Pito is an alcoholic beverage obtained through a yeast (Saccharomyces cerevisiae) fermentation of wort extracted from sorghum (Sorghum bicolor L. Moench) malt. The malting conditions of sorghum are thought to influence the quality characteristics of the malt, and subsequently the quality of the pito obtained from it. Studies were carried out on a local sorghum cultivar grown in Ghana -chireh, to optimize the conditions for malting conditions for pito production in Ghana. A 3 3 full factorial experimental design was replicated with steeping times of 12, 16 and 22 h, germination times of 3, 4 and 5 days, and malt drying temperatures of 30, 40 and 50°C as factors. Diastatic power, extract yield, attenuation limit and free amino nitrogen were determined. Germination duration significantly affected diastatic power and free amino nitrogen (p < 0.001). Extract yield was also significantly influenced by germination duration (p = 0.001). The germination time, steeping time and drying temperature had no significant effect on the attenuation limit. The optimal conditions for malting this specific cultivar grown in Ghana to obtain critical malt quality indices are 12.0-12.5 h steeping, 5 days of germination at 30°C and drying at 40°C. Free amino nitrogen levels in all treatments were higher than the minimum requirement for good yeast nutrition and fermentation.

This paper contains the results of new measurements of the thermal conductivity of mixtures of benzene and 2,2,4-trimethylpentane in the liquid phase within the temperature range 313 to 344 K at pressures up to 350 MPa. The measurements were carried out with a transient hot-wire instrument and have an estimated accuracy of +0.3%. The study is the first conducted at high pressures on mixtures of components of greatly differing volatilities and therefore provides a further test of methods of representing the thermal conductivity of liquid mixtures based upon the hard-sphere theory of transport in liquids. It is shown that the procedure is capable of representing all of the present experimental data within +5%. A more detailed examination of the results reveals small, but systematic, deviations from universality of the behavior of the thermal conductivity as a function of density implied by the hard-sphere theory, which merit further investigation.

several physical and chemical changes occur in the cocoa beans such as evaporation of volatile acids, causing reduction in the acidity hence reducing the sourness as well as bitterness of the cocoa beans. These changes lead to the production of desirable chocolate flavours and colour [2] by maillard reaction. The flavour precursors viz., free amino acids, short-chain peptides, and reducing sugars [3,4] produced during fermentation interact during the roasting to produce the desirable flavour compounds such as pyrazine, alcohols, esters, aldehydes, ketones, furans, thiazoles, pyrones, acids, imines, amines, oxazoles, pyroles, and ethers [5-8]. The quality of the flavours produced is dependent on several factors, such as the origin of the beans, period of harvesting, postharvest treatment, variety and the roasting conditions [4,9-14].

The therlnal conductivily of binary liquid mixtures of water and 2-n-buloxyethanol has been measured widfin the temperature range 3()5 35~) K at pressures t,p IO 150 MPa. The measurements have been carried out with it lransienl hotwire mslrument st,ilable Ibr eleclrieally condt, ctmg liquids and have an estimated accuracy of _+0.3".. The liquid mixture h~,s a closed-loop soluhilily and reveals a lower crilical solution tenlperalure Ibr a mole fraction of 2-1t-buloxyetham,[ of (l.I)47,R at a temperature of 322.25 K. The results of the measurements reveal a SlllilJJ, hi.l| discernible, enhancement of Ihe thermal conductivity o1 the solulion ill tile cri|ical composition.

This work characterized the most cultivated and consumed yam ( Dioscorea ) cultivars within the Ghanaian yam germpla sm based on their biochemical and cell wall constituents to assess their potential alternative food and industrial processing applications. Samples were analyzed for their biochemical composition - starch, amylose, amylopectin, total sugars, reducing sugar s and non- reducing sugars along the head, middle and tail regions of each tuber using standard analytical methods. Cell wall constituents - acid detergent fibre, neutral detergent fibre, acid detergent lignin, cellulose and hemicellulose of each tuber were also determined using standard analytical methods. The results showed no significant differences at p<0.05 in biochemical compositions along the length of the studied cultivars. D. cayenensis (Pure -yellow), D. rotundata (Pona) and D. alata (Matches) were found to have high starch contents (63.16- 65.69%, 63.54- 65.30% and 63.24- 65.17% respectively). Amylose content was observed to vary along the length of the tubers for the varieties studied. D. alata (Matches) was observed to contain the highest amylose con tent of 19.66- 20.64%. No identifiable trend was however, observed for the amylopectin content along the length between the varieties investigated. D. bulbifera recorded the lowest amylopectin content of 41.29%, 43.59% and 44.63% while D. esculenta had the highest with 49.84%, 50.24% and 50.13% along the tail, middle and head sections respectively. Total sugar content varied significantly (p<0.05) along the lengths of all the varieties investigated. It was higher at the tail portions for all the varieties studied than the head regions; the middle portions recorded the least. D. bulbifera recorded highest total sugar contents (4.74- 4.84%) and total sucrose (3.58 -3.64%). There were significant differences ( p<0.05) in the cell wall constituents of the yam varieties. Cellulose was found to be the most common cell wall component with D. rotundata having the highest level of 3.36% whilst D. dumetorum had the least (1.56%). Hemicellulose content ranged between 0.42 g/100g in D. alata to 4.58 g/100g in D. esculenta while lignin content ranged from 1.56 g/100g in D. dumetorum to 2.87 g/100g for D. praehensalis . There were significant differences (p<0.05) in the neutral detergent fibre found in Dioscorea esculenta and the other yam species . It ranged from 1.18 g/100g in D. alata to 5.46 g/100g in D. esculenta . Less than 1% of acid detergent fibre was identified in the yam varieties , suggesting varied levels of biochemical composition and cell wall constituents in the different yam varieties .