Abstract

Storage stability of concentrated oil-in-water beverage emulsions subjected to thermal and non-thermal processing was evaluated over 14 days at 22 °C. Emulsions were made with canola oil and aqueous dispersions of Type “A” and Type “B” gelatin and xanthan. They were also conjugated with propylene glycol alginate (PGA), modified starch and modified gum Arabic was studied at pH 3.4 and 7.0. Increase in apparent viscosity was observed with storage for gelatin Type “A” emulsions (pH 7.0) and gelatin Type “B” emulsions (pH 3.4). All emulsions showed shear-thinning behavior associated with droplet flocculation. Increase in the slope of particle size distribution was more obvious for protein (gelatin) stabilized emulsions. Concentrated gelatin Type “A”-modified starch had smaller particle size and greater stability at pH 3.4, followed by gelatin Type “B”-modified starch and gelatin Type “B”-xanthan-PGA both at pH 7.0. Simulated orange beverage (pH 3.0) and dairy beverage (pH 6.8) using stabilized emulsions were pasteurized by heat and high pressure. Emulsions formulated by modified starch produced better stability in both beverage types. Gelatin Type “A” and modified starch conjugate resulted in greater stability compared to other conjugated emulsions. However, gelatin alone failed to stabilize the emulsion systems. The ringing was characteristically associated with emulsions formed with gelatin alone. Neither thermal processing nor high-pressure treatment resulted in destabilization of emulsions.

摘要

在 22 °C 下对经过热处理和非热处理的浓缩水包油饮料乳液的储存稳定性进行了 14 天的评估。乳液由菜籽油和“A”型和“B”型明胶和黄原胶的水分散体制成。它们还与海藻酸丙二醇酯 (PGA)、改性淀粉和改性阿拉伯树胶结合，在 pH 3.4 和 7.0 下进行了研究。随着明胶“A”型乳液（pH 7.0）和明胶“B”型乳液（pH 3.4）的储存，观察到表观粘度增加。所有乳液都显示出与液滴絮凝相关的剪切稀化行为。对于蛋白质（明胶）稳定的乳液，粒度分布斜率的增加更为明显。浓缩明胶“A”型改性淀粉在 pH 3.4 时具有更小的粒径和更高的稳定性，其次是明胶“B”型改性淀粉和明胶“B”型-黄原胶-PGA，pH均为7.0。使用稳定乳液的模拟橙汁饮料 (pH 3.0) 和乳制品饮料 (pH 6.8) 通过加热和高压进行巴氏杀菌。由改性淀粉配制的乳液在两种饮料中都具有更好的稳定性。与其他共轭乳液相比，“A”型明胶和改性淀粉共轭物具有更高的稳定性。然而，单独的明胶不能稳定乳液体系。振铃特征与单独用明胶形成的乳液有关。热处理和高压处理都不会导致乳液不稳定。8) 使用稳定的乳液通过加热和高压进行巴氏消毒。由改性淀粉配制的乳液在两种饮料中都具有更好的稳定性。与其他共轭乳液相比，“A”型明胶和改性淀粉共轭物具有更高的稳定性。然而，单独的明胶不能稳定乳液体系。振铃特征与单独用明胶形成的乳液有关。热处理和高压处理都不会导致乳液不稳定。8) 使用稳定的乳液通过加热和高压进行巴氏消毒。由改性淀粉配制的乳液在两种饮料中都具有更好的稳定性。与其他共轭乳液相比，“A”型明胶和改性淀粉共轭物具有更高的稳定性。然而，单独的明胶不能稳定乳液体系。振铃特征与单独用明胶形成的乳液有关。热处理和高压处理都不会导致乳液不稳定。振铃特征与单独用明胶形成的乳液有关。热处理和高压处理都不会导致乳液不稳定。振铃特征与单独用明胶形成的乳液有关。热处理和高压处理都不会导致乳液不稳定。