Cristina Ramírez-Toro

Bio: Cristina Ramírez-Toro is an academic researcher from University of Valle. The author has contributed to research in topics: Gluten free & Lactic acid fermentation. The author has an hindex of 3, co-authored 8 publications receiving 62 citations.

Mechanisms of action of novel ingredients used in edible films to preserve microbial quality and oxidative stability in sausages - A review

Abstract: Background Loss of organoleptic and microbial quality of sausages is a phenomenon mostly given by lipid oxidation, enzymatic autolysis, and presence of pathogenic microorganisms in meat, as well as inappropriate handling and storage conditions. The fast shortage of meat products unleashed by these processes may cause foodborne diseases and productivity losses. Therefore, the use of natural bioactive agents has been proposed as a suitable solution to address this problem. However, the phenomena exerted by specific molecules of these compounds to prevent the depletion of sausage quality are not clear enough. Scope and approach This review encompasses an overview of oxidative and bacterial spoilage in sausages, and a description of some biochemical mechanisms of novel bioactive compounds that have been included in film formulations to delay the shortage of these meat products. Key Findings and Conclusions Edible films containing bioactive compounds have been reviewed in order to analyze ingredients that may improve organoleptic and/or microbiological quality of sausages over time, highlighting relevant features concerning their antibacterial and antioxidant properties. Some of the main mechanisms of action have been related to pore formation and permeation of bacterial membrane, as well as depletion of its proton motive force, causing down-regulation of its metabolic functions and even cell death. On the other hand, hydroxyl groups from plant extracts may help to neutralize free radicals involved in lipid oxidation.

Reduction in saponin content and production of gluten-free cream soup base using quinoa fermented with Lactobacillus plantarum

Abstract: This study explored the effect of Lactobacillus plantarum 1 on the main anti-nutritional compound (saponin) and the rheological and physicochemical properties of quinoa doughs to produce a dehydrated soup base. A full factorial design using an ANOVA and a Tukey test (p < .05) was used to evaluate the effects of two factors: concentration of the inoculum (two levels) and fermentation time (four levels). The best experimental treatment was dried in a heat pump dryer at 40 and 50 °C, at 0.8 and 1.2 m/s, and drying processes were modeled using thin-layer math equations. Then, a mixture design was used to evaluate the interactions between the dried dough, rice flour and maltodextrin to select an optimum mix according to the objective function (average value of the three commercial cream soups). A base for the quinoa soup with a permissible saponins content and viscosity similar to that of trademark products was obtained. Practical applications The results of this research will help the food industry to cook high nutritional quality soups using gluten-free ingredients. Moreover, the use of lactic acid bacteria for fermenting quinoa is a good technique for improving the organoleptic characteristics and rheological properties of the final product. In addition, the culture medium was based on quinoa flour to help decrease the costs of the process compared with the price of commercial MRS broth.

Digestibility and availability of nutrients in bee pollen applying different pretreatments

Abstract: Bee pollen is characterized by its high nutritional value that could be used in human diet, specifically for its value in protein and antioxidant capacity. Different studies emphasize that pollen shows a restriction in nutrient absorption caused by its complex external cell wall, being not easily digestible by monogastric species as bees and humans. The objective of this study was to apply different pretreatments: enzymatic, alkaline, dry thermal and wet thermal. In order to evaluate the effect of each pretreatment, protein by Bradford method, in vitro digestibility, antioxidant capacity and total phenols were quantified. Protein estimated by Bradford method decreased in pretreated pollen, due to the breakage of peptide bonds, and the digestibility raise from 62% in untreated pollen to 85-98% in pretreated pollen. In relation to antioxidant capacity, it showed a nonrepresentative decrease regarding other vegetable matrices, with the exception of a raise in phenols for some pretreatments. Such results coincide with microstructural changes observed in pretreated pollen micrographs. Finally, the variables assessed by principal component analysis showed differences for every pretreatment.

Fungal evolution: diversity, taxonomy and phylogeny of the Fungi.

Abstract: The fungal kingdom comprises a hyperdiverse clade of heterotrophic eukaryotes characterized by the presence of a chitinous cell wall, the loss of phagotrophic capabilities and cell organizations that range from completely unicellular monopolar organisms to highly complex syncitial filaments that may form macroscopic structures. Fungi emerged as a 'Third Kingdom', embracing organisms that were outside the classical dichotomy of animals versus vegetals. The taxonomy of this group has a turbulent history that is only now starting to be settled with the advent of genomics and phylogenomics. We here review the current status of the phylogeny and taxonomy of fungi, providing an overview of the main defined groups. Based on current knowledge, nine phylum-level clades can be defined: Opisthosporidia, Chytridiomycota, Neocallimastigomycota, Blastocladiomycota, Zoopagomycota, Mucoromycota, Glomeromycota, Basidiomycota and Ascomycota. For each group, we discuss their main traits and their diversity, focusing on the evolutionary relationships among the main fungal clades. We also explore the diversity and phylogeny of several groups of uncertain affinities and the main phylogenetic and taxonomical controversies and hypotheses in the field.

A review of active packaging in bakery products: Applications and future trends

Abstract: Background Rapid socio-economic development has allowed bakery products to gradually become a significant portion of people's daily diet throughout the world. However, microbial contamination and oxidation of lipids, as well as proteins in bakery products, may cause substantial economic losses and even threaten human health. The quality and safety properties of bakery products are highly dependent on packaging materials and technologies. Scope and approach The research into active packaging is a tremendous breakthrough towards solving these economic and safety problems while at the same time providing innovative methods to extend the shelf-life of bakery products. This article reviewed the factors affecting bakery products’ shelf-life and highlighted the different active packaging materials with myriad applications in bakery products, including antimicrobial, antioxidant, ethanol emitters and moisture absorbers packaging. Furthermore, consumer preferences towards active packaging, as well as the challenges and future trends in the development of active packaging in the bakery industry were also discussed. Key findings and conclusions By absorbing or releasing active compounds, active packaging systems can effectively delay or prevent microbial spoilage, reduce oxidation, and enhance the safety and quality of bakery products. Some innovative materials, such as stimuli-responsive antimicrobial materials, should be considered to successfully implement active packaging solutions in the bakery industry.

The sourdough fermentation is the powerful process to exploit the potential of legumes, pseudo-cereals and milling by-products in baking industry.

Abstract: In the era of fighting wastes and paying close attention to sustainability and new protein sources, legumes, pseudo-cereals and milling by-products deserve all the efforts for increasing their cons...

Fortification of edible films with bioactive agents: a review of their formation, properties, and application in food preservation.

Abstract: Biodegradable films constructed from food ingredients are being developed for food coating and packaging applications to create more sustainable and environmentally friendly alternatives to plastic...

Fermentative Foods: Microbiology, Biochemistry, Potential Human Health Benefits and Public Health Issues.

Abstract: Fermented foods identify cultures and civilizations. History, climate and the particulars of local production of raw materials have urged humanity to exploit various pathways of fermentation to produce a wide variety of traditional edible products which represent adaptations to specific conditions. Nowadays, industrial-scale production has flooded the markets with ferments. According to recent estimates, the current size of the global market of fermented foods is in the vicinity of USD 30 billion, with increasing trends. Modern challenges include tailor-made fermented foods for people with special dietary needs, such as patients suffering from Crohn’s disease or other ailments. Another major challenge concerns the safety of artisan fermented products, an issue that could be tackled with the aid of molecular biology and concerns not only the presence of pathogens but also the foodborne microbial resistance. The basis of all these is, of course, the microbiome, an aggregation of different species of bacteria and yeasts that thrives on the carbohydrates of the raw materials. In this review, the microbiology of fermented foods is discussed with a special reference to groups of products and to specific products indicative of the diversity that a fermentation process can take. Their impact is also discussed with emphasis on health and oral health status. From Hippocrates until modern approaches to disease therapy, diet was thought to be of the most important factors for health stability of the human natural microbiome. After all, to quote Pasteur, “Gentlemen, the microbes will have the last word for human health.” In that sense, it is the microbiomes of fermented foods that will acquire a leading role in future nutrition and therapeutics.