PERUBAHAN SIFAT MIKROBIOLOGI DAN KIMIAWI RUSIP SELAMA FERMENTASI (Microbiological and Chemical Changes of Rusip during Fermentation)

Abstract

Rusip can be made both spontaneously and non-spontaneously. Starter is not added to spontaneous rusip, while to that of non-spontaneous, liquid starter is added in the form of a mixture of lactic acid bacteria including Streptococcus, Lactococcus and Leuconostoc as much as 2% (b/v). This research was aimed at investigating microbiological and chemical changes of rusip, both spontaneously and non-spontaneously. The treatment was repeated three times. The data obtained were then analyzed by applying student t-Test at the level of alpha 5%. The investigation conducted included the total lactic acid bacteria, total yeast, total microbes, pH, total acid, reducing sugar, and total volatile nitrogen (TVN). The findings show that microbiological and chemical characteristics of non-spontaneous rusip were better than those of non-spontaneous during 14-day fermentation. The criteria were the total lactic acid bacteria 12.37 log cfu/; total yeast 4,57 log cfu/g; total microbes 5.94 log cfu/; pH 5.69; total lactic acid 5.04%; reducing sugar 1.29%; TVN 27.57 mg N/100g, while the characteristics of spontaneous rusip include the total lactic acid bacteria 10.40 log cfu/g; total microbes 8.68 log cfu/g; total yeast 5.99 log cfu/g; pH 5.98; total acid lactate 3.12%; reducing sugar 3.63%, and TVN 44, 98 mg N/100g. Keywords: Rusip, fermentation, spontaneous, non-spontaneous ABSTRAK Rusip dapat dilakukan secara spontan dan tidak spontan. Pada rusip spontan tidak ditambahkan kultur, sedangkan pada rusip tidak spontan ada penambahan kultur cair campuran bakteri asam laktat yaitu Streptococcus, Lactococcus dan Leuconostoc sebanyak 2% (b/v). Penelitian ini bertujuan mengetahui perubahan sifat mikrobiologi dan kimiawi rusip baik spontan maupun tidak spontan. Perlakuan diulang sebanyak tiga kali. Data yang diperoleh kemudian dianalisis dengan menggunakan uji t student pada taraf alpha 5%. Pengamatan yang dilakukan meliputi total bakteri asam laktat, total kapang, total mikroba, pH, total asam, gula reduksi dan total volatile nitrogen (TVN). Hasil pengamatan menunjukkan bahwa sifat mikrobiologi dan kimiawi rusip tidak spontan lebih baik dibandingkan dengan rusip spontan selama 14 hari fermentasi. Adapun kriterianya yaitu total bakteri asam laktat 12,37 log cfu/g; total mikroba 5,94 log cfu/g; pH 5,69; total asam laktat 5,04%; kadar gula reduksi 1,29%; TVN 27,57 mg N/100g, sedangkan karakteristik rusip secara spontan yaitu total bakteri asam laktat 10,40 log cfu/g; total mikroba 8,68 log cfu/g; total kapang 5,99 log cfu/g; pH 5,98; total asam laktat 3,12 %; kadar gula reduksi 3,63% dan TVN 44, 98 mg N/100g. Kata kunci: Rusip, fermentasi, spontan, tidak spontan