Canadian consumer acceptance of gene-edited versus genetically modified potatoes: A choice experiment approach

In 2016, second-generation genetically modified (GM) potatoes were approved for production and sale in Canada. In this study, we analyze how consumer acceptance of GM potatoes may be affected by various factors, including the trait introduced (i.e., the product benefits), the type of breeding technology used, and the developer of the potato using any technology. We conduct an online survey and use a stated choice experiment to collect data on consumer acceptance of GM and other potatoes in Canada. Random utility models are used to analyze the economic value consumers place on the various attributes of the potatoes. Our results show that consumers are willing to pay more for a health attribute (reduced acrylamide produced when potatoes are fried) and an environmental attribute. Respondents in general need to face discounted prices to buy potatoes created by either gene editing or GM (either transgenic or cisgenic/intragenic) technologies. However, consumers are in general more accepting of the gene editing technology than the GM technologies. Our results also show that government is the most preferred developer of the potatoes, regardless of technology. Results from this study can help guide public and private management of the introduction of new foods when the products are developed with unpopular technologies.     

基于DEA-Tobit模型的马铃薯生产效率分析——以甘肃省定西市为例

随着社会的进步和农村经济的发展,农业生产效率已成为制约农民收入、造成农村落后的关键因素。中国是马铃薯的生产大国,其生产效率的提高对我国马铃薯产业的持续发展和保障我国的粮食安全有着很重要的意义。研究基于2014年对甘肃省定西市样本农户马铃薯种植的调查数据,采用DEA模型测算农户种植马铃薯的生产效率,并利用Tobit模型对影响马铃薯生产效率的因素进行分析。研究表明:农户生产马铃薯的综合技术效率较低,规模效率成为制约其生产效率提升的瓶颈;家庭纯收入、马铃薯的种植比例和引进新品种3个变量在0.01水平下对生产效率的影响达到显著;户主的年纪在0.05水平下对生产效率的影响达到显著;马铃薯的收购价格、农户是否参加合作社和种植培训、离农贸市场距离与马铃薯的生产效率间存在不显著的正相关关系。基于以上调研提出了鼓励土地流转、提高生产技术水平、加大农民生产技能培训力度、多方面增加农民收入和合理布局农产品贸易市场等政策性建议。     

基于高光谱曲线的马铃薯与其他主要作物光谱差异性分析

[目的]文章以马铃薯关键生长期——结薯期为测量时点,以马铃薯和玉米、大豆、水稻为研究对象,开展高光谱曲线特征差异性研究。[方法]为更好地描述马铃薯与其他作物的光谱差异,创建高光谱反射率差异性指数、高光谱一阶导数差异性指数、高光谱红边幅值差异性指数、高光谱曲率差异性指数及高光谱植被指数差异性指数。[结果](1)马铃薯与玉米、大豆、水稻3种作物光谱曲线具有明显差异,马铃薯与玉米的反射率值在480nm附近蓝色波段位置差异最显著,差异性指数值为67.866%,与大豆、水稻的最大差异性指数值分别为49.068%、57.559%,均位于550nm附近绿色波峰位置;(2)作物光谱曲线经一阶导数变换运算,马铃薯与其他作物间的光谱差异被显著放大,在近红外波段放大程度最显著;(3)马铃薯与玉米、大豆、水稻高光谱曲率差异性指数最大值均位于波长750nm附近,差异性指数值分别为78.365%、63.471%、80.882%;(4)常用植被指数中,比值植被指数、增强型植被指数可显著区分马铃薯与玉米、大豆、水稻。[结论]差异性分析结果为农作物空间分布遥感识别提供了技术支撑。     

Slicing,Dicing, Spicing,and Pricing: Factors Influencing Purchase and Consumption of Fresh Potatoes

To better understand potential reasons for a North American decline in fresh potato consumption, a region-wide survey (n = 1009) was undertaken in eastern Canada. Results were examined comparing high- and low-frequency potato users on a variety of factors, including beliefs, attitudes, barriers, needs, and satisfaction with potatoes. Respondents indicated positive perceptions pertaining to potato nutrition, taste, preparation, and overall enjoyment. Multiple logistic regression analysis suggested two variables—age and the perceived importance of potatoes for the everyday meal—were strong predictors of high versus low frequency of potato consumption. Respondents judged the ability to see the potato in the package, potato firmness, and locally produced as point-of-purchase characteristics particularly important when buying fresh potatoes. However, respondents also indicated that their needs were not fully met and expressed relatively low levels of satisfaction when purchasing potatoes. Based on the results, suggestions are provided for improving the marketing of fresh potatoes.     

木薯变性淀粉在食品工业中的应用概述

木薯变性淀粉作为食品添加剂应用在食品工业中有其独特的优势,随着人们对木薯变性淀粉的认知,其使用范围逐步得到拓展,使用量逐渐增大。文章阐述了食品工业中常用的几种淀粉基食品添加剂及其应用发展趋势,并结合笔者多年从事变性淀粉技术研发的经验,着重介绍了几种木薯变性淀粉的性能,以及其在肉制品、面制品等行业的应用情况。     

一种用在建筑胶水的变性淀粉制备方法

采用半干法工艺反应引入两种阴离子基团制备羧甲基淀粉,考察氧化剂、氧化反应温度、醚化剂、醚化反应时间、催化剂等因素对反应的影响。结果表明：采用半干法制备较佳的反应工艺为：醚化剂用量2A～4A,氧化剂用量0.6～1.0%,反应时间3h,温度为30℃,催化剂A＋B,交联剂0.2%,增塑剂0.3%。所制备的双阴离子羧甲基淀粉具有较高的取代度,冷水可溶,增稠好,粘结力高等特性,在建材领域上具有广泛的应用。     

Effect of deep‐fat frying of potato chips and chicken on the quality of soybean oil

The type of products may affect the quality of oil during deep‐fat frying. The quality changes in pure soybean oil during frying of potato chips and chicken drumsticks were evaluated and compared. The oil was subjected to continuous frying at 180°C for a period of 315 min. The parameters used to assess the oil quality were peroxide value (PV), iodine value (IV), free fatty acids (FFA), refractive index (RI) and colour. The percentage of oil absorbed by the two products was determined. The oil was also assessed visually for any change in colour, viscosity, turbidity, flavour and deposit. Results showed that, for both products, PV, IV, FFA, RI and colour changed significantly with time (P < 0.05). Potato absorbed oil during frying (6.9%), whereas chicken released fat into the frying medium (2.4%). When the rates of change of the various parameters in the oils were compared for the two products, significant differences (P < 0.05) were noted for PV and colour only. The oil used during the frying of chicken appeared visually to be at a more advanced stage of deterioration.     

山东省马铃薯种植收益影响因素分析

以山东省为例,运用主成分回归分析和灰色关联分析对山东省马铃薯种植收益的影响因素进行分析。结果发现,影响马铃薯种植收益最显著的因素是马铃薯售价,另外,人工成本、种子费用、租赁作业费和化肥费用对马铃薯收益的影响也较大。其中种子费、化肥费、主产品售价、间接成本正向影响马铃薯种植收益,农药费、租赁作业费、人工成本以及土地成本负向影响马铃薯收益。据此,提出降低马铃薯种植成本、提高收益的对策建议。     

羧甲基淀粉钠中的氯化物含量的定量分析

采用分光光度法对羧甲基淀粉钠中氯化物含量定量分析,研究了测量波长及反应时间对吸光值的影响。在检测波长342nm、反应时间为40min时定量测定羧甲基淀粉钠中氯化物含量,并与国标法进行了对比。     

基于多源遥感数据的马铃薯收入保险应用研究

目的 研究面向创新型农业保险业务中缺少及时准确的第三方作物产量结果用于灾损理赔的问题。引入多源卫星遥感测产技术,识别测产关键因子,构建产量模型。方法 文章运用多元线性回归分析方法,选取山西省马铃薯主产县岚县为研究区,计算基于Sentinel2影像的植被指数,结合气象卫星数据与实测单产数据,筛选关键因子,建立马铃薯单产遥感测产经验模型。结果 采用GF-2影像分割与Sentinel2长势时序识别岚县马铃薯种植面积为8 477.65hm²,精度检验Kappa值为0.72。保险公司岚县承保马铃薯面积2 476.37hm²,承保覆盖率为29.21%。测产结果显示,马铃薯单产与区域关键期地表温度参数相关性较好,岚县遥感测产获得平均单产为13.76 t/hm²,实地测产获得平均单产为14.06 t/hm²,误差百分比为2.13%,分乡镇平均误差百分比为22.97%,基本满足理赔业务需求。在2018年保险期结束后一周内,保险公司启动快速赔付,支付赔款125.29万元,赔付率48.46%。结论 遥感测产具有大范围、时效性好、可靠性高等特点,能够迅速为创新型保险产品提供测产理赔结果,提高理赔效率,保障农民收入。