Near Infrared Spectroscopy: A Rapid and Non-Destructive Technique to Assess the Ripeness of Oil Palm (Elaeis Guineensis Jacq.) Fresh Fruit

Abstract

Near infrared (NIR) spectroscopy as a rapid and non-destructive technique was used with principal component analysis and linear discriminant analysis to develop an alternative technique for oil palm fresh fruit ripeness classification. The fruit samples were broadly classified into four main ripeness grades: unripe, under-ripe, ripe and over-ripe. A total of 3870 samples of individual fruits were taken at different stages of ripeness between 6 and 27 weeks after anthesis. Right after field collection, fresh samples were sent immediately to the laboratory for NIR and wet chemistry analysis. Two parameters, oil and moisture content in mesocarp were used as prior reference to determine the ripeness grades of oil palm fresh fruit. The NIR spectra of the ripe and over-ripe grades had higher absorbance compared to the unripe and under-ripe grades. The overall average accuracy of the classification by ripeness grades using this technique for both the training and the validation set samples was larger than 81%. In practical application, the rapid and non-destructive NIR technique has potential use for classifying oil palm fresh fruit into ripeness grades.

Classification of oil palm fresh fruit maturity based on carotene content from Raman spectra

“…However, the quality of the image is subjected to different lighting environments such as sun light exposure, illumination and shadow. Next to imaging, spectroscopy has gained increasing attention among researchers, such as absorption spectroscopy method using a portable ultraviolet–visible (UV–Vis) spectrometer 6 and NIR spectroscopy 29 . Besides absorption property, measurement of the fluorescence property of the oil palm bunch using fluorescence sensor has also been previously introduced 30 .…”

Rapid determination of oil content in dried-ground oil palm mesocarp and kernel using near infrared spectroscopy

“…This process allowed for analyzing the data variation, explaining the structure of variables and reducing the original spectra information algorithmically into a small number of linearly relevant variables. 18,23 The new obtained variables were then used to compute the population center and the distance from each sample in the population which was expressed as the Mahalanobis distance (Global H or GH). Samples with a low GH ≤ 3 were accepted and the remaining samples with GH > 3 were considered as outliers.…”

“…17 NIR spectroscopy has also been successfully used for ripeness assessment of palm oil fruit. 18 Due to its versatility, NIR spectroscopy offers a great potential to the palm oil industry such as for supporting bunch analysis in breeding trials. A faster time of oil content analysis of mesocarp and kernel will provide opportunities for breeding programs to assess the oil content in a higher number of samples and in a more environmental friendly way.…”

Novel extraction, rapid assessment and bioavailability improvement of quercetin: A review

“…NIRS is another non-destructive spectroscopic approach, works best in spectra ranging from 780 to 2500 nm, detecting chemical bonds in a sample such as O–H, C–H, N–H, and S-H [56] , [57] . During an examination of a sample, the chemical bonds (in a sample) absorb spectral energy while, remaining NIR frequencies either reflect or transmit with different wavelengths, which are calculated by the detectors [58] . However, the method still possesses some weaknesses which limit its wider research applications.…”