scholarly journals Pasta packaging with bio-based barrier to prevent insect infestation

Author(s):  
Urška Vrabič Brodnjak ◽  
◽  
Pasquale Trematerra ◽  

The results of the infestation by maize weevil, Sitophilus zeamais (Coleoptera, Curculionidae) in various packages filled with pasta are presented. Three different types of packaging were used, i.e. two paper tubes (a novel one laminated with bio-based polyethylene and one without lamination) and a commercially available polypropylene pillow pouch packaging. Material properties such as moisture and water resistance and compressive strength were analysed. The results obtained showed that adult maize weevils revealed significant preferences to penetrate the pasta packaging through the already existing holes that were present in the polypropylene packaging, whereas no infestation was observed inside the paper tube packaging. The study showed that the shape and construction, e.g. tube packaging with an innovative bio-polyethylene film, is very effective against insect infestation and mechanical overload.

Author(s):  
Н. Кожухова ◽  
Natal'ya Kozhuhova ◽  
Д. Данакин ◽  
Dmitriy Danakin ◽  
В. Строкова ◽  
...  

Synthesis of binders and materials characterized by polycomponent composition, generally, is associated with necessity of improvement of certain properties or formation of principally new characteristics in this materials. In this paper hybrid geopolymers based on fly ash were synthesized using different types of mineral modifiers such as Portland cement (PC), kaolin, metakaolin (MK). It was defined, that values of compressive strength, water resistance and water absorption for PC-containing geopolymers are better than free of modifier geopolymer as well as for kaolin- and MK-containing geopolymers. It was determined that high-temperature treatment (at 600 °C) provides with reinforcing and improvement of water resistance of kaolin- and MK-containing hybrid geopolymers. PC-containing hybrid geopolymers demonstrated a sharp reducing in compressive strength and average density. For this system, in temperature range of 400–600 °C a dramatic growth of compressive strength is observed when average density grows or a constant. Thus, PC-containing hybrid geopolymers are not thermal resistant, that confirmed by degradation of its performance characteristics under high temperature effect.


2018 ◽  
Vol 5 (9) ◽  
pp. 261-269
Author(s):  
Oladele A. Olaniran ◽  
Samuel A. Babarinde ◽  
Fatai O. Alao ◽  
Adetayo D. Adeleye ◽  
Afeez Ige ◽  
...  

Okra Abelmoschus esculentus (L.) Moench (Malvales: Malvaceae) is a major fruit vegetable consumed in either fresh or dried form in Africa. As part of our efforts to identify the pestiferous species attacking dried fruits, a laboratory experiment was conducted to investigate the damage potentials of Sitophilus zeamais (Motschulsky, 1855) (Coleoptera: Curculionidae) and Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae) against dried okra. Three levels of infestations (5, 10 and 20 adults of each insect) on dried okra and okra without insect infestation, which served as control were kept under ambient conditions. The experiment was laid out in completely randomized design and replicated thrice. Data were collected on percentage insect mortality, okra weight loss and proximate composition. Percentage mortality increased with storage duration, while weight loss was significantly affected by insect infestation levels and ranged from 0.04%-0.18%, 0.07%-0.21%, 0.08% 0.22%, 0.07%-022%, 0.11% 0.22% and 0.12%-0.23% for 1, 2, 3, 4, 5 and 6 weeks after infestation, respectively. Crude fibre significantly increased with insect infestation (13.98%-14.62% for the infested okra compared with 9.12%-13.63% in the control), while other proximate components were not significantly affected. The results show that the two species pose no serious threat to intact dried okra, in the short term, but long term multiple generation infestation of dried okra by the insects may cause greater damage.


2015 ◽  
Vol 5 (4) ◽  
pp. 236-243
Author(s):  
Sylvia A. Opiyo ◽  
Lawrence O. A. Manguro ◽  
Dorothy A. Okoth ◽  
Anjeline A. Ochung ◽  
Charles O. Ochieng

2021 ◽  
Vol 13 (4) ◽  
pp. 2407
Author(s):  
Guang-Zhu Zhang ◽  
Xiao-Yong Wang ◽  
Tae-Wan Kim ◽  
Jong-Yeon Lim ◽  
Yi Han

This study shows the effect of different types of internal curing liquid on the properties of alkali-activated slag (AAS) mortar. NaOH solution and deionized water were used as the liquid internal curing agents and zeolite sand was the internal curing agent that replaced the standard sand at 15% and 30%, respectively. Experiments on the mechanical properties, hydration kinetics, autogenous shrinkage (AS), internal temperature, internal relative humidity, surface electrical resistivity, ultrasonic pulse velocity (UPV), and setting time were performed. The conclusions are as follows: (1) the setting times of AAS mortars with internal curing by water were longer than those of internal curing by NaOH solution. (2) NaOH solution more effectively reduces the AS of AAS mortars than water when used as an internal curing liquid. (3) The cumulative heat of the AAS mortar when using water for internal curing is substantially reduced compared to the control group. (4) For the AAS mortars with NaOH solution as an internal curing liquid, compared with the control specimen, the compressive strength results are increased. However, a decrease in compressive strength values occurs when water is used as an internal curing liquid in the AAS mortar. (5) The UPV decreases as the content of zeolite sand that replaces the standard sand increases. (6) When internal curing is carried out with water as the internal curing liquid, the surface resistivity values of the AAS mortar are higher than when the alkali solution is used as the internal curing liquid. To sum up, both NaOH and deionized water are effective as internal curing liquids, but the NaOH solution shows a better performance in terms of reducing shrinkage and improving mechanical properties than deionized water.


Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 532
Author(s):  
William R. Patiño-Bayona ◽  
Leidy J. Nagles Galeano ◽  
Jenifer J. Bustos Cortes ◽  
Wilman A. Delgado Ávila ◽  
Eddy Herrera Daza ◽  
...  

Chemical control of the maize weevil (Sitophilus zeamais) has been ineffective and presents serious collateral damage. Among plant-derived insecticides, essential oils (EOs) are suitable candidates to control this stored products pest. In this work, the insecticidal activities of 45 natural EOs against S. zeamais adults were screened, and the most promising ones (24 EOs) were characterized by GC–MS. The repellent and toxic effects (contact and fumigant) of these 24 EOs were determined, and by a cluster analysis they were classified into two groups considering its fumigant activity and contact toxicity. For the EOs with the highest fumigant potential (14 oils) and their main active constituents (17 compounds), lethal concentrations were determined. The most active EOs were those obtained from L. stoechas and L. alba, with LC50 values of 303.4 and 254.1 µL/L air and characterized by a high content of monoterpenes. Regarding the major compounds, the oxygenated monoterpenes R-(+)-pulegone (LC50 = 0.580 mg/L air), S-(-)-pulegone (LC50 = 0.971 mg/L air) and R-(-)-carvone (LC50 = 1.423 mg/L air) were the most active, as few variations in their concentrations significantly increased insect mortality.


2021 ◽  
Vol 13 (9) ◽  
pp. 1846
Author(s):  
Vivek Kumar ◽  
Isabel M. Morris ◽  
Santiago A. Lopez ◽  
Branko Glisic

Estimating variations in material properties over space and time is essential for the purposes of structural health monitoring (SHM), mandated inspection, and insurance of civil infrastructure. Properties such as compressive strength evolve over time and are reflective of the overall condition of the aging infrastructure. Concrete structures pose an additional challenge due to the inherent spatial variability of material properties over large length scales. In recent years, nondestructive approaches such as rebound hammer and ultrasonic velocity have been used to determine the in situ material properties of concrete with a focus on the compressive strength. However, these methods require personnel expertise, careful data collection, and high investment. This paper presents a novel approach using ground penetrating radar (GPR) to estimate the variability of in situ material properties over time and space for assessment of concrete bridges. The results show that attributes (or features) of the GPR data such as raw average amplitudes can be used to identify differences in compressive strength across the deck of a concrete bridge. Attributes such as instantaneous amplitudes and intensity of reflected waves are useful in predicting the material properties such as compressive strength, porosity, and density. For compressive strength, one alternative approach of the Maturity Index (MI) was used to estimate the present values and compare with GPR estimated values. The results show that GPR attributes could be successfully used for identifying spatial and temporal variation of concrete properties. Finally, discussions are presented regarding their suitability and limitations for field applications.


2021 ◽  
Vol 82 (1) ◽  
Author(s):  
Sobifagha Princess Bell-Gam ◽  
Luke Chinaru Nwosu ◽  
Kayode David Ileke ◽  
Uwaoma Otuodichinma Aguwa

Abstract Background The use of X-ray irradiation in the control of the maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) infesting stored maize was tested at 60, 70 and 80 KeV as part of the international concerted efforts to save maize production and enhance food security. Investigations were done in the laboratory at mean temperature and relative humidity of 29.2 °C and 75.7%, respectively using three varieties of maize. The possibility that X-ray irradiation can affect the viability of maize grains when planted after weevil control process was also evaluated in the laboratory. Standard methods were used to achieve the specific objectives, and X-ray machine snap constituted the exposure time for each dose. Results The results revealed 10% mortality of adult weevils after 24 h and 40% mortality after a period of 7 days. The result indicates moderate effect on mortality. Progressive increase in mortality was recorded as dose increased from 60 to 80 KeV. X-ray irradiation at the doses tested did not significantly (P > 0.05) restrict S. zeamais emergence from maize grains and did not also significantly protect grains against damage and flour production. There was no difference in the pattern of daily emergence of new progenies and pattern of accumulated emergence. The relationship between X-ray irradiation doses and weight of emerging progenies require more specific analysis. Absence of significant difference between the viability of irradiated grains and un-irradiated grains strongly suggests that X-ray irradiation did not adversely affect seed viability, and this gives irradiation technique an opportunity of higher acceptability in agriculture. Conclusions We recommend > 80 KeV of X-ray irradiation or its incorporation into integrated pest management system in order to achieve effective post-harvest control of the pest.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 879
Author(s):  
Clíssia Barboza da Silva ◽  
Alysson Alexander Naves Silva ◽  
Geovanny Barroso ◽  
Pedro Takao Yamamoto ◽  
Valter Arthur ◽  
...  

The application of artificial intelligence (AI) such as deep learning in the quality control of grains has the potential to assist analysts in decision making and improving procedures. Advanced technologies based on X-ray imaging provide markedly easier ways to control insect infestation of stored products, regardless of whether the quality features are visible on the surface of the grains. Here, we applied contrast enhancement algorithms based on peripheral equalization and calcification emphasis on X-ray images to improve the detection of Sitophilus zeamais in maize grains. In addition, we proposed an approach based on convolutional neural networks (CNNs) to identity non-infested and infested classes using three different architectures; (i) Inception-ResNet-v2, (ii) Xception and (iii) MobileNetV2. In general, the prediction models developed based on the MobileNetV2 and Xception architectures achieved higher accuracy (≥0.88) in identifying non-infested grains and grains infested by maize weevil, with a correct classification from 0.78 to 1.00 for validation and test sets. Hence, the proposed approach using enhanced radiographs has the potential to provide precise control of Sitophilus zeamais for safe human consumption of maize grains. The proposed method can automatically recognize food contaminated with hidden storage pests without manual features, which makes it more reliable for grain inspection.


Sign in / Sign up

Export Citation Format

Share Document