Brewing Methods Research Articles

Investigation of Ancient Egyptian Baking and Brewing Methods by Correlative Microscopy

Ancient Egyptian methods of baking and brewing are investigated by optical and scanning electron microscopy of desiccated bread loaves and beer remains. The results suggest that current conceptions about ancient Egyptian bread and beer making should be modified. Bread was made not only with flour from raw grain, but sometimes also with malt and with yeast. Brewing blended cooked and uncooked malt with water; the mixture was strained free of husk before inoculation with yeast.

VARIATION IN pH AND LACTATE LEVELS IN MALTS

Malt pH, defined as the pH of worts prepared by the Institute of Brewing Methods of Analysis, was examined in commercial malts from a single malting plant over four crop years, 1990 to 1993. Batch to batch variability was found, in addition to a distinct pattern within two of the years, with a gradual decrease in the winter months following commencement of malting of the new crop barley, followed by a subsequent increase in the late summer. Variability in pH and the longer term trend were not related to any measured processing variables or characteristics of the barley used for malting. Possible reasons for the differences in pH were examined and a negative relationship between malt pH and wort lactate content was demonstrated in a selection of malts from two crop years. A method is proposed for extraction and purification of lactate directly from malt and using this method it was shown that lactate in wort derives mainly from malt with only small amounts being produced during mashing.

Tea preparation and its influence on methylxanthine concentration

The amount of tea or coffee estimated from the number of cups consumed is frequently used as an indication of caffeine consumption in epidemiologic studies. However, this alone may be an inadequate indication of intake since drinking practices of tea varies. In this study, methylxanthine (caffeine, theobromine, and theophylline) contents in three brews of four types of tea (black, oolong, green, and herbal) in both bags and loose leaf forms were investigated to determine the actual amount of methylxanthines present in tea as a function of different brewing methods. On a dry leaf weight basis, total caffeine after three brews was highest in black (32.8 mg/g) and green (36.6 mg/g) tea leaves and lowest in Formosa oolong tea 2 (23.8 mg/g). Total theobromine was highest in black teas (1.64 and 1.69 mg/g) and least in oolong teas (0.65 and 0.71 mg/g). Caffeine and theobromine were not detected in either herbal tea samples, and theophylline was not detected in any tea tested. The overall average caffeine released in the first through third brews were 69%, 23%, and 8%, respectively. Three cups of tea brewed using three tea bags (Western culture) have approximately twice the amount of methylxanthines as the same volume prepared by three successive brews of loose tea leaves (Asian culture). These differences should be accounted for by the epidemiologic studies evaluating the effect of methylxanthines on health.

Coffee, tea and coronary heart disease

The most likely cholesterol-raising factors in unfiltered coffee are kahweol and cafestol. Different brewing methods alter the concentrations of these diterpenes and have caused discrepant results in studies from different parts of the world. The effect of tea on the risk of coronary heart disease is much less clear but some studies have found a protective effect, possibly caused by flavonoids acting as antioxidants.

Changes in Nitrogenous Components and Bacterial Counts of Fermented Sardine with Rice-Bran Produced by Warmed Brewing.

FSR, “Iwashinukazuke,” is a fermented fish product which takes over 6 months for ripening. The warmed brewing method is able to shorten the ripening period to 100 days. This study aims at obtaining fundamental qualitative knowledge of FSR using warmed brewing (30°C, relative humidity; 80%). The initial moisture (55.8%), NaCl content (31.2%) and pH (5.79) of FSR decreased to 51.0%, 26.3% and 5.20 after 100-days warmed brewing, respectively. TMA-N, VBN, NPN/TN and Amino-N/TN increased and the non-volatile amines of the FSR also increased during the warmed brewing. TBC, MYC and LAC at 100 days reached 8.7×107, 1.7×105 and 3.0×106, respectively. A sensory evaluation indicated that there was no particular difference except for color (rice-bran and meat) and flavor between the warmed FSR and the commercial FSR.

アンプル仕込みを用いた清酒の簡易醸造

アンプル仕込みを用いた清酒の簡易醸造

A RAPID SMALL SCALE METHOD FOR THE DETERMINATION OF MALT EXTRACT

A rapid, small-scale method was developed using 1 g of ground malt mashed in 10 ml of water at 65°C. The extract was centrifuged and the specific gravity determined using a density meter. The method was compared with an earlier small-scale method and the Institute of Brewing method and was found to have good precision (CV 1.2%). Absolute malt extract values were not significantly different (P = 0.05) from those obtained by the IOB method.

Development of a new sake brewing method using liquefied rice.—Monograph—

Development of a new sake brewing method using liquefied rice.—Monograph—

Coffee and Cholesterol, an Italian Study

In the present study, conducted in northern Italy between 1986 and 1989, the authors investigated the possible association between coffee consumption and serum cholesterol levels in 8,983 subjects, 7,432 men and 1,551 women, managers and employees aged 18-65 years, who were examined during a program of preventive medicine upon an agreement between various companies and the Centro Diagnostico Italiano. Analysis of covariance was used to compare the serum cholesterol levels of the subjects subdivided according to coffee consumption, along with age, body mass index, alcohol consumption, cigarette smoking, and physical activity. An important relation was demonstrated between coffee intake and cholesterol, particularly in the men, the differences in serum cholesterol in the coffee users compared with the nonusers being 6.1 +/- 1.4 (standard error) mg/dl for consumers of 1-3 cups/day (3.4 +/- 1.4 mg/dl after adjustment for age, body mass index, alcohol and cigarette consumption, and physical activity), 9.9 +/- 1.6 mg/dl for those drinking 4-5 cups/day (5.8 +/- 1.6 mg/dl after adjustment), and 14.8 +/- 2.0 mg/dl for those drinking over 5 cups/day (9.6 +/- 2.0 mg/dl after adjustment). This relation remained substantially unvaried when nonsmokers and smokers were analyzed separately. It has been suggested that it is coffee prepared by boiling rather than other methods that has a hypercholesterolemic effect. Our observations demonstrate an interesting relation between coffee and cholesterol, even though the coffee drunk in Italy is mainly filtered and nonboiled. However, our finding is not necessarily in disagreement with the above hypothesis since, when coffee is prepared in the Italian way (with the mocha method), ground coffee is preheated by steam and more importantly, the water passes through the ground coffee at a higher temperature than with the other brewing methods.

Malting and brewing qualities of some Nigerian rice (Oryza sativa L.) varieties and some thoughts on the assessment of malts from tropical cereals

The maiting qualities of six varieties of Nigerian rice were studied and compared with malts from sorghum and barley. A minimum of seven days was necessary for maximum yield of extract from malted rice. The beer brewed from the six rice malts were similar to each other and to those from sorghum and barley in analytical properties. The appropriateness of using methods designed for assessing barley malt should be re-examined for studying malts from tropical cereals. Meanwhile, it should be sufficient to determine the extract and the nitrogen content of the wort using the European Brewing methods to assess a tropical cereal for mall.

4908222 Microwave brewing apparatus and method: Dong Yu, Ajax, Ontario, Canada

4908222 Microwave brewing apparatus and method: Dong Yu, Ajax, Ontario, Canada

米粉の液化・糖化条件の設定

Rice flour of various grades was used as the fourth addition in test brewing of sake in order to find adequate conditions for liquefaction and saccharification, and results were compared with tose obtained from polished rice. Solutions obtained by enzymatic saccharification of rice flour contained adequate amount of glucose and smaller amounts of amino acid as compared with those obtained by ordinary tratment from polished rice. A pilot plant fermentation was carried out using 50 kg polished rice and 5 kg of rice flour under a selected condition. As the result, the quality of the sake prepared with the use of rice flour as the 4 th addition was tha same as that of sake made by ordinary brewing method except that content of iron and the degree of coloration were somewhat higher.

Bioled coffee increases serum low density lipoprotein concentration

The effects of boiled coffee, filtered coffee, and tea on serum lipoprotein lipids and apoproteins were compared in 42 middle-aged hypercholesterolemic subjects (21 men and 21 women). The subjects consumed the beverages, eight cups a day, in random order during successive 4-week periods with 2-week run-in intervals in a crossover design. The diet was kept unchanged. Statistically significant differences were found between the periods in serum total cholesterol ( P <.0001 ANOVA), LDL cholesterol ( P < .01), and apoprotein B ( P < .01) levels. All differences were due to significantly higher levels during boiled coffee as compared with filtered coffee and tea. No statistically significant differences were found between the filtered coffee and tea periods. There were no differences in serum VLDL cholesterol or triglyceride, HDL cholesterol, and apoprotein A-I concentrations between the periods. Consumption of boiled coffee thus increased the concentration of low density lipoprotein in the serum without affecting its lipid-protein composition. The effect seemed to be determined by the method of brewing.

アデニン要求性酵母による桃色清酒の醸造 ＩＶ 桃色にごり酒もろみの発酵および色調管理法

アデニン要求性酵母による桃色清酒の醸造 ＩＶ 桃色にごり酒もろみの発酵および色調管理法

Effect of stationary and aerated brewing methods on qualities of rice vinegar.

Two types of rice vinegar were produced through stationary and aerated processes.(1) With respect to the general chemical components of the rice vinegar, no noticeable difference was found except for specific gravity. (2) The content of amino acids, especially glutamic and aspartic acids and alanine decreased during both the brewing processes. However, histidine in the stationary brewing and proline and arginine in the aerated brewing increased slightly. (3) In contrast, the amounts of non-volatile organic acids remained unchanged through both brewing processes. Gluconic acid was produced only in the aerated brewing process. (4) Ethanol in the aeration brewed vinegar remained longer than in the stationary brewed one. The gas chromatograms of both types of rice vinegar showed no noticeable difference. (5) In the sensory tests, the aeration brewed vinegar was superior to that produced by the stationary method.

A study of caffeine in tea. I. A new spectrophotometric micro-method. II. Concentration of caffeine in various strengths, brands, blends, and types of teas2–3

A new spectrophotometric micro-method for the determination of caffeine in tea is described. This method is then used to evaluate the caffeine content of a variety of brands and blends of bagged and loose hot tea prepared in different strengths and by different brewing methods. In addition, the caffeine content of instant tea, ice tea, and Mr. Coffee automatic tea is evaluated.

Vývoj kontinualizace sladařské a pivovarské výroby v Maďarsku.

Vývoj kontinualizace sladařské a pivovarské výroby v Maďarsku.

Mit Wasserstoff und Sauerstoff gespeiste electrochemische Brennstoffzellen im naturwissen schaftlichen Unterricht: K. J. Euler, VARTA AG, D3000 Hannover, Stöckener Str. 351, Bundesrepublik Deutschland. Energy Conversion10, 81–88 (1970)

China’s long history of alcoholic beverage production can be traced to the beginning of the Neolithic period when feasting with such drinks became essential in ritual and political contexts, thus setting the pattern throughout Chinese history. Recent studies employing multi-disciplinary approaches have generated new data on the early development of alcoholic fermentation in prehistory. This paper synthesizes the current understanding about alcoholic beverage production and consumption in the Yellow River region of north China during the Neolithic period, with a focus on the Yangshao culture (ca. 7000–4700 cal. BP). Discussion topics include the development of beer brewing methods, changing forms of fermentation vessels, symbolic meanings of surface decoration on brewing vessels, settlement layouts and public buildings in relation to feasting activities, alcoholic beverages as a luxury food item associated with emergent elite powers, and the underlying dynamics related to the unprecedented regional expansion of Yangshao communities in association with drinking rituals. The intensified ritual activities involving communal drinking may have been intended to build and expand social networks, sustain intra- and inter-group solidarity and support, as well as to help elites gain and maintain power during a period of climatic fluctuation with diminishing precipitation in north China.

Method of Shoyu Brewing

Method of Shoyu Brewing

A Comparison between British and Continental Brewing Methods

A Comparison between British and Continental Brewing Methods