins from A. armida were classified according to their molecular weight, which ranged from 12 to 94 kDa. The physical properties suggest that both flours have good flow characteristics. Regarding techno-functional properties, DF had the highest water (275.6%) and oil (121%) holding capacity values. The viscosity values indicate that they behave as a non-Newtonian shear-thinning fluid at a high concentration (20%). Emulsion capacity values range between 78.3 and 100% in both flours, with stability between 92.4 and 100%. These flours could be a good source of nutrients, and their techno-functional properties make them a good option for animal protein substitutes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Some studies aimed at revealing the relationship between protein structure and their functional properties. However, the majority of these reports have been carried out using protein isolates. There are limited reports on the possible relationship between the functional properties and the structure of a purified protein. In this work the amaranth 11S globulin acidic subunit (AAC) and five mutations of the same protein that were modified in their variable regions with antihypertensive peptides (VYVYVYVY and RIPP), were analyzed at two ionic strength (2.9 and 17.6 g/L NaCl) and pH (3.0-7.0). Results revealed better solubility for the proteins mutated at the terminal ends (AACM.1 and AACM.4) and lower solubility for the protein inserted with RIPP peptide. Spectroscopy studies revealed an increase of β-sheet structure at high salt concentration for all proteins. It was also observed that salt concentration acted as a modulator, which allowed a better foam features for all modified proteins limiting movement of side chains and reducing red-shifted displacement of λmax. All proteins showed foam capacity ranging from 76 to 93% although foam stability was twofold better for modified proteins than for AAC at high salt concentration. This study allowed better understanding about the structural changes that influence the foaming properties of engineered proteins.

Tomato ( Solanum lycopersicum ) is a widely consumed fruit all around the world. The industrial exploitation of tomato generates a lot of waste. Most of the utilization of tomato seeds waste is focused on animal feeding, as well as a food ingredient aimed to increase the protein content, and raw material for some organic bioactive component extraction. The aim of this work was to evaluate the techno-functional properties of tomato seed meal (TSM) and its nutraceutical properties after applying defatting processing (TSMD), and to evaluate the nutraceutical properties after a fermentation processing (TSMDF) by Lactobacillus sp. The results showed that, at alkaline conditions (pH 8-9), the techno-functional properties for TSM and TSMD improved. In comparison with TSM, TSMD showed higher water holding capacity (WHC ≈32%), higher oil holding capacity (OHC ≈13%), higher protein solubility (49-58%), more than 10 times foaming activity (FA), more than 50 times foam stability (Fst), as well as an improved emulsifying activity (EA) and emulsion stability (Est) wich were better at pH 9. Regarding the nutraceutical properties, after 48 h of fermentation (TSMDF), the antioxidant activity was doubled and a significant increase in the iron chelating activity was also observed. During the same fermentation time, the highest angiotensin-converting enzyme inhibition (ACEI) was achieved (IC50 73.6 μg/mL), more than 10 times higher than TSMD, which leads to suggest that this fermented medium may be a powerful antihypertensive. Therefore, the strategy proposed in this study could be an option for the exploitation of tomato wastes.

Hypertension is a worldwide health problem. It is the main cardiovascular risk factor and affects about 31% of the world's adult population. The drugs used to control hypertension may cause side effects; for this reason, there are many investigations focused on searching for alternatives to control or prevent this disease through diet. For example, many peptides have demonstrated antihypertensive effects. The insertion of bioactive peptides is a biotechnological implement used to improve the nutraceutical properties of proteins. This work reviews the current data on the insertion of antihypertensive peptides (AHPs) into food proteins, the systems used to produce the AHPs, the advantages and disadvantages between them, the parameters to produce them at major scales, and their potential applications in pharmacy and functional foods.

The insertion of peptides is a biotechnology tool widely used to improve the nutraceutical properties of proteins. Because the effect of these insertions in protein stability and function is difficult to predict, it should be determined experimentally. In this study, we created two variants of amarantin acidic subunit and analyzed them along with other four proteins reported previously. We measured their response against two destabilizing agents: temperature and urea. The six proteins presented the insertion of antihypertensive peptides (VYVYVYVY or RIPP) in the variable regions of the protein. We observed that their effect strongly depended on the site of the insertion. The insertion in the variable region I stabilized the protein both thermally and chemically, but it affected the inhibitory activity of the angiotensin-converting enzyme in vitro. In contrast, insertions in other three regions were severely destabilizing, producing molten globules. Our findings reveal that the insertion of bioactive peptides in variable regions of a protein can increase or decrease the protein's thermal and chemical stability and that these conformational changes may also alter its final activity.

In this research it was attempted to overexpress the acidic subunit, from the 11S amaranth seed globulin termed amarantin, modified with antihypertensive peptides in Escherichia coli Rosetta (DE3) by manipulating some factors in batch fermenter such as growth medium composition, inducer (isopropyl β-D-thiogalactopyranoside [IPTG] or lactose), air flow, cultivation temperature, agitation speed and induction time. The possibility of using several minimal media and lactose as inducer to increase yields of the recombinant protein was investigated. Previous fermentations at flask level showed that two minimal culture media (A6 and A7) and 0.5% (w/v) lactose presented high yields of the engineered protein expression. Thus, the latter two media were tested at fermenter level, the lactose inducer, and different environmental conditions. Factors with significant effects were identified by Plackett-Burman design with center points and were adjusted at the level suggested and the yields of the recombinant protein were increased from 303.2 to 1,531 mg L(-1) in A6 and from 363.4 to 1,681 mg L(-1) in A7. Unlike some patents where the highest productivity was achieved at 24 h or afterwards, in this research the best productivity of the recombinant acidic subunit was attained at 4 and 6 h of induction using both media, respectively.