The production of ‘Orogo's’ — low alcoholic beverages from plantain (musa paradisica)

A laboratory version of orgoro; a low alcohol plantain beverage was found to possess a better odour, taste and colour after 7 days of fermentation compared with a native brew. The pH of the native brew decreased from 3.90 to 1.93 after 21 days of fermentation while the filterable acidity increased from 0.100 to 0.157%. The laboratory brew showed a decrease of pH from 4.60 to 2.72 and an increase in filterable acidity from 0.250 to 0.485%. Both brews had alcohol contents of 0.109 and 0.197% (v/v) respectively after this period. The total sugars content, soluble protein and total nitrogen contents of the native brew were 2.0 mg/ml, 1.3 mg/ml and 2.05 mg/ml respectively while values for the laboratory brew were 5.0 mg/ml, 2.2 mg/ml and 4.0 mg/ml respectively.     

Production of Chlorflavonin, an Antifungal Metabolite of Aspergillus candidus

Production of chlorflavonin, a new antifungal antibiotic, by strains of Aspergillus candidus is described. Two wild strains of the fungus had distinctly different chlorflavonin-producing capabilities. One strain produced 25 mug of chlorflavonin per ml per 4 to 5 days in a pilot scale fermentor with stirring, using a medium containing corn steep liquor and glucose. Production of antibiotic was favored by high rates of agitation-aeration. Crude chlorflavonin was extracted from the whole brew with a hydrocarbon solvent and then purified by recrystallization from benzene and petroleum ether. The overall yield from fermentation brew to pure product was 50%.     

Role of hydroxycinnamates in coffee melanoidin formation

Melanoidins are the high molecular weight brown end products of the Maillard reaction. They are formed during heat processing of foods like coffee, bread, malt, and beef. A chemical definition of these food polymers is still impossible, despite several efforts to determine their structure. In the last years, the interest in research on melanoidins has increased due to their biological activities. Coffee brew is one of the main sources of melanoidins in human diet. Various melanoidin fractions were obtained by applying chromatographic separation techniques or specific isolation procedures, allowing, a partial view on structural features and diversity of coffee brew melanoidins. Different melanoidin populations can be found with respect to total carbohydrate contents and their structural features. In this paper, the recent advances in research on coffee melanoidin structures and formation mechanisms are reviewed. The participation of hydroxycinnamates in melanoidin formation, especially true for coffee melanoidins, is a hypothesis older than three decades, but only recently more consistent data have been obtained for their presence. Although the role of hydroxycinnamates in melanoidin formation is not yet completely understood, it was demonstrated that the interaction between phenolic compounds and melanoidins can be of non-covalent or of covalent nature. The most likely linkage point is through the protein fragments incorporated in the coffee melanoidin during the roasting process, although carbohydrates, such as arabinose, seem to be possible binding sites for the chlorogenic acid derivatives on these brown structures, too.     

Biochemical analysis as a measure of dynamic equilibrium in genomic setup during processing of tea

The genetic characteristic such as ‘fermentability’ of a tea cultivar could be utilised to obtain maximum colour/bloom during manufacture of black tea. Pigment profile analysis has been used as a tool to assess the characteristic of a black tea brew. Fine plucking and optimum processing conditions are two basic requirements in producing good quality black tea. The assamica variety is characterised by linalool content while geraniol is specific in chinary clones. The higher amounts of terpenoids improved the flavour characteristic of second flush tea of north east India in general and Darjeeling in particular. Further, the surplus fatty acid degradation products lower the quality of black tea during monsoon flush. Presented at the 3rd National Symphosium on Bioorganic Chemistry, 1987, Hyderabad.     

几株啤酒酵母的筛选及发酵性能比较*

啤酒酵母是啤酒酿造的灵魂,可以直接影响啤酒品质。在啤酒酿造过程中,由于啤酒酵母被多次传代和保藏,造成优良菌种发酵性能衰退等问题,导致发酵不彻底,影响最后啤酒的风味质量。为此以8株Lager型啤酒酵母为出发菌株,通过平板分离纯化获得80株分离菌株,再经过三角瓶发酵初筛和复筛、发酵罐中试发酵实验最终获得了8株发酵性能优良的啤酒酵母。其中,6株酵母可应用于酿造双乙酰含量低于0.1 mg/L的啤酒;3株酵母发酵度高于70%,适合酿造干啤酒;1株酵母发酵度低于50%,适合酿造低醇啤酒。在风味方面:1株酵母酿造的啤酒醇酯比为3.3,啤酒酯香味较突出;另1株酵母酿造的啤酒醇酯比为4.5,啤酒高级醇含量较高。8株经过选育的啤酒酵母发酵特征明显,便于精酿啤酒厂实际应用。     

Acute Biphasic Effects of Ayahuasca

Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca''s compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8–13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30–50 and 50–100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca’s chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it''s potential therapeutic effects is offered.     

Multicenter evaluation of prototype real‐time PCR assays for Epstein‐Barr virus and cytomegalovirus DNA in whole blood samples from transplant recipients

Quantitative PCR is becoming widespread for diagnosing and monitoring post‐transplantation diseases associated with EBV and CMV. These assays need to be standardized to manage patients in different facilities. Five independent laboratories in Japan compared home‐brew assays and a prototype assay system to establish a standard quantitative procedure for measuring EBV and CMV. Reference standards and a total of 816 (642 EBV and 174 CMV) whole blood samples from post‐transplantation recipients were used for this multicenter evaluation. The prototype reference standard for EBV was compared to a panel of samples, with a theoretical expected value made using EBV‐positive cells containing two virus genome copies per cell. The mean ratio of the reference standard at each site to the standard of the prototype assay was ≤4.15 for EBV among three different sites and ≤3.0 for CMV between two laboratories. The mean of the theoretical expected number of the EBV genome: prototype reference was close to 1.0. The correlation coefficients between the viral copy numbers determined using the prototype assay and those using each home‐brew assay were high (EBV, 0.73–0.83, median = 0.78; CMV, 0.54–0.60, median = 0.57). The dynamics of the EBV and CMV loads in transplant recipients were similar between the assay types. There was an inter‐laboratory difference among the quantification results, indicating that a unified protocol and kit are favorable for standardizing the quantification of EBV and CMV. Such standardization will help to standardize the diagnosis and monitoring of diseases associated with EBV and CMV.     

Black tea represents a major source of dietary phenolics among regular tea drinkers

The phenolic composition and antioxidant activities [TEAC, ORAC, FRAP] of consumer brews (1 tea bag in 230 ml for 1 min) of seven different brands of black tea from the British market were investigated. The main phenolic compounds identified were epigallocatechin gallate, four theaflavins, as well as epicatechin gallate, theogallin (tentative assignment), quercetin-3-rutinoside and 4-caffeoyl quinic acid. Thearubigins represented an estimated 75-82% of the total phenolics. Further, polyphenol fractions were in decreasing order theaflavins, flavan-3-ols, flavonols, gallic acids and hydroxycinnamates. On average, a cup of a consumer brew of black tea is providing polyphenols at the level of 262 mg GAE/serving, of which 65 mg were assigned to individual polyphenols. The antioxidant activity of black tea preparations is higher than that of most reported dietary agents on a daily basis. Correlations were observed between the antioxidant activities and the sum of all quantified polyphenols by HPLC analysis as well as with the total phenolics. Treatment of the black tea brew with simulated gastric juice resulted in a significant increase of the identified theaflavins implying a partial cleavage of thearubigins in the environment of the gastric lumen. Therefore, black tea can be considered to be a rich source of polyphenols and/or antioxidants.     

Black Tea Represents a Major Source of Dietary Phenolics Among Regular Tea Drinkers

The phenolic composition and antioxidant activities [TEAC, ORAC, FRAP] of consumer brews (1 tea bag in 230 ml for 1 min) of seven different brands of black tea from the British market were investigated. The main phenolic compounds identified were epigallocatechin gallate, four theaflavins, as well as epicatechin gallate, theogallin (tentative assignment), quercetin-3-rutinoside and 4-caffeoyl quinic acid. Thearubigins represented an estimated 75-82% of the total phenolics. Further, polyphenol fractions were in decreasing order theaflavins, flavan-3-ols, flavonols, gallic acids and hydroxycinnamates. On average, a cup of a consumer brew of black tea is providing polyphenols at the level of 262 mg GAE/serving, of which 65 mg were assigned to individual polyphenols. The antioxidant activity of black tea preparations is higher than that of most reported dietary agents on a daily basis. Correlations were observed between the antioxidant activities and the sum of all quantified polyphenols by HPLC analysis as well as with the total phenolics. Treatment of the black tea brew with simulated gastric juice resulted in a significant increase of the identified theaflavins implying a partial cleavage of thearubigins in the environment of the gastric lumen. Therefore, black tea can be considered to be a rich source of polyphenols and/or antioxidants.     

Environmental Implications of Consumer Convenience: Coffee as a Case Study

Products of convenience are playing an increasingly large role in today's society. These products provide a competitive advantage over their conventional counterparts by requiring less time and effort to produce a similar service or experience. At the same time, these products are often also more materials intensive to produce and create a greater amount of waste. A comparative midpoint life cycle assessment of different coffee brewing systems is presented in order to explore the comparative impact of three different systems: drip filter, french press, and pod style (a product of convenience). Utilizing a comparative functional unit, the drip filter system method was found to have the greatest environmental impact in all impact categories, whereas the pod style had the least in six of the impact categories (with the french press having the least in two of the impact categories, and a tie between pod style and french press in a single impact category). This suggests that contrary to popular belief, the pod style coffee may be the more environmentally friendly option. The two most significant contributors to environmental impact in all of the categories considered was the amount of dry coffee utilized and the energy needed to brew the coffee, although in some categories considered transportation was also significant. There is the potential for the environmental impact of coffee brewing to shift if coffee wastage occurs (likely in the case of the drip filter and french press system) or if substantial changes in materials or energy consumption were to occur (in the case of the pod‐style brewing system). From the perspective of industrial ecology, this analysis suggests that, in regard to products of consumer convenience, the convenient alternative may not have a significantly greater environmental impact than its conventional counterpart, and that it may be time to question that often‐held assumption.     

Antioxidative activity of a zinc-chelating substance in coffee

Coffee brew contains a brownish zinc-chelating polymer designated ApV. ApV was prepared from the precipitate formed in a solution of instant coffee by adding ZnCl(2) and purified using ion-exchange and cellulose column chromatographies. The antioxidative activities of ApV and related compounds were evaluated in this study. The free-radical scavenging activity of ApV estimated by ABTS assay was at a similar level to that of instant coffee, while the O(2)(-) scavenging activity of ApV, which is superoxide dismutase-like activity, was lower than that of instant coffee. The hydroxyl-radical scavenging activity of ApV was higher than that of instant coffee, and the auto-oxidation of linoleic acid was more strongly inhibited by ApV than by caffeic acid.     

Detection of BRAF V600 Mutations in Melanoma: Evaluation of Concordance between the Cobas? 4800 BRAF V600 Mutation Test and the Methods Used in French National Cancer Institute (INCa) Platforms in a Real-Life Setting

Vemurafenib is approved for the treatment of metastatic melanoma in patients with BRAF V600 mutation. In pivotal clinical trials, BRAF testing has always been done with the approved cobas 4800 BRAF test. In routine practice, several methods are available and are used according to the laboratories usual procedures. A national, multicenter, non-interventional study was conducted with prospective and consecutive collection of tumor samples. A parallel evaluation was performed in routine practice between the cobas 4800 BRAF V600 mutation test and home brew methods (HBMs) of 12 national laboratories, labelled and funded by the French National Cancer Institute (INCa). For 420 melanoma samples tested, the cobas method versus HBM showed a high concordance (93.3%; kappa = 0.86) in BRAF V600 genotyping with similar mutation rates (34.0% versus 35.7%, respectively). Overall, 97.4% and 98.6% of samples gave valid results using the cobas and HBM, respectively. Of the 185 samples strictly fulfilling the cobas guidelines, the concordance rate was even higher (95.7%; kappa = 0.91; 95%CI [0.85; 0.97]). Out of the 420 samples tested, 28 (6.7%) showed discordance between HBM and cobas. This prospective study shows a high concordance rate between the cobas 4800 BRAF V600 test and home brew methods in the routine detection of BRAF V600E mutations.     

果胶酶分离纯化及分析方法的研究进展

果胶酶能降解果胶质,在果汁制造、果酒酿造等方面有着广泛应用。果胶酶分子生物学的迅速发展极大地促进了分离纯化与分析方法的研究。由于不同菌种产生的果胶酶成分复杂程度不同,分离纯化手段和分析方法也不相同。本文对果胶酶分离纯化手段及其分析方法进行了综述。     

Improved brewing of millet beer – (OYOKPO) and production of single cell proteins from the spent grain

The improved method for preparing Oyokpo a Nigerian fermented beverage from millet, and the preparation of single cell proteins from the spent grain is described. Improvement of the brew was made by controlled malting, mashing and brewing with a pure culture of Saccharomyces cerevisiae. It had a reducing sugar content of 19.73 g/100 ml before fermentation and after fermentation 5.56% alcohol, 0.58 g/100 ml titratable acidity as acetic acid, a final pH of 4.2 and consisted of a yellowish clear liquid, slightly sour. The native brew had a reducing sugar content of 7.37 g/100 ml before fermentation and after fermentation, 2.40% alcohol, 0.43 g/100 ml titratable acidity, a final pH of 3.8 and consisted of a creamy yellowish liquid with a very sour taste. Fermented spent grain gave a higher protein yield compared to unfermented or ground millet. The lipids, proteins and crude fibre were 4.94%, 11.20% and 4.33% respectively for ground millet, 12,79%, 23.77% and 19.46% respectively for unfermented spent grain and 19.61%, 47.28% and 32.09% respectively for fermented spent grain. The high protein and fibre content of the fermented spent grain points to its potential as a feed supplement for ruminants.     

Preliminary Study of Fat Oxidation in Sorghum and Maize Brewing

Superoxide dismutase (SOD) activity in the white sorghum farafara and ICRISAT sorghum variety – ICSV 400 was at a high activity in the embryo at about 8 SOD units/tissue. This activity was almost completely destroyed at 80 °C. Totox index of the brewing grains were 366 for ICSV 400, 312 for farafara, 112 for maize grits and 90 for barley malt. Worts from sorghum/maize and sorghum/barley malt brews all had hydroperoxy linoleic acid (15–19 μM) which remained undetected after wort boiling. Sorghum/maize brews formed very little trub (wort proteinous sediments) in the whirlpool and trub increased in sorghum/barley brews with increased usage of barley malt. Sorghum/maize brews had free fatty acids (FFA) at 22 mg/l in pitching wort but in sorghum/barley brew (50/50) only 9 mg/l. This revised version was published online in July 2006 with corrections to the Cover Date.     

Simultaneous control of apparent extract and volatile compounds concentrations in low-malt beer fermentation

Volatile compounds cause undesirable flavor when their concentrations exceed threshold values in beer fermentation. The objective of this study is to develop a system for controlling apparent extract concentration, which indicates the fermentation degree and which should be decreased below a targeted value at a fixed time under a constraint of tolerable amounts of volatile compounds. In beer fermentation, even though the production of volatile compounds is suppressed by maintaining a low fermentation temperature, a low temperature causes a delay in the control of apparent extract concentration. Volatile compound concentration was estimated on-line, and the simulation of apparent extract consumption and volatile compound production was performed. To formulate various beer tastes and conserve energy for attemperation, optimal temperature profiles were determined using a genetic algorithm (GA). The developed feedback control of the brewing temperature profile was successfully applied, and apparent extract and volatile compound concentrations at a fixed time reached their target concentrations. Additionally, the control technique developed in this study enables us to brew a wide variety of beers with different tastes.     

The Food of Elders, the "Ration" of Women: Brewing, Gender, and Domestic Processes among the Samburu of Northern Kenya

In recent years, many Samburu women have begun to brew beer and liquor for sale to elders—including their own husbands. Drawing on "cooperative conflict" approaches to domestic processes, the essay examines brewing in reference to the economic and cultural position of men and women within Samburu households and society at large. Focusing in particular on the issues posed to each gender by the differential control of key resources by the other—food by women and cash by men—the essay views brewing as a negotiated structure through which men and women address the particular gender-based problems they encounter in daily life. [ gender, family, brewing, Africa ]     

酸性蛋白酶在酱油酿造中的应用研究

低盐固态酿造酱油,在发酵过程中pH偏酸。采用在发酵中期添加适量的酸性蛋白酶,弥补在制曲时米曲霉所产生的酸性蛋白酶活性的不足。增强在酸性环境下对蛋白质的分解作用,提高原料蛋白质的利用率,增产酱油8.0％左右。     

SELECTION OF AN ASTRINGENCY REFERENCE STANDARD FOR THE SENSORY EVALUATION OF BLACK TEA

Astringent and bitter sensations are characteristic sensory qualities of black tea. Three different classes of potential astringent reference standards (two concentrations each of alum and tannic acid and three fruit juices) were evaluated in this study. The perceived astringency, bitterness and sourness of each were profiled using computerized time-intensity and compared with the astringent intensity of a standardized brew of black tea. The differences in temporal profiles of potential reference standards across taste attributes were evident and intensity ratings were found to be dependent upon the stimulus and its concentration. Both concentrations of tannic acid were evaluated as the highest in perceived bitterness. For the juices, a strong sour taste was perceived in addition to astringency. It was concluded that the best reference standard for the astringency of black tea is a solution of 0.7 g/L alum as it is low in perceived bitterness and sourness.     

Yeasts in the traditional brewing of pito in Ghana

Yeasts from pito, a cereal-based traditional alcoholic beverage were isolated and characterized using biochemical and physiological tests. A total of 21 strains belonging to 8 genera were identified as Saccharomyces cerevisiae (8), Candida tropicalis (4), Kloeckera apiculata (2), Hansenula anomala (2), Torulaspora delbrueckii (3), Schizosaccharomyces pombe (1) and Kluvyeromyces africanus (1). Various diluents used for a 2 h holding period shows that 0.1% malt extract and peptone gave 20% decrease in cell viability for all the isolates, while phosphate buffer least supported the survival of the yeast cells with about 90% decrease in cell viability obtained for S. pombe at the end of the 2 h holding period. The effect of pH and temperature on the growth of the isolates revealed that at relatively low temperatures, growth increased with increasing pH, but a decrease was observed with increasing pH at high temperatures for S. cerevisiae and Candida tropicalis. All the isolates demonstrated good growth (10² to 10⁶ c.f.u./ml) at 10% ethanol concentration over a period of 8 days incubation. However, growth of K. africanus was completely inhibited after 4 days incubation period. The quality indices of the beverage produced using S. cerevisiae as a single-starter organism compared favourably with the traditional brew. The paper suggests ways of scientifically regulating the production of fermented foods in sub-Saharan Africa.