การพัฒนาผลิตภัณฑ์ขนมไทยจากน้ำเชื่อมลำไยตกเกรด

Abstract

evelopment of Thai Dessert Products from Low-Grade Longan Syrup has following objectives. 1) To study the physical, chemical properties of, and bioactive chemicals in low-grade longan 2) To study the syrup making process and to find the appropriate concentration for Thai dessert products from low-grade longan syrup 3) To test sensory acceptance of the produced Thai dessert products from low-grade longan syrup. 4) To study physical and chemistry transformation during storage of the produced Thai desserts from low-grade longan syrup. 5) To pass on the knowledge of producing syrup from low-grade longan for producing Thong Muan and Aalua desserts. From the study of physical and chemical properties, it was found that the off-season low-grade longan had physical and chemical properties that is different from the longan that is sold in the market. This is because the quality of the longan used is not of the standard quality. They are small in size, or maybe scrapped, or its flesh is dull. The water activity value of the low-grade longan exceeds the standard. The low-grade longan was extracted with different methods. it was found that the extraction method by boiling with a pressure cooker had the highest content of polyphenols. The extract is dark in color, but the total dissolved solids and pH were lower than other methods. To study the syrup process, extraction from boiling with a pressure cooker were selected by simmering 1,000 grams of extract for 1 hour. It was found that syrup from seedless fresh longan was the most suitable. The resulting syrup is clear, reflective, dark brown liquid with high viscosity. It had sweet taste and smell of longan. The syrup concentration was suitable for Thai dessert products including Thong Muan dessert with 20% low grade longan syrup and Aalua dessert with 5% low grade longan syrup. When compared with the standard recipe, it was found that both types of Thai desserts were darker than the standard formula, containing nutrients and water activity and energy close to the standard formula. The addition of the low-grade longan syrup resulted in the product containing more polyphenols. When both types of Thai desserts were studied for storage effects, it was found that all aspects of preference score tended to decline. Desserts are slightly darker in color, have water activity value, peroxide content, and texture that is crispier and more solid. Knowledge transfer of longan syrup production process to the community Ban Hong District, Lamphun Province, found that the participants were satisfied with the process, knowledge, time, and location of the knowledge transfer the most. As for the utilization aspect, the participants were very satisfied.