Barley has been the basic raw material for brewing for both barley and non-barleyrnproducing countries. Its malt is known to be rich in protein, high diastatic power and highrnlevel of maltose producing ï¿½ï¿½ âˆ’amylase, a key enzyme in breaking down malt starch intornfermentable sugars ensuring efficient Saccharification than other cereals making it brewersâ€™rnchoice however, the skyrocketing price of barley calls for an alternative brewing techniquernforcing to propose an increment of unmalted to malt ratio with some modification in mashingrnmethod but this method alone have lots of challenge due to dilution of malt enzyme there forrnaddition of external enzyme with an extension temperature program conversion is used. Thernextension of time was used to obtain with suitable high wort true ferment ability andrnsufficient protein break down. Unmalted and malted barley milled separately and mixedrnbased design ratio( 20 to 100%) then mashed using EBC method 4.5.1 with the addition of 0rnto 1% (Neuterase, Term-amyl SC, and Ultra-flow max). Design software response surfacernmethodology central composite design was used to see the relationship dependent andrnindependent variables. The result found was 17.3% viscosity decreased, 11.9 % incrementrnextract recovery level, 53.5% increment for free amino nitrogen content of wort produced inrnmashing of 100% raw barley with 1% vol/grist wt. of Term amyl sc, Neuterase, ultra-flowrnmax enzyme ,the result found was improve filtration rate ,brewing yield ,speed ofrnfermentation and fermentation cycle. The optimum result that we found based on sensoryrnanalysis was 60/40 unmalted to malted ratio with 0.5% ultra-flow max 0.5% Term amyl scrnand 0.5% Neuterase Vol/grist wt. Therefor addition of Term-amyl sc, Neuterase, ultra-flowrnmax plus modification mashing method could be one solution for increasing unmalted tornmalted ratio.rnKey words: Exogenous and endogenous enzyme, degree of attenuation, viscosity, responsernsurface methodology