Camel Milk: Antimicrobial Agents, Fermented Products, and Shelf Life

The camel milk (CM) industry has witnessed a notable expansion in recent years. This expansion is primarily driven by the rising demand for CM and its fermented products. The perceived health and nutritional benefits of these products are mainly responsible for their increasing popularity. The composition of CM can vary significantly due to various factors, including the breed of the camel, its age, the stage of lactation, region, and season. CM contains several beneficial substances, including antimicrobial agents, such as lactoferrin, lysozyme, immunoglobulin G, lactoperoxidase, and N-acetyl-D-glucosaminidase, which protect it from contamination by spoilage and pathogenic bacteria, and contribute to its longer shelf life compared to bovine milk (BM). Nevertheless, certain harmful bacteria, such as Listeria monocytogenes, Yersinia enterocolitica, and Escherichia coli, have been detected in CM, which is a significant public health concern. Therefore, it is crucial to understand and monitor the microbial profile of CM and follow good manufacturing practices to guarantee its safety and quality. This review article explores various aspects of CM, including the types of beneficial and harmful bacteria present in it, the composition of the milk, its antimicrobial properties, its shelf life, and the production of fermented CM products.

The Effect of the Supplementation of Humic Substances and Fermented Products in the Feed on the Content of Salinomycin Residues in Poultry Tissues

The presence of antimicrobial residues in products of animal origin is a constant problem for consumer health. The aim of this study was to observe the effect of the addition of humic substances (H), fermented products (F) and a mixture of both (FH) to feed supplemented with the coccidiostat salinomycin, compared with a control group (C), on the content of salinomycin residues in the edible tissues of broiler chickens using two microbial inhibition screening methods, Explorer 2.0 test and the Screening Test for Antibiotic Residues (STAR), and a confirmatory competitive enzyme immunoassay analysis (Salinomycin ELISA Kit). The results of the microbial inhibition tests showed a gradual decline in the positive results in the tissue samples from the last day of salinomycin administration (30th day) tothe last day of fattening (37th day, day of slaughter) in group C and no positive results in the tissue samples from experimental groups H, F and FH slaughtered on the last day of fattening. Using the Salinomycin ELISA Kit, salinomycin was detected in the chicken muscle tissues of all the control and experimental groups. However, no sample from any group contained salinomycin at a concentration exceeding the maximum residue limits set by European law. The high level of significance (p < 0.001) confirmed the positive influence of the administration of humic substances and fermented products on the content of salinomycin residues in chicken tissues.

Properties of Yoghurt Fortified in Lactoferrin with Effect of Storage Time

The stability of fortified yoghurts during refrigerated storage is important for industry and the consumer. The aim of the study was to evaluate the nutritional value, microbiological quality, organoleptic properties, and structure of natural yoghurts made with the addition of lactoferrin during refrigerated storage. In this study, we produced natural yoghurts fortified in lactoferrin, using YC-X11 yoghurt starter culture based on Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. Physicochemical (acidity, nutritional value and structure) as well as microbiological and organoleptic changes occurring during 28-days refrigerated storage were determined. Storage research made it possible to determine the direction of changes taking place in the products. The analysed parameters did not differ statistically significantly between the control yoghurts and those with the addition of lactoferrin. Textural and rheological studies also shown that the addition of lactoferrin did not significantly change the structure of the yoghurt. The yoghurts were characterized by high sanitary and hygienic quality during the whole refrigerated storage. Lactoferrin has a positive effect on the durability of the product.

Current trends and future perspective of probiotic yeasts research in Indonesia

Indonesia is a mega biodiversity country with various local wisdom, including the enormous variety of fermented foods and beverages. Indonesian researchers have conducted an intensive study to understand the diversity of microbes on those fermented products, one of which shows probiotic properties. Compared to that lactic acid bacteria, the study on probiotic yeasts is less explored. Probiotic yeast isolates are commonly isolated from traditional Indonesian fermented products. Saccharomyces, Pichia, and Candida are among Indonesia's most popular genera of probiotic yeasts, primarily applied in poultry and human health. The exploration of functional probiotic characteristics, such as antimicrobial, antifungal, antioxidant, and immunomodulator, has been widely reported from these local probiotic yeast strains. In vivo studies in a model organism such as mice conclude the prospective functional probiotic characteristics of the yeast isolates. Employment of current technology, such as omics, is essential in elucidating those functional properties. Advanced research and development of probiotic yeasts in Indonesia are gaining significant attention currently. For instance, probiotic yeasts-mediated fermentation in the production of kefir and kombucha are among the trend with promising economic value. The future trends of probiotic yeasts research in Indonesia are discussed in this review to give valuable sight into the application of indigenous probiotic yeasts in various fields.

Bacterial extracellular vesicles and associated functional proteins in fermented dairy products with Lacticaseibacillus paracasei

Cells of all kingdoms produce extracellular vesicles (EVs); hence, they are present in most environments and body fluids. Lacticaseibacillus paracasei produces EVs that have attached biologically active proteins (P40 and P75). In this study, EV and functional proteins were found in five different commercial dairy-fermented products carrying L. paracasei. Strains present in those products were isolated, and with one exception, all produced small EVs (24-47 d.nm) carrying P40 and P75. In order to winnow bacterial EV from milk EV, products were subjected to centrifugal fractionation at 15,000 × g (15 K), 33,000 × g (33 K), and 100,000 × g (100 K). P75 was present in all supernatants and pellets, but P40 was only found in two products bound to the 15 and 33 K pellets, and 16S rDNA of L. paracasei could be amplified from all 100 K EVs, indicating the presence of L. paracasei EV. To investigate the interactions of bacterial EV and proteins with milk EV, L. paracasei BL23 EV was added to three commercial UHT milk products. Small-size vesicles (50-60 d.nm) similar to L. paracasei BL23 EV were found in samples from 100 K centrifugations, but intriguingly, P40 and P75 were bound to EV in 15 and 33 K pellets, containing bovine milk EV of larger size (200-300 d.nm). Sequencing 16S rDNA bands amplified from EV evidenced the presence of bacterial EVs of diverse origins in milk and fermented products. Furthermore, L. paracasei 16S rDNA could be amplified with species-specific primers from all samples, showing the presence of L. paracasei EV in all EV fractions (15, 33, and 100 K), suggesting that these bacterial EVs possibly aggregate and are co-isolated with EV from milk. P40 and P75 proteins would be interacting with specific populations of milk EV (15 and 33 K) because they were detected bound to them in fermented products and milk, and this possibly forced the sedimentation of part of L. paracasei EV at lower centrifugal forces. This study has solved technically complex problems and essential questions which will facilitate new research focusing on the molecular behavior of probiotics during fermentation and the mechanisms of action mediating the health benefits of fermented products.

Nutritional and ethnomedicinal scenario of koumiss: A concurrent review

Fermented foods are an essential source of nutrition for the communities living in developing areas of the world. Additionally, traditional fermented products are a rich source of various bioactive components. Experimental research regarding the functional exploration of these products is a way forward for better human health. Among fermented foods, Koumiss is rich in vitamins especially vitamin C and minerals, i.e., phosphorus and calcium. In addition, it is also rich in vitamins A, E, B2, B12, and pantothenic acid. High concentrations of lactose in milk favor bacterial fermentation, as the original cultures decompose it into lactic acid. Koumiss contains essential fatty acids such as linoleic and linolenic acid. Koumiss offers many health benefits including boosting the immune system and maintains blood pressure, good effect on the kidneys, endocrine glands, gut system, liver, and nervous and vascular system. The rich microflora from the fermented product has a pivotal role in maintaining gut health and treating various digestive diseases. The core focus of the current review paper is to highlight the nutritional and therapeutic potential, i.e., anticarcinogenic, hypocholesterolemia effect, antioxidative properties, antibacterial properties, antibacterial spectrum, intestinal enlargement, and β-galactosidase activity, of Koumiss as a traditional fermented product. Moreover, history and production technology of the Koumiss are also the main part of this review paper.

Submerged fermentation of Ginkgo biloba seed powder using Eurotium cristatum for the development of ginkgo seeds fermented products

BACKGROUND

Ginkgo biloba seeds are well known for the significant curative effects on relieving cough and asthma. However, the development of products from ginkgo seeds still falls behind at present, resulting in a great waste of ginkgo seeds' resource. In this work, submerged fermentation of ginkgo seed powder using Eurotium cristatum was studied to investigate its feasibility as a new processing method.

RESULTS

To promote the growth of E. cristatum, the optimum fermentation medium was 80.0 g L^-1 of ginkgo seed powder with addition of 5.0 g L^-1 calcium chloride (CaCl₂ ), 4.0 g L^-1 magnesium sulfate (MgSO₄ ), 1.25 g L^-1 zinc sulfate (ZnSO₄ ) and 0.65 g L^-1 iron(II) sulfate (FeSO₄ ). The optimum fermentation conditions were pH 5.8 ± 0.1, inoculum size 5.1 × 10⁶  CFU mL^-1 , liquid medium volume 100 mL in 250-mL Erlenmeyer flask and fermentation 4 days. Through fermentation, the production of lovastatin in fermentation broth could reach up to 32.97 ± 0.17 μg mL^-1 and the total antioxidant capacity was improved by more than two-fold. In addition, 40.15% of the ginkgotoxin in ginkgo seed powder was degraded while the entire degradation of ginkgolic acids was obtained. Moreover, fermented ginkgo seed powder suspension presented pleasant fragrances, and the activities of amylase and protease were enhanced to 11.30 ± 0.10 U mL^-1 and 23.01 ± 0.20 U mL^-1 , respectively.

CONCLUSIONS

Submerged fermentation using E. cristatum could significantly enhance the functional value and safety of ginkgo seed powder, and had great potential to become a novel processing method for the development of ginkgo seeds fermented products. © 2020 Society of Chemical Industry.

Bacillus licheniformis-Fermented Products Improve Growth Performance and Intestinal Gut Morphology in Broilers under Clostridium perfringens Challenge

Necrotic enteritis caused by Clostridium perfringens has reemerged as a severe poultry disease worldwide since the ban on the routine use of antibiotics in animal feed. Probiotics are considered alternatives to antibiotic growth promoters. Bacillus species are the most common microorganisms used as probiotics in the feed industry. The current study investigated the growth and surfactin levels of Bacillus licheniformis in solid-state fermentation using different substrates and evaluated the effects of B. licheniformis-fermented products on growth performance and intestinal morphology in broilers exposed to C. perfringens. The highest viable biomass and surfactin concentration of B. licheniformis-fermented products was observed at 2% molasses and 20% soybean meal supplementation during fermentation (P<0.05). B. licheniformis-fermented product-derived surfactin inhibited the growth of C. perfringens in vitro in a dose dependent manner (P<0.05). B. licheniformis-fermented product supplementation (2 g/kg) significantly improved the body weight and average daily gain weight of broilers challenged with C. perfringens (P<0.05). B. licheniformis-fermented products significantly alleviated necrotic lesions and ameliorated intestinal morphology in broilers exposed to C. perfringens (P<0.05). Collectively, these observations demonstrate that B. licheniformis-fermented products improve growth performance and gut morphology in broilers under C. perfringens challenge. B. licheniformis-fermented products may have the potential to be used as alternatives to antibiotic growth promoters for preventive treatments against C. perfringens in broilers.

Function-Driven Design of Lactic Acid Bacteria Co-cultures to Produce New Fermented Food Associating Milk and Lupin

Designing bacterial co-cultures adapted to ferment mixes of vegetal and animal resources for food diversification and sustainability is becoming a challenge. Among bacteria used in food fermentation, lactic acid bacteria (LAB) are good candidates, as they are used as starter or adjunct in numerous fermented foods, where they allow preservation, enhanced digestibility, and improved flavor. We developed here a strategy to design LAB co-cultures able to ferment a new food made of bovine milk and lupin flour, consisting in: (i) in silico preselection of LAB species for targeted carbohydrate degradation; (ii) in vitro screening of 97 strains of the selected species for their ability to ferment carbohydrates and hydrolyze proteins from milk and lupin and clustering strains that displayed similar phenotypes; and (iii) assembling strains randomly sampled from clusters that showed complementary phenotypes. The designed co-cultures successfully expressed the targeted traits i.e., hydrolyzed proteins and degraded raffinose family oligosaccharides of lupin and lactose of milk in a large range of concentrations. They also reduced an off-flavor-generating volatile, hexanal, and produced various desirable flavor compounds. Most of the strains in co-cultures achieved higher cell counts than in monoculture, suggesting positive interactions. This work opens new avenues for the development of innovative fermented food products based on functionally complementary strains in the world-wide context of diet diversification.

African Sorghum-Based Fermented Foods: Past, Current and Future Prospects

Sorghum (Sorghum bicolor) is a well-known drought and climate resistant crop with vast food use for the inhabitants of Africa and other developing countries. The importance of this crop is well reflected in its embedded benefits and use as a staple food, with fermentation playing a significant role in transforming this crop into an edible form. Although the majority of these fermented food products evolve from ethnic groups and rural communities, industrialization and the application of improved food processing techniques have led to the commercial success and viability of derived products. While some of these sorghum-based fermented food products still continue to bask in this success, much more still needs to be done to further explore evolving techniques, technologies and processes. The addition of other affordable nutrient sources in sorghum-based fermented foods is equally important, as this will effectively augment the intake of a nutritionally balanced product.

Application of data science in risk assessment and early warning

The food supply chain has been recognised by the EU as a critical infrastructure, and its complexity is the main cause of vulnerability. Depending on the food matrix, natural and/or deliberate contamination, food-borne diseases or even food fraud incidents may occur worldwide. Consequently, robust predictive models and/or software tools are needed to support decision-making and mitigating risks in an efficient and timely manner. In this frame, the fellow participated in data collection and analysis tasks, so as to provide additional predictive models. The working programme, covered a wide range of aspects related to risk assessment including identification of emerging risks (quantitative), microbiological risk assessment, authenticity assessment, spatio-temporal epidemiological modelling and database formation for hosting predictive microbial models. The training and close integration, in the open-source, in-house (German Federal Institute for Risk Assessment (BfR)) developed software tools under the framework of FoodRisk-Labs (https://foodrisklabs.bfr.bund.de.) for data analysis, predictive microbiology, quantitative microbiological risk assessment and automatic data retrieval purposes allowed for the independent use. Moreover, the fellow actively contributed to the update of the upcoming Yersinia enterocolitica risk assessment, and also in authenticity assessment of edible oils. Over the course of the year, the fellow was closely involved in international and national research projects with experts in the above-mentioned disciplines. Lastly, he consolidated his acquired knowledge by presenting his scientific work to conferences, and BfR-internal meetings.

Glyceryl 1,3-Dipalmitate Produced from Lactobacillus paracasei subspecies. paracasei NTU 101 Inhibits Oxygen-Glucose Deprivation and Reperfusion-Induced Oxidative Stress via Upregulation of Peroxisome Proliferator-Activated Receptor γ in Neuronal SH-SY5Y Cells

Glyceryl 1,3-dipalmitate (GD) purified from Lactobacillus paracasei subsp. paracasei NTU 101-fermented products has been demonstrated to possess neuroprotective properties. We determined the effect of GD on oxygen-glucose deprivation and reperfusion (OGD/R)-induced SH-SY5Y neuroblastoma cell death. GD ameliorated OGD/R-induced apoptosis by elevating the protein expression of nuclear peroxisome proliferator-activated receptor γ (PPARγ) and nuclear factor erythroid 2-related factor 2 (Nrf2), thereby attenuating reactive oxygen species (ROS) generation. Pretreatment with GD reduced nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) expression from 1.54 ± 0.27 to 0.84 ± 0.46, thereby attenuating the induction of pro-inflammatory mediators, and increased the plasma membrane Ca²⁺ ATPase (PMCA) levels from 0.81 ± 0.02 to 1.08 ± 0.06, thus reducing the levels of cytosolic Ca²⁺; this also correlated with reduced cell death. We conclude that GD prevents SH-SY5Y cells from injury after OGD/R insult, possibly by modulating oxidative stress and inflammatory response.

The history of probiotics: the untold story

Probiotic, a word derived from Latin, means 'for life'. A long time before the awareness of probiotic microorganisms, fermented products, such as beer, bread, wine, kefir, kumis and cheese had been very frequently used for nutritional and therapeutic purposes. It is widely believed that fermented products were probably found, or better to say, discovered spontaneously. The legend tells that yoghurt is most likely resulted from a fermentation process within the animal skin bags used for transportation of water and milk in regions with low humidity and high temperatures (Middle Asia and Middle East). The history of probiotics goes paralel with the evolution of human race and, thanks to the sophisticated techniques at the moment, can be traced back to the ancient times, nearly 10,000 years ago. The aims of this review are to highlight the important events for probiotic history, to correct the widely available anonymous misinformation in the literature and to remind to the readers important characters in its history.