ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A new method for determination of nutritive value of the foodstuffs used in industrial alcohol distilleries

I. Štein

Research Dept., Food Ind., Bratislava

Abstract: An aq. ext. of foodstuffs, prepd. under the same conditions as in a com. distillery, contg. 0.1 g. sol. N, is dild. to 100 ml. and added to 400 ml. of 10% sucrose soln. at 30° and inoculated with 10 g. of normal compressed yeast. A blank is made under the same conditions with 100 ml. of H₂O. The vol. of CO₂ is detd. by the Kusser method and recorded every 30 min. for 3 hrs. starting with the first drop of water. The activity index (A1) is calcd. by subtracting the vol. of CO₂ formed after 60 min. and dividing by 120; i.e. the vol. of CO₂ formed in 1 min. If A₂ is the activity index of the blank, then the activated fermentation K is A1 - A2. By processing 10 g. of compressed yeast by the same method, but weighing CO₂ (fx) after 24 hrs. fermentation at 30°, the activation of the fermentation strength can be calcd. as F = fx - fy, fy being the value of the blank. The solns., including blank remaining after the detn., are filtered or centrifuged, and yeast is washed with physiol. soln. of NaCl and H₂O and dried by filter paper to normal consistency. The protein metabolism of yeast (N) is based on the percentage of N which was not consumed (nx) and calcd. from N = nx - ny; ny is the value of the blank. The theoretical value of the nutrient can be expressed by the factor S = K + F + N. If S is based on the amt. of the nutrient in 100 g. of the dry substance contg. 0.1 g. of the sol. N, then the nutritive value of the foodstuff is St = 10 × sol. N in 100 g. of dry substance × S. St factors for some of the foodstuffs are given: 'ferment-suforin' 575.36, dried yeast 410.84, green malt 128.44, malt flower 222.77, 'diaspirit' 61.44, barley 9.9, and rye 23.03. The foodstuffs most currently used in com. practice were compared with green malt in regard to nutritive value and amt. needed to produce the same biol. effect in fermentation.

Full paper in Portable Document Format: 35-6a168.pdf (in Slovak)

Chemical Papers 3 (5-6) 168–205 (1949)