Healthcare foodservice report 1993. Getting ready for reform. Interview by Mitchell Schechter

Hospital foodservice directors & dietitians are facing the greatest challenge of their careers -- to prepare, along with their institutions, for the most thoroughgoing reform of America's healthcare system ever proposed. Healthcare institutions across the country are seeking the means to offer enhanced patient services & gain competitive advantages by forming new alliances, new patient-centered care systems & cost-reduction programs. To aid in these efforts, their foodservices are developing comprehensive cross-training schemes, inter-departmental teams with other service groups & new ways to cut operating subsidies. Here's how five hospital foodservice departments are using cost controls, revenue building, quality management processes & enhanced efficiencies to help their institutions prepare for the changes ahead.     

The politics of a renovation. Interview by Paul King and Donna Boss

Recently, Shands Hospital at the University of Florida in Gainesville completed a $14-million foodservice renovation, one element in an 11-year-long, $100-million hospital-wide expansion project. Having successfully finished the work in her department, Food & Nutrition Services Director Ruby Puckett offers advice to her colleagues about how to stay in control of the renovation process from beginning through to the end.     

大蒜风味物质超声制备的工艺优化

采用混合均匀设计优化了非超声、不同超声场制备大蒜风味物质的工艺,考察了超声频率、超声强度、时间、液料比等因素对大蒜风味物质得率的影响。超声制备最佳工艺条件为双频交变超声28/40kHz,超声强度0.45W.cm-2,时间20min,液料比8∶1,制备能力值为0.061mg.g-1.min-1,相对于非超声、单频超声、双频复合超声制备能力值分别提高了144.0%、17.3%、84.8%。     

固相微萃取气相色谱测定酱油香味成分条件的优化

采用固相微萃取-气相色谱法分析酱油中的香味成分,对萃取时间、萃取温度、加盐浓度、解析时间等条件参数进行了优化,最终确定了用85μm PA萃取头,在10mL样品中加入1g固体NaCl,萃取温度40℃,萃取时间30min,进样口温度230℃,解析3min为最佳分析条件.本方法简单快速,重复性好,干扰少,灵敏度高.     

气相色谱-质谱联用分析砂梨及其果醋的香气成分

通过响应曲面法以固相微萃取对砂梨香气成分的萃取条件进行了优化,得出最优萃取条件为:选用PDMS/DVB(65μm)涂层纤维头,萃取温度46℃,萃取时间45min,盐添加量11%,样品量3.4g。以此萃取条件,运用HS-SPME结合GC/MS联用技术,对水晶梨及果醋的香气组分进行分析,鉴定出砂梨果实中的32种香气组分和果醋中的15种香气组分。     

乳酸乳球菌乳亚种丁二酮变种发酵乳风味成分分析

使用同时蒸馏萃取-气谱-质谱(SDE-CC-MS)技术对乳酸乳球菌乳亚种丁二酮变种发酵乳中风味物质进行了定性及定量分析,经分析有19种成分属于其代谢产生的风味物质,其中酯类4种,醇类1种,杂环化合物1种,短链挥发性脂肪酸5种,羰基化合物8种,其中乙醇、2,3-丁二酮、2,3-戊二酮可及乙酸的含量明显高于其他菌种发酵乳中的相应含量.     

Determination of regional flavor differences in U.S. Cheddar cheeses aged for 6 mo or longer

ABSTRACT:  Cheddar cheese is a widely popular food in the United States. This product is produced in facilities across the United States and often marketed based on region of manufacture, implying that regional differences in flavor character of the cheese exist. This study was conducted to determine if regional differences in flavor exist in the aged U.S. Cheddar cheeses. Three times per year for 2 y, triplicate 18-kg blocks of Cheddar cheese (< 60 d old) were obtained from 19 manufacturing facilities located in 4 major cheese- producing regions/states: California, Northwest, Midwest, and Northeast. A trained sensory panel documented the flavor characteristics of cheeses after 6-, 9-, 12-, 18-, and 24-mo ripening at 7 °C. Regional differences were observed for specific flavors for cheeses manufactured in the Northwest, Midwest, and Northeast across ripening ( P < 0.05), but the specific flavors responsible for these effects were not consistent across ripening. Similarly, cheese make procedure effects were also observed for specific flavors across ripening ( P < 0.05), but these differences were also not consistent across ripening. The impact of region and cheese make procedure on flavor of the aged Cheddar cheeses was small in comparison to consistently documented, facility-specific flavor differences ( P < 0.0001). Flavor profiles of aged Cheddar cheeses were most strongly influenced by practices specific to manufacturing facility rather than region of manufacture.     

响应面法优化同时蒸馏法萃取熏马肠中挥发性风味物质的研究

使用同时蒸馏萃取法萃取熏马肠中挥发性风味物质,在单因素实验基础上采用Box-Behnken实验设计对提取条件进行优化。结果表明,使用二氯甲烷为提取溶剂,最佳萃取条件为提取时间156 min,溶剂用量50 m L,料液比1∶2.4,在此最优条件下提取量为875.63 mg/kg。气相色谱质谱联用法分析结果表明,熏马肠挥发性风味物质主要含55种化合物,有酚类、醇类、烯烃类、烷烃类、脂类、醛酮类、含氮含硫及杂环化合物,其中酚类物质含量较高占提取总含量的52.66%,为熏马肠主要的风味物质。      

林芝松口蘑与红菇蜡伞子实体香气成分比较

研究采用顶空固相微萃取技术联合气质联用技术分别对松口蘑和红菇蜡伞子实体香气成分进行分析测定和比较分析,以期建立准确、快速、高效的鉴别方法。结果显示,松口蘑检测到74种香气成分,红菇蜡伞检测到72种香气成分,松口蘑相较红菇蜡伞检测到特有的香气成分14种,包括乙醛、庚醛等6种醛类,2(5H)-呋喃酮1种酮类,3-苯丙醇1种醇类,正己酸乙酯、丙位戊内酯2种酯类,萜品烯和异松油烯等4个烯烃类;红菇蜡伞相较松口蘑,检测到特有的香气成分16种,包括2-丁基-2-辛烯醛1种醛类,3-羟基-2-丁酮、甲基庚烯酮等4种酮类,丁醇等5种醇类,(1-羟基-2,4,4-三甲基戊-3-基) 2-甲基丙酸酯1种酯类,异丁酸、丁酸等3种羧酸类,邻甲酚1种酚类,乙二醇单丁醚1种醚类,N-甲基吡咯烷酮1种含氮化合物。经过主成分分析,得到红菇蜡伞中的主要特征性香气成分为:己醛、3-羟基-2-丁酮、3-辛烯酮、2-甲烯基丁内酯、异戊酸;松口蘑中为:异戊醛、庚醛、壬醛、2,5,2-三甲基吡嗪、2,6,2-三甲基吡嗪。同时对松口蘑与红菇蜡伞干品挥发性香气成分相对含量对比发现,松口蘑主要香气成分含量关系为醛类烯烃类醇类酯类,红菇蜡伞主要香气成分含量关系为醛类醇类烯烃类酯类。通过松口蘑与红菇蜡伞子实体干品香气成分的比较分析可为市售的2种产品的快速检验鉴别奠定理论基础。     

基于GC/MS结合多元统计学筛选爆珠香精中香味标志物

目的：筛选出爆珠香精质量控制用的特征香味组分标志物。方法：采用气相色谱—质谱法（GC/MS）对爆珠香精中挥发性及半挥发性化合物进行检测,建立目标样品色谱指纹图谱,并对组分数据进行主成分分析（PCA）和正交偏最小二乘法—判别分析（OPLS-DA）。结果：GC/MS共鉴定出27种挥发性、半挥发性物质,包含柠檬烯、丁香酚、茴香脑、薄荷醇等香味化合物以及辛癸酸甘油混合酯壁材物质;优选条件下的仪器精密度、日内精密度和日间精密度分别为0.56%～9.94%,3.07%～9.81%,2.81%～11.95%,结合ChemPattern软件近邻算法对图谱数据进行对齐,建立了爆珠香精样品的GC/MS指纹图谱;PCA分析对正常与模拟状态下爆珠香精样品区分不明显,但基于OPLS-DA分析发现共有4种化合物被鉴定为特征标志物（变量重要性投影值＞1,P＜0.05）,分别为柠檬烯、辛酸甲酯、癸酸甲酯和丁香酚,该系列特征物质可反映爆珠香精果香香韵的特点。结论：使用GC/MS采集样品指纹图谱,结合OPLS-DA分析手段,能够有效筛选出爆珠香精特征香味的标志物,为客观评价爆珠香精质量提供参考。     

Occurrence and survival of Campylobacter spp. in dairy matrices investigated by viability qPCR

The aim of this study was to investigate the survival of Campylobacter jejuni in dairy matrices by viability qPCR. Survival in UHT milk was examined first and the cheese outbreak strain, C. jejuni 11 218 showed enhanced tendency to become viable but nonculturable (VBNC). It survived for long at different pH values, in raw and fermented milk and cheese. Viability qPCR was also used to examine the occurrence of viable Campylobacter spp. in raw milk, detecting the bacteria in 40.9% of 25 mL samples negative on culture. Results showed that viability qPCR is valuable in estimating Campylobacter risk in dairy products.     

顶空固相微萃取气质联用分析香葱挥发性风味成分

采用顶空固相微萃取气质联用分析检测了香葱的挥发性风味成分,共检测到30种化合物,占总峰面积的98.18%。主要成分是二丙基二硫醚(31.94%)、二丙基三硫醚(16.4%)、1-丙硫醇(11.27%)、二甲基硫醚(10.36%)、甲基-2-丙烯基二硫(6.11%)、1-丙烯-1-甲基硫醇(3.49%),占总成分的79.57%。