Comparative analysis of spray‐drying microencapsulation of Bifidobacterium adolescentis and Lactobacillus acidophilus cultivated in different growth media

Advances in oligosaccharides and polysaccharides with different structures as wall materials for probiotics delivery: A review

Probiotics are active microorganisms that are beneficial to the health of the host. However, probiotics are highly sensitive to the external environment, and are susceptible to a variety of factors that reduce their activity during production, storage, and use. Microencapsulation is an effective method that enhances probiotic activity. Macromolecules like polysaccharides, who classified as biologically active prebiotics, have attracted significant attention for their utility in probiotic microencapsulation. This article summarized the types of commonly used microencapsulation materials and their structural characteristics from the perspective of polysaccharides prebiotics. It also discussed recent advancements, probiotic-prebiotic microcapsule-based modulation of the immune system, as well as the associated limitations. Furthermore, the advantages and disadvantages of eight prebiotics as microencapsulation wall materials. The honeycomb structure of β-glucan enhances the bioavailability of probiotics, while, fructooligosaccharide and galactooligosaccharides improve microbead structure to tightly encapsulate probiotics. The terminal reducing groups of isomaltooligosaccharides and the free hydroxyl groups in xylooligosaccharides also positively affect the structure of microcapsules. Prebiotics not only enhance the survival rate and biological activity of probiotics as embedding materials during storage, but also exert their own probiotic effects. Collectively, prebiotics holds great promise as microencapsulation materials for probiotics delivery.

Screening the Protective Agents Able to Improve the Survival of Lactic Acid Bacteria Strains Subjected to Spray Drying Using Several Key Enzymes Responsible for Carbohydrate Utilization

The aim of this study was to identify the most effective protectants for enhancing the viability of specific lactic acid bacteria (LAB) strains (Lactobacillus delbrueckii subsp. bulgaricus CICC 6097, Lactiplantibacillus plantarum CICC 21839, Lactobacillus acidophilus NCFM) by assessing their enzymatic activity when exposed to spray drying (inlet/outlet temperature: 135 °C/90 °C). Firstly, it was found that the live cell counts of the selected LAB cells from the 10% (w/v) recovered skim milk (RSM) group remained above 107 CFU/g after spray drying. Among all the three groups (1% w/v RSM group, 10% w/v RSM group, and control group), the two enzymes pyruvate kinase (PK) and lactate dehydrogenase (LDH) were more sensitive to spray drying than hexokinase (HK) and β-galactosidase (β-GAL). Next, transcriptome data of Lb. acidophilus NCFM showed that 10% (w/v) RSM improved the down-regulated expressions of genes encoding PK (pyk) and LDH (ldh) after spray drying compared to 1% (w/v) RSM. Finally, four composite protectants were created, each consisting of 10% (w/v) RSM plus a different additive-sodium glutamate (CP-A group), sucrose (CP-B group), trehalose (CP-C group), or a combination of sodium glutamate, sucrose, and trehalose (CP-D group)-to encapsulate Lb. acidophilus NCFM. It was observed that the viable counts of strain NCFM (8.56 log CFU/g) and enzymatic activity of PK and LDH in the CP-D group were best preserved compared to the other three groups. Therefore, our study suggested that measuring the LDH and PK activity could be used as a promising tool to screen the effective spray-dried protective agent for LAB cells.

Trends in Sieving and Its Applications in Cereals. A Literature Review

In the agroindustry, sieving is a unit operation of great value, this work aims to make a literature review on sieving in cereals, a search equation was carried out in the Scopus database with the keywords sieve, screen, food process, and cereal that resulted in 132 articles and 174 patents. Of the articles, 44 were directly related to sieving and 14 more had something to do with sieving; of the patents, in the last 10 years only 7 were directly related to sieving. To find new trends, raw materials, patent analysis, and information analysis, tables were built with name, year, author, keywords, countries, quartile, journal, relationship with the agroindustry, and purpose. Among the most important conclusions was the application of sieving in raw materials such as Rice, Corn, Wheat, Cotton, Millet, Quinoa, Almonds, Barley, Potato, Yucca, Microorganisms, Oats, Cotton, Protein, Peppers, and Chia Seed. Furthermore, the use of rotating and vibrating sieves was identified, and also their positive effects on the physicochemical, standardization, and classification of raw materials were identified. The different types of equipment or methods focused on sieving, that has been granted use or design patent, were also recognized.

Optimization of the Effects of Different Temperatures and Compositions of Filmogenic Solution on Lactobacillus Salivarius Using Predictive Mathematical Models

It is well known that intake of probiotic brings health benefits. Lactic bacteria with probiotic potential have aroused the interest of the industry in developing food products that incorporate such benefits. However, incorporating probiotic bacteria into food is a challenge for the industry, given the sensitivity of probiotic cultures to process conditions. Therefore, the objective of this study is to evaluate gelatin- and inulin-based filmogenic solutions as a potential vehicle for incorporating probiotics into food products and to model the fermentation kinetics. L. salivarius (Lactobacillus salivarius) growth in filmogenic solutions was analyzed under the influence of a variety gelatin concentrations (1.0–3.0%) and inulin concentrations (4.0–6.0%) and fermented under the effect of different temperatures (25–45 °C). A full 2³ factorial plan with three replicates at the central point was used to optimize the process. The impacts of process conditions on cell development are fundamental to optimize the process and make it applicable by the industry. The present study showed that the optimal conditions for the development of probiotic cells in filmogenic solutions are a combination of 1.0% gelatin with 4.0% inulin and fermentation temperature of 45 °C. It was observed that the maximum cell growth occurred in an estimated time of about 4 h of fermentation. L. salivarius cell production and substrate consumption during the fermentation of the filmogenic solution were well simulated by a model proposed in this article, with coefficients of determination of 0.981 (cell growth) and 0.991 (substrate consumption).

Spray drying and storage of probiotic-enriched almond milk: probiotic survival and physicochemical properties

BACKGROUND

The combination of the nutritional profile of almond milk with the benefits of probiotic bacteria is an interesting development to meet the demand for sustainable and health-promoting food. Almond milk inoculated with probiotic Lactobacillus plantarum (ATCC8014) was spray dried and the almond, its milk, and powders were characterized physicochemically. Samples were characterized in terms of bacterial survival before and after atomization. Bacterial viability and total fatty acid changes were studied during 8 months' storage at 4 and 22 °C.

RESULTS

Results showed adequate physicochemical properties and an optimal bacterial survival rate, maintaining almost the same values before and after the spray-drying operation. A decrease was observed in the cell viability for samples stored at 4 °C. However, the cell count was maintained above the minimum level suggested (10⁷ living cells) to allow potential probiotic functionality for 8 months. On the other hand, the count cell of powders stored at 22 °C was below the minimum level required after 6 months. The fatty acids profile was not significantly (P > 0.05) affected by storage time and temperature.

CONCLUSION

A new almond-based-product with probiotics was developed to meet consumer demands. Almond nutrients were recovered from almond milk powder and were found to be a good source of K and high in Mg and in monounsaturated fat. The viability of bacteria was assured during 8 months of storage at 4 °C and up to 6 months for samples stored at 22 °C. © 2020 Society of Chemical Industry.

Stabilizing lactate production through repeated batch fermentation of food waste and waste activated sludge

Bio-valorization of organic waste streams, such as food waste and waste activated sludge, to lactic acid (LA) has recently drawn much attention. It offers an opportunity for resource recovery, alleviates environmental issues and potentially turns a profit. In this study, both stable and high LA yield (0.72 ± 0.15 g/g total chemical oxygen demand) and productivity rate (0.53 g/L•h) were obtained through repeated batch fermentation. Moreover, stable solubilization and increase in the critical hydrolase activities were achieved. Depletions of ammonia and phosphorus were correlated with the LA production. The relative abundance of the key LA bacteria genera (i.e., Alkaliphilus, Dysgonomonas, Enterococcus and Bifidobacterium) stabilized in the repeated batch reactor at a higher level (44.5 ± 2.53%) in comparison with the batch reactor (26.2 ± 4.74%). This work show a practical way for the sustainable valorization of organic wastes to LA by applying the repeated batch mode during biological treatment.