加工條件影響酸化椰奶飲料品質安定性之研究

Abstract

Pina Colada乃由椰奶、鳳梨、水及砂糖調配而成的飲料，此產品在中南美洲相當盛行，由於椰奶成分中富含油脂，在貯藏過程中極易發生油水分層現象，影響消費者對產品的接受度，本論文將以酸化椰奶飲料進行探討（1）pH值及均質條件對酸化椰奶飲料品質之影響；（2）酸化椰奶飲料在不同溫度貯藏下，對色澤、混濁度、黏稠度、溶液分層指數、酸價、過氧化價之變化；（3）酸化椰奶飲料添加不同膠體，在不同均質條件及糖度下對品質及混濁穩定性之影響；（4）添加不同量之alpha-tocopherol對酸化椰奶飲料中油脂安定性之影響。 酸化椰奶飲料的品質經不同均質條件處理及pH值改變而有所變化，將酸化椰奶飲料pH值分別調至3.0、4.0靜置兩小時後，經調酸至pH 3.0極易發生油水分層的現象，將酸化椰奶飲料之pH值調至4.0再以8000rpm均質五分鐘，經貯藏兩小時內，色澤、混濁度、黏稠度、溶液分層指數均能維持較佳的程度。 酸化椰奶飲料以不同的均質轉速處理後，以100℃熱處理2分鐘後，分別在37±2℃及25±2℃貯藏一個月後，色澤、混濁度、黏稠度、溶液分層指數於37±2℃貯藏下會明顯較25±2℃下降。不同均質條件處理雖無法明顯改善分層現象發生，但有助於提昇酸化椰奶飲料之色澤、混濁度及黏稠度。 12oBrix、18oBrix酸化椰奶飲料 (pH4.0)分別添加0.04％、0.06％、0.08％三仙膠及0.2％、0.4％、0.6％果膠，經不同均質條件處理，以100℃熱處理2分鐘後，貯藏於25±2℃的過程中，添加0.08％三仙膠於12oBrix、18oBrix酸化椰奶飲料，以18oBrix更能維持較佳的黏稠度、混濁度、溶液分層指數。添加果膠對於酸化椰奶飲料之混濁穩定性而言，並無法有效改善產品的混濁穩定性。添加30ppm之alpha-tocopherol於酸化椰奶飲料中，即可有效延緩產品之酸價及過氧化價在25℃貯藏期間上升。

Pina Colada is a drink which is made of coconut milk, pineapple, water and sugar and this product was very popular in Central and South America. Due to the ingredient of coconut milk containing lipid, the Pina Colada causes the phenomenon of creaming and being rancid in the process of storage and it influences the customers’ acceptance to this product. This essay probes about the acidified coconut drinks：(1) How the pH value and the condition of homogenization affect the quality of acidified coconut drinks. (2) When the acidified coconut drinks is stored in different temperatures, how the hue, turbidity, viscosity, creaming index, acid value and peroxide value change. (3) Because the acidified coconut drinks are added the different hydrocolloid, how the hydrocolloid affects the quality and the cloud stabilization in the different condition of homogenization and soluble solid. (4) How it affects the lipid stability in the acidified coconut drinks when adding alpha-tocopherol with different quantity. The quality of acidified coconut drinks changes because of the different conditions of homogenization and the variety of pH value, when the pH value of it has been adjusted separately into 3.0 and 4.0, and it has to be place for 2 hours. The pH 3.0 being adjusted acid easily causes the phenomenon of creaming. However, if the acidified coconut drinks is adjusted to pH4.0 and homogenized for 5 minutes with 8000rpm, the hue, turbidity, viscosity, creaming index can be maintained in better level. After being handled in different homogenization rotor, the acidified coconut drinks has to under the heat treatment in 100℃ for 2 minutes and be stored separately to a temperature of 37±2℃and 25±2℃ for 1 month. Finally, we will observe that the hue, turbidity, viscosity, creaming index must decrease obviously. Although the different conditions of homogenization handling can’t clearly improve the happening of creaming. It exactly contributes to promote the hue, turbidity, viscosity of acidified coconut milk. The peroxide value and acid value will raise by the increasing of storage time, and it shows that the products oxidize seriously during the storage time. The acidified coconut drinks (pH4.0) of 12oBrix、18oBrix is respectively added the xanthan gum of 0.04％, 0.06％, 0.08％ and the pectin of 0.2％, 0.4％, 0.6％. Through the different the different conditions of homogenization handling, the acidified coconut drinks is under the heat treatment in 100℃ for 2 minutes. And in the process of storing at the temperature of 25±2℃, the acidified coconut drinks of 18oBrix which is added the xanthan gum of 0.08％ can maintain better viscosity, turbidity than 12oBrix. It can not maintain the cloud stabilization when add the pectin to the acidified coconut drinks. The acidified coconut drinks adding the alpha-tocopherol in 30ppm can efficiently delay the acid value and peroxide value of the product which is stored at the temperature of 25℃ to raise.