“Effect of various drying methods on quality and flavor characteristics of mint leaves (Mentha spicata L.)”

Mint leaves were dehydrated by hot air, shade as well as microwave drying and the respective drying time found, to lower the moisture content from (88%) to around (5%). The qualities of the dried products were assessed by determining the moisture, chlorophyll, carotenoid, polyphenols, color and volatile oil. In microwave drying, despite the less drying time, there were appreciable losses of volatile oil, chlorophyll and other components when compared to the fresh mint leaves. Results showed that Hot Air Drying (HAD) at 45°C followed by Micro Wave Drying (MWD) at 900 Watts possessed better quality parameters in the dried products suggesting that Hot Air Drying (HAD) was most suitable although it took more time compared to Micro Wave Drying (MWD).

Preparation and storage stability of amla (Phyllanthus emblica) based instant pulihora mix - a South Indian traditional food condiment

Amla (Phyllanthus emblica Linn) is an important crop, indigenous to Indian subcontinent, which is used in alternative medicine, health foods and herbal products. An attempt was made to add value to the highly perishable and seasonable raw material and produce a convenient, shelf stable instant mix for south Indian cuisines. The standardized instant amla pulihora mix (APM) consisted of amla powder (AP, 26%), roasted ground nuts, bengal gram, black gram, green chili, salt (18%) and spices. The titrable acidity of amla powder and amla pulihora mix was 15.1 and 6.4%, respectively. Amla pulihora mix was a rich source of Ca (191.18 mg/100 g), Fe (21.19 mg/100 g) and a considerable amount of proteins (11.2%). The total polyphenol content in amla powder and the amla pulihora mix was found to be 9989 and 3093 mg/100 g, respectively. HPLC analysis revealed that tannic acid and ascorbic acid contents of amla powder were 8102.1, 1601.21 mg/100 g, respectively, and ascorbic acid in amla pulihora mix was found to be 440.21 mg/100 g. Retention of ascorbic acid was higher in the amla pulihora mix (84%), when compared to amla powder (22%), over a storage period of six months. The antioxidant activity (IC50) of amla powder and the amla pulihora mix, as assayed by DPPH and ABTS, were 0.7 and 0.2 mg/ml and 0.28 and 0.17 mg/ml, respectively. Sensory evaluation of the amla pulihora mix indicated that the product was highly acceptable, when mixed with cooked rice in the ratio of 1: 6.9 w/w. The shelf-life of the product was 6 months with a sensory acceptability score of 8. The equilibrium moisture content- relative humidity studies indicated that both the amla powder and amla pulihora mix were non-hygroscopic and stable at room temperature (28±2 °C) up to 6 months when packed in metalized polyester polyethylene pouches. Microbiological analysis indicated both products as safe for consumption up to 6 months storage

Bioactive constituents, sorption behaviour, antioxidant and antimicrobial activity of solar dried ajwain (Trachyspermum copticum L.) leaves

278-284The stability of active compounds, sorption studies, and antioxidant and antimicrobial activity of solar-dried ajwain (Trachyspermum copticum L.) leaves were studied. Fresh ajwain leaf (FAL) on solar drying yielded solar-dried ajwain leaf (SDAL) and was packed in polyethylene pouches for further studies. SDAL was rich in protein, fibre and mineral matter. Active compounds such as β-carotene (17 and 89 mg/100 g) and total chlorophyll (112 and 82 mg/100 g) contents were found in FAL and SDAL respectively. Similarly, higher ascorbic acid and polyphenols content were found in SDAL. Moisture sorption isotherm studies indicated that the SDAL was found to be non-hygroscopic in nature and stable at room temperature. Antioxidant activity as assayed by methanolic extract indicated SDAL had better activity than FAL. The ethanol extract of FAL and SDAL was evaluated for antimicrobial activity by disc diffusion method, which showed that the extract was sensitive at 20 μg/mL concentration on Gram-negative and positive bacteria. The study encourages the isolation and characterization of active ingredients from FAL and SDAL and their application in foods as nutraceuticals

Enzyme-assisted process for production of superior quality vanilla extracts from green vanilla pods using tea leaf enzymes

Vanilla planifolia Andrews is a perennial tropical vine and is an orchid grown for its pleasant flavor. There is an increasing trend world over for using natural flavors. Vanilla being an important food flavoring ingredient, the demand for natural vanilla extract is increasing. Hence, the aim of the present study was to prepare vanilla extract from green beans without going through the elaborate and time-consuming conventional curing process. Vanilla beans after size reduction were mixed in a suitable proportion with tea leaf enzyme extract (TLEE) and incubated to facilitate action of enzymes on vanilla flavor precursors. The beans mix was squeezed, and the filtrate was treated with ethanol to extract the vanilla flavor. TLEE-treated extracts had higher vanillin content (4.2%) compared to Viscozyme extract (2.4%). Also, it had higher intensity of vanilla flavor, sweet, and floral notes. Further, electronic nose analysis confirmed the discrimination between extracts. It was concluded that the use of TLEE is very much useful to obtain higher yield of vanilla extract and superior quality vanilla flavor, which avoids the traditional laborious and time-consuming curing process