Effect of Inoculum Size of Kefir Grain and Fermentation Temperature on Nut Milk Kefir

A study of the effect of inoculum size of kefir grain and fermentation temperature on nut milk kefir was conducted with the use of basic ingredients: raw almond, water and kefir grains. Factors of the experiment design (inoculum size of kefir grain 1, 3 and 5%; fermentation temperature: room temperature and 30 oC) was used to conduct formulation trials and analysis tests in duplicate. The responses collected involved pH, total soluble solid (oBrix), alcohol content, lactic acid content and microbiological analysis which included total plate count, microbe count and antibacterial properties of the almond milk kefir. The results has shown that the pH and the oBrix values dropped when increased in inoculum size of kefir grain in almond milk kefir with higher fermentation temperature (30 oC). Meanwhile, the alcohol content, lactic acid content and microbe count after fermentation has increased with the increased of kefir grain inoculum size and fermented with higher temperature (30 oC). Almond milk kefir with 5% of kefir grain fermented at 30 oC has the lowest pH which was 3.88 ± 0.06. It also has the highest alcohol content and lactic acid content which was 2.3 ± 0.3 and 0.387 ± 0.006. It also had a microbe count of 1.57 ± 0.06 x 107 which was the highest count when compared with other almond milk kefir with smaller inoculum size of kefir grain and fermentation temperature. All the almond milk kefir do not show any antibacterial properties to the bacteria E.coli and S.aureus. . Keywords: kefir grain, almond milk kefir, fermentation