Judul: Development of Miang Salad, A Pickled Tea Leaves Product of Thailand
Abstrak: Miang is pickled tea leaves (Camellia sinensis var. Assamica) from northern Thailand. While its taste is not well accepted, it has high antioxidant activity. Therefore, this research was aimed to develop miang salad that meets consumer’s preference. In developing this product, three studies were done. Firstly, the quality of miang was investigated. The pH of miang was 4.26±0.01, while the total polyphenol content (TPC) and DPPH radical scavenging activity were 15.14±0.37% (w/w dry basis) and 113,058.54±5,643.17 μmol Trolox/100 g dry basis, respectively. For microbiological properties, the total viable count and yeast and mold count were 2.8x105 CFU/g and 5.0x105 CFU/g. The coliform bacteria was less than 3.0 MPN/g. Secondly, suitable formulation for miang salad was studied. There were 6 formulas developed by using mixture design technique. Three miang salad contents were varied: miang (50-80%), pickled ginger (10-40%), and pickled garlic (10-40%). Sensory evaluation was conducted by using 30 untrained panelists (Mae Fah Luang University students) to evaluate the color, odor, sweetness, sourness, and overall liking of miang salad. The result showed that the best formula consisted of 50% miang, 10% pickled ginger, and 40% pickled garlic had the highest overall liking score of 6.30±1.80. Miang salad from the best formula was pasteurized at 70 oC and 80 oC for 10, 15, and 20 minutes. Pasteurization reduced the number of microbes down to <2.5x101 CFU/g (total viable) and <1.0x100 CFU/g (yeast and mold). However, heat treatment reduced the product’s lightness and antioxidant activity. Higher temperature and longer holding time produced worse effect. At 70 oC, TPC and DPPH radical scavenging activity decreased by 2.31-6.92% and 5.33-16.67%, while at 80 oC decreased by 16.14-22.22% and 41.27-49.66%, respectively. In conclusion, miang salad pasteurized at 70 oC 10 minutes was the chosen product due to its highest overall liking score and considering its microbial count, antioxidant activity, and color.
Keyword: Consumer preference, miang salad, pasteurization

Judul: Canning of Ready to Eat Mandai in Retort  Pouch
Abstrak: Meningkatnya preferensi konsumen terhadap pilihan makanan sehat telah mendorong perkembangan makanan fermentasi tradisional di pasar modern. Mandai adalah makanan fermentasi tradisional dari Kalimantan yang dibuat menggunakan bahan utama kulit bagian dalam (mesokarp) buah cempedak (Arthocarphus champeden). Mandai merupakan salah satu makanan tradisional favorit di Kalimantan, namun belum banyak dikembangkan teknologi pengolahannya. Aplikasi teknologi pengalengan dapat menjadi solusi untuk meningkatkan mutu dan keamanan mandai. Penelitian ini bertujuan untuk menentukan standardisasi formula mandai siap saji (RTE) sebelum pengalengan dan mempelajari proses pengalengan mandai RTE dengan proses pasteurisasi. Hasil penelitian menunjukan formula standar mandai RTE dihasilkan dengan proses fermentasi selama 15 hari menggunakan larutan garam non-iodium 10%. Proses pengalengan mandai RTE dalam kemasan retort pouch dapat dilakukan pada suhu 85oC selama 10 menit. Proses tersebut dapat memenuhi target pengurangan >6D untuk Lactobacillus spp. Semakin tinggi waktu pemasakan awal yang digunakan pada proses pengalengan mandai menyebabkan meningkatnya nilai pasteurisasi (P85) dan browning index (BI), sedangkan profil tekstur, kandungan protein dan kadar air menurun. Kandungan karbohidrat, lemak, abu, pH dan Aw tidak berubah signifikan. Analisis mutu mikrobiologi menunjukan tidak ditemukannya pertumbuhan E. coli, Salmonella spp., Lactobacillus spp., kapang dan khamir pada seluruh sampel setelah proses pengalengan, sedangkan total mikroba anaerob masih dapat ditemukan dengan populasi yang semakin menurun yaitu dari 2,79 menjadi 2,53, 2,28 dan 1,77 log CFU/g setelah pengalengan dengan variasi waktu pemasakan awal 7,50, 11,25 dan 15,00 menit secara berturut-turut. Hasil uji sensori menunjukan pengalengan juga dapat meningkatkan keberterimaan mandai RTE oleh panelis dibandingkan dengan kontrol, The increase of consumer preference for healthy food choices has encouraged the development of traditional fermented foods in the modern market. Mandai is traditional fermented food from Kalimantan that is made from the inner-skin (mesocarp) of cempedak fruit (Artocarpus champeden) as the main ingredient. Mandai is one of the favorite tradisional food in Kalimantan, but its processing technology is underexplored. The application of canning process provides an alternative solution to improve the quality and safety of mandai. This research aims to determine the standardization of the the ready-to-eat (RTE) mandai formula before canning process and to study the canning of the RTE mandai using thermal pasteurization. The result shows that the standardization of RTE mandai formulation is produced by 15-day fermentation process in 10% non-iodized salt solution. The canning process of RTE mandai can be performed using thermal pasteurization at 85oC for 10 min. This process is sufficient to achieve for > 6 log reduction of Lactobacillus spp. The increase of the pre-canning cooking time affected on the increase of the pasteurization value (P85) and browning index (BI), whereas the texture profile, protein and moisture content decreased. The contents of carbohydrate, fat, ash, pH and Aw did not significantly change. The microbiological quality shows that no growth of E. coli, Salmonella spp., Lactobacillus spp., yeasts and molds were found in all of the samples after the canning process. Whereas, the anaerobic microbial total was not completely inactivated by pasteurization process. It decreased from 2.79 to 2.53, 2.28, and 1.77 log CFU/g on different initial cooking time (7.50, 11.25, 15.00 min, respectively). The application of canning process on RTE mandai
Keyword: acid food, ready to eat food, retort pouch, cempedak, Arthocarphus champeden

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular