THE POTENCY OF KROKOT (Portulaca oleracea) AS FUNCTIONAL FOOD INGREDIENTS

Daisy Irawan, Purwiyatno Hariyadi, Hanny Wijaya

(Indoneisan Food and Nutrition Progress 2003/Vol 10/ No 1)

Abstract

Indonesia has many auxiliary plants that may have nutritional and or environmental benefits, so that it may increase the yield of the main crops. Krokot (Portulaca oleracea), one of the auxiliary plants, was traditionally consumed in many parts of the world for its delicacy and medicinal benefits. Our research indicated that krokot has high potency to improve the health status of the community. It has 5.4 mg/100 g of b-carotene, 22.2 mg/IOO g ofvitamin C, and significant amount of folic acid (0.2 mg/100 g). Krokot was traditionally used to treat scurvy, and various of infectious and skin diseases. Literature review revealed that krokot has essential fatty acid, it also has antimutagenic, and antimicrobial activity. Unfortunately, krokot is approaching extinction both physically and ethnobotanically because they are considered as useless plants or even weed. Our survey on 103 agricultural university students revealed that only 24% ofthe respondents knew krokot. Krokot is especially difficult to find in intensively cultivated area. Along with other indigenous vegetables, Portulaca oleracea is almost never served again in Indonesian cllisine. Utilization krokot as functional food ingredients might helps to conserve the plant as well as encouraging sustainable agriculture.

IDENTIFICATION OF POTENT ODORANTS IN DIFFERENT CULTIVARS OF SNAKE FRUIT [SALACCA ZALACCA (GAERT.) VOSS] USING GAS CHROMATOGRAPHY−OLFACTOMETRY

Wijaya CH, Ulrich D, Lestari R, Schippel K, Ebert G

(J. Agric. Food Chem. 2005, 53 (5):1637–1641)

 

Abstract

Three cultivars of snake fruits, Pondoh Hitam, Pondoh Super, and Gading, were freshly extracted using liquid−liquid extraction. The aroma compounds of the three samples were analyzed by GC-MS and GC−olfactometry using the nasal impact frequency (NIF) method. A total of 24 odor-active compounds were associated with the aroma of snake fruit. Methyl 3-methylpentanoate was regarded as the character impact odorant of typical snake fruit aroma. 2-Methylbutanoic acid, 3-methylpentanoic acid, and an unknown odorant with very high intensity were found to be responsible for the snake fruit’s sweaty odor. Other odorants including methyl 3-methyl-2-butenoate (overripe fruity, ethereal), methyl 3-methyl-2-pentenoate (ethereal, strong green, woody), and 2,5-dimethyl-4-hydroxy-3[2]-furanone (caramel, sweet, cotton candy-like) contribute to the overall aroma of snake fruit. Methyl dihydrojasmonate and isoeugenol, which also have odor impact, were identified for the first time as snake fruit volatiles. The main differences between the aroma of Pondoh and Gading cultivars could be attributed to the olfactory attributes (metallic, chemical, rubbery, strong green, and woody), which were perceived by most of the panelists in the Pondoh samples but were not detected in the Gading samples. This work is a prerequisite for effective selection of salak genotypes with optimal aroma profiles for high consumer acceptance.

ETHNOBOTANICAL STUDY AND NUTRIENT POTENCY OF LOCAL TRADITIONAL VEGETABLES IN CENTRAL KALIMANTAN

Irawan D, Wijaya CH, Limin SH, Hashidoko Y, Osaki M, Kulu IP
(TROPICS 2006/Vol 15/No 4)

Abstract

The Dayak people in Central Kalimantan, traditionally consumed local vegetable, either collected from the wild or traditionally cultivated. Unfortunately, many of the traditional vegetables are approaching extinction, even in their local market. This research is intended to conserve the traditional vegetable by collecting nutritional data and cultural information about the vegetable. Nineteen traditional Dayak vegetables were observed in local markets and in wild areas. Taxonomic identification revealed that the vegetables were Passiflora foetida L. (kemot), Diplazium esculentum (Retz). SW. (bajey fern), Spondias pinnata (L.f.) Kurtz (kedondong leaves), Neptunia oleracea Lour (malu-malu leaves), Manihot esculenta Crantz (cassava leaves). Vigna unguiculata (L.) Walp. (talak leaves), Etlingera elatiar (Jack) R.M. Smith (potok shoots, red and green cultivar), Calamus sp. (rotan shoots), Nauclea sp. (Taya leaves), Momordica charantia L. (paria leaves), Gymnopetalum cochinense Kurz (kanjat), Solanum torvum Swartz. (segau fruit), Colocasia esculenta (L.) Schott (sulur keladi shoots), Stenochlaena palutris (Burm.)Bedd. (kalakai leaves; red and white cultivar), lotus shoots (pucuk teratai), and Cnesmone javanica Blume (lampinak leaves).

Nutrient analysis revealed that red kalakai (wild fern) has the potential nutrient value. It has a high amount of Fe (41.53 ppm), Cu (4.52 ppm), vitamin C (15.41 mg/100g), protein (2.36%), β-carotene (66.99 ppm), and folic acid (11.30 ppm). Other iron-rich vegetables were sulur keladi (49.25 ppm) and bajey (44.6 ppm). While other vitamin C-rich vegetables were paria leaves (18.34 mg/100 g wb), and bajaj fern (22.05 mg/100g w.b). Sulur keladi and bajey were also rich in folic acid. They had 16 and 6.3 ppm of folic acid respectively. The β-carotene content in bajey was 74.04 ppm while taya was 77.41 ppm.

Physico-Chemical Properties, Sensory Characteristics and Glycemic Index of Tidal Peat-Swamp Rice Grown in South Kalimantan

 

Wijaya CH, Bernard, Purnomo E, Hashidoko Y

 (ASEAN Food Journal 2007, 14 (1): 37-43)

Abstract

“Panjang” rice is an ethnic rice strain found in a tidal peat swamp Aluh-Aluh, South Kalimantan. A series of analyses on its sensory and physico-chemical properties included proximates, mineral content, amylose content, starch gelatinization, grain size and color were carried out to compare its quality to that of the commercial wet-land rice. Its glycemic index was also measured to explore its low glycemic potency. “Panjang” rice was classified as a medium sized grain (5.50 mm length) with high amylose content of 31.1% (db), gelatinized at 77.3oC with gelatinization peak at 97.5oC and maximum viscosity at 637.5 BU. There were significant differences between “Panjang” rice and IR 42 in ash, fat, protein, carbohydrate, and mineral (Na, S and P) contents, amylose content as well as grain brightness. No significant (p<0.05) difference was observed in sensory properties between ”Panjang” and”“IR 42” cooked rice, except that no bitter taste was sensed in “Panjang” rice . Based on its glycemic index, which was as low as 46.8, “panjang” rice can be classified as low glycemic index rice.

ROLE OF BACTERIA IN TEMPE BITTER TASTE FORMATION: MICROBIOLOGICAL AND MOLECULAR BIOLOGICAL ANALYSIS BASED ON 16S rRNA GENE

Tati Barus, Antonius Suwanto, Aris Tri Wahyudi, Hanny Wijaya

(Microbiology Indonesia/Vol 2/No 1/2008)

Abstract

 

Tempe is traditional Indonesian food. It has a variety of tastes, sometimes with a hint of bitterness, which may differ in intensity. The cause of bitterness in tempe has never been reported previously. In this study, the aim is to identify whether bacteria play a role in the formation of bitter tastes in tempe. Sensory tests were carried out in order to determine the scores of bitter-taste-intensity in tempe. The sensory test on EMP, WJB, CLR, DRG, and MLB tempe shows that EMP tempe has the highest score (2.3) and WJB has the lowest (1.3). It is revealed that the processing method has no impact on the formation of the bitter taste in tempe. Plating analysis, showed that EMP soaking water contained a higher number of Enterobacteria group bacteria, approximately 103-104 CFU ml-1 and spore-forming bacteria groups, 102 CFU ml-1, compared to WJB. Similarly, other bacteria groups in fresh EMP tempe was 102 CFU g-1 higher than those in fresh WJB tempe. Based on sequencing the16S rRNA gene, the dominant bacteria on PCA media in EMP tempe are Acetobacter indonesiensis, Klebsiella pneumoniae, Bacillus subtilis, and Flavobacterium sp. On the other hand those in WJB tempe were Klebsiella sp., Brevundimonas sp., Bacillus sp., Pseudomonas putida, and Acinetobacter sp. Bacillus, a group of proteolytic bacteria was found 105 CFU m-1 higher in the soaking water of EMP compared to WJB. Nevertheless, the types and numbers of fungi were not significantly different between tempe types. Accordingly, it is concluded that the difference in the number and the types of bacteria involved in the tempe production process leads to the difference in the bitter taste intensity in both EMP and WJB tempe.