二次发酵法制作马铃薯馒头的工艺优化

采用二次发酵法,以产品感官品质评定得分为依据,研究了马铃薯馒头制作过程中的几个关键工艺条件对产品品质的影响。采用四因素三水平正交实验对关键工艺条件进行分析,从而确定马铃薯馒头的最佳制作工艺条件为:马铃薯粉与小麦粉的添加量之比为2∶8,酵母粉的添加量为0.9%,第一次发酵时间为90 min,第二次发酵时间为20 min。     

小麦粉中阿拉伯木聚糖含量与小麦籽粒之间的关系

本文研究了面粉中阿拉伯木聚糖（简写AX）含量与小麦籽粒特性之间的关系,研究结果表明：AX含量与硬度（r=0.049）、水分（r=0.048）呈微弱正相关;与容重呈显著负相关（r=-0.215）,因为AX主要存在于小麦籽粒面筋蛋白和淀粉之间,当它们之间的AX多时,面筋蛋白和淀粉的量就会减少,容重就会减少;面粉中的AX与不完善粒（r=0.146）、出粉率（r=0.155）呈正相关,因为在小麦籽粒中,麸皮中AX含量占小麦籽粒的30%左右,当出粉率增加,会使一小部分的麸星进入面粉,从而使面粉中的AX增加。     

AX与面粉品之间的关系

本采用不同品种的小麦为原料,首先通过测定小麦籽粒和面粉的品质特性及其阿拉伯木聚糖(AX)含量,对AX含量与小麦粉品质间的关系进行探讨。主要研究结果如下:(1)对小麦品质指标的测定,结果显示不同品种的小麦籽粒间存在较大的差异。面粉中AX含量与蛋白(r=0.27)、麸星含量(r=-0.16)存在存在一定的正相关,而AX含量与白度和降落数值存在微弱的负相关,面粉中AX中含量与面粉的吸水率、面团的形成时间、面团的稳定时间和弱化度呈弱相关性,相关系数分别是r=-0.34、r=0.27和r=-0.09;(2)不同的面粉中AX含量与峰值粘度呈显著负相关,与最低粘度、最终粘度呈弱负相关,当面粉中AX含量增加时,峰值粘度、最低粘度、最终粘度都会降低;峰值粘度与最低粘度、最终粘度呈显著正相关。     

Effects of selected antioxidants on physical and sensory characteristics of yeast bread containing flaxseed meal

Flaxseed has been identified as a potential functional food because of its high content of phytochemicals, alpha‐linolenic (α‐linolenic) acid and lignans. Flaxseed can be used in baked goods because of its minimal loss of α‐linolenic acid. Alpha‐linolenic acid is susceptible to oxidation and the development of off‐aromas and flavours in the food. The focus of this study was to determine the effectiveness of both synthetic and natural antioxidants that were incorporated into a yeast bread that contained 15% flaxseed as a partial replacement for bread flour. The study evaluated the effectiveness of the antioxidants on the physical and sensory characteristics of the bread. Physical properties, such as per cent moisture and loaf volume, were not affected (P > 0.05) by the antioxidants, but ascorbic acid, butylated hydroxytoluene and butylated hydroxyanisole, independently, had a softening affect (P < 0.05) on crumb firmness. Sensory analysis indicated significant (P < 0.05) changes in aroma, grainy taste, aftertaste and moistness in all bread samples regardless of antioxidant, however, only ascorbic acid was rated as effective in maintaining a softer (P < 0.05) crumb.     

大豆蛋白在焙烤食品中的应用

我国大豆制品质量飞速提升,但大豆蛋白于烘烤食品中的应用仍存在诸多不足之处。本文探讨大豆蛋白在焙烤食品中的应用,并提出实用性应用措施,为烘烤食品中大豆蛋白应用提供参考依据。     

Sensory evaluation and consumer acceptance of carbohydrate-based fat replacers in biscuits

The effect of three different carbohydrate-based fat substitutes in a baking powder biscuit was studied. The various fat replacers were substituted for fat in the biscuit formula at a rate of 33%, 66% and 100%. The biscuit variations were assessed by objective and sensory measurements. Comparable objective and sensory results indicated that crust colour was lightened significantly with increased use of the individual fat substitute. Tenderness decreased as substitute use increased when biscuits were rated by the sensory panel, but opposite results were obtained by the texture analyser. Objective analysis indicated that an increase in use of the fat substitute produced a moister biscuit, which was in agreement with the sensory panel. Consumer location testing rated the biscuits as moderately acceptable, but data did indicate a willingness for a product of this type to become available in the marketplace. The overall results do indicate that a fat substitute can be a viable additive in the basic biscuit, but there is a maximum at which the substitute can be used for fat and still produce an acceptable product.     

South African consumers' opinions and consumption of soy and soy products

Interest in soy foods has increased with consumer awareness of its health benefits, especially with soy‐related ingredients being utilized as one of the major sources of high‐protein fortification. The aim of the present study was to assess South African (SA) consumers' opinion of soy and soy products through different statements on consumption, taste, protein value and healthiness. The respondents (n = 3001) for this randomized cross‐sectional study were randomly selected from metropolitan and rural areas in South Africa. Trained fieldworkers administered questionnaires by conducting face‐to‐face interviews. Fourteen statements from four sections of the questionnaire (consisting of 17 food‐related topics in total), probing information on consumers' opinion on soy and soy products, were used. Data on 81% of the respondents (n = 2437), who had heard of soy before, were used for statistical analyses. The data were weighted to be representative of the total SA population based on gender, age and race. No practically significant differences among metropolitan and rural respondents' opinion, gender or age variables regarding any statement were found. A practically significant higher percentage (>60%) of respondents in the total population and within all race groups were positive about soy and agreed that soy is a good source of protein, has many health benefits, associated soy with meat substitutes, were aware of a number of meat substitutes and agreed that soy can replace meat in their diet. Medium to large practically significant differences were found between racial groups regarding certain statements. More Blacks and Indians (76% and 68% respectively) than Whites (25%) use soy. Almost two‐thirds of Indians (65%) and Blacks (64%) eat or drink soy products, compared with only 22% for Whites, indicating that the potential target market for soy products should be chosen accordingly. Higher percentages of Blacks than Whites also indicated that they liked the taste of soy, would use more soy if it was readily available and if a bigger product range existed and would replace cow's milk with soy milk, confirming that Blacks are more positive about soy and would use even more soy if a bigger range of soy products were available. The findings from the current study indicated that more than 70% of SA consumers believe that soy has many health benefits and more than 60% already use soy. Insight gained from this first study of its kind in SA provided valuable information to developers and marketers, and signified that consumer segmentation should be taken into consideration to focus on developing more acceptable soy products that appeal to these consumer segments that are more positive towards the taste of soy and might consume soy regularly. Within the discipline of Consumer Science, efforts to inform consumers about the advantages of soy in terms of its health benefits, and to support it in terms of a greater availability of more acceptable soy products at reasonable prices, would support the ideal of informed, responsible buying decisions across all socio‐economic groups.     

小麦胚的提取及其应用

介绍了小麦胚存在面粉中的不利原因，并从营养方面阐述了提取小麦胚的益处，还从小麦胚的性状和制粉工艺角度分析讨论了影响提取小麦胚的因素以及解决办法。     

The synergistic effects of maltodextrin and high‐fructose corn sweetener 90 in a fat‐reduced muffin

Low‐fat muffins were prepared using as fat substitutes a combination of maltodextrin and high‐fructose corn sweetener 90 (HFCS‐90), which replaced sucrose at a rate of 25%, 50%, 75% and 100%. The focus of the investigation was to determine the synergistic effects of these two ingredients on the physical properties in a low‐fat muffin. Results indicated that maltodextrin and HFCS‐90 were effective in maintaining moisture and water activity (a_w) levels similar (P > 0.05) to the full‐fat muffin. Texture profiles indicated that the low‐fat variations were firmer (P < 0.05) than the full‐fat counterpart. Increased levels of HFCS‐90 had a significant effect (P < 0.05) on crust and crumb darkening. Maltodextrin alone significantly (P < 0.05) impeded the staling rate during storage. However, when maltodextrin was combined with increased levels of HFCS‐90, the staling rate accelerated. The two ingredients were found to be effective in maintaining product quality, but HFCS‐90 could only be used up to a 50% replacement before any adverse effects in product quality were observed.     

Production and sensory characteristics of flavoured soymilk samples

The sensory quality characteristics of four flavoured soymilk samples including vanilla, banana, coffee and chocolate were evaluated at varying concentrations of the flavour. This was done to establish the most acceptable flavour and desired concentration for commercial production of soymilk and also to facilitate increased consumption of soymilk for improved nutrition. Hot extraction of the milk from blanched soybeans was achieved by blending in hot water and sieving through muslin cloth. Different concentration levels of the flavours being assessed, namely chocolate, coffee, vanilla and banana, were added. Consumer preference for the various samples was assessed using a nine‐point hedonic scale. Addition of flavours was found to improve the sensory characteristics and consumer preference of soymilk. Colour, taste, aroma, mouthfeel and hence overall acceptability of the soymilk samples were improved significantly by the addition of vanilla, banana, coffee and chocolate flavours. The maximum concentrations of the individual flavours for optimal sensory impact were established. Based on the results, the following flavour concentrations are recommended per 100 ml of soymilk: 0.03% vanilla, 0.01% banana, 1.5% coffee and 4% chocolate.     

Market testing of a major cassava flour product in the Accra metropolitan area*

The current study analyses consumer judgements about some existing as well as newly introduced brands of a processed cassava food product (fufu flour) by means of market testing. Except for colour, the respondents’ evaluation of the sensory attributes of the various fufu flours that they have consumed did not have much significant differences. Also, no significant differences in sensory attributes were identified when the fufu flour brands were compared with traditional fufu, except for hand‐feel, smoothness and elasticity. In addition, no significant differences were observed in the prices of the various fufu flour brands in comparison with the equivalent price of traditional fufu. The study finds diversification of the marketing outlet for fufu flour as a major factor that could contribute to improving the awareness of the product.     

不同系统粉黏度特性比较研究

小麦系统粉因为出粉部位不同导致不同系统粉的品质具有一定的差异。RVA粘度特性主要反映了小麦粉淀粉的糊化特性,还可以从一定程度上反映样品的α-淀粉酶活性,所以对面粉品质影响较大。通过实验表明：系统粉RVA糊化温度的顺序为2M〉总粉〉1B〉2B〉1M;峰值粘度、最低粘度、最终粘度和稀懈值的顺序1B〉2B〉1M〉总粉〉2M;回生值的顺序为：1B〉1M〉2B〉总粉〉2M。     

小麦胚芽的综合利用

本文对麦胚油、谷胱甘肽、天然维生素E、麦胚凝集素的提取和麦胚焙烤食品、蛋白饮料、豆制品等麦胚食品的开发利用进行较为全面的论述,并分析小麦胚芽资源开发利用存在的问题和应用前景。     

Consumer acceptance of fatty spreads

The effect of consumer trends on the purchase of reduced fat products in general and fatty spreads in particular are discussed. A variety of fatty spreads with fat levels ranging from 20 to 80% were assessed by cone penetration measurements and sensory assessments. The results indicated that butter had poor spreadability characteristics at 5° and 10°, while mechanically worked butter (spreadeasy butter) gave a significantly different texture profile, as measured by the Instron Model 1000. This butter type was assessed as being spreadable at 10° by the sensory panelists and by cone penetrometry. Comparable values of hardness were obtained using data obtained by cone penetrometry and texture profile analysis from the Instron. Low fat spreads (fat levels 25–39%) produced desirable spreadability characteristics using both objective and subjective methods of assessment. Sunflower oil-based spreads and very low fat spreads, i.e. ≦ 25% fat, were assessed as being soft and oily. The results overall indicated that the use of a cone penetrometer and the subsequent calculation of a yield value gave, using Haighton's seven-point scale, a good indication of spreadability characteristics.     

小麦调质方法的研究现状

小麦调制处理是制粉工艺中一道重要的工序,直接影响着面粉的加工精度与品质。本文论述了小麦调质处理的作用、理论并重点叙述了调质方法的研究现状。     

South African consumers' opinions and beliefs regarding the health benefits of soy and soy products

Studies linking diet and health and consumers' demand for health information, has led to an increasing awareness of the role of nutrition in health and disease. Interest in soy foods and an awareness of its health benefits has also increased. The objective was to assess South African (SA) consumers' opinions and beliefs regarding the health benefits of soy and soy products using different statements. This cross‐sectional study randomly selected 3001 respondents from metropolitan and rural areas in South Africa. Data of 81% of respondents (n = 2437), who had heard of soy, were used. Trained fieldworkers administered questionnaires as face‐to‐face interviews. Fifteen statements probing consumers' opinions regarding the health benefits of soy were used. The data were weighted to be representative of the total South Africa adult population (n = 18 251 000) based on gender, age, living environment and race distribution in 2000. Effect sizes were used to determine the strength of associations (practical significance), since statistical significance could be attributed to the large study population. No practically significant differences between either gender or age groups, or between rural and metropolitan respondents' opinions were found. Most respondents in the total study population (50–75%), as well as within all race groups agreed that soy has many health benefits; soy is good for you; soy lowers cholesterol; soy is good for people with a milk allergy; soy helps keep your heart healthy; soy is good for diabetes and soy is good for growing children. Medium to large practically significant differences were found between racial groups regarding some of the statements. Practically significantly more adult Black consumers believed that soy is only for people with a low‐income, and fewer that soy milk is good for people with a milk allergy than did White, Indian and Coloured consumers. Whites were relatively more positive towards the use of soy for people with a milk allergy opposed to Blacks, while Blacks were relatively more positive than Whites towards the statement that soy helps keep your bones strong. The results indicate that SA consumers held positive opinions and associate consumption of soy with several health benefits. The role of soy is seen more as being preventative than curative. It may represent a challenge to the food industry to design soy‐containing products that appeal to a broader spectrum of consumers.     

The Business of Survival: Competition and Cooperation in the Shanghai Flour Milling Industry

At the turn of the twentieth century, American and Chinese millerswere locked in a fiercely contested battle for control of China’sflour market. Imported American flour had dominated Chineseurban markets since the early 1880s, but the founding of a modernnative milling industry in 1900 had initiated a commercial warthat pitted the great flour corporations of the Pacific Coastagainst the independent mill owners near Shanghai. Althoughthe anti-American boycott of 1905 had boosted sales for Chinesemills and sparked growth in the native industry, the periodbetween 1905 and 1909 severely tested the ability of the youngindustry to survive foreign competition. A high silver/goldrate, low transpacific shipping rates, and bumper wheat harvestsin the Pacific Northwest lowered the relative cost and enhancedthe market appeal of American flour to Chinese brokers. Conversely,severe flooding in China’s wheat-producing regions forcedcurtailment or even cessation of production for some nativemills. Facing catastrophic reductions in their wheat suppliesand markets saturated with American flour, Chinese millers devisedalternative business strategies and implemented collaborativemeasures to ensure the solvency of their mills. This study examinesthe details and dynamics of the competition between native andimported flour and highlights the decisive measures Chinese mill ownersemployed to assure the survivability of the modern milling industryin China.

If there were any question . . . or doubt about the Chinesebecoming a flour-eating people to a considerable extent, thebuilding of a mill by the Fou Foong Flour Mills Co. at Shanghaiwould dispel it. It is not in the nature of things for Chinesebusinessmen to act hastily, so that the erection of this millmay be regarded as an index of the future. E. S. Rollins, 1901¹

     

小麦物理参量的应用与杂质清理

简单介绍了小麦的部分物理参量及其应用,又把混入的杂质与小麦物理个性、食用价值进行差异比较,阐述了清理原则、清理流程、清理设备和清理效率系统理论,以强化小麦加工前的净化意识,确保制粉条件实现。     

Computerized electronic temperature control system for thermal efficiency during baking in food research

A more sophisticated temperature control system than the capillary thermostat in conventional electric ovens is necessary for laboratory research on foods. The aim of the study was to develop a computerized temperature control system (CTCS) for conventional electric ovens and to determine whether the CTCS could effect comparable and consistent results in two ovens with regard to oven and product characteristics of baked products. No significant differences were found between the two ovens with regard to average oven temperature, texture and height of products. In most instances there were also no significant differences between the ovens with regard to instrumental colour measurement and moisture loss. The regression results also illustrated the effectiveness of the CTCS, i.e. that an increase in set oven temperature of 1°C has a significant effect on specific oven and product characteristics. The CTCS therefore significantly improved the reproducibility of quality characteristics of baked products. Thus, more consistent and repeatable results can be obtained to improve the reliability of consumer‐driven food research.     

麦麸品质的动态内涵与纤维食品的开发利用

麦麸和麦皮的概念不同,麦皮作为小麦籽粒结构的组成部分是个定值,麦殖是相对出粉率的变量。作者从这一观点审视,研究了二者之间的和麦麸产量,营养成分在制粉工艺中的动态变化,揭示出麦麸这一食物源对人体健康的重要性,展现了麦麸综合利用的画面和索得纤维食品的途径,从此呼唤制粉工业拓宽产品新路。