Radiation processing of papad - A sustainable method to improve safety and shelf life

Papad is a popular traditional Indian snack food that is also consumed as an accompaniment to meals. The papad industry in India is predominantly a cottage industry, mainly run by women. Due to microbial contamination and infestation, papad has a shelf life of only a few months. However, increased domestic consumption and export requirements necessitate a longer shelf life. Chemical preservatives are generally added to increase shelf life. Our studies have shown that radiation processing (2 kGy) can be used to extend the shelf life. Unirradiated samples spoiled in three months with visible fungal growth and insect infestation. Irradiated (2 kGy) papad had a shelf life of one year, was sensorily acceptable, showed no microbial counts, and hence has great export potential.

Effect of radiation processing on the quality of chilled meat products

Effect of radiation processing on the shelf-life and safety of some ethnic Indian meat products like chicken chilly, mutton shammi kababs and pork salami during chilled storage was investigated. Radiation processing resulted in dose dependent reduction in microbial counts. A dose of 3 kGy was found to be optimal for the shelf-life extension. In all the three irradiated (3 kGy) meat products the shelf-life was extended by more than 2 weeks at 0-3 °C compared to the corresponding non-irradiated samples. Staphylococcus spp. were completely eliminated by irradiation at a dose of 2 kGy. Some increase in lipid peroxidation on irradiation was observed as measured by TBA assay but it did not affect the sensory attributes of the product.

Potato peel extract-a natural antioxidant for retarding lipid peroxidation in radiation processed lamb meat

The effective utilization of potato peel, a waste generated in large quantities by the food industry, as an antioxidant was investigated. Potato peel extract (PPE) exhibited high phenolic content (70.82 mg of catechin equivalent/100 g), chlorogenic acid (27.56 mg/100 g of sample) being the major component. The yield of total phenolics and chlorogenic acid increased by 26 and 60%, respectively, when the extract was prepared from gamma irradiated (150 Gy) potatoes. PPE showed excellent antioxidant activity as determined by beta-carotene bleaching and radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH). The suitability of PPE for controlling lipid oxidation of radiation processed lamb meat was also investigated. PPE (0.04%) when added to meat before radiation processing was found to retard lipid peroxidation of irradiated meat as measured by TBA number and carbonyl content. The antioxidant activity of PPE was found to be comparable to butylated hydroxytoluene (BHT).

Shelf-stable and safe intermediate-moisture meat products using hurdle technology

A number of ready-to-use shelf-stable intermediate-moisture (IM) spiced mutton and spiced chicken products were developed with a combination of hurdles (reduced moisture, vacuum packing, and irradiation). The water activity of the products was reduced to about 0.80 either by grilling or by hot-air drying. These IM products were vacuum packed and subjected to gamma radiation processing at 0 to 10 kGy. Microbiological analyses revealed a radiation dose-dependent reduction in total viable counts and in numbers of Staphylococcus species. IM meat products that did not undergo radiation treatment showed visible mold growth within 2 months. The products subjected to irradiation at 10 kGy showed an absence of viable microorganisms and also retained high sensory acceptability for up to 9 months at ambient temperatures.