Stefanon Bruno, Procida Giuseppe
Dipartimento di Scienze della Produzione Animale, Università di Udine, 33100 Udine, Italy.
J Dairy Res. 2004 Feb;71(1):58-65. doi: 10.1017/s0022029903006563.
Effects of including silage in the diet on volatile compound profiles and their modification during ripening of Montasio cheeses were examined. Twelve farms were selected and grouped according the type of forage in the ration: hay-based diets (four farms); hay and corn silage-based diets (four farms); and diets based on hay, corn silage and grass silages (four farms). For cheesemaking, 1000 kg of milk collected from two consecutive milkings was sampled from each farm and processed in the same cheese factory. Cheeses were ripened in the same cellar, in controlled humidity (78-85% relative humidity) and temperature (9-12 degrees C), until analysis. After 68 (62-74), 200 (194-206) and 360 (354-366) d of ripening, a cheese from each batch was analysed for moisture, protein and fat, volatile fatty acids (VFA) and volatile compounds. These latter were analysed by dynamic reverse carrier gas headspace gas chromatographic mass spectrometry (GC-MS) technique, scanning from m/z 29 to m/z 300 at 0.5 s cycle time. Total and individual VFA contents of cheeses did not differ between the different dietary treatments and increased linearly (P<0.01) during ripening, indicating that there were no appreciable defects of fermentation. Sixty-two volatile compounds were identified in the cheese samples: 12 aldehydes, 9 ketones, 16 alcohols, 17 esters, 2 hydrocarbons, 4 sulphur-containing compounds and 2 terpenes. Diet significantly affected the amount of total alcohols, ethanol, isobutanol, 1-penten-3-ol, 2-methyl-1-butanol and the sum of all the volatile compounds. Significant variations of 33 volatile compounds (9 aldehydes, 4 ketones, 6 alcohols, 10 esters, 1 hydrocarbons, 2 sulphur containing compounds, and 1 terpene) were observed during ripening. These results suggest that the influence of diet composition on volatile compounds of matured cheeses are related more to effects on microbial and chemical fermentations in cheese during ripening rather than to a direct transfer of molecules from milk.
研究了在蒙塔希奥奶酪成熟过程中，日粮中添加青贮饲料对挥发性化合物谱及其变化的影响。选取了12个农场，并根据日粮中草料的类型进行分组：以干草为基础的日粮（4个农场）；以干草和玉米青贮为基础的日粮（4个农场）；以及以干草、玉米青贮和青草青贮为基础的日粮（4个农场）。用于制作奶酪的牛奶，从每个农场连续两次挤奶收集的1000千克牛奶中取样，并在同一奶酪工厂进行加工。奶酪在同一地窖中成熟，控制湿度（相对湿度78 - 85%）和温度（9 - 12摄氏度），直至进行分析。在成熟68（62 - 74）天、200（194 - 206）天和360（354 - 366）天后，对每批中的一块奶酪进行水分、蛋白质、脂肪、挥发性脂肪酸（VFA）和挥发性化合物分析。挥发性化合物通过动态反向载气顶空气相色谱 - 质谱联用（GC - MS）技术进行分析，在0.5秒的循环时间内从m/z 29扫描至m/z 300。不同日粮处理之间奶酪的总VFA和单个VFA含量没有差异，且在成熟过程中呈线性增加（P<0.01），表明没有明显的发酵缺陷。在奶酪样品中鉴定出62种挥发性化合物：12种醛、9种酮、16种醇、17种酯、2种烃、4种含硫化合物和2种萜类化合物。日粮显著影响总醇类、乙醇、异丁醇、1 - 戊烯 - 3 - 醇、2 - 甲基 - 1 - 丁醇的含量以及所有挥发性化合物的总量。在成熟过程中观察到33种挥发性化合物（9种醛、4种酮、6种醇、10种酯、1种烃、2种含硫化合物和1种萜类化合物）有显著变化。这些结果表明日粮组成对成熟奶酪挥发性化合物的影响，更多地与成熟过程中对奶酪微生物和化学发酵的影响有关，而不是与分子从牛奶中的直接转移有关。
