This research porpose to determine the appropiate concentration of ethanol to obtain the highest antioxidant activity of cogon grass rhizome (Imperata cylindrica (Linn.) Beuv.) extract using ultrasonic wave. This research used a completely randomized design method with the treatment of concentration ethanol which consisted of six levels : 40, 50, 60,70, 80 and 90%. The whole treatment was repeated three times to obtain 18 units of the experiment. The data were analyzed by ANOVA, if the treatment showed the influenced then it continued by Duncan test. The result showed that the best treatment is using ethanol 70% with characteristic extract : yield was 14.13%, total phenolic was 129.57 mgGAE (Gallic Acid Equivalent)/g extract, total flavonoid was 90.91 mgQE (Quercetin Equivalent)/g extract and antioxidant activity was 56.03% with the IC50 value 0.098 mg/ml

The study aims to determine the effect substitution of modified purple sweet potato flour on the characteristics of waffle and to know the best substitution of modified purple sweet potato flour with pregelatinization. The study design used was randomized group design with the treatment substitution of modified purple sweet potato flour and wheat flour, which consists of 6 levels such as: 0% : 100%, 20% : 80%, 40% : 60%, 60% : 40%, 80% : 20%, 100% : 0%. The treatment was repeated 3 times to obtained 18 units of the experiment. The data were analysed by analysis variance and if the treatment had an effect on the variable then continued with Duncan test. The result showed substitution of modified purple sweet potato flour and wheat flour had a significant effect on the content of ash, crude fiber, antioksidan capacity, texture, criteria hedonic and skor of colour, texture  and taste. Substitution of modified purple sweet potato flour 100% had the best characteristics, with 41,84% water content, 1,94% ash content, 7,17% coarse fiber content, 81,65 (mg GAEAC/kg) antioksidan capacity, 1,64 N texture, criteria skor colour dark brown, texture soft, taste of purple sweet potato very strong  and criteria hedonic colour, aroma, texture, taste and overall acceptance were like.

This study aims to determine the effect of comparative of wheat and cowpea flour to characteristics of crackers andto knowing the composition to produce crackers with the best characteristics. The experimental design used was Completely Randomized Design with treatment factor that is the comparative treatment of cowpea flour with wheat which consist of 5 levels : 100%:0%, 95%:5%, 90%:10%, 85%:15%, and 80%:205. The treatment was repeated 3 times to obtain 15 units of experiment. The data obtained were analyzed by variance and if the treatment had an effect on the observed variable then continoued with Duncan test. Result of this study showed that comparation of wheat flour and cowpea flour very affected for protein content and coarse fiber content, affected water content, ash content, color, texture, and overall acepatance. Comparation of 80% wheat flour and 20% cowpea flour is the best characteristics of crackers with criteria 2.24% water contet, 2.62% ash content, 23.93% fat content, 10.70% protein content, 61.28% carbohydrate content, 6.61% crude fiber content, 0.44 power of broke, the color was liked, the aroma was neutral, the taste was liked and a little typical of cowpea, texture was crunchy and liked, and overall aceptance was liked. Keywords: Crackers, cowpea flour, wheat flour.

Daun alpukat mengandung komponen bioaktif yang tinggi sehingga dapat dimanfaatkan sebagai sumber antioksidan alami. Tujuan dari penelitian ini adalah mendapatkan metode pengeringan yang tepat sehingga menghasilkan ekstrak daun alpukat dengan aktivitas antioksidan yang tinggi. Daun alpukat baik yang muda maupun yang tua dikeringkan dengan tiga metode pengeringan yaitu dijemur dibawah sinar matahari, dikeringanginkan dalam ruangan, dan dikeringkan dengan oven. Kualitas daun kering kemudian dianalisis aktivitas antioksidan, kadar air, total fenol, total flavonoid, dan total tanin. Hasil penelitian menunjukkan bahwa daun tua yang dikeringkan dengan menggunakan oven pada suhu 40˚C selama 24 jam menghasilkan aktivitas penghambatan radikal bebas tertinggi yaitu 19,83% dengan kadar air 7,54%, total fenol 6,42 mg/100 g ekstrak, total flavonoid 12,07 mg/100 g ekstrak, dan total tanin 2,48 mg/100 g ekstrak. Kesimpulannya, metode pengeringan dapat memberikan dampak terhadap kadar senyawa bioaktif ekstrak daun alpukat dan aktivitas antioksidannya.Effect of Drying Methods on the Antioxidant Activity of Avocado LeavesAbstractAvocado leaves contain high bioactive components that may be used as a source of natural antioxidants. The purpose of this study was to obtain proper drying method to produce avocado leaf extract with high antioxidant activity. Avocado leaves, both young and old, were dried with three drying methods, which were dried in the sun, room, and oven. Quality of leaves was then measured for antioxidant activity, moisture, total phenol, total flavonoid, total tannins. The results showed that old leaves dried using an oven at 40˚C for 24 hours resulted in the highest radical scavenging activity of 19.83% with 7.54% moisture content, 6.42 mg/100 g extract of total phenol, 12.07 mg/100 g extract of total flavonoid, and 2.48 mg/100 g extract of total tannins. In conclusion, the drying methods might produced specific antioxidant activities.

The research aim to determine the effect of ratio purple sweet potato flour and soybean flour on characteristics functional flakes and determine the exact ratio of purple sweet potato flour and soybean flour which can produce functional flakes with the best characteristics. The Completed Randomized Design was used in this research consisting ratio of purple sweet potato flour and soybean flour including (P1) 90% : 10%, (P2) 80% : 20%, (P3) 70% : 30%, (P4) 60% : 40%, (P5) 50% : 50%. The data obtained were analyzed by variance and if the treatment had significant effect followed by Duncan Multiple Range Test (DMRT). The result showed that flakes with comparison of 70% purple sweet potato flour and 30% soybean flour is the best treatments with criteria moisture content of 3.05%, ash content of 2.09%, protein content of 17.04%, crude fiber 3.76%, anthocyanin total 21.07 mg/100g, antioxidant activity 39.55%, water absorption 165.66% and color is purple and like, aroma is like, texture is crispy and like, taste is like and overall acceptance is like.