G N Oktaningrum’s scientific contributions

Spontaneous and ragi fermentations are the most common methods in producing traditional fermented foods in Indonesia. The present work aimed to compare the impacts of spontaneous and ragi fermentations on cereal flour properties. Three kinds of cereal, namely whole sorghum, waxy coix, and white maize were processed into flours through spontaneous fermentation, ragi fermentation, and without fermentation (control). Fermentation methods were adopted from the Indonesian traditional processing methods. Cereal grains were immersed for 72 h in distilled water (1:2 w/v) for spontaneous fermentation, and in 1% ragi tapai solution (1:2 w/v) for ragi fermentation. Meanwhile, native flour (without fermentation) was produced by grounding and sieving the cereal grains. Results showed that both fermentation techniques significantly altered the physical properties of cereal flours, as indicated by the increase in lightness index and decrease in water-binding capacity and viscosity. However, cereal flours’ chemical and functional properties remain unchanged during fermentation, except for lipid and amylose. Spontaneous fermentation significantly resulted in the lowest lipid content of cereal flours, while ragi fermentation resulted in the lowest amylose content of cereal flours. Sorghum flour generally showed better nutritional properties among the examined cereal flours, especially lipid, protein, and dietary fibre. Meanwhile, waxy coix and white maize flours had the highest folate.

KUB chicken is the superior village chicken of the Agricultural Research and Development Agency with egg production reaching 180 eggs/ year. With this advantage, KUB chickens have been cultivated and developed since 2016. In addition to producing quite a lot of eggs, KUB chickens also have delicious meat to eat. One of the most popular processed chicken meat especially for children is chicken nuggets. KUB chicken nuggets were tested for sensory testing including color, texture, aroma and taste for several panelists. The experimental design used in this study was a completely randomized design. The sensory test results showed that KUB chicken nuggets were preferred compared to commercial chicken nuggets. Keywords: KUB Chicken, Nuggets, Sensory quality

In the vegetable preservation process, baking treatment is commonly applied to enhance the end-product quality. This study was carried out to observe baking influences as an alternative pretreatment toward dried beetroot quality. A completely randomized design with different baking times (0, 15, 30, and 45 min) at 200°C was adjusted on beetroot before sliced and dried (50±5°C, 24 h). The result showed that baking treatments significantly affected the whole quality attributes of dried beetroot. There was an increase in anthocyanin, total phenolic, total sugar, and pigment intensity of dried beetroots with the more prolonged baking treatment. Dried beetroot prepared by 45 min baking treatment contained total anthocyanin 109.57 mg/100 g, total phenolic 8.66 mg/100 g, and total sugar 5.13%. Baking treatment for 45 min also resulted in intense color development of redness (a*) and yellowness (b*), although the lightness (L*) reduced due to dark color formation.

The Highland of Magelang Regency has a strategic role as a vegetable production center in Central Java. Farmers in the highlands of Magelang cultivate various types of vegetables. Since highland vegetable farming hugely depends on rainfall as a primary water source, climate change remarkably affects farming. Vegetable farmers often encounter problems due to climate changes in drought and highly intense rainfall, which caused crop damage. Since specific studies on vegetable farmers’ adaptation strategies to cope with climate changes and their economic effects are still limited, this research aimed to study the phenomenon. The observation was performed by interviewing all members (20 farmers) of the Mutiara Organic farmers group in Sumberejo Village, Ngablak Sub-Regency, Magelang Regency, conducting field observation and soil analysis in September-November 2018. The results showed that farmers developed several adaptation strategies to deal with climate change, namely applying multiple cropping systems, developing organic agriculture, growing vegetables under plastic shelters, and expanding a vegetable nursery as an alternative source of income. Farmers cultivated extra crops in the wet season due to abundant water availability. Organic vegetable farming, which began in 2013, from the higher value of the benefit-cost ratio, was more profitable than non-organic farming. Besides, organic farming’s land quality was also better based on organic carbon (C-organic), Nitrogen (N), Cation Exchange Capacity (CEC), and other nutrients. Therefore this study recommended to develop organic vegetable farming on a broader scale and seriously support farmers’ vegetable nursery business, since it was profitable, contributed significant income for farmers, and strategic for vegetable farming industries development.

Cassava leaves are nutritious vegetable, but often regarded as an inferior commodity. One of the efforts increasing in the benefit of cassava leaves is through processing it into snack. In order to support the food diversification program and to reduce the dependence on imported commodities, the development of cassava leaves snack could be accompanied by optimizing the use of local materials to minimize the use of wheat flour. The aim of this assessment was to learn the effects of cassava and corn flour substitution on the physicochemical characteristics of cassava-leaves snack. The substitution of local flour (cassava and corn) on the snack production was carried on three levels at 15, 30, and 45%. A control treatment was using 100% wheat flour. The results showed that cassava and corn flour were potential to substitute wheat flour for making cassava-leaves snack. The substitution of cassava and corn flour as much as 45% was able to produce crispy products with a brighter color. The substitution of corn flour was resulting in snacks with the lower content of lipid than the other substitution snacks.

Tomato as an agricultural product is extremely perishable. Coatings of tomatoes with edible starch extend quality and storage life of the fruits. Incorporation of citric acid as antimicrobial agent in the edible starch coatings is expected to preserve the quality of tomatoes during storage. The aim of this study was to verify the effectiveness of citric acid incorporated in cassava starch coating to preserve quality of tomatoes. The edible coatings formula consisted of cassava starch solutions (1; 2; 3%), citric acid (0.5; 1.0%) and glycerol (10%). Tomatoes were dipped to the coating solution for 10 seconds, then air-dried and stored at room temperature during 18 days. All the treatments were carried out in triplicates. Experimental data were analyzed using One Way ANOVA. The results showed that coating treatments did not affect the weight loss, moisture content, color characteristic, carotene and vitamin C content on Martha tomatoes. The low concentration of starch coating on Martha tomatoes are indicated to be the reason why there was no significant difference between coated and coated tomatoes for some parameters. However, incorporating citric acid in cassava starch-based coatings could prevent tomato fruits from firmness reduction and spoilage during storage.