Quality of Peanut (Arachis hypogeae L.) Kefir with Variation in Ragi Starter Concentration and Long Fermentation

One of the fermented milk products, namely kefir, is increasingly popular because it has many health benefits. Peanut juice has a high enough protein content that it can be used as a substitute for animal milk. The purpose of this study was to determine the quality of peanut kefir with variations in the concentration of ragi tape inoculum and fermentation time. This research method used 3 variations in the concentration of tape yeast (1, 2 and 4%) and long fermentation time (24, 48 and 72 hours). The results showed that the highest total LAB was in 4% ragi tape inoculum with a fermentation time of 24 hours (4.4x108 cells/mL) and the lowest was in 4% tape yeast inoculum with a fermentation time of 72 hours (9.8x107 cells/mL) and total yeast between 1x104 cells/mL - 3x105 cells/mL) and alcohol produced <1%. Total acid obtained between 6% - 17.6%. The increase in total acid is proportional to the decrease in pH. The pH of the peanut kefir medium was between 3.44 - 4.12. Peanut kefir with tape yeast inoculum meets the standard requirements for fermented milk and can replace milk kefir.

Biotechnological starter potential for cocoa fermentation from cabruca systems / Potencial biotecnológico de leveduras starter na fermentação do cacau de sistema cabruca

Cocoa is a fruit of great economic importance, being the main raw material in the manufacture of chocolate. Among the stages of pre-processing, the main and most important is the spontaneous fermentation of the cocoa pulp by microorganisms, especially the yeasts, which initiate the process and contribute to the death of the germ of the seed, releasing compounds that directly influence the quality of the final product (flavor and aroma). Poorly fermented almonds confer bitter and astringent taste on chocolate, so it is advantageous to select autochthonous yeasts with better performance in the fermentation (producing enzymes of interest in the process) to be used as inoculum starter when added in the spontaneous fermentation, where they can accelerate the fermentation and contribute to raising the quality of the product. Therefore, the objective of this work was to qualitatively determine the production of enzymes of biotechnological interest by yeasts for the fermentation of cocoa through the cup plate method, in order to select a candidate yeast inoculum and use molecular typing technique to evaluate the diversity. Many promising yeasts were identified for use as inoculum among the diverse yeast groups found.

Effect of a Multistarter Yeast Inoculum on Ethanol Reduction and Population Dynamics in Wine Fermentation

Microbiological strategies are currently being considered as methods for reducing the ethanol content of wine. Fermentations started with a multistarter of three non-Saccharomyces yeasts (Metschnikowia pulcherrima (Mp), Torulaspora delbrueckii (Td) and Zygosaccharomyces bailii (Zb)) at different inoculum concentrations. S. cerevisiae (Sc) was inoculated into fermentations at 0 h (coinoculation), 48 h or 72 h (sequential fermentations). The microbial populations were analyzed by a culture-dependent approach (Wallerstein Laboratory Nutrient (WLN) culture medium) and a culture-independent method (PMA-qPCR). The results showed that among these three non-Saccharomyces yeasts, Td became the dominant non-Saccharomyces yeast in all fermentations, and Mp was the minority yeast. Sc was able to grow in all fermentations where it was involved, being the dominant yeast at the end of fermentation. We obtained a significant ethanol reduction of 0.48 to 0.77% (v/v) in sequential fermentations, with increased concentrations of lactic and acetic acids. The highest reduction was achieved when the inoculum concentration of non-Saccharomyces yeast was 10 times higher (107 cells/mL) than that of S. cerevisiae. However, this reduction was lower than that obtained when these strains were used as single non-Saccharomyces species in the starter, indicating that interactions between them affected their performance. Therefore, more combinations of yeast species should be tested to achieve greater ethanol reductions.

KAJIAN KONSENTRASI INOKULUM RAGI TERHADAP SIFAT KIMIA DAN BAKTERI ASAM LAKTAT TEMPE KACANG GUDE (Cajanus cajan, L) (Studi on Chemical Properties Yeast Inoculum Concentration and Lactid Acid Bacteria of Pigeonpea Tempeh)

ABSTRACTGenerally, tempeh is made from soybean, but low production of soybean in Indonesia bringing ongovernment have to import its. Soybean import 70% approximated from United State constitutetransgenic soybean which apprehensived have negative effect for health. Indonesia has so manylocal legume such as pigeon pea (Cajanus cajan (L.) Millsp.). That could be used as soy beansubstitute as raw material of tempeh. This study aimed to determine the effect of inoculumconcentration pigeonpea beans right to quality and chemical properties of lactid acid bacteriatempeh produced during the fermentation proces. It can be concluded that the inoculumconcentration of 2,50 g/kg of material, can increase levels of the amino nitrogen of 1,582 %, andcan inhibit the growth of lactid acid bacteria. It is also recommended for further research conducedon the long soaking, soaking place, and fermentation time is right to improve the quality ofpigeonpea beans tempeh produced.Keywords : Concentration of the inoculum, lactid acid bacteria, and tempeh pigeonpea

PENINGKATAN KUALITAS BIJI KAKAO (Theobroma cacao L) MELALUI FERMENTASI MENGGUNAKAN Lactobacillus sp. dan Pichia kudriavzevii

The Improvement of Cacao Beans Quality through Fermentation by Using Lactobacillus sp. and Pichia kudriavzeviiABSTRACTIndonesia is one of the main cacao producers in the world. Indonesian cacao product is, however, relatively of low quality. Quality improvement of cacao beans is thus needed to increase added value of the product through such method as fermentation using bacteria and yeast. This study was conducted using four fermentation treatments, namely F1 (spontaneous fermentation without the addition of inoculum), F2 (addition of lactic acid bacteria inoculum), F3 (addition of yeast inoculum), F4 (addition of mixed lactic acid bacteria and yeast inoculum). The fermentation was carried out for 5 days. The parameters measured were the microbial cell number, pH, ethanol, total reducing sugar, and total acid concentration, as well as cacao seed quality. Results showed that, compared to the other treatments, the F4 treatment gave the best result, namely 83% of the cacao seeds being fermented, 2% non-fermented, 14% unfermented, 1% moldy, and 2% germinated. The liquid produced during the fermentation contained the highest reducing sugar of 123.38 mg·mL-1, the highest total acid of 24.42 mg·mL-1, and 3.57% ethanol.Keywords: cacao beans, fermentation, lactic acid bacteria, starter, yeast ABSTRAKIndonesia adalah salah satu penghasil kakao utama di dunia. Namun berdasarkan mutu, produk kakao Indonesia masih relatif tergolong rendah. Peningkatan kualitas biji kakao diperlukan untuk memberikan nilai tambah pada produk melalui metode seperti fermentasi menggunakan bakteri dan khamir. Penelitian ini dilakukan dengan empat perlakuan fermentasi yaitu F1 (fermentasi secara spontan tanpa penambahan inokulum), F2 (dengan penambahan inokulum bakteri asam laktat (BAL)), F3 (dengan penambahan inokulum khamir), F4 (dengan penambahan inokulum campuran bakteri asam laktat dan khamir). Fermentasi dilakukan selama 5 hari, dan parameter yang diukur selama fermentasi adalah jumlah mikroba, pH, kadar etanol, gula pereduksi, total asam serta kualitas biji. Hasil menunjukkan bahwa, dibandingkan perlakuan lainnya, perlakuan F4 memberikan hasil terbaik yaitu 83% biji terfermentasi, 2% tidak terfermentasi, 14% terfermentasi sebagian, 1% berjamur, dan 2% berkecambah. Cairan fermentasi tersebut mengandung gula reduksi yang paling tinggi 123,38 mg·mL-1, total asam tertinggi 24,42 mg·mL-1, dan kadar etanol mencapai 3,57%.Kata Kunci: bakteri asam laktat (BAL), biji kakao, fermentasi, khamir, starter

Preparation and Antioxidant Activity of Purple Potato Wine

Purple potatoes were used as raw material to study the purple potato wine production process and antioxidant activity. This paper analyzed different fermentation time, fermentation temperature, yeast inoculum, initial pH, the initial sugar content on alcohol and anthocyanin contents of purple potato wine by single factor experiments and response surface methodology(RSM). The results showed that the optimum fermentation conditions of purple potato wine were as follows: fermentation temperature was 26oC, yeast inoculum was 0.15%, fermentation time was 7 d, initial pH was 3.0 and initial sugar content was 11 %. Under these conditions the alcohol and anthocyanin contents of purple potato wine could reach 10.55%/Vol and 6.42 μg/mL, respectively. The purple potato wine was purple, bright in colour, pleasant fragrance and pure taste. Prepared purple potato wine had the ability of reducing Fe3+ and scavenging superoxide anion radicals, which meant that purple potato wine had certain antioxidant activity.