Judul: Volatile Compounds Profiling and Markers Identification in Various Meat Broths Using SPME-GC-MS
Abstrak: Halal authentication for food products is critical worldwide, especially for muslim. Meat broth is one of the food products frequently adulterated with less expensive or non-halal ingredients. Halal authentication can be done using a DNA or protein-based approach, but this research aims to develop an authentication method that is easy, fast, and sensitive. Empirically, broth prepared from different type of meat has a different aroma. As a result, in this study, a volatilomics approach will be used to profile volatile compounds from various meat broths (chicken, pork, beef, goat, and duck) and to determine the typical marker compounds in each meat broth. The profile of volatile compounds was identified using the solid phase microextraction method combined with gas chromatography-mass spectrometry (SPME-GC-MS). Multivariate analysis was used to determine the differentiating compounds in meat broth: principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The volatile compounds identified in this study for chicken, pork, beef, goat, and duck broth (89, 79, 76, 78, and 99 compounds, respectively). The aldehyde group is the most volatile compound in various meat broths because it has a low odor threshold, making it easy to detect and significantly contributing to the distinct flavor of the food matrix. The results of PCA analysis with two principal components can explain 59.5% of the data variation and show a trend of grouping meat broth based on its volatile compounds. Furthermore, the OPLS-DA model analysis revealed that the profile separation of volatile compounds from meat broth was superior to PCA analysis, with a variance value (R2X = 0.79; R2Y = 0.94) and a predictive coefficient value (Q2 = 0.75). Validation of the OPLS-DA model by performing a permutation test and a CV-ANOVA test, which shows that the model is valid and acceptable. The marker compounds were selected based on two criteria: volatile compounds that were positively correlated and had a high VIP (variable importance in projection) value. The main marker compounds contained in pork broth are fatty acids. Fatty acids were detected in the broth because the predominant matrix of the broth was lipid and water. Overall, the marker compounds in pork broth were dodecanoic acid, n-decanoic acid, heptadecanal, 2-pentadecanone, eugenol , 2-tridecanone, and (E,E)-2,4-nonadienal. According to the findings of this study, the volatilomics approach successfully distinguished various meat broths, thus enabling the marker compounds to be used as a database for halal authentication of processed meat products.
Keyword: authentication, broth, discriminant analysis, halal, volatilomics

Judul: Systematic Review on Volatile Profile Compound and Its Application in Species Identification for Halal Authentication
Abstrak: Volatilomic is an emerging research area where its rapidness and accuracy in its diagnostic ability have been reported to be promising and also is economically favorable. Meat and meat-based food produces certain composition of volatile compounds which can be utilized in identification of its origin and consequently be used for food authentication. Systematic literature review on various publications was done to evaluate the use of volatiles in identification of meat-based food. This review focuses on the volatile profile compounds, various factors which could affect its production, its extraction and detection method, and its application in meat and meat-based food with a brief background discussing on the possibility on its utilization for halal authentication. The result shows that major component of volatile compounds associated with the aromas of meat are of from aldehydes, ketones and alcohols with each of type of meat having variation in its composition. There is no definite pattern. Most of these volatile compounds are the products of combination of Maillard reaction, Stecker degradation, or interaction of both, as well as thiamine degradation. Commonly used extraction method for meat samples is HS-SPME (Head Space-Solid Phase Microextraction) as it is solventless, having high sensitivity and practical. Main analysis method for detection of the metabolites volatile compounds is Gas Chromatography-Mass Spectrometry and is the most superior out of other method options. As for Halal authentication, there is a potential and possibility of utilizing volatile compound profile of meat species for such purpose but not enough evidence or scientific study to entirely rely on it alone. Therefore, require a further validation technique such as PCR. Further studies need to be conducted revolving utilization of meat volatile compound profiles for halal authentication.
Keyword: Volatile Compound Profile, Halal Authentication, Meat, Meat-Based Food

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf