Aly M E
Department of Food Science, Faculty of Agriculture, Zagazig University, Egypt.
Nahrung. 1996 Aug;40(4):194-200. doi: 10.1002/food.19960400407.
An attempt was carried out for prolongation of the shelf-life of Mozzarella cheese by incorporation of potassium sorbate into the cheese. Three manufacturing techniques were used: a) addition of potassium sorbate to kneading water (at level of 6%), b) addition during brine salting (at level of 0.5%) and c) dipping the cheese into potassium sorbate solution (6%) directly prior to packaging. Control cheese was made without potassium sorbate treatment. The resulting cheeses were divided into two portions, one of which was contaminated with Penicillium roqueforti and then packaged, while the second one was packaged without contamination. Both were stored at refrigerator (5 +/- 1 degree C) temperature and analysed periodically until spoilage. The results showed that treatment with potassium sorbate did not affect the organoleptic properties of the cheeses, except that a slight objectionable bitter flavour was observed in fresh cheeses treated with sorbate using the techniques of dipping or in brine salting then it was disappeared during storage. However, the overall acceptabilities of the sorbate-treated cheese were increased up to 10 weeks of storage compared with 4 weeks for untreated cheeses. Treatment with potassium sorbate in kneading water or brine appeared to be more effective than dipping. Addition of potassium sorbate inhibited microbial growth, especially that of moulds and yeasts. The sorbate-treated cheeses had higher moisture, pH values and lower acidity than the control. Fat, salt and total nitrogen were unaffected during storage. Levels of soluble N, non-protein N and total volatile fatty acids in sorbate-treated cheeses were slightly higher than in the control. Furthermore, addition of potassium sorbate increased the meltability and improved the fat leakage of Mozzarella cheese.
通过在马苏里拉奶酪中添加山梨酸钾来延长其保质期。采用了三种制作工艺：a）在揉面水中添加山梨酸钾（含量为6%），b）在盐水腌制过程中添加（含量为0.5%），c）在包装前直接将奶酪浸入山梨酸钾溶液（6%）中。对照奶酪未经过山梨酸钾处理。将制成的奶酪分成两份，其中一份用罗克福青霉污染后包装，另一份未受污染直接包装。两份奶酪均储存在冰箱（5±1℃）温度下，并定期进行分析直至变质。结果表明，山梨酸钾处理对奶酪的感官特性没有影响，只是在用浸入法或盐水腌制法处理的新鲜奶酪中观察到有轻微的不良苦味，但在储存过程中苦味消失。然而，与未处理的奶酪储存4周相比，经山梨酸钾处理的奶酪在储存长达10周时总体可接受性有所提高。在揉面水或盐水中添加山梨酸钾似乎比浸入法更有效。添加山梨酸钾可抑制微生物生长，尤其是霉菌和酵母菌的生长。经山梨酸钾处理的奶酪比对照奶酪具有更高的水分、pH值和更低的酸度。在储存过程中，脂肪、盐分和总氮含量不受影响。经山梨酸钾处理的奶酪中可溶性氮、非蛋白氮和总挥发性脂肪酸的含量略高于对照奶酪。此外，添加山梨酸钾可提高马苏里拉奶酪的可熔性并改善其脂肪渗出情况。
