Mash temperature

Wahjudi, J., Xu, L., Wang, P., Singh, V., Buriak, P., Rausch, K.D., McAloon, A.J., Tumbleson, M.E., and Eckhoff, S.R. 2000. Quick fiber process Effect of mash temperature, dry solids and residual germ on fiber yield and purity. Cereal Chem. Tl, 640-644. 

This beer is of the Grand Cm style and has a tremendous orange nose. There is some residual sweetness due to moderately high mash temperature. It is a beautiful light color. I make this beer yearly as a special drink for the winter holidays. By substituting some honey for pale malt, it makes a nice change and adds more complexity. I have also simply added 5 pounds of honey to make a real blockbuster of a Grand Cru This beer recipe is in its 5th version. 

I found this to be a nice change of pace from the pale ale and stout rut that homebrewers often get caught up in. I used a mixed culture to minimize the clove character of 3056 while still allowing some of it to come through. The Irish moss is not important in this recipe, as cloudiness is an acceptable characteristic of this style. Additionally, any noble hop is acceptable to bitter with. I just happen to have an ounce of Kent Goldings around. Attention should be paid to keep the correct mash temperatures, as this beer should have a dry finish. I found the honey to be a subtle touch which almost goes unnoticed. You ll enjoy this one. 

If mash temperatures in the brewhouse fall or sweet wort is held at temperatures below 60 C (140°F), there is a danger that thermophilic bacteria will... 

In infusion mashing, used mostly in England for brewing top fermented beer, the terminal mashing temperature is achieved not by stepwise increases, but by live steam injection or addition of hot water. As in the decoction method, the temperature program used can vary greatly. 

Fig. 1. Properties of foods near 2.45 GHz as a function of temperature, where A represents distilled water B, cooked carrots C, mashed potatoes D, cooked ham E, raw beef F, cooked beef and G, com oil (a) dielectric constants and (b) load factors, e = etan6 (32).

Fig. 6. Temperatures for a three-mash method. The soHd line shows the temperature in the three-mashes that are boded. The dashed line shows the temperature in the rest or whole mash, as the temperature is brought from mashing-on to mashing-off...

In a two-mash method, mashing-in is at ca 50°C. A first cook-mash brings the temperature to 60—65°C, and a second mash to 75—78°C. This method is used to obtain a wort of light color and good quaUty. 

In a one-mash method mashing-in is usually at 60—65°C, holding this temperature for some time in the whole mash and then bringing the temperature to 75—78°C with the aid of one cook-mash. 

Mixed Methods. These are combinations of decoction and infusion methods. The mashing-in can be at 35—40°C, whereupon a cook-mash is drawn which, after having been boiled, brings the temperature to 60—65°C. After being held here for some time the whole mash is slowly heated, first to about 70°C then, after a short pause, to mashing-off at 75—78°C. 

Rye. In the preparation of a bourbon mash, rye is not always subjected to the com cooking process. However, rye undergoes Hquefaction at a much lower temperature than com. This avoids thermal decomposition of critical grain constituents adversely affecting the final flavor of the distillate. Rye is often mashed separately. 

Particle size and cooking condition for the grain slurry vary depending on the type of distilled spirit that is to be produced. In the case of com grain fermentations, distillers use small size, high temperature, and low beer gallonage (higher starch concentrations) for neutral spirits production at 120—170°C and 76—91 L/0.03 m. Bourbon distillates call for low temperatures (100—150°C) and thinner mash of 95—115 L/0.03 m (saccharified starch slurries) out of flavor considerations. (0.03 m is approximately a bushel). 

The converted mash is pumped to a clean sterilised fermentor and the yeast inoculum is added. The set temperature range for whiskey fermentation of 72 hours is usually 17—21°C. At the beginning, the mash converted composition is approximately 80% sugars, mainly maltose and some (<1%) dextrose (primary conversion). The pH is adjusted to reduce initial bacterial growth. Grain neutral spidts are usually set at 27—29°C to expedite fermentation. Temperatures above 35°C inhibit yeast reproduction and promote rapid bacterial growth. Above 40°C actual yeast kill occurs. 

A culture of Bacillus polymyxa in a tube with Trypticase soybean broth was incubated overnight at 25°C. 5 ml of this culture was transferred to 100 ml of the tank medium in a 500 ml Erlenmeyer flask which was incubated for 48 hours at room temperature. This 100 ml culture served as inoculum for one tank. During the course of fermentation the medium was aerated at the rate of 0.3 volume of air per volume of mash per minute. The temperature was maintained at about 27 C. Samples of mash were taken every 8 hours in order to determine pH and the presence of contaminants and spores. After 88 hours of fermentation the pH was about 6.3 and an assay using Escherichia coll showed the presence of 1,200 units of polymyxin per cubic centimeter. The polymyxin was extracted and purified by removing the mycelia, adsorbing the active principle on charcoal and eluting with acidic methanol. 

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