Application of a Liquid-Liquid Microextraction Method Based on a Natural Hydrophobic Deep Eutectic Solvent for the Extraction of Plastic Migrants from Kombuchas

A vortex-assisted liquid-liquid microextraction, based on a natural hydrophobic deep eutectic solvent made from the monoterpene thymol and octanoic fatty acid, was employed for the analysis of 11 phthalate esters and one adipate in kombucha (a tea-based fermented beverage). Separation and determination were performed using an ultra-high performance liquid chromatography (UHPLC) system coupled to a single quadrupole mass spectrometer. Confirmatory analyses were carried out through UHPLC tandem mass spectrometry. The full method was validated in terms of matrix effect, matrix-matched calibration, sensitivity, recovery, limits of detection and quantification and repeatability. Satisfactory determination coefficients for quadratic calibration curves (≥0.9938), recovery values (67–120%) and limits of detection (0.07–5.45 µg/L) were obtained. Analysis of 26 kombucha samples reported concentrations for dibutyl phthalate and dimethyl phthalate in the range between the limit of quantification (LOQ) and 16.18 ± 1.14 µg/L, although these phthalates were also detected under the LOQ in some of the analyzed samples. Only one of the samples bottled in plastic containers (7) did not present residues while only five of the 19 samples in glass bottles contained any plasticizer. However, the highest concentration was found in a kombucha bottled in food-grade glass. This work represents the first application in which phthalates and adipates are analyzed in kombuchas.

Sustainable Production of Bioethanol by Zymomonas mobilis and Saccharomyces cerevisiae using Rice Husk and Groundnut Shell as Substrates

Background of Study: Plant waste such as rice husk and groundnut shell are generated in large amounts, these waste presents a tremendous pollution to the environment. Worldwide, these wastes are often simply dumped into landfills and oceans or used as animal feeds. The recovery of food processing wastes as renewable energy sources represents a sustainable option for the substitution of fossil energy in order to minimize environmental damages and to meet energy demands of the growing population. Aim: To produce bioethanol from rice husk and groundnut shell using local strains of Zymomonas mobilis and Saccharomyces cerevisiae. Place and Duration of Study: Conducted at the Microbiology Laboratory of Abubakar Tafawa Balewa University Bauchi, Bauchi state, Nigeria, between April to June, 2021. Methods: Groundnut shell and Rice husk were collected from local milling center. The wastes were powdered, sieved and used as carbon source. Proximate composition of the subsrate was done and the total carbohydrate was determined by difference. The sum of the percentage moisture, ash, crude lipid, crude protein and crude fibre was subtracted from 100. Zymomonas mobilis and Saccharomyces cerevisiae were isolated from rotten sweet oranges and locally fermented beverage (‘kunun-zaki’) respectively by growing them on Malt Yeast Peptone Glucose Agar (MYPGA) after which they were further screened for their ability to tolerate ethanol and they serve as organisms for fermentation. The enzyme α- amylase was used for hydrolysis. The fermented substrates were distilled at 78oC and the distillate was collected as bioethanol in a conical flask. UV-VIS spectrophotometer was used to determine the absorbance of each concentration (0, 0.2, 0.4, 0.6 and 0.8cm3) of reducing sugar content of the hydrolysates and the bioethanol produced by developing a standard curve at a wavelength of 491nm and 588nm respectively. The concentration of reducing sugar and bioethanol was determined using a reference line from the Standard curve. Results: Proximate analysis done shows that rice husk have 70.09% carbohydrates while groundnut shell has 65.09% carbohydrates. Groundnut shell yielded the highest reducing sugar of 5.096%. Rice husk yielded the lowest quantity of reducing sugar with a total yield of 2.962%. Maximum concentration of bioethanol of 0.971% was produced from the combination of Saccharomyces cerevisiae and Zymomonas mobilis from groundnut shell. The lowest concentration of 0.121% of bioethanol was produced when Saccharomyces cerevisiae was used on rice husk hydrolysates. The synergistic relationship of Saccharomyces cerevisiae and Zymomonas mobilis yielded the maximum bioethanol when compared with the yield obtained when the organisms were used singly. Zymomonas mobilis produced highest bioethanol content when the organisms are used single. Conclusion: This study demonstrates the potentiality of local strains of Saccharomyces cerevisiae and Zymomonas mobilis isolated from rotten sweet orange and locally fermented beverage (‘kunun-zaki’) to produce bioethanol by fermenting the rice husk and groundnut shell hydrolysates.

Probiotic Fermented Beverage From Macroalgae

We have tested the hypothesis that a fermented beverage from the macroalgae Hydropuntia eucheumatoides exhibits antioxidant and enzymatic activity. The macroalga was hydrolyzed (maximum hydrolysis yield: 78%) with a mixture of the enzymes viscozyme and lactozyme. Then, the hydrolyzate was fermented with Lactobacillus casei and Saccharomyces boulardii. This beverage contained oligosaccharide prebiotics. The lactic acid, acetic acid, ethanol, methanol, cell count, pH, and heavy metal content of the beverage were determined. All tested heavy metals were either not detected (eg, As) or within the US Food and Drug Administration limits (eg, Fe).

Exploring the potentialities of the Mexican fermented beverage: Pulque

Traditional alcoholic beverages are today recognized for their potentialities and benefits to human health. Pulque is likely to be one of the most consumed traditional beverages in Mexico, which is currently being explored by the research community. Different research and applications have been developed towards the full identification and characterization of the compounds and microbiota presented in pulque. Moreover, to improve its commercialization, specific emerging techniques have been proposed and implemented for the processing of such a traditional alcoholic beverage. Therefore, the goal of this review is to release a comprehensive overview of the latest research and developments focused on exploring the pulque. Herein, a particular emphasis has been paid to the relevant studies and findings in the field. Moreover, a clear overview of the microbial, physicochemical composition, elaboration protocols, together with the main parameters influencing its quality, are given. Few applications and processes aiming for its commercialization have been done (e.g., microencapsulation, spray-drying and ohmic treatment); however, within the exploitation of pulque, its main compounds have been implemented towards the enhancement of properties of other commercial products, such as tortilla and bread. Finally, this review provides the current research gaps and recommendations to the new researchers in the field.

Lentilactobacillus kosonis sp. nov., isolated from kôso, a Japanese sugar-vegetable fermented beverage

A novel lactic acid-producing, Gram-stain-positive, catalase-negative and rod-shaped strain, designated as strain C06_No.73T, was isolated from a traditional Japanese fermented beverage called kôso. According to the results of phylogenetic analysis based on 16S rRNA gene sequences, strain C06_No.73T belongs to the genus Lentilactobacillus . The closest type strain was Lentilactobacillus curieae CCTCC M 2011381T, with a sequence identity of 98.1 %. The identity values with other strains were all below 97 %. The isolate propagated under the conditions of 18–39 °C (optimum, 27 °C for 48 h incubation) and pH 4.0–7.0 (optimum, pH 6.5). The G+C content of its genomic DNA was determined to be 37.9 mol%. The main fatty acids were C16 : 0, C18 : 1 ω7c, C18 : 1 ω9c and C19 : 0 cyclopropane 11,12. The major polar lipid was identified as phosphatidylglycerol. No isoprenoid quinone was detected. The predominant cell-wall amino acids were lysine, alanine, glutamic acid and aspartic acid. Neither meso-diaminopimelic acid nor ornithine were detected. On the basis of this polyphasic taxonomic study, the isolate is concluded to represent a novel species, for which the name Lentilactobacillus kosonis sp. nov. is proposed. The type strain is C06_No.73T (=NBRC 111893T=BCRC 81282T).

Review on The Production of Fermented Beverage as a Post-Harvest Processing Alternative For Mango, Banana and Purple Sweet Potato

West Java is one of the regions in Indonesia that produces large numbers of mango, banana, and purple sweet potato. After harvesting, these commodities will undergo physical, chemical, and physiological changes so that further post-harvest processing is needed. One of the post-harvest processing that can be done is fermentation. Fermenting mango, banana, and purple sweet potato into wine is a simple and efficient method that can increase the economic value of the product. Wine is an alcoholic beverage made from grapes; however, any fruit and tuber could be used for wine-making. The article reviews the potential of mango, banana, and purple sweet potato for wine production, the microbes involved, and pretreatments of mango, banana, and purple sweet potato.

Development of Korean Indigenous Low-Temperature-Tolerant Yeast for Enhancing the Flavor of Yakju

Yakju, a traditional fermented beverage in Korea, is prepared using various raw materials and methods, and, hence, exhibits various characteristics. Low-temperature-fermented yakju can inhibit the growth of undesirable bacteria and is known for its unique flavor and refreshing taste. To increase the production of volatile aromatic compounds in yakju, strains with strong resistance to low temperatures and excellent production of volatile aromatic compounds were screened from indigenous fruits (grape, persimmon, plum, aronia, wild grape) and nuruk in Korea. One Saccharomyces cerevisiae and three non-Saccharomyces strains were finally screened, and yakju was fermented at 15 °C through mono/co-culture. The analysis of volatile aromatic compounds showed that S. cerevisiae W153 produced 1.5 times more isoamyl alcohol than the control strain and reduced the production of 2,3-butanediol by a third. Similarly, a single culture of Pichia kudriavzevii N373 also produced 237.7 mg/L of ethyl acetate, whereas Hanseniaspora vineae G818 produced ~11 times greater levels of 2-phenethyl acetate than the control. Alternatively, Wickerhamomyces anomalus A159 produced 95.88 mg/L of ethyl hexadecanoate. During principal component analysis, we also observed that the co-culture sample exhibited characteristics of both volatile aroma compounds of the single cultured sample of each strain. Our results suggest that yakju with unique properties can be prepared using various non-Saccharomyces strains.