Research Publications (Food Safety)

Fresh-cut fruits have a limited postharvest life compared to fresh intact fruits; they have gained considerable market share. In this study, we investigated the effectiveness of melatonin (1 mM) and ascorbic acid (20 mM) treatments, alone or in combination, on qualitative traits and antioxidant systems of fresh-cut avocado fruits during 14 days of cold storage (4 ± 0.5 °C and RH 95 ± 0.5%).

During the last years, the worldwide market of fruit-based foods, mainly juices and fresh-cut commodities, has experienced an increasing consumption trend, which can be mainly attributed to changes in the human lifestyles. However, mechanical operations used during processing, as well as the chemical compounds and presence of native microorganisms, bring a rapid deterioration of juices and fresh-cut fruits.

Non-uniform heating of RF energy is the main obstacle for its large-scale application in blanching. In this study, we proposed a new blanching method: steam (ST)-assisted radio frequency (RF) blanching of fresh-cut stem lettuce cuboids.

Phenolic compounds are secondary metabolites and widely distributed in higher plants. When plants are subjected to injury stress, the rapid synthesis of more phenols is induced to result in injury defense response for wound healing and repair. Fresh-cut fruits and vegetables undergo substantial mechanical injury caused by pre-preparations such as peeling, coring, cutting and slicing. These processing operations lead to activate the biosynthesis of phenolic compounds as secondary metabolite.

Postharvest deterioration can result in qualitative and quantitative changes in the marketability of horticultural commodities, as well as considerable economic loss to the industry. Low temperature and controlled atmosphere conditions (low O2 and elevated CO2) are extensively employed to prolong the postharvest life of these commodities. Nevertheless, they may suffer from chilling injury and other physiological disorders, as well as excessive water loss and bacterial/fungal decay.

Use of silver nanoparticles (Ag NPs) in pesticides may lead to residual levels in food crops, thus raising food safety and environmental concerns. Since little is known about Ag NP behavior in wash water during typical commercial washing of fresh produce, this study assessed the temporal changes in Ag NP behavior when exposed to 2–100 mg/L free chlorine (Cl 2 ) in simulated lettuce wash water for up to 10 days.

The combined use of ultraviolet-C light-emitting diodes (UV–C LED) irradiation and antimicrobial packaging film was used to secure the safety of fresh-cut vegetables. The antimicrobial packaging film was prepared by adding grapefruit seed extract (GSE) and zinc oxide nanoparticles (ZnO) to a blend film of poly(lactide) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT).

Outbreaks involving romaine and iceberg lettuce are frequently reported in the United States. Novel technologies are needed to inactivate pathogens without compromising product quality and shelf life. In this study, the effects of a process aid composed of silver dihydrogen citrate, glycerin, and lactic acid (SGL) on Escherichia coli and Listeria monocytogenes concentrations on lettuce immediately after washing and during cold storage were evaluated.

Journal of Food Processing and Preservation, Accepted Article. Fresh-cut fruits and vegetables refer to edible commodities that are free from large scale and typical traditional processing operations. However, maintaining their nutritional value and microbiological integrity is challenging. The processing operations such as peeling, cutting and trimming done in the fresh-cut industry can trigger deteriorative reactions such as tissue softening and enzymatic browning.

Journal of Food Processing and Preservation, Accepted Article. Fresh-cut fruits and vegetables are prone to browning that leads to quality decline, low acceptability and food waste. Therefore, it is of great importance to study and alleviate the browning of fresh-cut fruits and vegetables. Plant extracts, rich in bioactive compounds like polyphenols, flavonoids, terpenes and other active ingredients, exhibit high antioxidant and anti-browning ability.

Journal of Food Processing and Preservation, Accepted Article. In this study, high intensity ultrasound (HIU), antibrowning chemicals (calcium chloride and ascorbic acid), water bath were used to avoid the browning of kiwifruit pieces, and the shelf-life of fresh-cut was measured (two weeks). The treated fresh-cut kiwi samples were evaluated in terms of color, enzyme activities, bioactive compounds, microbial and sensory studies.

Zoning is typically adopted by food manufacturers and classified into three different zones including Zone 1 (food contact surface), Zone 2 (proximity to food and food contact surfaces) and Zone 3 (remote surfaces from processing). In this study, environmental surfaces belonging to these three Zones were sampled during food processing in a FVs processing facility located in Beijing, China.

Twenty types of fruits and vegetables representing a broad range of fresh produce categories were assessed for the growth potential and growth kinetics of Listeria monocytogenes under conditions reflecting commercial practices for storage and distribution and conditions reflecting sustained temperature abuse. Whole and fresh-cut produce was obtained from various commercial sources and inoculated with L.

The loss of fresh produce along the supply chain represents a significant contributor to environmental and economic burden. Although technological advances in distribution and storage have provided a means to reduce the loss of fresh produce, in resource-limited settings, these technologies may not be available. One attractive approach to help address this limitation is to use edible coatings to protect fresh produce from biotic and abiotic factors that cause food deterioration.

In fresh-cut vegetables, plant tissues are often challenged by (a)biotic stresses that act in combination, and the response to combinatorial stresses differs from that triggered by each individually. Phenolic induction by wounding is a known response contributing to increase products phenolic content. Heat application is a promising treatment in minimal processing, and its interference on the wound-induced response is produce-dependent.

This study evaluated the microbiological contamination of fresh-cut produce in Korea. A total of 108 fresh-cut vegetables and fruits were surveyed for the aerobic mesophilic (AM) count, aerobic psychrophilic (AP) count, total coliform, generic Escherichia coli, yeast and mold, and foodborne pathogens. AM counts ranged from 1.00 to 7.36 log CFU/g, and AP counts showed very similar results as AM counts. For total coliform and generic E.

Author(s): Tianqi Zhang, Wan-Ning Lee, Yaguang Luo, Ching-Hua Huang

Author(s): Jun Xian Wong, Suzita Ramli, Shakinaz Desa, Sook Ngoh Chen

This study was conducted to compare the efficacy of two sanitizing agents (chlorine and PAA) in reducing (both spoilage and pathogenic) microorganisms and in reducing disinfection by-products ( DBPs) in the washing stage of three types of minimally processed vegetables: Iceberg lettuce, carrots and baby leaves. These fresh-cut products are consumed uncooked and, hence, a proper sanitation is essential in preventing food-borne illness outbreaks.

Author(s): Yingshu He, Ruixi Chen, Yan Qi, Joelle K. Salazar, Shimei Zhang, Mary Lou Tortorello, Xiangyu Deng, Wei Zhang

Modified atmosphere packaging (MAP) is widely used for the preservation of fresh-cut fruit and vegetables. But many commercial polymeric films are limited to MAP applicability due to a low gas permeability of these films. Laser perforation is a novel method to provide micropores that raises gas permeability.

Author(s): Yan Man, Meijing Ban, An Li, Xinxin Jin, Yuanfang Du, Ligang Pan

In the present study, we evaluated the antimicrobial activity of passion fruit peel extract (PPE) against Escherichia coli O157:H7 and Listeria monocytogenes. The application of PPE using an electrostatic spraying system for the disinfection of fresh-cut Lollo Rossa and beetroot leaves was also examined and compared with conventional PPE washing.

Inoculation studies are important when assessing microbial survival and growth in food products. These studies typically involve the pregrowth of multiple strains of a target pathogen under a single condition; this emphasizes strain diversity.

Author(s): Liping Qiao, Man Gao, Jiaxuan Zheng, Jingyan Zhang, Laifeng Lu, Xia Liu