Processing of coconut sap into sugar syrup using rotary evaporation, microwave, and open‐heat evaporation techniques

Abstract

Background: Coconut sugar has a caramel color with a taste like brown sugar. It is commonly used as natural sweetener. However, coconut sugar has been produced from coconut sap using a traditional method that involves heating the sap at high temperature (>100 °C) in an open pan for a long period (3-5 h). This conventional method results in an over-cooked sugar, which leads to quality deterioration in terms of both its physical and chemical properties. The current study aimed to investigate the processing of coconut sap into sugar syrup using alternative processing techniques such as rotary vacuum evaporation (RE) and microwave evaporation (ME), comparing them with open-heat evaporation (OHE) technique. Results: Coconut sugar syrup produced by rotary evaporation at 60 °C and 250 mbar vacuum (RE-60) required the shortest production time (12.2 min) and the lowest processing temperature (54.8 °C) when compared with ME (13 min and 103.2 °C) and OHE (46.8 min and 101.6 °C). It also had a light brownish color with a higher L* value (35.17) than the ME (29.84) and OHE (23.84) methods.It was found to contain higher amounts of monosaccharides (fructose and glucose) and lower amounts of disaccharides (sucrose). Furthermore, the amount of energy required for RE-60 (0.35 kWh) was much less than for OHE (0.83 kWh). Conclusion: This study provided an alternative processing method for the sugar processing industry to produce coconut sugar using the rotary evaporation method at 60 °C under 250 mbar vacuum with better physicochemical qualities, shorter processing time, and minimum input energy.

A preliminary investigation of caramelisation and isomerisation of allulose at medium temperatures and alkaline pHs: a comparison study with other monosaccharides

“…In addition, different processing methods can also affect the sugar profiles. Previous studies have shown that several methods conducted on coconut sap, such as rotary evaporation and microwave, resulted in different sugar profiles and physicochemical properties (Asghar et al ., 2020c,b).…”

Coconut Sugar: Chemical Analysis and Nutritional Profile; Health Impacts; Safety and Quality Control; Food Industry Applications

“…Therefore, they should be increasingly used [ 20 ]. For studying organic constituents, the non-volatile ones are analyzed mainly by high-performance and ultrahigh liquid chromatography (HPLC/UHPLC) coupled to different detectors (e.g., refractive index (RI), mass spectrometry (MS), UV-Vis), while volatile ones are determined mostly by GC–MS (gas chromatography coupled to mass spectroscopy) (e.g., [ 21 , 22 , 23 ]). Indeed, coupling a chromatography system (e.g., UHPLC/HPLC or GC) to a mass spectrometer is one of the most powerful ways to identify and quantify compounds because this analytical strategy provides two different types of data per run analysis: (i) retention time and (ii) mass spectral pattern (molecular ion and fragmentation), for each separated compound.…”

Дослідження Мікрохвильового Вакуум-Випарного Модуля Безперервної Дії

“…Аналіз літературних джерел та формулювання проблеми Серед існуючих методів концентрування харчових розчинів найбільш поширеним є випарювання, що забезпечує отримання якісного харчового концентрату при відносно невисоких витратах на обладнання [7, ]. Досить високу популярність набирають дослідження даного процесу з використанням мікрохвильових ( ) технологій на прикладі різних фруктових і овочевих соків: ананасу [9,10], яблука [11], кокосу [12], гранату, винограду, моркви [13]. одібний науковий ажіотаж обумовлюється високими якісними показниками готового продукту, оскільки при електромагнітному підводі енергії відсутня класична теплопередача, що в свою чергу унеможливлює утворення прикордонного шару і, як наслідок, продукт не набуває присмаку варіння.…”