Measurements of Juice Quality Using Ultrasonic Technology

糖度及黏度是食品加工製造過程中，口感好壞重要性的科學指標。因此，加工過程中，如果能即時進行上述的量測，並據以進行調整製程參數，便可達到最佳的產品品質。本研究是利用低功率超音波量測，配合研發的硬體及軟體，可同時量測波速及衰減係數，不會對被檢測物產生任何微結構上的破壞，評估波速與衰減係數兩項超音波特性與糖度值及黏度值彼此之間的關係，建立最佳應用模式，達到產品品質監控的功能。 不同濃度糖水實驗量測方法，溫度控制在30℃之條件下，進行量測糖度值及黏度值，採用回波法，並探討超音波波速、衰減係數與糖度及黏度間之關係。實驗結果顯示，超音波波速會隨著糖度及黏度的增加而增加，都呈現正相關性，波速與糖度及黏度線性關係良好，判定係數分別高達0.966及0.9099。但在同樣實驗條件之下，超音波衰減係數與糖度及黏度彼此的相關性較低。在相同實驗操作下，進一步對混合西瓜汁及混合柳丁汁進行糖度及黏度檢測。檢測結果得知，超音波波速隨著混合西瓜汁及柳丁汁之糖度及黏度的增加而增加，波速與混合西瓜汁内所含糖度及黏度的線性關係良好，判定係數分別高達0.9882及0.9621。混合柳丁汁以回波法及穿透法進行檢測，波速與糖度呈線性正相關，判定係數分別高達0.9877及0.9978；波速與黏度也呈現正相關，判定係數分別為0.957及0.9867。超音波波速可精確評估混合西瓜汁及混合柳丁汁內的糖度值及黏度值，可提供一套非破壞且即時應用於混合果汁生產製程設計上的參考。The sugar content and the viscosity are an important scientific sensory indicator for processed foods. Food products can arrive at an optimum sensory quality if the production process can be adjusted on line through monitoring the above two factors in real time. Thus, it is the objective of this study to develop a real-time ultrasonic monitoring system that provides information about the sugar content and viscosity in juices via the detected ultrasonic velocity and power attenuation. The two sensory indices are estimated using the ultrasonic measurements with derived mathematic equations. The study was initiated in aqueous sugar solutions. Ultrasonic measurements were conducted using the pulse-echo (PE) or the transmission-through (TT) schemes at a temperature-controlled environment of 30℃. The velocity of ultrasound increases proportionally to increased sugar content and viscosity in the solution. The power attenuation coefficient does not show rational relationship with the two sensory indices. The velocity of ultrasound has strong linear correlations with the sugar content at R2=0.966 and with the viscosity at R2=0.9099. The established procedures were applied to watermelon and orange juices at various sugar contents and viscosities. In a PE scheme, the velocity of ultrasound exhibits R2=0.9882 for sugar content and R2=0.9621 for viscosity in watermelon juice and R2=0.9877 for sugar content and R2=0.957 for viscosity in orange juice. In a TT scheme, the coefficients of determinant are 0.9978 and 0.9867 for sugar content and viscosity respectively in orange juice. The strong correlation and the convenience in equipment operation would allow the use of ultrasound in on-line monitoring for automated juice production and furthermore, other food processing.摘要 I Abstract II 目錄 III 圖目錄 V 表目錄 VII 符號表 VIII 第一章 緒論 1 1-1前言 1 1-2研究目的 3 第二章 文獻探討 4 2-1超音波特性 4 2-1-1超音波的模態 4 2-1-2超音波的頻率、波速與波長 6 2-1-3超音波功率強度 7 2-1-4超音波的衰減 8 2-1-5超音波的生成 9 2-2超音波技術 11 2-2-1非破壞性檢測技術上的應用 11 2-2-2液體黏度與糖度量測上的應用 13 2-2-3農業上的應用 14 2-2-4洗淨上的應用 15 2-2-5乳製品檢測上的應用 15 第三章 超音波量測系統 17 3-1理論基礎與量測方法 17 3-1-1超音波對糖度及黏度的檢測 17 3-1-2超音波回波法的量測 19 3-1-3超音波穿透法的量測 21 3-2超音波量測系統設備 24 第四章 糖水及果汁特性的量測 28 4-1實驗儀器設備 28 4-2實驗材料 29 4-3物理特性的量測方法 30 4-3-1糖度的量測方法 30 4-3-2黏度的量測方法 31 4-4糖水的準備與量測方法 31 4-4-1糖水的準備 31 4-4-2超音波對糖水的量測方法 33 4-5超音波在果汁量測上的應用 34 4-5-1果汁樣本的準備 34 4-5-2超音波對果汁的量測方法 34 第五章 結果與討論 36 5-1糖水的量測 36 5-1-1糖水糖度、黏度及密度與濃度的關係 36 5-1-2超音波波速與糖水密度、糖度及濃度的關係 38 5-1-3超音波波速與糖水黏度的關係 40 5-1-4超音波衰減係數與糖水糖度及黏度的關係 42 5-1-5超音波波速檢測在糖水糖度與黏度上的應用 44 5-2西瓜汁的量測 45 5-2-1超音波波速與西瓜汁密度及糖度的關係 45 5-2-2超音波波速與西瓜汁黏度的關係 47 5-2-3超音波衰減係數與混合西瓜汁糖度及黏度的關係 49 5-3柳丁汁的量測 52 5-3-1超音波波速與柳丁汁密度及糖度的關係 52 5-3-2超音波波速與柳丁汁黏度的關係 55 5-3-3超音波衰減係數與混合柳丁汁糖度及黏度的關係 58 第六章 結論與建議 62 6-1結論 62 6-2建議 63 參考文獻 64 附錄 70 A. 量測儀器 70 B. 黏度計實驗步驟 7

The Study on Autonomous Navigated Vehicle for Agriculture

本研究內容主要為研發一油壓驅動的四輪驅動及四輪轉向自動導引車 ，具有迴轉半徑小，扭矩高及富機動性等優點，由於此導引車對行走路徑 校正容易，適於自動循跡系統使用。 針對電位感測器及導引車之行進轉向特性進行測試，以微處理機預先設定 四個軌跡（直線、 倒U字型、「型、﹁ 型），再驅使導引車依所設定軌 跡進行循跡運動，經由觀察及記錄其循跡的精確度與準確度，進一步了驗 証導引車具有良好的機械性能與循跡性能。 根據試驗結果分析，導引 車在0.477km/hr∼3.13km/hr的範圍內行駛，車速對迴轉半徑甚小，但迴 轉半徑隨著轉向角度的增加而變小電位量測器能準確量測車輪的轉向角度 ，電壓值與轉向角呈線性關係，其相關係數達0.99以上。導引車在預先設 定軌跡的控制的模式下，其四種運動軌跡之重現性、精確度與準確性均高 ，行走性能穩定，循跡性能良好。The purpose of this study is to develop a 4-wheel driven and steering vehicle which is driven with hydraullic power. It is a seif-guide vehicle in movement. The developed vehicle has the good characteristic feature: small turning radium, high torque and mobile,....ect. Since the vehicle has the ability of adjusting its direction in movement easily, it is adapted to become a self-guided automatic vehicle. A liner position transducer is adapted in this study to control and adjust the vehicle direction in movement. For different movement tracks, which are liner, U-shape, 「 shape, and」shape, are designed in advance with a micro- processor. The processor is use to guide the vehicle movement, which follow the designed track. Through observing and recording its movement tracks, the abilities of movement and track tarcing of the developed vehicle are tested and analyzed. According to the experimental results,its moving speed range is 0.477 km/hr to 3.13 km/hr. The speed is irrelevant to the least turning radium. The higher turing angle has the smaller turing radium. The adapted inear position transducer can measure the turning angle precisely. There exists a highly liner relationship between the turing angle and output voltage for linear position transducer, of which correlation coefficient is 0.99. the vehicle is tested with 4 pre-designed tracks, and shows the good features of repetition, precision, stability in movement, and track tracing

適用於台灣全島的完全混合日糧(TMR)有效纖維量與均勻度的檢測技術

This study extends the applicability of an existing technique, which examines the homogeneity of TMR and the content of effective fiber in the product, to island-wide dairy farmers in Taiwan. The technique was developed based on, and has been successfully applied to samples in southern Taiwan. The technique was revised by expanding the distribution of samples from 216 sites/10 farmers in the south to 342 sites/17 farmers on the whole island. TMR of an adequate slimness was produced from baled hay using a multi-purpose TMR truck. The product was examined using a ψ3.81 cm screen on the top followed by the upper screen (ψl.90 cm) and the bottom tray of the standard Penn State particle separator. The probability of the product with a particle size between 10-15 cm was higher than 90%. The screw drill operated at a speed fluctuating less than 10% and at a load varying less than 5%. These operation parameters indicate that the machine was operating at a stable condition. The TMR product has a content of effective fiber between 10-20% and the coefficients of variance of the homogeneity and the content of salt were less than 10%. This is considered as good. The result is identical to the use of a Penn State fourlayer push-pull separator or a Penn State threelayer manual separator. There is no significant difference between silage and forage TMRs when the three-layer handle is applied, especially the middle screen (0.8≦ψ≦l.9 cm). The result shows that the technique, which was developed based on dairy farmers in southern Taiwan, can be applied to all dairy farmers on the island. In practical applications, the technique can be applied on line for material selection and machine tuning to produce a TMR with an adequate effective-fiber content and homogeneity for optimal cow feeding.本研究將原本僅適用於南部地區的既有完全混合日糧(TMR)有效纖維量與均勻度檢測技術進行適域化與全區化，採樣區擴及中北部與東部，由10樣本戶216採樣點增至17樣本戶342採樣點。驗證採兼用型TMR機細切圓形乾草包，用於調製適當細切長度的TMR。採用兼用型TMR機進行原車細切調製，成品檢測採用ψ3.81cm頂段篩結合Penn State三段篩的上段篩(ψ1.90cm)與底段箱。細切長度維持在10-15cm的機率達90%以上；細切圓形乾草包作業時，螺旋鑽運轉數度維持於±10%的變動率內；細切的重量負載變動維持於±5%，表現出穩定的機械運轉；所調製的TMR有效纖維量在10-20%間；均勻度的變異，與食鹽成分的變異係數(CV)對照，均在10%內，屬優質的範圍。當以Penn State四層式推拉篩動或三層式手搖篩動方式處理時，並無顯著的差異。對於新鮮與烘乾的TMR，採用三層式手搖篩動，也無顯著的差異，尤以中段篩(0.8≦ψ≦1.9cm)更為明確。測試結果顯示所建立的南區檢測技術可以應用於台灣全區的酪農：適宜的檢測技術是以新鮮TMR，利用三層式手搖篩動，依指標值判定TMR的有效纖維量與均勻度，結果反饋於原料及機械操控的調整改善，以達理想的餵飼需求