Fruits and Vegetables Freshness Categorization Using Deep Learning

The nutritional value of perishable food items, such as fruits and vegetables, depends on their freshness levels. The existing approaches solve a binary class problem by classifying a known fruitvegetable class into fresh or rotten only. We propose an automated fruits and vegetables categorization approach that first recognizes the class of object in an image and then categorizes that fruit or vegetable into one of the three categories: pure-fresh, medium-fresh, and rotten. We gathered a dataset comprising of 60K images of 11 fruits and vegetables, each is further divided into three categories of freshness, using hand-held cameras. The recognition and categorization of fruits and vegetables are performed through two deep learning models: Visual Geometry Group (VGG-16) and You Only Look Once (YOLO), and their results are compared. VGG-16 classifies fruits and vegetables and categorizes their freshness, while YOLO also localizes them within the image. Furthermore, we have developed an android based application that takes the image of the fruit or vegetable as input and returns its class label and its freshness degree. A comprehensive experimental evaluation of proposed approach demonstrates that the proposed approach can achieve a high accuracy and F1score on gathered FruitVeg Freshness dataset. The dataset is publicly available for further evaluation by the research community.     

基于LabVIEW的干燥过程果蔬内部温度测试

温度是影响果蔬干燥过程的重要参数之一。采用探针法设计了一种测试干燥过程果蔬内部温度的系统。该系统以LabVIEW为平台开发虚拟面板,实时显示图形数值温度数据并进行数据保存,有效运用Tab控件实现菜单式友好用户界面;NI9205模块采集信号经过A/D转换,经下位机NI CompactDAQ的USB总线传送至计算机,构建完整的USB数据采集过程。实际应用表明,系统能实时监测干燥过程果蔬内部的温度变化,为干燥过程果蔬内部热传递现象的研究提供有效途径。     

矿物填充保鲜膜的研制与应用

研究了利用无机矿物填料填充改性聚乙烯薄膜制备果蔬保鲜膜的方法.通过各项基本性能的测试,自制的保鲜膜完全符合果蔬保鲜包装的要求.同时,通过对几种果蔬的实际包装试验,证明该保鲜膜可以有效的抑制果蔬的呼吸强度,延缓果蔬衰老,维持良好的贮藏质量.     

Recent Food Drying R&D at Jiangnan University: An Overview

Drying of fresh produce and marine products to develop high-quality dried products cost-effectively has been the theme of extensive research carried out at the School of Food Science & Technology of Jiangnan University, Wuxi, China. Both conventional and innovative hybrid drying techniques encompassing the enhancement of drying rates and quality through utilization of modern ultrasonic and nanotechnology have been examined in detail and reported in the open literature. Some of the work was funded by the industry and eventually utilized in industrial-scale processing. The objective of this article is to summarize the key developments for a wider global readership. An outline of ongoing drying R&D will be provided in the closing section.     

The effect of fruit extracts with polyphenol oxidase (PPO) activity on the in vitro accessibility of iron in high-tannin sorghum

Dephytinized high-tannin sorghum flour was incubated with crude extracts from pear, banana or avocado, respectively, followed by investigation of the effects on the phenolic content and on in vitro accessible iron. All fruits contained polyphenol oxidase (PPO) activity and incubation resulted in significant reduction of phenolic compounds. Incubation with avocado extract resulted in the lowest levels of phenolic compounds, as well as the highest amount of in vitro accessible iron. Peroxidase activity and some organic acids in the fruit extracts might also have contributed to the positive effect on iron accessibility. Nevertheless, incubation of the sorghum flour with the fruit extracts under conditions enabling the PPO to oxidize phenolic compounds, resulted in the highest accessibility of iron. The results from this study suggest that the PPO activity in simple fruit extracts can be utilized to increase the accessibility of iron in dephytinized polyphenol-containing cereal foods.     

毛泽东关于学习利用资本主义的思想

提出学习、利用资本主义文明成果的具体内容和制定学习、利用资本主义的策略原则,是毛泽东关于学习、利用资本主义思想的主要之点。     

Comparison of Antioxidant Activity of Grape Seed Extract and Fruits Containing High β-Carotene,Vitamin C,and E

Antioxidant activity of a potent antioxidant, grape seed extract, and fruits containing high β-carotene, vitamin C, and vitamin E was measured and compared by 2,2-diphengl-1-picrylhydrazyl radical and ferric reducing antioxidant power assay. The results showed that antioxidant activity of a 20-mg capsule of grape seed extract was approximately 10 to 20 times greater than 1 g of tomato, papaya, banana, and mango. However, if antioxidant activity was calculated per fruit or piece of fruit, the values were comparable. Therefore, consumption of fruit could be a cost-effective way of healthy eating when the price of a dietary supplement is relatively high.     

Ozone-induced changes of antioxidant capacity of fresh-cut tropical fruits

The effect of ozone treatment on total phenol, flavonoid, and vitamin C content of fresh-cut honey pineapple, banana ‘pisang mas’, and guava was investigated. The fresh-cut fruits were exposed to ozone at a flow rate of 8 ± 0.2 ml/s for 0, 10, 20, and 30 min. The antioxidant capacity of the fruits was evaluated by measuring the ferric reducing/antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. Total phenol and flavonoid contents of pineapple and banana increased significantly when exposed to ozone for up to 20 min, with a concomitant increase in FRAP and DPPH values. The opposite was observed for guava. Ozone treatment significantly decreased the vitamin C content of all three fruits. The study shows promising results for enhancing antioxidant capacity of some fresh fruits by ozone treatment although the positive effect is compromised by a reduction in vitamin C content.Industrial relevanceThe preservation of antioxidant properties, storage stability and safety is of utmost importance in the minimally processed fresh food industry. Ozone has been looked into as an alternative sanitizing technology in the fresh produce industry. The results of this study indicate that ozone can be used in the minimally processed fresh food industry to enhance the antioxidant status of fresh-cut fruits.     

Effects of a family-based sensory education on vegetable and fruit variety in children

Several experimental studies implemented in schools have shown that sensory education reduces children’s neophobia and increases their sensory discrimination abilities. However, it is not known whether sensory education has an effect on children’s consumption, particularly on the variety of fruits and vegetables consumed, and whether it is effective when implemented in families.The effect on fruit and vegetable intake of a five months family-based sensory programme was examined in children aged 7–11 (with 32 children in the intervention group and 19 in the control group). The children's parents completed four 24-hour recalls at the beginning and after the intervention to assess their children’s fruit and vegetable intake. Variety indexes were calculated on the basis of the number of different fruits or vegetables consumed during the four 24-hour recalls.The results showed that the vegetable variety decreased in the control group, while it remained stable in the intervention group. No effects of the programme were observed for the fruit variety.The sensory education programme implemented in families prevented the variety of vegetables from decreasing over time. The results of this preliminary study and its long-term effects need to be confirmed by further investigations, with a different methodology than the 24-hour recall.     

Second order derivative spectrophotometric method for determination of vitamin C content in fruits,vegetables and fruit juices

A second-order derivative UV spectrophotometric method for determination of vitamin C [ascorbic acid (AA)] content in a variety of natural samples is described. The method is based on the measurement of a peak–baseline amplitude in the second derivative of the AA spectrum at 267.5 nm. The following corresponding regression equation was obtained within the concentration range 2×10^-5 to 1×10^-4 M AA (3.5–17.6 g/cm³ AA) in 1.0 M HCl solution: ²D_267.5=2.420×10⁴ c+0.025; the correlation coefficient was 0.9993 and the detection limit 4.2×10^-6 M. The results obtained by analysing 21 different species of fruits, vegetables and juices indicated a possibility for a more extensive application of the proposed method. This method is rapid, simple and requires no pretreatment of the analysed material, which makes it suitable for routine analyses. The reliability of the method was confirmed by comparative determinations with the generally accepted 2,6-dichloroindophenol method.