Modified Atmospheric Packaging of Fresh-Cut Amaranth (Amaranthus tricolor L.) for Extending Shelf Life

Fresh-cut vegetables are prone to microbiological contamination and oxygenation during handling and storage. In this study, fresh-cut amaranth was subjected to various gas ratios (5–15% O2, 5–15% CO2, 80% N2) for 12 days. Chlorophyll content, ascorbic acid content, antioxidant enzyme activity, microbial population, and physiological and biochemical indicators were measured to evaluate the impact of atmospheric packaging. Suitable atmospheric packaging could slow the respiration of amaranth, delay the decline in physiological and biochemical characteristics, maintain the antioxidant enzyme activity, promote the sensorics, and prolong the shelf life by 2 days. According to the analysis of the results, modified atmospheric packaging (10% O2, 10% CO2, 80% N2) retarded the decline in fresh-cut amaranth quality, provided effective antioxidative browning, and inhibited Pseudomonas fluorescens development.

Detection of Volatiles from Raw Beef Meat from Different Packaging Systems Using Solid-Phase Microextraction GC–Accurate Mass Spectrometry

The volatile profile of raw beef contains vital information related to meat quality and freshness. This qualitative study examines the effect of packaging system on the formation and release of volatile organic compounds (VOCs) from raw beef over time, relative to the packaging best before date (BBD). The three packaging systems investigated were modified atmospheric packaging, vacuum packaging, and cling-wrapped packaging. Porterhouse steak samples with the same BBD were analysed from 3 days before to 3 days after the BBD. VOCs were detected via preconcentration using solid-phase microextraction combined with gas chromatography–accurate mass quadrupole time-of-flight mass spectrometry. In total, 35 different VOCs were tentatively identified. Interestingly, there was no clear relationship of the VOCs detected between the three packaging systems, with only carbon disulphide and acetoin, both known volatiles of beef, detected in all three. This is the first study to investigate the effects of commercial packaging systems on VOC formation; it provides an understanding of the relationship of VOCs to the BBD that is essential for the development of on-pack freshness and quality sensors.

Carbon monoxide modified atmospheric packaging improves ground chicken color and decreases lipid oxidation

Consumersassociate a bright light pink lean color of ground chicken with freshness andwholesomeness. Chicken meat has greater unsaturated fatty acid composition andlower myoglobin content than beef and pork. As a result, chicken is more prone tooxidative quality changes. Carbon monoxide-modified atmospheric packaging (CO-MAP)creates an anaerobic condition that can limit lipid oxidation and improve color.However, limited knowledge is currently available on ground chicken quality. Therefore,the objective of the current study was to evaluate the color changes and lipidoxidation in ground chicken patties packed under aerobic (PVC), high-oxygen modifiedatmospheric packaging (HiOx; 80% O2+20% CO2), and CO-MAP(CO; 0.4% CO+19.6% CO2+80% N2) and stored at 2 °C. Surfacecolor, lipid oxidation, fatty acid profile, and aerobic plate count were determinedduring storage. Patties packaged in PVC had greater (P< 0.05) pH than HiOx- and CO-MAP. Gas chromatography analysis indicated groundchicken has 72.8% unsaturated fatty acids and 27.2% saturated fatty acids. Theformation of carboxymyoglobin on ground chicken patty surface was confirmed bySoret peak at 420 nm and 570 nm, while oxymyoglobin had peaks at 410 nm and 580nm. Both HiOx- and CO-MAP had greater redness and lower surface discolorationthan PVC on day 4 of storage. Lipid oxidation was greater (P < 0.05) inPVC and HiOx-MAP than CO-MAP. Carbon monoxide inclusion at 0.4% level effectivelyinhibited lipid oxidation and stabilized surface redness during refrigeratedstorage of ground chicken.  

High carbon-di-oxide modified atmospheric packaging on quality of ready-to-eat minimally processed fresh-cut iceberg lettuce

Fresh-cut lettuce is a very well-known salad for today's routines because it obliges minimal preparation to minimize the loss of health beneficial vitamins, minerals, antioxidants and other phytochemicals. It is a prodigious challenge to serve its consumers fresh. Quality of freshly processed lettuce under high CO2 modified atmosphere packaging (MAP) has been investigated as a realistic alternative technique for its preservation. Storage under high CO2 atmospheric treatments exhibited a significant impact in microbial development, electrolyte leakage, volatile metabolites and sensory quality of fresh-cut iceberg lettuce. This storage condition (MAP 1: 5 kPa O2 and 20 kPa CO2 balanced by N2 at 7 °C for 6 days) inhibited the growth of mesophilic bacteria and yeasts; delayed the enzymatic browning (cut-edges and intact surface) of fresh-cut iceberg lettuce and overall visual quality was also in acceptance limit. The development of off-odors was perceived in high CO2 MAP as a consequence of volatiles (ethanol and acetaldehyde) accumulation which was persisted at an inexcusable level during 6 days of storage periods.