Cheftel C, Bousquet-Ricard M, Quayle G, Guilbert S, Elguezabal L, Masset R
Ann Nutr Aliment. 1978;32(2-3):597-615.
The aim of this study was to prepare concentrated foods (20-40 p. 100 water), edible as such, chemically and microbiologically stable, nutritionally balanced, and which could be used as meal substitutes (travel, camping, snacks, etc.). With high methoxyl pectins, it was possible to obtain a pectic gel (pH 3,5), similar to a fruit jelly, but containing 20 p. 100 d.w. protein, and less sucrose. Water activity (Aw) was 0,75-0,78, for a 25 p. 100 water content, as a result of adding glucose syrup and sorbitol. After 4 months storage at 20 or 38 degrees C in aluminium pouches, no mold growth was detected (even following prior inoculation) nor practically any change in flavor, texture of Aw. With low methoxyl pectins, gel foods richer in water (35 p. 100), softer, less acid (pH 4,3) and containing even less sugars have been prepared (26 p. 100 d.w. protein, 35 p. 100 carbohydrates, 15 p. 100 lipids). Aw was lowered to 0,84 by adding humectants (sucrose, glycerol, sorbitol, citric acid, sodium citrate and chloride). Starch gels (40 p. 100 starch/d.w.), of pH less than 4,5, containing proteins and lipids, were flavored with vegetale powders. For 30 p. 100 water and with humectants, Aw was 0,84-0,88. The texture changes more or less favorably with time according to the nature of the starch used. Using the technology of processed cheeses, protein gels were made with either of the following characteristics: 1. A reduced Aw (0,86, for 38 p. 100 water) by adding humectants, but with a soft texture similar to that of a processed swiss cheese; 2. The same reduced Aw, with a starch content of 26 p. 100/d.w., and a harder texture, comparable to that of Emmenthal cheese.
本研究的目的是制备浓缩食品（含水量20%-40%），这种食品可直接食用，在化学和微生物学上稳定，营养均衡，可用作代餐食品（旅行、露营、零食等）。使用高甲氧基果胶，可以获得一种果胶凝胶（pH 3.5），类似于果冻，但含有20%（干重）的蛋白质和较少的蔗糖。由于添加了葡萄糖浆和山梨醇，对于含水量为25%的产品，水分活度（Aw）为0.75-0.78。在铝箔袋中于20℃或38℃储存4个月后，未检测到霉菌生长（即使事先接种），Aw、风味和质地实际上也没有任何变化。使用低甲氧基果胶，制备出了含水量更高（35%）、更软、酸度更低（pH 4.3）且含糖量更低的凝胶食品（26%干重蛋白质、35%碳水化合物、15%脂质）。通过添加保湿剂（蔗糖、甘油、山梨醇、柠檬酸、柠檬酸钠和氯化钠），Aw降至0.84。pH小于4.5、含有蛋白质和脂质的淀粉凝胶（40%淀粉/干重）用蔬菜粉调味。对于含水量为30%且添加了保湿剂的产品，Aw为0.84-0.88。根据所用淀粉的性质，质地会随时间或多或少地发生有利变化。利用加工奶酪技术，制备出了具有以下任一特性的蛋白质凝胶：1. 通过添加保湿剂降低Aw（对于含水量38%的产品，Aw为0.86），但质地柔软，类似于加工瑞士奶酪；2. 同样降低Aw，淀粉含量为26%/干重，质地更硬，类似于埃门塔尔奶酪。
