Fermented Food Products Research Articles

Cell-surface protein YwfG of Lactococcus lactis binds to α-1,2-linked mannose.

Lactococcus lactis strains are used as starter cultures in the production of fermented dairy and vegetable foods, but the species also occurs in other niches such as plant material. Lactococcus lactis subsp. lactis G50 (G50) is a plant-derived strain and potential candidate probiotics. Western blotting of cell-wall proteins using antibodies generated against whole G50 cells detected a 120-kDa protein. MALDI-TOF MS analysis identified it as YwfG, a Leu-Pro-any-Thr-Gly cell-wall-anchor-domain-containing protein. Based on a predicted domain structure, a recombinant YwfG variant covering the N-terminal half (aa 28-511) of YwfG (YwfG28-511) was crystallized and the crystal structure was determined. The structure consisted of an L-type lectin domain, a mucin-binding protein domain, and a mucus-binding protein repeat. Recombinant YwfG variants containing combinations of these domains (YwfG28-270, YwfG28-336, YwfG28-511, MubR4) were prepared and their interactions with monosaccharides were examined by isothermal titration calorimetry; the only interaction observed was between YwfG28-270, which contained the L-type lectin domain, and d-mannose. Among four mannobioses, α-1,2-mannobiose had the highest affinity for YwfG28-270 (dissociation constant = 34 μM). YwfG28-270 also interacted with yeast mannoproteins and yeast mannan. Soaking of the crystals of YwfG28-511 with mannose or α-1,2-mannobiose revealed that both sugars bound to the L-type lectin domain in a similar manner, although the presence of the mucin-binding protein domain and the mucus-binding protein repeat within the recombinant protein inhibited the interaction between the L-type lectin domain and mannose residues. Three of the YwfG variants (except MubR4) induced aggregation of yeast cells. Strain G50 also induced aggregation of yeast cells, which was abolished by deletion of ywfG from G50, suggesting that surface YwfG contributes to the interaction with yeast cells. These findings provide new structural and functional insights into the interaction between L. lactis and its ecological niche via binding of the cell-surface protein YwfG with mannose.

Complete genome sequence of Limosilactobacillus fermentum JNU532 as a probiotic candidate for the functional food and feed supplements

Lactic acid bacteria (LAB) have been reported to possess various beneficial properties and are commonly used as probiotics. LAB play a crucial role in milk fermentation, industrial lactic acid fermentation, and health and medicine. Limosilactobacillus fermentum isolated from fermented dairy and food products is considered as 'Generally Recognized as Safe' by FDA. Limosilactobacillus fermentum plays an important role in modulation of the intestinal microbiota, enhancing the host immune system and improving feed digestibility. We isolated a probiotic candidate that was identified and named Limosilactobacillus fermentum JNU532. In a previous report, cell-free culture of L. fermentum JNU532 exhibited anti-melanogenic and antioxidant activities. In this study, we present the complete genome assembly of the bacterial strain JNU532. The final genome consists of one circular chromosome (2,077,416 base pairs) with a guanine + cytosine (GC) ratio of 51.5%.

Cytokine-mediated immunoregulatory activity of Lactobacillus species in a carrageenan-induced acute inflammatory model.

Using paw edema acute inflammatory model induced by carrageenan (1%) in Wistar rats, the immunoregulatory action of Lactobacillus sp., isolated from two locally fermented food products in Nigeria: Nunu (a yogurt-like milk product) and Ogi (guinea corn slurry), was investigated. The rats were distributed into seven groups (A-G). Rats in group A did not receive any therapy or carrageenan inflammation, whereas those in group B received a carrageenan injection only. Groups C-F were orally administered with lactic acid bacteria (LAB) strains (5 × 107 CFU/ml), whereas group G received diclofenac sodium (150 mg/kg body weight) following the administration of carrageenan. At regular intervals, paw thickness (mm) was measured. Microscopy was used to count the number of leukocytes; myeloperoxidase (MPO) activity was used to measure the neutrophil accumulation in the paw tissue; and rat serum samples were subjected to ELISA to identify cytokine assays for C-reactive protein (CR-P), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β). All of the LAB-treated groups showed a statistically significant decrease in paw thickness, and their neutrophil and monocyte infiltration was significantly affected. Compared with the control groups, oral administration with LAB significantly suppressed the MPO activity. Lactobacillus fermentum NBRC showed the most significant upregulation of serum levels of IL-10 and TGF-β though serum levels of CR-P were downregulated. Lactobacillus pentosus increased the production of TGF-β, with no significant effect on the production of IL-10. This study presents the role of Lactobacillus sp. in regulating inflammation by modifying the production of anti-inflammatory cytokines IL-10 and TGF-β.

Identification and Characterisation of Salmonella spp. Isolated from Stool Samples of a Food Poisoning Outbreak in Chite, Mizoram, India due to Consumption of Bekang-Um (Fermented Soybean)

Introduction: Traditional fermented soybean (“bekang-um”) is widely consumed by the indigenous Mizo tribe in Mizoram and plays a significant part of the local staple food. They are commonly prepared with herbs like culantro and often with just locally dried chilli flakes, implying it is mostly consumed raw without further cooking. Though it plays a staple part of the diet because of its unique taste, awareness on proper and regulated hygienic conditions during its preparation and fermentation processes is quite negligent. The fermentation process often warrants for the growth of not only commensal lactic acid fermenter bacteria like Acinetobacter spp., Lactobacillus spp., but also provides ample growth conditions for harmful bacteria like Salmonella spp., Clostridium spp., Intestinal Pathogenic E.Coli (IPEC) and Bacillus cereus. Aim: Phenotypic and molecular characterisation of Salmonella spp. isolated from the fermented food product bekang-um. Materials and Methods: The cross-sectional study was conducted within three months (October to December, 2020) in Multidisciplinary Research Unit (MRU), Zoram Medical College in collaboration with the Department of Veterinary Microbiology, CVSc and AH, Central Agricultural University, Selesih, Mizoram. A total of 18 stool samples were collected from patients (living in Chite, a small locality in Aizawl) who were still exhibiting symptoms of food poisoning (diarrhoea, vomiting and nausea) after consumption of fermented soybean all bought from their local neighbourhood fermenter and seller of the food item. The data was tabulated and statistically analysed using Microsoft Excel and sensitivity/resistance patterns were expressed in percentages. Results: Salmonella spp. was isolated from 17 out of 18 stool samples collected. Out of 17 samples, 15 exhibited Multi-Drug Resistance (MDR) phenotypically to clinically relevant and widely used antibiotics like cefotaxime, ceftriaxone, ciprofloxacin, amoxicillin-clavulanic acid. Alarmingly, resistance genes like blaCTX-M1 (70.6%), blaCTX-M2 (35.3%), blaSHV (70.6%), blaTEM (52.9%), blaNDM (5.8%), blaAmpC (100%), blaKPC (29.4%), blaVIM (23.5%), blaIMP (11.8%) were commonly detected. Moreover, Salmonella virulence determinants like invA (41.2%), stn (41.2%), and biofilm-associated virulence genes like csgA (11.8%), csgD (70.6%) and adrA (5.9%) were also identified. Conclusion: The identification and characterisation of Salmonella spp. isolated from a widely consumed food product “bekangum” (fermented soybean) with co-occurring crucial virulence, biofilm-producing and resistance gene determinants is quite alarming. The findings suggest the urgent need of implementing food safety conditions and proper preparation standards of the exotic food item, and the seriousness of the potential threat it can cause in cases of unhygienic fermentation processes.

Isolation and Characterization of Lactobacillus crispatus, Lactococcus lactis, and Carnobacterium divergens as Potential Probiotic Bacteria from Fermented Black and Green Olives (Olea europaea): An Exploratory Study.

Table olives are becoming well recognized as a source of probiotic bacteria that might be used to create a health-promoting fermented food product by traditional procedures based on the activities of indigenous microbial consortia present in local environments. Methodology. In the present study, the characterization of probiotic bacteria isolated from mince, chunks, and brine of fermented green and black olives (Olea europaea) was done based on morphological, biochemical, and physiological characteristics. Bacterial isolates demonstrated excellent survival abilities at 25, 37, and 45°C and at a variable range of pH. However, the optimum temperature is 37 and the optimum pH is 7 for all three isolates. An antimicrobial susceptibility pattern was found among these isolates through the disc diffusion method. Most of the isolates were susceptible to streptomycin, imipenem, and chloramphenicol, whereas, amoxicillin showed resistance to these isolates, and variable results were recorded for the rest of the antibiotics tested. The growth of the isolates was optimum with the supplementation of 3% NaCl and 0.3% bile salt. The isolated bacteria were able to ferment skimmed milk into yogurt, hence making it capable of producing organic acid. Isolates of Lactobacillus crispatus MB417, Lactococcus lactis MB418 from black olives, and Carnobacterium divergens MB421 from green olives were characterized as potential candidates for use as starter cultures to induce fermentation of other probiotic food products.

Nutritional and therapeutic potentials of wholesome plant-based fermented food products of India

Fermentation is an age-old technology that has been practiced since time immemorial. Application of fermentation techniques have a drastic impact on the production of numerous food items. There are a variety of traditional plant-based fermented foods and beverages developed through the process of fermentation in India. Plant-based fermented food products have many nutritional and functional properties such as high fiber, protein, phytochemicals, phytonutrients, antioxidant content, vitamins, and minerals which exhibit many health benefits and help in the prevention of certain diseases. In India a variety of plant-based fermented foods and beverages are found due to different geographical indications, cultural diversity, and variance of the raw material availability. The rural population of India prepares these products at home and markets them locally, which serves as a source of income for them. The traditional fermentation process in India promotes nutritional and therapeutic properties of the food thereafter making them shelf-stable. This study summarizes some of the most popular plant-based fermented products developed in India using traditional methods and are believed to have a beneficial impact on health. Intricate study of nutritional and therapeutic properties of these food products can be essential in providing salubrious knowledge which will provide valuable guidance for the use and development of new products on a wider scale.

Phylogenomic analysis in Latilactobacillus sakei by using polymorphisms detected by next-generation sequencing.

Latilactobacillus sakei is a lactic acid bacterium used to produce a wide range of fermented food products. To understand their characteristics and adaptability to various nutrient sources, we applied strain-specific, nucleotide-concatenated (SSC) sequences to the phylogenetic analysis of 32 L. sakei strains isolated from various locations and products. SSC sequences were developed by concatenating the polymorphisms detected by whole-genome sequencing. This enabled us to use sufficient polymorphisms and avoid the bias caused by selecting partial sequences, such as that in core genome and multi-locus sequence typing. SSC sequence-based analysis revealed that the phylogenetic relations for L. sakei are based on the different nutrition sources rather than geographical distance.

Penerapan Project Based Learning dalam Praktikum Teknologi Fermentasi di Sekolah Vokasi Institut Pertanian Bogor

Fermentation technology is one of the subjects in the Food Quality Assurance Supervisor Study Program (SJMP), Vocational School, Bogor Agricultural University (IPB) which is given to semester IV students. Prior to the 2021/2022 academic year, practicum activities were carried out using the teacher centered method using practicum instructions in the form of modules prepared by lecturers, students only followed the modules and were not involved in practicum planning and designing experiments. Through this method, students are not given the opportunity to learn to think critically, creatively, and innovate. One way to optimize the achievement of learning outcomes is to apply the Project Based Learning (PjBL) model. The research was carried out using a one-shot case study method and a descriptive approach to 111 students of the Food Quality Assurance Supervisor Study Program in semester IV. The application of Project Based Learning in the fermentation technology course produces innovative products as project outputs, namely cinnamon yoghurt salad, cowpea tempeh nuggets, red gingerbread, sundubu jjigae with radish-based kimchi, steamed cakes of red dragon glutinous rice tape, braid donuts with fruit glaze Dragon, Dimsum Tempe Bogor Beans, and Frozen Sweet Corn Green Bean Yogurt. Of the 8 products, the panelists liked the red dragon skin glutinous tape steamed sponge cake the most (7.50), so it has the potential to be developed further, while the least preferred product was dimsum tempeh Bogor kacang (4.93). Based on the results of the questionnaire, 100% of students felt that Project Based Learning was effectively applied to fermentation technology courses, could increase motivation and interest in learning, and made it easier for students to understand the material. In addition, 99% of students feel optimistic about achieving competence in the field of food quality assurance, especially controlling fermented food production according to established competency standards, improving design skills and soft skills including teamwork, problem solving, and analytical skills.

Probiotic microorganisms – Propionibacterium ssp

Propionic acid bacteria belong to probiotic microorganisms, probiotic properties of which have not yet been thoroughly investigated. The research describes the probiotic features of milk propionic acid bacteria, including growth at high acidity, tolerance to bile acid, ability to suppress pathogenic microorganisms, and antibiotic susceptibility, as well as the ability to extend the shelf life of various fermented milk products due to the synthesis of propionic acid. Propionic acid bacteria have a robust nature, which makes it easy to overcome technological difficulties in the process of optimizing production. This enables them to be used in the future for the production of various fermented probiotic foods.

The Rendering of Traditional Fermented Foods in Human Diet: Distribution of Health Benefits and Nutritional Benefits

Most fermented foods are based on the cultural preferences of different geographical areas and the heterogeneity of traditions from where they are produced. For instance, many consumers in Asian countries prefer fermented seafood, while consumers in Europe prefer fermented cereal and dairy food products. Even though the food industry has developed various novel techniques in order to produce novel foods (genetic modification, nanotechnology and other processing techniques), traditional foods still represent a significant proportion of the food industry, which has recently appeared to develop further. In addition, the progress in various developed analytical techniques has revealed new knowledge that documents and corroborates certain benefits of traditional foods, mostly regarding their nutritional and health benefits. In this context, the main target of this Special Issue is to deliver new data on how traditional foods exhibit their health-promoting properties and ameliorate the nutritional value of fermented food systems. In addition, the involvement of wild starter culture in the production of traditional foods is a subject area that must be highlighted.

Macronutrients, Amino and Fatty Acid Composition, Elements, and Toxins in High-Protein Powders of Crickets, Arthrospira, Single Cell Protein, Potato, and Rice as Potential Ingredients in Fermented Food Products

Due to the increasing global population and climate change, new sustainable food sources are being intensively sought to replace less favorable livestock production. Especially new protein sources and their food applications are being focused on. In this paper, several selected protein sources that may have potential application in future functional foods, such as fermented foods, were examined and compared. These sources include single cell protein (SCP), Arthrospira platensis (Algae), Acheta domesticus (edible insect), potato, and rice protein. The above sources were compared to whey proteins. The parameters studied were total nutritional value, amino acid profile, fatty acid profile, the content of some elements, and the presence of toxins.

Prevalence of macrolide-lincosamide-streptogramin resistant lactic acid bacteria isolated from food samples.

Lactic acid bacteria (LAB) being a reservoir of antibiotic resistance genes, tend to disseminate antibiotic resistance that possibly pose a threat to human and animal health. Therefore, the study focuses on the prevalence of macrolide-lincosamide-streptogramin- (MLS) resistance among LAB isolated from various food samples. Diverse phenotypic and genotypic MLS resistance were determined among the LAB species (n = 146) isolated from fermented food products (n = 6) and intestine of food-producing animals (n = 4). Double disc, triple disc diffusion and standard minimum inhibitory concentration (MIC) tests were evaluated for phenotypic MLS resistance. Specific primers for MLS resistance genes were used for the evaluation of genotypic MLS resistance and gene expressions using total RNA of each isolate at different antibiotic concentrations. The isolates identified are Levilactobacillus brevis (n = 1), Enterococcus hirae (n = 1), Limosilactobacillus fermentum (n = 2), Pediococcus acidilactici (n = 3), Enterococcus faecalis (n = 1). The MIC tests along with induction studies displayed cMLSb, L phenotype, M phenotype, KH phenotype, I phenotype resistance among MLS antibiotics. Genotypic evaluation tests revealed the presence of ermB, mefA/E, msrA/B and msrC genes. Also, gene expression studies displayed increased level of gene expression to the twofold increased antibiotic concentrations. In the view of global health concern, this study identified that food samples and food-producing animals represent source of antibiotic resistant LAB that can disseminate resistance through food chain. This suggests the implementation of awareness in the use of antibiotics as growth promoters and judicious use of antibiotics in veterinary sectors in order to prevent the spread of antibiotic resistance.

The physicochemical properties of soy sauce made from tempeh

Tempeh is a fermented product that uses Rhizopus sp. to bind raw material into a sliceable cake. Soy sauce is a fermented food product with umami and salty flavor made by Aspergillus sp. for koji fermentation and then soaked in salted water. Tempeh has a shelf life of three days, but soy sauce has a shelf life of six months at room temperature. Therefore, we can increase the shelf life of unconsumed tempeh by turning it into soy sauce. This study compared the physicochemical properties of soy sauce made from tempeh. This study has two variables: length of tempeh fermentation times (three days and four days) and salt solution concentration (15%, 20%, 25%). We also use soy sauce made from soybean with Aspergillus sp. as a positive control. After the soy sauce was fermented for one month, pH, total dissolved solids, °Brix value, yield, color, acceptance test and just-about-right test were analyzed. Results from the acceptance analysis showed that soy sauce made from 3-days tempeh with 20% of salt has significantly higher acceptance compared to other sample with value of 5.37±1.73 (range 1-9) with represent neutral. This soy sauce has pH of 6.73±0.06, total dissolved solids of 9.73 ± 0.02% with 11.7 ± 0.02°Brix. For color analysis, soy sauce made from 3-days tempeh with 20% of salt showed higher lightness than soy sauce made from koji with 20% of salt. Meanwhile for just-about-right test, very salty taste attribute needs to be reformulated.

Comparative Study on Nutrient Composition, Functional Property and Glycaemic Index of “Ogi” in Healthy Rats Prepared from Selected Cereal Grains

One of the most common traditional fermented food products consumed by all class of people in Southern part of Nigeria is Ogi. Ogi is a gurel made from different types of cereal ranging from maize, sorghum, millet among others. Hence, this study was aimed to evaluate nutrient, phytochemicals, functional properties, and glycemic index of Ogi produced from different grains. Grains such as yellow maize (YM), white maize (WM), popcorn maize (PC), red sorghum (RS), white sorghum (WS) and finger millet (FM) were processed into Ogi samples, packaged in airtight container prior to analysis and stored at –20 °C. Proximate results showed that Ogi sample produced from PC significantly contained the highest protein content followed by sample YM. Potassium was observed to be the most abundant mineral elements in Ogi (14.50–19.10 mg/100 g). The phytochemical composition (mg/g) of the experimental samples ranged from 0.34–1.62, 53.82–177.09, 0.00–0.10, 3.71–69.22 and 2.08–6.08 mg/g in oxalate, saponin, flavonoid, phytate and tannin, respectively. The glycemic index ranged 48.83% in YM to 50.71% in WS, while the glycemic load ranged 31.96% in YM to 37.82% in WS, respectively. The result revealed that Ogi samples, especially YM was high in calcium, Ca/P ratio, iron, zinc but low in phytate and tannin content. Sample YM also exhibit lower glycemic index, when compared with other Ogi samples. Hence, YM may be a better grain for the production of Ogi samples.

Fermented Foods of Korea and Their Functionalities

Fermented foods are loved and enjoyed worldwide and are part of a tradition in several regions of the world. Koreans have traditionally had a healthy diet since people in this region have followed a fermented-foods diet for at least 5000 years. Fermented-product footprints are evolving beyond boundaries and taking the lead in the world of food. Fermented foods, such as jang (fermented soybean products), kimchi (fermented vegetables), jeotgal (fermented fish), and vinegar (liquor with grain and fruit fermentation), are prominent fermented foods in the Korean culture. These four major fermented foods have been passed down through the generations and define Korean cuisine. However, scientific advancements in the fermentation process have increased productivity rates and facilitated global exports. Recently, Korean kimchi and jang have garnered significant attention due to their nutritional and health-beneficial properties. The health benefits of various Korean fermented foods have been consistently supported by both preclinical and clinical research. Korean fermented foods effectively reduce the risk of cardiovascular and chronic metabolic diseases, such as immune regulation, memory improvement, obesity, diabetes, and high blood pressure. Additionally, kimchi is known to prevent and improve multiple metabolic diseases, including irritable bowel syndrome (IBS), and improve beneficial intestinal bacteria. These functional health benefits may reflect the synergistic effect between raw materials and various physiologically active substances produced during fermentation. Thus, fermented foods all over the world not only enrich our dining table with taste, aroma, and nutrition, but also the microorganisms involved in fermentation and metabolites of various fermentations have a profound effect on human health. This article describes the production and physiological functions of Korean fermented foods, which are anticipated to play a significant role in the wellness of the world’s population in the coming decades.

Beneficial features of pediococcus: from starter cultures and inhibitory activities to probiotic benefits.

Pediococci are lactic acid bacteria (LAB) which have been used for centuries in the production of traditional fermented foods. There fermentative abilities were explored by the modern food processing industry in use of pediococci as starter cultures, enabling the production of fermented foods with distinct characteristics. Furthermore, some pediococci strains can produce bacteriocins and other antimicrobial metabolites (AMM), such as pediocins, which are increasingly being explored as bio-preservatives in various food matrices. Due to their versatility and inhibitory spectrum, pediococci bacteriocins and AMM are being extensively researched not only in the food industry, but also in veterinary and human medicine. Some of the pediococci were evaluated as potential probiotics with different beneficial areas of application associated with human and other animals' health. The main taxonomic characteristics of pediococci species are presented here, as well as and their potential roles and applications as starter cultures, as bio-preservatives and as probiotic candidates.

Characterization of Bacillus subtilis bacteriophage BasuTN3 isolated from Thua Nao, a thai fermented soybean food product.

The infection of bacteriophage is of great concern in food industry as this can result in complete fermentation failure. In this study, a virulent bacteriophage, named BasuTN3, was isolated from Thua Nao, a Thai fermented soybean. The stability of BasuTN3 was evaluated under various ranges of temperature, pH, chloroform, UV, and disinfectants. The results showed that the isolated BasuTN3 appeared to be specific to its bacterial host, which was identified as Bacillus subtilis strain TN3 based on the 16S rRNA gene sequence analysis. Under TEM, the BasuTN3 belonged to the family Myoviridae. The isolated BasuTN3 could withstand wide temperature ranges (4-45°C) and pH conditions (5-11). The BasuTN3 was susceptible to chloroform, UV, and commonly used disinfectants. The results obtained expand the knowledge of the Bacillus bacteriophage diversity in the fermented soybean products and provide useful information for the bacteriophage and its bacterial starter cultures.

SPME-GC-HRTOF-MS dataset of fermented maize flour volatilome

Background: The volatilome of fermented food products are essential metabolites that significantly contribute to such foods’ overall composition and sensorial quality. The dataset presented herein represents the volatilome of raw and fermented maize flour samples. Methods: Maize grains were milled and naturally fermented at 35°C into sourdough at different periods (24, 48 and 72 h) and, at each point, the profile of the volatiles was investigated. Samples at the different fermentation periods were analyzed using solid phase microextraction coupled with a gas chromatography-high resolution time of flight-mass spectrometry (SPME-GC-HRTOF-MS). Results: Data obtained were classified into different compound groups such as alcohols, aldehydes, aromatic compounds, esters, organic acids, terpenes, ketones, among others and their characteristics such as the retention time, observed mass, molecular formular, mean peak areas and mass spectra also presented. Conclusion: These datasets of fermented maize volatilome can be used as biomarkers for maize fermentation.

Physicochemical Properties and Bacterial Community Profiling of Optimal Mahewu (A Fermented Food Product) Prepared Using White and Yellow Maize with Different Inocula

Mahewu is a fermented food product from maize, commonly consumed in Southern Africa. This study investigated the effect of optimizing fermentation (time and temperature) and boiling time of white maize (WM) and yellow maize (YM) mahewu, with the use of the Box–Behnken-response surface methodology (RSM). Fermentation time and temperature as well as boiling time were optimized and pH, total titratable acidity (TTA) and total soluble solids (TSS) determined. Results obtained showed that the processing conditions significantly (p ≤ 0.05) influenced the physicochemical properties. pH values of the mahewu samples ranged between 3.48–5.28 and 3.50–4.20 for YM mahewu and WM mahewu samples, respectively. Reduction in pH values after fermentation coincided with an increase in TTA as well as changes in the TSS values. Using the numerical multi-response optimisation of three investigated responses the optimal fermentation conditions were observed to be 25 °C for 54 h and a boiling time of 19 min for white maize mahewu and 29 °C for 72 h and a boiling time of 13 min for yellow maize mahewu. Thereafter white and yellow maize mahewu were prepared with the optimized conditions using different inocula (sorghum malt flour, wheat flour, millet malt flour or maize malt flour) and the pH, TTA and TSS of the derived mahewu samples determined. Additionally, amplicon sequencing of the 16S rRNA gene was used to characterise the relative abundance of bacterial genera in optimized mahewu samples, malted grains as well as flour samples. Major bacterial genera observed in the mahewu samples included Paenibacillus, Stenotrophomonas, Weissella, Pseudomonas, Lactococcus, Enterococcus, Lactobacillus, Bacillus, Massilia, Clostridium sensu stricto 1, Streptococcus, Staphylococcus, Sanguibacter, Roseococcus, Leuconostoc, Cutibacterium, Brevibacterium, Blastococcus, Sphingomonas and Pediococcus, with variations noted for YM mahewu and WM mahewu. As a result, the variations in physicochemical properties are due to differences in maize type and modification in processing conditions. This study also discovered the existence of variety of bacterial that can be isolated for controlled fermentation of mahewu.

Use of Bacteriocins and Bacteriocinogenic Beneficial Organisms in Food Products: Benefits, Challenges, Concerns.

This review’s objective was to critically revisit various research approaches for studies on the application of beneficial organisms and bacteriocins as effective biopreservatives in the food industry. There are a substantial number of research papers reporting newly isolated bacterial strains from fermented food products and their application as potential probiotics, including partial characterization of bacteriocins produced by these microorganisms. Most of these studies follow scientific community-accepted standard procedures and propose various applications of the studied strains and bacteriocins as potential biopreservatives for the food industry. A few investigations go somewhat further, performing model studies, exploring the application of expressed bacteriocins in a designed food product, or trying to evaluate the effectiveness of the studied potential probiotics and bacteriocins against foodborne pathogens. Some authors propose applications of bacteriocin producers as starter cultures and are exploring in situ bacteriocin production to aid in the effective control of foodborne pathogens. However, few studies have evaluated the possible adverse effects of bacteriocins, such as toxicity. This comes from well-documented reports on bacteriocins being mostly non-immunogenic and having low cytotoxicity because most of these proteinaceous molecules are small peptides. However, some studies have reported on bacteriocins with noticeable cytotoxicity, which may become even more pronounced in genetically engineered or modified bacteriocins. Moreover, their cytotoxicity can be very specific and is dependent on the concentration of the bacteriocin and the nature of the targeted cell. This will be discussed in detail in the present review.