Influence of two sterilisation ways, gamma-irradiation and heat treatment, on the volatiles of black pepper (Piper nigrum L.)

Abstract

Sádecká J. (2010): Influence of two sterilisation ways, gamma-irradiation and heat treatment, on the volatiles of black pepper (Piper nigrum L.). Czech J. Food Sci., 28: 44-52.The objective of this study was to investigate and compare the effects of ionising irradiation with different doses of gamma-rays (5 kGy, 10 kGy, and 30 kGy) versus the effect of heat sterilisation (dry steam, 130°C, 3 min) on the microbiological quality of powdered black pepper. Subsequently, the aim was to determine the impact of these sterilisation ways on the possible changes in the chemical composition and sensory quality (flavour) of black pepper essential oils. Methods of gas chromatography (GC/FID, GC/MS) were utilised for the evaluation of the essential oils compositions. The volatile constituents of black pepper extracts were studied with regard to their particular contribution to the overall aroma by the technique of gas chromatography-olfactometry (GC/O) using the method of Aroma Extract Dilution Analysis [AEDA]. Qualitative compositions of volatile oils obtained from the control sample (0 kGy), samples irradiated at various doses, and heat treated sample were identical. The most significant changes were observed in the contents of volatile compounds after ionising radiation treatment with 30 kGy and heat treatment, respectively. These changes caused a remarkable decrease in the overall aroma of heat sterilised black pepper. Additionally, microbiological analysis showed that the heat treatment was insufficient for an effective reduction/elimination of the polluting microflora present in the analysed sample of black pepper.

Effects of Gamma Radiation on Essential Oils: A Review

“…On the other hand, higher content of trans-sabinene hydrate, 3,4-dimethylstyrene, cyclohexenol, p-cymen-8-ol, terpinen-4-ol, α-terpineol, α-terpineol, eucarvone, piperitenone, piperitone, undecanone, and spathulenol was verified for irradiated samples at 30.0 kGy. The most significant change was observed for irradiated sample at 30.0 kGy, which exhibit an increase of caryophyllene oxide and a proportional decrease of β-caryophyllene in relation to nonirradiated sample [32].…”

Study on the Use of Ionizing Radiation for the Preservation of Spices

“…• The flowering vine, black pepper (Piper nigrum), is in the family Piperaceaeand is cultivated for its fruit [12][14].…”

“…Most significant changes in the chemical composition and in the microbiological quality of black pepper were observed after an ionizing radiation treatment of up to 30 kGy. The highest dose of irradiation used (30 kGy) affected many compounds by increasingthe ratio of many oxygenated compounds (trans-sabinene hydrate, 3,4 dimethylstyrene, cyclohexenol, p-cy-men-8-ol, terpinen-4-ol, α-terpineal,eucarvon, piperitenon, α-terpineol,piperiton,spathulenol, and undecanone) compared with the control [12] [13] .Theresearchgoal is to study the effects of gamma rays at doses of 5, 10, and 20 kGyduring the storage periods on the chemical analysis and microbial quality of black pepper and clove.…”

Fatty acid profile of olive oil extracted from irradiated and non-irradiated olive fruits

“…[9] Food irradiation has been identified as a new technology that can eliminate insects and microorganisms from raw food products extend shelf life and improve the quality and safety of food. [10,11] Irradiation with ionizing energy is widely used to improve the physical, chemical, and biological properties of materials and commercial products. [12,13] The effect of irradiation on locally stored foods is of utmost importance and an insight into these aspects of storage will help in understanding the shelf life of foods as well as its effects on sensitive nutrients.…”