Penggunaan spektroskopi fluoresensi yang nondestruktif bidang pertanian semakin intensif dilakukan khususnya untuk evaluasi produk pertanian. Sortasi dan grading Tandan Buah Segar (TBS) Kelapa Sawit sebelum memasuki proses produksi Crude Palm Oil sangat penting untuk memenuhi standar produksi dan ekspor. Sistem sortasi dan grading elektronik dibutuhkan untuk mengantikan metode sortasi manual mengandalkan penglihatan dan pengalaman. Pada penelitian ini probe optik yang terdiri dari laser dioda 640 nm dan dua fotodioda inframerah dalam konfigurasi triangulasi digunakan untuk mengevaluasi tingkat kematangan TBS kelapa sawit dan hubungannya dengan kekerasan buah dan tegangan fotodioda. Sampel terdiri dari 23 TBS Tenera. Buah kelapa sawit pada setiap TBS disinari laser pada tiga bagian yaitu pangkal, tengah dan ujung, setiap bagian terdiri dari tiga buah kelapa sawit. Tegangan keluaran dari kedua fotodioda dijumlahkan dan diperkuat oleh rangkaian multiboard komersial. Setelah tegangan diperoleh, ke-9 buah kelapa sawit dilepaskan dari TBS, tingkat kekerasan buah diukur mengunakan penetrometer. Hasil penelitian menunjukkan bahwa tingkat kematangan TBS mempunyai korelasi linier terhadap kekerasan buah dengan kekerasan yang tertinggi pada buah mentah sebesar 9,39 kg/cm2 dan terendah pada buah terlalu matang sebesar 5,64 kg/cm2. Nilai tegangan rata-rata terkecil pada buah mentah dan tertinggi pada buah matang kemudian turun pada buah lewat matang. Hasil K-means clustering menunjukkan pengelompokan 4 tingkat kematangan berdasarkan nilai kekerasan dan tegangan yaitu F0, F1, F2, dan F3. Applications of nondestructive fluorescence spectroscopy in agriculture have been intensively carried out especially to evaluate agriculture products. Sorting and grading oil palm fresh fruit bunches (FFB) before Crude Palm Oil milling processes are important tasks to meet the production and export standards. Electronic systems for sorting and grading of FFBs are needed to replace manual sorting method which depends on human vision and experience. In this study, an optical probe consisted of a 635 nm diode laser and two photodiodes was used to evaluate the ripeness level of oil palm FFB and its relation to both the fruitlet firmness and resulted photodiode voltages. Laser was directed to each of nine fruitlets of each FFB from three parts; basil, equatorial, and apical. Output voltages from each photodiode were summed and amplified by a commercially multi-board circuit. Then their firmness levels were obtained using a penetrometer. The results show that there is a linear correlation between the firmness levels and the FFB ripeness levels. The firmness values ranges from 9.39 kg/cm2 for unripe FFB and 5.64 kg/cm2 for overripe FFB. The highest voltage is obtained for ripe FFB and less for unripe and overripe FFB. K-means clustering results indicate that the overall ripeness levels are grouped into 4 levels of ripeness, namely F0, F1, F2 and F3 based on the values of hardness and the voltage of each sample.               Keywords: Fluorescence Spectroscopy, Oil Palm, Fresh Fruit Bunch, Firmness, Optical Probe

Tingkat Kematangan Tandan Buah Segar (TBS) kelapa Sawit merupakan faktor penentu kualitas crude palm oil (CPO) yang dihasilkan pabrik kelapa sawit. Metode penyortiran TBS setelah panen atau sebelum memasuki proses perebusan pada umumnya dilakukan secara manual mengandalkan penglihatan dan pengalaman. Metode ini rentan kesalahan dan bersifat subyektif. Metode pencitraan berkembang sangat cepat karena kemajuan dalam bidang komputer dan teknik pengolahan citra, khususnya untuk sistem sortasi dan grading. Penelitian ini mengunakan metode pencitraan fluoresensi yang diinduksi laser untuk mengakses dan mengklasifikasi tingkat kematangan TBS kelapa sawit. Hubungan antara tingkat keabuan dan tingkat kekerasan buah TBS dianalisa. Sampel terdiri dari 27 TBS kelapa sawit varietas Tenera. Tingkat kematangan dikategorikan oleh pemanen berpengalaman menjadi mentah, matang, dan lewat matang. Tiga bagian TBS yaitu pangkal, tengah, dan ujung disinari laser dioda 640 nm mengenai 5 buah pada tiap bagian. Kemudian citra direkam mengunakan kamera CMOS monokrom. Selanjutnya 15 buah tersebut diuji tingkat kekerasan mengunakan penetrometer. Klasifikasi tingkat kematangan dilakukan mengunakan K-mean clustering. Hasil penelitian memperlihatkan bahwa metode pencitraan fluoresensi yang diinduksi laser potensial digunakan dalam mengklasifikasi tingkat kematangan TBS. Tingkat kekerasan buah berkorelasi positif terhadap tingkat keabuan citra TBS. K-mean clustering memperlihatkan tiga kelompok tingkat kematangan yang terdiri dari 0, 1 dan 2. Ripeness levels of oil palm fresh fruit bunches (FFB) are the main factor to determine the quality of crude palm oil (CPO) produced by Oil Palm Mill. Sorting oil palm FFB after harvest or before entering the boiling process is generally done manually which relies on human vision and experience. Imaging methods has developed vastly due to advances in computer and image processing techniques. This study used a laser-induced fluorescence imaging to access and classify the ripeness levels of oil palm FFB of Tenera variety. The relationship between gray value and the level of firmness of FFB fruit was analyzed. The samples consisted of 27 oil palm FFB categorized  by experienced harvester as unripe, ripe, and overripe. Laser light was shone on equatorial part of each FFB such that 5 fruitlets were covered by laser light, then the image of the front part was acquire using a monochrome CMOS camera. The step was repeated for basil and apical parts in sequent. All 15 fruitlets were testing for the firmness level using a penetrometer. Ripeness level classification was done using K-mean clustering. The results showed that the laser-induced fluorescence imaging method are potential to be used to determine the ripeness levels of FFB. The fruit firmness is positively correlated with the gray value of the image of FFB. K-mean clustering shows three ripeness centroid of 0, 1 and 2 . Keyword: Fluorecence Imaging, Oil Palm, Fresh Fruit Bunches, Firmness, Laser Induced Fluorecence

Honey is a natural sweet substance which is often mixed with other liquids for health purposes or as a sugar substitute in variety of food. Due to high commercial profit, many fraudulent acts have been around to add other substances to pure honeys. This study used two spectroscopic methods which are the laser induced fluorescence (LIF) and Fourier Transform Infrared (FTIR) spectroscopy to differentiate pure and corn syrup adulterated honeys based on sugar content. LIF used a 405 nm diode laser as the excitation laser. Samples of 27 were prepared for this study. They composed of 15 pure honey and 2 non honeys, and 10 adulterated honeys which we coded from A to Q.. Non honey samples were pure date syrup and corn syrup which coded as K and L. The sugar contents were measured manually using a brix refractometer which resulted the honey sugar contents range of 69.5 % to 78 %. The peak wavelengths observed range from There is R2 = 0.80 correlation between peak wavelength of fluorescence colours to sugar contents. The results showed that the peak wavelengths range from 490.9 nm to 641.3 nm. LIF was able to differentiate between the pure honeys than the adulterated or mixed ingredient honeys except for sample C. The differences of FTIR spectrums were shown by honey samples which was not given corn syrup adulteration, where the difference begins to be seen clearly at the wave number range 1150 cm−1 to 650 cm−1.

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Abstract. The ripeness of the oil palm Fresh Fruit Bunches (FFB) determines the yield of the oil produced. Traditionally there are two ways to determine FFB ripeness which are the number of loose fruits and the color changes. Nevertheless, one drawback of visual determination is subjective and qualitative judgment. In this study, the FFB ripeness was investigated using laser based image processing technique. The advantages of using this technique are non-destructive, simple and quantitative. The working principle of the investigation is that a FFB is inserted into a light tight box which contains a laser diode and a CMOS camera, the FFB is illuminated, and then an image is recorded. The FFB image recorder was performed on four FFB fractions i.e. F0, F3, F4 and F5 on the front and rear surfaces at three sections. The recorded images are speckled granules that have light intensity variation (bio-speckle imaging). The feature extracted from the specked image is the contrast value obtained from the average gray value intensity and the standard deviation. Based on the contrast values, the four fractions of FFB can be grouped into three levels of ripeness of unripe (F0), ripe (F3) and overripe (F4 and F5) on the front surface of base section of FFB by 75%.