K. Santhanam

Improvement of juice recovery from pineapple pulp/residue using cellulases and pectinases

Abstract During stepwise extraction of pineapple juice from pineapple pulp/residue, the addition of a commercial cellulase, a pectinase or their mixture at an enzyme concentration of 0.025% at 27–30°C for 30 min, facilitated juice recovery. The percent juice recovery in some batches of pineapple after enzyme addition was in the range of 81–86% as against 72% in the untreated samples. Enzyme additions also improved the quality of juice by allowing extraction of more of the soluble solids and juice particulate. The ready-to-serve (RTS) pineapple juice obtained after enzymatic juice extraction was rated acceptable on a 5-point Hedonic scale.

Effect of coriander seeds on hexachlorocyclohexane induced lipid peroxidation in rat liver

The effect of prefeeding of coriander seed powder (CSP) at 10% level on hexachlorocyclohexane (HCH) induced oxidative stress in rat liver was studied. The prefeeding of rats with CSP was found to reduce the HCH-induced rise in conjugated dienes, hydroperoxide and malondialdehyde (MDA) contents in liver. The intra peritonial injection of HCH reduced hepatic superoxide dismutase (SOD), catalase, glutathione S-transferase (GS-t), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione reductase (GSSGR) activities in liver, where as the hepatic glutathione peroxidase (GSH-Px) and kidney γ-glutamyltranspeptidase (GGT) activities were elevated. The prefeeding of CSP per se increased hepatic SOD, catalase, GS-t, G-6-PDH and GSSGR activities as well as in CSP prefed and then HCH-administered rats. The work shows the modulation of hepatic antioxidant system as a result of the prefeeding of CSP, which were otherwise reduced by HCH injection. The results reported here elicit the antioxidative effect of coriander seeds against HCH-induced formation of free radicals in rat liver.

The use of commercial enzymes in white grape juice clarification

Abstract A commercial pectinase from Aspergillus niger containing various polysaccharases clarified the white grape juice to an extent of 98–99% and also degraded the grape mash by 25–30%. This was achieved by optimising the grape mash treatment with 0.048% of enzyme at 27–30°C for 30 min without changing the mash pH. After pectinolytic juice clarification, both juice viscosity and total phenols were reduced by 25% and 32% respectively.

Anticarcinogenic effects of curry leaves in dimethylhydrazine-treated rats

Curry leaves are one of the spices used in Indian dishes for aroma and preservation. There are no reports on the antioxidant properties of curry leaves. In this study, the antioxidant potential of curry leaves in rats treated with a known chemical carcinogen, dimethylhydrazine hydrochloride (DMH) was investigated. Food intake was reduced in the rats fed curry leaf-supplemented diet but the body and the organ weights were not affected.Vitamin A content in the liver was significantly increased whereas glutathione (GSH) content was not altered. A 50% reduction was seen in the micronuclei induced by DMH and a 30% reduction in the activity of γ,-glutamyl transpeptidase when the rats were fed a curry leaf-supplemented diet. These results indicate that curry leaves have highpotential as reducer of the toxicity of DMH.

Proximate and mineral composition of some processed traditional and popular Indian dishes

Abstract Proximate and mineral composition of 30 different traditional and popular Indian foods, categorised as either ready-to-eat or easy-to-reconstitute or freeze dried products have been evaluated. Of the 30 products, the proximal score of eleven and mineral composition of two items have been reported recently, elsewhere. The various products employed for the present study include vegetable pulav, dehydrated pulses/curries, upma, mutton/chicken curry, which form part of main meals, and certain fruit beverage powders of pineapple, mangoes and grapes. All the products, tested for their shelf stability (minimum of 6–12 months at ambient conditions) and microbiological safety, have been found to provide approximately 350–660 kcals 100 g −1 (on moisture-free-basis), depending on the type of product. The pulse, meat/chicken items were found to be protein-rich. Fat content in all the products varied, depending on the amount of hydrogenated oil used in their preparations. However, the fruit-based products contained negligible amounts of both protein and fat. The various minerals and trace elements analysed, include sodium, potassium, calcium, magnesium, phosphorus, iron, zinc, copper, manganese, aluminium and lead. The elemental composition of each of the products varied with the different ingredients going into their preparation. However, it is noteworthy, that contaminants such as lead and aluminium are present in quantities well below the limits prescribed by standard institutions such as PFA and ASC. The nutrient database generated hitherto, while suggesting that the products are nutritionally good/safe, also enables nutrient-labelling of the products. Further, it helps the nutritionists and food planners to formulate different diets to meet the varied needs of the consumer.

Proximate composition and dietary fibre content of various foods/rations processed to suit the Indian palate

The proximate composition and dietary fibre contents of various processed foods either in ready-to-eat (RTE) or easy-to-reconstitute (ETR) form have been evaluated. The RTE foods included flavoured chapathy (unleavened bread), spiced potato chapathy and chikki (peanut candy), while the ETR foods contained items such as precooked dehydrated (PD) khichdi, PD vegetable pulav (rice based item), PD green gram dal curry, instant upma mix and instant halwa mix. Three different rations formulated out of these products have also been studied. Among the individual items studied, instant halwa and upma mixes have been found to be calorie dense (5400 kcal kg−1 FW). The other items provided about 3000 to 4700 kcal kg−1 FW. The rations, on the other hand, provided about 3500 kcal person−1 day−1. All the food items except instant halwa mix were found to contain high amounts of insoluble and total dietary fibre (TDF). The rations were estimated to provide 60–70 g TDF person−1 day−1.

EFFECT OF DEHYDRATED CARROT ON THE ANTIOXIDANT ENZYMES AND MICRONUCLEI FORMATION IN RATS CHALLENGED WITH DIMETHYLHYDRAZINE

Abstract The modulation of detoxifying enzymes; catalase, glutathione peroxidase (GSH-Px), glutathione reductase (GSSGR), glutathione-S-transferase (GST) in liver and γ-glutamyl transpeptidase (GGT) in kidney elicited by pre feeding of dehydrated carrot at 10 and 20% levels with or without the treatment with dimethylhydrazine (DMH) was studied in rats. The pre-feeding of rats with carrot was found to elevate the hepatic GSH content with concomitant increase in activities of GSH-Px, GSSGR and GST of rats injected with DMH. The DMH — induced increase in TBARS, GGT and micronuclei (MN) was significantly reduced by the ingestion of carrot. It is suggested that short term consumption of carrot has variable effects on the modulation of different detoxifying enzymes and on the DMH — induced micronuclei formation.

Quality of Textured Soya Protein During Storage in Different Packaging Materials

Abstract The shelf stability of textured soya protein (TSP) procured from a single source and packaged in seven different packaging materials [viz. low density polyethylene (LDPE), HDPE, and polypropylene (PP) of 300 and 500 G and HDPE–LDPE–HDPE] in quantities of 10 kg each and stored at three different climatic conditions (viz hot and dry—Jodhpur; hot and humid—Tezpur; normal Mysore) for one year was studied. At the end of 6, 9, and 12 months, samples were drawn and analyzed for the quality parameters like moisture, browning, thiobarbituric acid reactive substances (TBARS), uric acid, water holding capacity (WHC), available lysine, in vitro digestibility, and sensory attributes. Anti nutritional factors like trypsin inhibitor activity (TIA) and phytic acid were also evaluated. The changes in the moisture content and non‐enzymatic browning correlated well with the relative humidity of the place of storage. However the TBARS showed wide variations while the WHC varied between 2.6 and 2.9 of water/g material. Interestingly the TIA showed a ten‐fold decrease (6.65 vs. 0.68 mg/g). The reduction in available lysine (6.33 vs. 5.29/16 g N) correlated well with the observed reduction in in vitro digestibility (84% vs. 73%). Although the sensory quality showed a decline by the end of 12 months storage period, the overall acceptability of the product on the 9 point Hedonic scale, remained very good. It is inferred from the present study that packaging of TSP in HDPE‐500 Primary Sac and HDPE woven Secondary Sac, keeps the product shelf stable up to one year even under diverse climatic conditions.