EFFECT OF PURE STARTER CULTURES ON QUALITY OF FERMENTED PORK (NHAM) PRODUCTION IN THE SUMMER TIME

Abstract

Two sources of Nham (fermented pork) sold in Chiang Mai were bacterilogically and chemically studied. The criteria used to selected lactic acid bacteria from these products for preparation of starter cultures are : fast growing within 24 hours, good production of lactic acid and capable of reducing nitrate. Thirteen isolates were obtained and used in combination of 4-8 isolates as Nham starter cultures in four treatments of Nham produced in summer. Results from chemical, bacterialogical and sensory analysis of these treatments compared with control showed that the colour, flavous, taste, texture and overall characteristics of Nham procuced from starter cultures com parable to that of control Nham. The nitrate, nitrite and nitrosamine contents of these Nham were much below the standard limits. The pH content decreased and the amount of lactic acid increased very rapidly even on the first day of production when stored at 25 degree celcius. Salmonella were detectable in three treatments at the beginning of production. It should be born in mind not to consume Nham when the pH is higher than 4.3. Row materials for preparing Nham must be in good condition so as to the quality control in every step must be taken into account throughout processing. Nham produced from starter cuttures were sensorial evaluated and well accepted.