Anjan Borah

Anti-oxidant effect of extracts of kinnow rind, pomegranate rind and seed powders in cooked goat meat patties.

To overcome the disadvantages of using synthetic anti-oxidants in meat products, an investigation was carried out to evaluate the anti-oxidant effect of extracts of fruit by-products viz., kinnow rind powder (KRP), pomegranate rind powder (PRP) and pomegranate seed powder (PSP) in goat meat patties. Total phenolics content, DPPH radical scavenging activity and effect of these extracts on instrumental color, sensory attributes and TBARS values during storage (4+/-1 degrees C) of goat meat patties were evaluated. Results showed that these extracts are rich sources of phenolic compounds having free radical scavenging activity. Hunter Lab L value significantly (P<0.05) lowered in PRP followed by PSP and KRP patties. Sensory evaluation indicated no significant differences among patties. Further, a significant (P<0.5) reduction in TBARS values (lipid oxidation) during storage of goat meat patties was observed in PRP, PSP and KRP as compared to control patties. Average TBARS values (mg/kg meat) during refrigerated storage (4+/-1 degrees C) were significantly lower in PRP, followed by PSP and KRP as compared to control. The overall anti-oxidant effect was in the order of PRP>PSP>KRP. It was concluded that extracts of above fruits by-product powders have potential to be used as natural anti-oxidants in meat products.

Detection and quantification of soymilk in cow–buffalo milk using Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR–FTIR)

Milk consumption is steadily increasing, especially in India and China, due to rising income. To bridge the gap between supply and demand, unscrupulous milk vendors add milk-like products from vegetable sources (soymilk) to milk without declaration. A rapid detection technique is required to enforce the safety norms of food regulatory authorities. Fourier Transform Infrared (FTIR) spectroscopy has demonstrated potential as a rapid quality monitoring method and was therefore explored for detection of soymilk in milk. In the present work, spectra of milk, soymilk (SM), and milk adulterated with known quantity of SM were acquired in the wave number range of 4000-500cm(-1) using Attenuated Total Reflectance (ATR)-FTIR. The acquired spectra revealed differences amongst milk, SM and adulterated milk (AM) samples in the wave number range of 1680-1058cm(-1). This region encompasses the absorption frequency of amide-I, amide-II, amide-III, beta-sheet protein, α-tocopherol and Soybean Kunitz Trypsin Inhibitor. Principal component analysis (PCA) showed clustering of samples based on SM concentration at 5% level of significance and thus SM could be detected in milk using ATR-FTIR. The SM was best predicted in the range of 1472-1241cm(-1) using multiple linear regression with coefficient of determination (R(2)) of 0.99 and 0.92 for calibration and validation, respectively.

The effect of salt, extract of kinnow and pomegranate fruit by-products on colour and oxidative stability of raw chicken patties during refrigerated storage.

Use of extracts of kinnow and pomegranate by-products as source of natural antioxidant in salted chicken patties during refrigerated storage was evaluated. Five treatments viz., I. Control (meat), II.MS (meat + 2%salt), III. KRP (meat + 2% salt + 2% kinnow-rind-powder extract), IV. PRP (meat + 2% salt + 2% pomegranate-rind-powder extract), and V. PSP (meat + 2% salt + 2% pomegranate seed powder extract). Results showed that salt significantly (P < 0.05) reduced lightness and yellowness but increased chroma and TBARS values. The average increase in TBARS was significantly (P < 0.05) higher in MS (114%) and Control (108%) but lower in KRP (90%), PRP (81%) and PSP (73%). Lipid oxidation (TBARS) in salted meat during the storage was significantly reduced (P < 0.05) by KRP (39%), PRP (43%) and PSP (68%). Thus it was observed that addition of 2% salt accelerated the TBARS formation but inclusion of extracts of pomegranate and kinnow fruit by-products effectively counteracted this effect. The overall antioxidant effect was in the order of PSP>PRP>KRP. Further a significant (P < 0.05) negative correlation between total phenolics contents and TBARS values was also observed. Therefore, it was concluded that extracts of these fruit by-products have potential to be used as natural antioxidants to minimize the oxidative problems in poultry meat products.

Detection and quantification of anionic detergent (lissapol) in milk using attenuated total reflectance-Fourier Transform Infrared spectroscopy

Adulteration of milk to gain economic benefit is rampant. Addition of detergent in milk can cause food poisoning and other complications. Fourier Transform Infrared spectroscopy was evaluated as rapid method for detection and quantification of anionic detergent (lissapol) in milk. Spectra of pure and artificially adulterated milk (0.2-2.0% detergent) samples revealed clear differences in wavenumber range of 4000-500cm-1. The apparent variations observed in region of 1600-995 and 3040-2851cm-1 corresponds to absorption frequencies of common constituents of detergent (linear alkyl benzene sulphonate). Principal component analysis showed discrete clustering of samples based on level of detergent (p⩽0.05) in milk. The classification efficiency for test samples were recorded to be >93% using Soft Independent Modelling of Class Analogy approach. Maximum coefficient of determination for prediction of detergent was 0.94 for calibration and 0.93 for validation, using partial least square regression in wavenumber combination of 1086-1056, 1343-1333, 1507-1456, 3040-2851cm-1.

Tenderizing effect of blade tenderizer and pomegranate fruit products in goat meat

Toughness of goat meat is a major problem with regard to consumer acceptance. Keeping this in view a blade tenderizer was developed for tenderization of goat meat. Pomegranate fruit products were also explored for tenderization effect on goat meat. Tenderization of goat meat with pomegranate seed powder improved the textural properties marginally with slight adverse colour change and taste. Samples treated with PRP got lower score for colour in sensory evaluation and there was adverse effect on taste of treated meat. Blade tenderization and 4% PSP proved better for tenderization and were compared with control and 0.2% papain in goat meat chunks. The cooked samples treated with papain and blade incisions got better sensory scores and required lesser shear force compared to 4% PSP and control. Overall the papain treated meat was superior in terms sensory attributes followed by blade incision and PSP. The results suggested that the blade incisions can be used for tenderization of goat meat. Pomegranate seed powder maybe considered for mixing with other spices to marinate goat meat mainly for its beneficial effects.

Detection of aflatoxin M1 in milk using spectroscopy and multivariate analyses.

Aflatoxin M1 (AFM1), a potentially carcinogenic compound, is found in milk obtained from animals that consume contaminated feed. Spectra of bovine milk, spiked with AFM1 (0, 0.02, 0.04, 0.06, 0.08 and 0.1μg/l) were acquired using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometer. Spectra revealed significant differences among pure and AFM1 spiked samples in spectral regions 1800-650cm-1 and 3689-3499cm-1, which may be attributed to complex chemical structure of AFM1. Principal component analysis (PCA) showed clear clustering of samples (p⩽0.05). The models could successfully classify (>86%) and detect even 0.02μg/l AFM1 in milk (p⩽0.05) using SIMCA. AFM1 was best predicted in wavenumber range of 1800-650cm-1 with coefficient of determination (R2) of 0.99 and 0.98, for calibration and validation, respectively, using partial least square (PLS) regression. The study indicated feasibility of ATR-FTIR spectroscopy and chemometrics in rapid detection and quantification of AFM1 in milk.