En los sistemas de crianza intensiva especialmente en cerdos, la resistencia antimicrobiana de algunas bacterias patógenas, se ha convertido en un problema mundial, tanto para los productores como para los consumidores. El uso de microorganismos probióticos aislados de calostro de cerda criadas en sistemas intensivos han demostrado eficacia en la inhibición del crecimiento de algunos patógenos entéricos. Se eligieron dos cepas denominadas como BAL1 y BAL3, a las cuales se les evaluó el potencial bactericida de los extractos bacterianos sobre el patógeno Salmonella thipymurium, por el método de difusión en pozos en agar Mueller Hinton. Los extractos se obtuvieron ajustando el inóculo a 0,5 McF en caldo MRS, centrifugados a 6.000 rpm por 5 minutos y filtrados con membrana de 0,2 µm. Ambos extractos mostraron tener un alto potencial bactericida frente a esta bacteria, con promedios de halo de inhibición de 11 mm in vitro.

Food industry has grown in recent years mainly due to the supply of functional foods with probiotics and prebiotics. The viability of Lactobacillus casei and the properties of blackberry suspensions added with inulin were evaluated using a central design composed of the following factors: mass fraction of total solid blackberry concentrate (XTSBC) (0.103-0.120), [McFarland] (6-10), inulin (2.78-3.68%), and mass blackberry concentrate (BC)/mass inoculum (R) (5-20); and the dependent variables: moisture (M), pH, acidity, °Brix, total solids suspension (TSS), viscosity (μ), zeta potential (z), and Log CFU/g. Results of the experimental optimization of multiple responses were: XTSBC (0.103), [McFarland] (10), inulin (3.12%w/w), and R (18.5); being the dependent variables: M=86.7±0.0%, pH=2.74±0.01, acidity=3.1±0.0%, °Brix=11.0±0.1%, TSS=13.3±0.0%, µ=1288.0±20.1 cP, z=-13.3±0.3 mV and Log CFU/g=7.8±0.5. The probiotic microorganism Lb. casei ATCC 393 presents an adaptability in suspensions based on BC and inulin, which guarantee its viability and a possible use for obtaining an innovative spray-dried product.

Background: Lactic Acid Bacteria (LAB) are of special interest in the food industry due to their ability to produce metabolites. Among them, bacteriocins, which can inhibit the growth of altering microorganisms, and pathogens in a wide variety of foods, are considered safe for human consumption and are used as preservatives. Objectives: Evaluate the effect of a bacteriocin found by in silico methods on the microbiota present in Antioquian soft cheese. Methods: In this research, we design a synthetic bacteriocin, called Bac 22, found in the genome of Lactobacillus casei using the genomic mining methodology and bioinformatics tools. We also conducted a preliminary biological and hemolytic activities studies of the Bac 22 toward the microbiota present in the Antioquian soft cheese (Quesito Antioqueño). Results: The bacteriocin Bac 22 at a concentration of 100 μM presented a hemolytic capacity lower than 1% and reduced the CFU / g of total coliforms significantly when added to Antioquian soft cheese for eight days. Conclusions: The Bac 22 demonstrated a positive potential effect over the shelf life of a dairy product, such as the Antioquian soft cheese.

The goal of this research project was to assess the quality of sugarcane powder, during storage, that had been biofortified with kefir grains (SP+KG). The powder was obtained by spray drying (SD) sugarcane concentrate that was previously fermented with kefir grains (KG). Maltodextrin, 20% w/w, was used as a drying additive, and high viability of the microbial consortium (lactobacilli, lactococci and yeast) was always sought in order to obtain a functional food enriched with probiotic microorganisms, which facilitate storage and consumption. The product was packed, both vacuum (V) and non-vacuum (WV), and stored at 10, 20 and 30°C for 180 days. The results showed significant differences (p < 0.05) in the survival rate of lactobacilli and lactococci for the time, temperature and packaging type (PT) factors; however, the yeast showed no significant differences for the PT factor. For the survival of yeast, lactococci and lactobacilli, the best temperature was 10°C and the best packaging type was V. The survival rates reached with these conditions were 62.82% (yeast), 81.22% (lactococci) and 87.82% (lactobacilli). In addition, the levels attained in terms of physical and chemical properties defined the quality specifications of the product. The sugarcane matrix is an effective vehicle of components with physiological activity such as the microorganisms present in kefir. This qualifies the product as a potential functional food.

En este estudio se evalúa la inactivación de Bacillus licheniformis en extractos líquidos de café usando calentamiento por microondas. Para lograr medidas precisas de temperatura, se desarrolló y calibró un sensor de fibra óptica para medir en tiempo real e in situ la temperatura del extracto. Usando un diseño central compuesto, se evaluaron diferentes condiciones de tiempo de proceso, niveles de potencia y volumen de muestra; además, fue evaluado la concentración de solidos solubles del extracto de café y la posición de la muestra en la cavidad del microondas. Adicionalmente, se evalúan las propiedades fisicoquímicas y sensoriales del producto. Los resultados muestran que la mayor reducción del microorganismo ocurre con un tiempo de proceso de 19 segundos, nivel de potencia 6, volumen de muestra 11 mL y que la más alta destrucción biológica ocurre en el centro del horno.