马铃薯对面团及馒头品质的影响

针对马铃薯主食化品种适用性问题,选取5个品质差异较大的马铃薯样品,蒸熟制成泥后与小麦粉搭配,制作马铃薯馒头。对马铃薯馒头分别进行了感官评价和仪器分析,探究了马铃薯对面团品质的影响规律。结果表明,添加30%马铃薯泥的混合面团筋力减弱,加工性能略有下降,但具有良好的持气能力和产气能力,发酵性能良好;不同品种的马铃薯对混合面团的流变学特性及所制作的马铃薯馒头的品质影响存在较大差异,其中马铃薯1和马铃薯5较适合用于加工馒头。     

Nutritional and sensory characteristics of “early” potato cultivars under organic and conventional cultivation systems

Potato production in several Mediterranean countries is focused on the “early” crop type, and is generally associated with intensive applications of farming inputs. Recently, the enhanced interest for environmentally-sustainable production systems has led to a major expansion in the organic farming sector. Due to the lack of data in the literature about the qualitative traits of organic “early” potato, we studied some nutritional and sensory characteristics of three cultivars (Arinda, Ditta and Nicola) grown either organically or conventionally. Overall, the organic farming allowed to obtain a product with a higher nutritional value due to higher total phenolic and lower nitrate content, and better sensory performance after frying (strong taste and crisp flesh). Moreover, the lower amount of soluble sugars and higher level of dry matter under organic farming is noticeable for the possible use of “early” potato for frying. Our findings also indicate as the cultivar choice is a key aspect determining the overall quality of the organic tuber.     

Physico‐chemical and sensory attributes in conjunction with multivariate analysis of two potato (Solanum tuberosum L.) cultivars after 90 days of storage: an exploratory authentication study

Two cultivars of potato (Spunta and Agria), were studied in terms of their physico‐chemical and sensory characteristics. These cultivars were cultivated in three geographical regions of Greece (Macedonia, North Greece; Thessaly, Central Greece; Peloponnese, South Greece) and were stored for 90 days after harvesting. The physico‐chemical characteristics of the tubers determined, were pH, total acidity, firmness, dry matter and content in Ν, in Κ, P, Cu, Mn, Zn and Fe. The sensory characteristics measured for raw tubers of potato after storage, were skin colour, skin brightness, internal colour, surface roughness, odour intensity, moistness, surface wrinkling and stains while the sensory characteristics measured for the boiled tubers of potato were odour intensity, moistness, special taste, sweet taste, aftertaste persistence, metal taste, pastiness, mastication, flavour intensity, elasticity and overall acceptability. The application of multivariate analysis (principal component analysis, cluster analysis and discriminant analysis), revealed a variety of relations between the various parameters and resulted in satisfactory grouping either per geographical region or per cultivar.     

马铃薯全粉对面条品质影响的主成分分析研究

为了探讨马铃薯全粉对面条品质的影响,通过测定添加不同比例马铃薯全粉的面筋特性、蒸煮特性、质构特性和感官评价,并结合主成分分析进行综合评价。结果表明:随着马铃薯全粉添加量的增加,面条色泽呈暗红趋势变化,其面筋含量逐渐降低;面条的蒸煮特性、质构特性及感官品质呈现先增加后降低的趋势,说明适量添加马铃薯全粉可以在一定程度上提高面条的食用品质。应用主成分分析法对不同马铃薯全粉添加量的面条进行研究,确定了反映面条品质的3个主成分因子,3个主成分的累积贡献率达到88.35%。为进一步开发高含量马铃薯全粉面条提供数据支撑。     

西北旱区不同品种马铃薯薯饼加工品质特性分析

为研究不同品种马铃薯与薯饼品质特性之间的关系,以适宜西北旱区栽培的13个马铃薯鲜薯为原料制备马铃薯薯饼,并对薯饼的感官和TPA进行了分析和比较,结果表明,不同马铃薯品种对加工薯饼的品质特性具有显著影响(p<0.05),不同品种马铃薯淀粉含量、蛋白质含量与马铃薯薯饼的硬度、弹性、胶着性及咀嚼性呈极显著正相关(p<0.01),而不同马铃薯品种淀粉含量、粗蛋白含量与马铃薯薯饼色泽无显著相关性(p>0.05);综合评价感官和TPA,供试的13个品种中,陇薯7号、陇薯8号、中薯18号和新品系LY08104-12的表现较好,制得的马铃薯薯饼感官品质较好,硬度适中,口感酥软,质构品质也较优。该结论可为不同马铃薯品种在薯制品加工适宜性方面提供一定的理论参考。     

Relationship among the carotenoid content, dry matter content and sensory attributes of sweet potato

The sensory characteristics of biofortified sweet potato in Africa were explored over a wide range of carotenoid (0.4-72.5 μg/g fresh weight) and dry matter contents (26.8-39.4%). The logarithm of the total carotenoid content was correlated with the dry matter content (declining by 1.2% with each doubling of the carotenoid content) and a wide range of sensory characteristics that involve visual, odour, taste and textural characteristics. Multiple linear regression models were developed. The logarithmic relationship of colour to the carotenoid concentration means that those varieties with a relatively low carotenoid content may appear to be of similar intensity to those with a much higher and hence nutritionally beneficial carotenoid content.     

Optimisation of processing variables in the preparation of sweet potato chips using response surface methodology

Models capable of predicting the product quality of sweet potato chips have been developed using response surface methodology and used to determine the optimum processing conditions. Moisture loss, oil uptake, crispness (measured using a bending-snapping test in the TA.XT2 Texture Analyser), and sensory attributes such as colour, flavour, and texture were used to assess the product quality in the preparation of sweet potato chips. The optimum conditions which were attained for maximum moisture loss (11.65% on wet basis), minimum oil uptake (2.57%), crispness (794.37 g), colour score (7), flavour score (7) and texture score (7) were: frying temperature, 174.7 °C; salt concentration, 0.45%; citric acid concentration, 0.37%; potassium metabisulphite concentration, 0.65%; and frying time, 26 s.     

Potential impacts of bioprocessing of sweet potato: Review

Sweet potato (Ipomoea batatas L.) is among the major food crops in the world and is cultivated in all tropical and subtropical regions particularly in Asia, Africa, and the Pacific. Asia and Africa regions account for 95% of the world's production. Among the root and tuber crops grown in the world, sweet potato ranks second after cassava. In previous decades, sweet potato represented food and feed security, now it offers income generation possibilities, through bioprocessing products. Bioprocessing of sweet potato offers novel opportunities to commercialize this crop by developing a number of functional foods and beverages such as sour starch, lacto-pickle, lacto-juice, soy sauce, acidophilus milk, sweet potato curd and yogurt, and alcoholic drinks through either solid state or submerged fermentation. Sweet potato tops, especially leaves are preserved as hay or silage. Sweet potato flour and bagassae are used as substrates for production of microbial protein, enzymes, organic acids, monosodium glutamate, chitosan, etc. Additionally, sweet potato is a promising candidate for production of bioethanol. This review deals with the development of various products from sweet potato by application of bioprocessing technology. To the best of our knowledge, there is no review paper on the potential impacts of the sweet potato bioprocessing.     

马铃薯泥对面团及面包品质的影响

为提高马铃薯的利用率,丰富主食面包的种类,选取5个不同品种的马铃薯样品,蒸熟后制成马铃薯泥,按30%的比例添加到面包粉中制作面包。通过分析混合面团的粉质、拉伸特性及发酵性能,研究添加马铃薯泥对混合面团流变学特性的影响;通过对马铃薯泥面包进行感官评价和仪器分析,探索添加马铃薯泥对面包品质的影响。结果表明,添加马铃薯泥后,混合面团筋力减弱,加工性能略有下降,但具有良好的持气能力和产气能力,发酵性能良好;添加马铃薯泥后所制面包体积变大,且不易老化,其中加入5号马铃薯样品的面包感官评价总分最高,面包切片亮度高于对照样品,且粗气孔体积得到改善。综合考虑面包的感官和物理特性,添加5号马铃薯样品做出的面包品质最好。     

响应面法优化甘薯泥馒头加工工艺

以20%甘薯泥和小麦粉为原料,研究压面次数、醒发时间、醒发温度对甘薯泥馒头品质的影响规律。在单因素实验基础上,选取感官评价为考察指标,利用响应面分析法对甘薯泥馒头加工工艺进行优化。结果表明,甘薯泥馒头的最佳工艺为:压面次数14次,醒发时间18 min,醒发温度33℃。所制作的甘薯泥馒头品质较好,具有特殊的甘薯香味。     

魔芋葡甘聚糖对紫薯猪肉丸储藏品质的影响

目的 探究魔芋葡甘聚糖(konjac glucomannan, KGM)对紫薯猪肉丸储藏品质的影响。方法 添加10%质量分数的紫薯全粉,同时利用KGM凝胶作为脂肪替代品制作紫薯肉丸,通过感官评定和测定理化指标分析猪肉丸在储藏过程中的品质变化,探究KGM对猪肉丸的储藏特性的影响。结果 通过权重法配方优化确定以6%KGM凝胶替代50%脂肪的紫薯猪肉丸(KGM6-50)综合评分最高;与无紫薯添加组相比,KGM6-50样品在储藏过程中冻融析水率显著降低,肉丸的质构品质劣变减缓,pH和蒸煮损失无显著变化;相较于添加紫薯全粉的全脂肉丸,KGM6-50样品冻融析水率略有提高而蒸煮损失降低;在储藏时间30 d以内时,肉丸的过氧化值较低且品质变化较小,为最佳食用期。结论 KGM凝胶可有效改善紫薯猪肉丸品质,且可抑制肉丸在储藏过程中的品质劣变,结果可为肉制品的品质改良和储藏品控提供参考依据。     

不同品种马铃薯对马铃薯-小麦复合馒头品质特性的影响

本文以22个品种的新鲜马铃薯为原料制备马铃薯全粉,并对马铃薯全粉的基本成分进行了分析和比较;然后以22个不同品种的马铃薯全粉为原料制作马铃薯-小麦复合馒头(马铃薯全粉:小麦粉=3:7),并对其比体积、高径比、气孔结构和质构特性进行了分析和比较。结果表明,不同品种马铃薯-小麦复合馒头的比体积、高径比、气孔特性和质构特性存在显著差异性(p0.05)。高径比和比体积均较高的品种是紫花白、夏波蒂、陇薯6号、陇薯7号、中薯2号;气孔密度和气孔表面积分率都较高的品种是一点红、青薯9号、大西洋;硬度和咀嚼性都较好的品种是一点红、费乌瑞它、青薯6号、青薯9号、大西洋。综合考虑馒头的感官和物理特性,一点红、青薯9号和大西洋3个品种比较适合替代小麦粉,制得体积较为理想、硬度较低、气孔结构较好的馒头。     

红薯浆的酶解与发酵制备红薯全汁酸奶的研究

以红薯浆为原料,通过添加纤维素酶,α-淀粉酶对其进行水解得到红薯浆全汁。结合单因素和正交实验,确定了最佳酶解工艺,即纤维素酶添加量0.7%、酶解时间3.0h、加水量与薯液比5:1,pH6.5,在此酶解工艺条件下,出汁率可达42%。以红薯乳全汁为原料,接种乳酸菌对其进行发酵制备红薯乳全汁酸奶;以产品酸度、黏度和持水力等理化指标并结合感官评价指标为考察依据,通过正交实验确定了最佳发酵工艺为:红薯浆与脱脂乳比例5:5,菌种接种量5%、发酵温度37℃、蔗糖添加量4%。在此条件下所得红薯全汁酸奶理化和感官指标均为最佳。     

不同类型甘薯最佳烹饪方式评价

本研究通过评价甘薯不同食用方式下食味品质,明确不同鲜食品种的最佳食用方式及其与各品质指标的相关性。以干率、蛋白质、淀粉含量均较低的两个品种冀粉2号、烟薯25和干率、淀粉、蛋白质含量均较高的两个品种冀薯8号、冀元1号为材料,选择2种烹饪方式（烤制和蒸制）对薯块进行处理,采用感官评价、TPA测试、气相色谱-质谱联用（GC-MC）等方式对烤制和蒸制甘薯的口感、质构和香味成分进行测定分析。结果表明：薯块硬度、弹性、粘附性、咀嚼性、胶粘性在两种食用方式之间差异较大。相关性分析：干率与烤和蒸薯的内聚性、咀嚼性呈正相关;与淀粉、还原糖、可溶性糖呈负相关;蛋白质与烤和蒸薯的硬度、内聚性、胶粘性、咀嚼性呈正相关;与淀粉、还原糖、可溶性糖、烤和蒸薯的回复性呈负相关;淀粉与还原糖、可溶性糖、烤和蒸薯的弹性、回复性呈正相关;烤和蒸薯的咀嚼性、胶粘性呈负相关;还原糖与可溶性糖、烤和蒸薯的弹性呈正相关;与烤和蒸薯的硬度、咀嚼性 、胶粘性呈负相关;营养特性与质地指标具有一定的相关性。薯块烤制和蒸制共检测出49种香气物质,冀粉2号、冀薯8号香味物质烤制比蒸制分别多11、8种,冀元1号、烟薯25香味物质烤制比蒸制分别少3、1种;感官评价得出冀粉2号、烟薯25烤制口感比蒸制口感好;冀薯8号、冀元1号蒸制口感比烤制好。综合得出：干率、蛋白质含、淀粉含量均较低品种冀粉2号、烟薯25适合烤制;干率、蛋白质、淀粉含量均较高品种冀薯8号、冀元1号适合蒸制。     

马铃薯基质对其挂面品质的影响研究

由马铃薯干粉制作得马铃薯面条,成本较高,探讨降低马铃薯面条成本的方法。采用将马铃薯薯块研磨成浆或蒸后研磨成泥后,利用马铃薯薯块中的水分,加入到小麦粉中制作马铃薯面条,以干粉为对照,探讨马铃薯生浆或熟泥代替干粉的可能性。结果显示：采用马铃薯熟泥制作的干面条较白,L*值为78.99±0.42,断裂距离为28.7±1.8 mm,断裂强度为22.4±2.6 g,煮后面条的坚实度为823.7±11.7 g,高于或不低于干粉挂面的各项得分。感官评价的适口性、韧性、总分也高于马铃薯干粉挂面;采用马铃薯生浆制作的干面条颜色偏暗,L*值为75.20±0.76,煮后口感较硬,弹性不足,口感稍差。综合考虑,可以用马铃薯熟泥代替马铃薯干粉进行马铃薯-小麦粉混合粉挂面生产,有利于减少工序、节约能源,降低生产成本。     

Biofortification of sweet potato for food and nutrition security in South Africa

South Africa has a diverse population, with some pockets of society being in a first world setup and other pockets in a third world impoverished setup. Food provision in impoverished societies is particularly crucial. Sweet potato (Ipomoea batatas (L.) Lam.) is a hardy crop and prominent in ensuring household food security; through its rich supply of energy, high yield potential and market value. In addition, orange-fleshed cultivars in particular are prominent in combating vitamin A deficiency due to high content of naturally bio-available β-carotene. This paper reviews interventions with regard to biofortification of sweet potato in South Africa towards addressing food and nutrition security. The focus was on the development of biofortified (high β-carotene content) cultivars and screening procedures for desired varietal traits; assessment of β-carotene, anti-oxidant and mineral content and the processing potential of orange-fleshed cultivars. Efficacy of orange fleshed sweet potato to improve vitamin A status was shown and positive effects of household production of orange-fleshed sweet potato, in conjunction with other β-carotene rich vegetables, on dietary intake, vitamin A status and food security were recorded. Dissemination efforts were initially focused on home gardens, which gradually expanded to subsistence production and enterprises. During 2014/15, over 1 million cuttings were disseminated and 5 to 40 small-scale commercial farmers in six provinces planted 0.25 to 1 ha of orange-fleshed sweet potato as means for income generation. In order to exploit the nutritional benefits of sweet potato and its potential to reduce vitamin A malnutrition and food insecurity, it is recommended that policy makers set directives to incorporate orange-fleshed sweet potato in government programs related to health, rural development, social development and agricultural production. There is a great need for investment in promotion of orange-fleshed sweet potato, particularly to consumers and retailers. Private–public partnerships and investment by private companies will be crucial for upscaling the impact of orange-fleshed sweet potato on food and nutrition security.