Effect Of Various Processing Methods Research Articles

Effect of various processing methods on the numbers of Clostridium (Clostridia, Bacteria) in animal by-products

Clostridia are one of the largest genera of eubacteria living in water, soil, the intestines of humans and animals. The genus Clostridium includes both pathogenic and non-pathogenic species. Representatives of this genus occupy a leading position among all types of bacteria in producing a variety of toxins. Due to their ability to form spores, these microorganisms can survive in the most unfavorable conditions. Antibiotic-resistant Clostridia, which are released to the environment as part of farm animal manure, are of particular environmental danger. We have studied the influence of various treatment methods (aeration, acidification, and surfactant application) of the liquid fraction of pig manure effluents (ME) on the species composition and the numbers of Clostridia. Cl. septicum and Cl. perfringens were found to occupy a dominant position in the ME of manure storage baths. Both species are actively involved in the ammonification of organic compounds, releasing a wide range of volatile substances with an unpleasant odor into the environment. Most of the Clostridia were detected in biofilms formed on the surface of ME under anaerobic conditions. Such conditions are formed during storage of the liquid fraction in closed lagoons, which increases the environmental risks of the release of undesirable microorganisms into the environment. Round-the-clock aeration and acidification of ME to pH 5.5 reduce the numbers of Clostridia. Such conditions contribute to the formation of microorganism consortia with fungi to occupy a dominant position. Cl. difficile (32.52%), Cl. putrificum (31.62%) and Cl. septicum (30.72%) predominated in biofilms of acidified ME, whilst only Cl. difficile (69.98–95.26%) did in options with surfactants added. The largest relative numbers of pathogenic Cl. difficile (95.26%) were observed in the option with the addition of a cationic surfactant (benzalkonium chloride).

Effect of different processing methods on maize, sorghum and millet flours on nutritional couscous quality consumed in the Far North region of Cameroon

Maize ( Z. mays ), sorghum ( S.bicolor ) and millet ( P. miliaceum )) are staple cereal grains consumed in many part of the world as nutraceutical and for their nutritional and sensory properties. In Maroua town (Far North region of Cameroon) maize, sorghum and millet grains are the main staple food to prepare couscous, however they were subjected to various processing methods (PMs) such as soaking, crushing, grinding, sieving, roasting, fermentation and germination as well. While, still to date there was no information about their effects on couscous quality. Therefore, the present study aimed to evaluate the effect of soaking, crushing, grinding, sieving and their combination on nutritional couscous quality produced from various flours processed. Hence, starch, carbohydrates, soluble sugars (SS), fibre, proteins, amino-acids, density, water absorption capacity (WAC) and oil absorption capacity (OAC) were investigated. The results obtained showed significant (P < 0.05) effect of various PMs on couscous quality, however their effects varied in respect with cereal types used. The ash content and pH increased in most of couscous samples, while SS, fibres and starch increased in maize, sorghum and millet couscous with the exception of SS which decreased in maize (12.40–3.16 g/100 g) and sorghum (11.98–3.09 g/100 g). Carbohydrates, proteins and amino-acids increased in maize and sorghum couscous, while they decreased slightly in millet couscous. The techno-functional properties increased in maize, sorghum and millet couscous except WAC (4.07–3.53 g/g) and OAC (1.55–1.16 g/g) which decreased in millet couscous. The present study demonstrated that the effect of various PMs on couscous quality is highly significant (P < 0.05) and variations were explained by PCA (PC1 x PC2: 47.05%). The PMs such as soaking, crushing and sieving had significant (P < 0.05) effect on conscous quality, thus they can be applied in order to maximize couscous quality for potential health benefit for consumers. • Four processing methods and combinaison on maize, sorghum and millet on couscous quality were studied. • Carbohydrates, ash, proteins and amino-acids increased in maize and sorghum couscous. • WAC and OAC decreased in couscous millet compared to other samples couscous. • Effects of processing methods varied significantly even if its combined according to cereal types. • Processing methods improved almost physicochemical composition and technofunctional properties of couscous.

Influence of processing techniques on the protein quality of major and minor millet crops: A review

Millets have a distinctive protein composition comprising of high concentrations of essential amino acids with numerous health-promoting characteristics. Through various in vitro and animal research studies, a variety of millet-based bioactive peptides isolated from millets have given significant evidence of their health-improving properties. However, the processing technique significantly impacts the biological activity of these millet peptides. The amount, structure, and function of major and minor millet proteins are influenced by different processing techniques. Studies have demonstrated that germination and fermentation increase bioavailability, in vitro protein digestibility, and protein efficiency. Moreover, the innovative processing techniques viz: microwave, ultrasound, and high-pressure processing had a significant impact on structural and quality attributes of the millet proteins and their fractionation. The non-thermal processing ensured the modification of structure and stability with the enhancement of functionality of the millet protein. The present review has been designed to summarize the major health benefits of millet proteins and the effect of various processing methods on their quality attributes. The information provided in the review would play an important role in further research and development activities at the commercial scale governing the improvement in millet protein efficiency, modification, bioavailability, and in vitro protein digestibility by different processing techniques. Novelty impact statement This review summarized the recent research on the major health benefits of millet proteins and the influence of different processing methods on bioactive peptides from major and minor millets.

Nutrient profile and effect of processing methods on the composition and functional properties of lentils (Lens culinaris Medik): A review

AbstractGrain legumes or pulses, including lentil (Lens culinaris Medik), have gained increasing popularity among consumers and food processors in recent years. This trend has been driven by the consumers opting for plant‐based proteins and environmentally sustainable food sources. Global production of lentils has more than doubled since 2001 (from 3.15 to 6.58 million metric tons in 2020), which signifies the commercial importance of this nutrient‐dense legume. As per the USDA's nutrients data (2022), lentil contains 24.6% protein, 63.4% carbohydrates, 2.7% ash content, and 1.1% total fat. High amount of dietary fiber, slowly digestible starch and potassium, and low sodium in lentil align well with consumer choices for healthy foods. Many studies have reported on the health benefits of consuming lentils, especially being effective in reducing various health conditions, such as hypertension, cardiovascular diseases, diabetes mellitus, and cancer. The relatively higher protein and lower carbohydrates content of lentil compared with cereal grains can help in expanding the utilization of lentils and lentil‐based ingredients to develop new products. Combined with high dietary fiber, resistant starch, and bioactive polyphenolic content, the demonstrated nutritional benefits can fill the ever‐increasing demand for plant‐based proteins well beyond traditional consumption of lentils in developing countries. This article reviews the composition and nutrient profile of raw and processed lentils, effect of various processing methods on composition and nutrient profile, and health benefits of lentils.

Effect of Different Processing Methods on Quality, Structure, Oxidative Properties and Water Distribution Properties of Fish Meat-Based Snacks.

Snack foods are consumed around to globe due to their high nutrition, taste and versatility; however, the effects of various processing methods on quality, structure and oxidative properties are scare in the literature. This study aims to evaluate the effect of various processing methods (frying, baking and microwave cooking) on quality, structure, pasting, water distribution and protein oxidative properties of fish meat-based snacks. The results showed that the frying method induced a significantly (p < 0.05) higher expansion than baking and microwave methods. Texture in terms of hardness was attributed to the rapid loss of water from muscle fiber, which resulted in compact structure and the increased hardness in microwave cooking, whereas in frying, due to excessive expansion, the hardness decreased. The pasting properties were significantly higher in baking, indicating the sufficient swelling of starch granules, while low in microwave suggest the rapid heating, which degraded the starch molecules and disruption of hydrogen bonds as well as glycosidic linkage and weakening of granules integrity. The water movement assessed by Low Field Nuclear Magnetic Resonance (LF-NMR) showed that frying had less tight and immobilized water, whereas microwave and baking had high amounts of tight and immobilized water, attributing to the proper starch-protein interaction within matrix, which was also evidenced by scanning electron microscopy (SEM) analysis. The protein oxidation was significantly (p < 0.05) higher in frying compared to baking and microwave cooking. The findings suggest the endorsement of baking and microwave cooking for a quality, safe and healthy snacks.

Opioid Peptides: An Overview of Functional Significance

Bioactive peptides have been reported to exhibit opioid-like activity and are termed as opioid peptides. Either these are produced within the human body or they are derived from certain food sources (milk, cereals, vegetables, meat, poultry etc.), the former being endogenous opioid peptides and the latter are the exogenous opioid peptides. The opioid peptides perform a wide range of biological functions including neuromodulation, hormone-like function, analgesia, sedative effect, sleepiness, anti-hypertensive effect, ACE-inhibitory activity and many more. However, also possess adverse effects such as depressive effect, development of alcoholism, inflammation, apnea, autism and even death in rare cases. The effect of various processing methods and techniques on the opioid peptides requires further exploration. This is a unique and comprehensive review that will explore the opioid peptides, their types, sources, distribution and mechanism of action as well as the health effects.

Effect of Processing Methods on the Nutritional Value of Canavalia ensiformis Jack Bean Seed Meal

The present study was undertaken to analyze the effect of various processing methods. Raw, Boiled, Toasted, Soaked and Fermented methods were applied on Canavalia ensiformis Jack bean seed meals to determine their nutritional compositions. The applied methods were found to improve the protein content (30%-36.60%), lipid (5.85%-9.23%), fiber (3.25%-6.35%), ash (3.5%-5.32%), Nitrogen-free extract (38.79%-46.21%). There was an increase in the mineral composition with processing methods; potassium, calcium and sodium were the most abundant macro minerals in Canavalia seed meal. There was also an increase in the essential amino acids of the processed minerals. Methionine content was increased due to fermentation (2.12 g/100 g) as compared to the raw (0.81 g/100 g). Vitamins A (1425.32-6124.56 IU/100 g), B1 (0.15-0.32 mg/100 g), B3 (0.06-0.21 mg/100 g), B6 (0.03-0.19 mg/100 g), C (7.54-25.65 mg/100 g) and D (0.36-0.53 mg/100 g). There was a reduction in vitamins content from boiled and toasted methods. Fatty acids: Capric (0.002-0.0035 g/100 g), Lauric (0.003-0.004 g/100 g), Myristic (0.004-0.006 g/100 g), Palmitic (0.015-0.023 g/100 g), Stearic (0.013-0.019 g/100 g), Oleic (0.016-0.021 g/100 g), linoleic (0.024-0.039 g/100 g) and Arachidic (0.003-0.006 g/100 g). The toasted and fermented method gave the bestprocessed methods. Knowledge gathering and exploration of nutritionally balanced unconventional legumes would enhance food and nutritional security.

Effect of Hydrogen Dioxide Treatment on the Osteogenic Potential of Duck-beak Bone-derived Natural Bioceramic Microparticles.

As an alternative material to the autogenous bone, duck-beak bone particle for bone substitute have been attracting great attention due to their biological properties. To deliver the most favorable outcome of medical treatment, it is essential to study the effect of various processing methods of the duck-beak bone. In this study, we compared the two deproteinizing agents for manufacturing duck-beak bone. Group 1 was treated by a conventional chemical agent (ethylenediamine) and Group 2 by hydrogen dioxide (H2O2). In vitro and in vivo experiments were conducted in parallel to compare the cytocompatibility and osteogenic capability between two processing methods. For in vitro tests, human adipose-derived mesenchymal stem cells (hAD-MSCs) were planted onto each sample and their attachment and growing were evaluated. For in vivo biocompatibility and osteogenic properties, the samples were applied on the critical-sized calvarial bone defect of rats. Group 2 showed significantly higher cell attachment but Group1 showed slightly higher cell proliferation. In in vivo tests, all groups have shown biocompatibility and increased level of osteogenic potential. However, Group 2 had significantly higher bone regeneration (p<0.05). This experiment confirmed that H2O2 can be an optimal processing method for duck-beak bone particle.

Effect of processing methods on compositional evaluation of underutilized legume, Parkia roxburghii G. Don (yongchak) seeds.

The present study has been undertaken to analyze the effect of various processing methods like (i) soaking followed by autoclaving with (a) ash, (b) sodium bicarbonate, (c) sugar and (d) water; (ii) dry heating and (iii) fermentation on nutritional and antinutritional components of under-utilized tree legume Parkia roxburghii. The applied methods were found to enhance the protein (15-36%) and lipid content (11-69%) and to decrease the other proximal components. All the methods significantly reduced the antinutrients viz. condensed tannins, phytate, saponins, trypsin inhibitors, chymotrypsin inhibitors and lectins. Exceptionally, increased content was documented on total phenolics (117-207%) and tannins (171-257%). These reduced antinutritional loads have led to an increase in protein (9-20%) and starch digestibility (75-254%). Fermented kernels, the best processed form showed characteristic leguminous pattern for content and composition of amino acids, fatty acids and minerals. So knowledge gathering and exploration of nutritionally balanced under-utilized legumes would enhance food and nutritional security.

Effect of Various Processing Methods on the Pasting and Functional Properties of Aerial Yam (Dioscorea bulbifera) Flour

Effect of Various Processing Methods on the Pasting and Functional Properties of Aerial Yam (Dioscorea bulbifera) Flour

The effect of thermal processing on protein quality and free amino acid profile of Terminalia catappa (Indian Almond) seed.

The study examined the effect of various processing methods- boiling, drying and roasting- on the in vitro and in vivo protein digestibility and free amino acid profiles of Terminalia catappa seed. Moisture and crude protein of the various samples were determined. In vitro protein digestibility was determined after pepsin digestion. For the in vivo experiment, defatted T. catappa based diet was fed to 3weeks old Wistar rats for 4weeks and compared with animals maintained on casein based and nitrogen- free diets. The biological value (BV), net protein utilisation (NPU) and protein efficiency ratio (PER) of the diets were determined. Free amino acid composition was carried out using thin layer chromatography. Moisture was highest in the boiled T. catappa seed (8.30 ± 0.00%). The raw, roasted and dried seeds had 5.55 ± 0.07, 3.88 ± 0.22 and 3.75 ± 0.07% respectively. Crude protein was 19.19, 18.89, 17.62 and 16.36% in the dried, roasted, boiled and raw seeds respectively. Roasted T. catappa seed had the highest in vitro protein digestibility with 37.52%, while the dried, boiled and raw samples had digestibility values of 27.57, 27.07 and 24.45% respectively. All nine essential amino acids were present in T. catappa in high concentrations except methionine and tryptophan. Glutamate was present in the highest concentration. Also, free amino acids were higher in the processed seeds compared to the raw seed. Animals fed T. catappa diet compared favourably with the casein group, thus indicating that the protein is of good quality.

Antioxidant Activity in Two Pearl Millet (Pennisetum typhoideum) Cultivars as Influenced by Processing.

Research on the effect of processing on the retention of bioactive components with potential antioxidant activity is gaining importance. The objective of this investigation was to evaluate the effect of various processing methods (milling, boiling, pressure cooking, roasting and germination respectively) on the antioxidant components as well as the antioxidant activities in the commonly used pearl millet cultivars—Kalukombu (K) and Maharashtra Rabi Bajra (MRB). The methanolic extracts of processed pearl millet flours were analyzed for 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power assay (RPA) and ferric reducing antioxidant power (FRAP) assays respectively. The samples were also evaluated for tannin, phytic acid and flavonoid content which was then correlated with the antioxidant activity assayed using three methods. The results indicated that the bran rich fraction showed high antioxidant activity (RPA) owing to high tannin, phytic acid and flavonoid levels. Heat treatments exhibited significantly (P ≤ 0.05) higher antioxidant activity (DPPH scavenging activity and RPA) reflecting the high flavonoid content. Processing did not have any significant effect on the FRAP activity of pearl millet. The data on the correlation coefficient suggests that DPPH radical scavenging activity and reducing power assay in the K variety was largely due to the presence of flavonoid content, however in MRB, no relationship was found between antioxidant activities and antioxidant components.

Effect of Indigenous Processing Methods on Phenolics and Antioxidant Potential of Underutilized Legumes Acacia auriculiformis and Parkia roxburghii

AbstractThe effect of soaking followed by autoclaving in various solutions such as ash, sodium bicarbonate, palm sugar and water; dry heating; and fermentation on antioxidant power of two underutilized legumes Acacia auriculiformis and Parkia roxburghii has been investigated. In comparison with the unprocessed ones, processed seed extracts of Acacia and Parkia have been registered with 1–29% loss and 4–29% gain of phenolics, respectively. The processing methods enhanced the reducing power (13–92%) and free radical‐scavenging activity on synthetic radicals (2,2′‐diphenyl‐1‐picryl‐hydrazyl [DPPH]: 5–31%; and 2,2‐azinobis [3‐ethyl benzothiazoline‐6‐sulfonic acid] diammonium salt [ABTS]: 1–80%). However, significant reductions were noticed on scavenging activity of biologically relevant radicals (hydroxyl: 8–87%; superoxide anion: 4–85%; and nitric oxide: 14–80%) and peroxidation inhibition (10–48%). Invariably, all the processing methods enhanced the protection capacity on erythrocytes and DNA against oxidative insults. Among the processing methods, dry heating and fermentation retained the antioxidant potential in A. auriculiformis and P. roxburghii, respectively, than other methods.Practical ApplicationsLegume seeds, the protein‐rich plant sources, have to be cooked/processed before consumption so as to eliminate their native antiphysiological factors and to enrich their nutritional values. Daily consumption of legumes in preventing lifestyle diseases due to its phytoceuticals is best valued in the present scenario. Hence, this study demonstrated the effect of various processing methods on phenolics and the antioxidant capacity of two underutilized legumes Acacia auriculiformis and Parkia roxburghii by an array of in vitro tests. Knowledge on these types of locally available plants could provide useful data for the development of potential future crop resources for various food and feed applications and further reduces the pressure on conventional/cash crops.

Effect of Various Processing Methods on Quality of Mackerel (Scomber scombrus)

The effects of combinations of processes (hot smoking, marinating, vacuum packing and seasoning with dill (Anethum graveolens) on the quality parameters of mackerel (Scomber scombrus) stored at 4 °C were investigated in terms of sensory, chemical (total volatile basic nitrogen [TVB-N], thiobarbituric acid [TBA], peroxide value [PV], free fatty acids [FFA]) and microbiological parameters (total viable count [TVC], coliform, Escherichia coli, Staphylococcus aureus) during 9 months of storage. Sensory quality of smoked mackerel marinates with or without dill leaves (Group A, Group B, respectively) decreased throughout storage period. However, at the end of storage period, both the products were still acceptable by the panellist. At the beginning of storage, the initial TVB-N values were 24.14 mg/100 g and showed fluctuations during storage period. TBA values significantly increased (p < 0.05) for both products during storage period. PV showed fluctuations. FFA increased gradually from 2.46 to 7.33 (expressed as % of oleic acid) for Group A and from 2.57 to 6.90 for Group B at the end of storage period. Coliform, E. coli and S. aureus were not detected during storage period. TVC remained lower than the acceptability limit of 106 log CFU/g at the end of storage period. The results of this study suggest that shelf life of both products was 9 months and also the combination of hot smoking, marinating, vacuum packing and seasoning led to high-quality food item and was found to be effective in controlling the growth of bacteria and biochemical indices.

EFFECT OF VARIOUS PROCESSING METHODS ON THE LEVELS OF ANTINUTRITIONAL CONSTITUENTS AND PROTEIN DIGESTIBILITY OFMUCUNA PRURIENS(L.) DC. VAR.UTILIS(WALL. EX WIGHT) BAKER EX BURCK (VELVET BEAN) SEEDS

ABSTRACT In the present study, the effect of various processing methods on the levels of antinutritional compounds and in vitro protein digestibility (IVPD) of seeds of a potential South Indian under-utilized legume, Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck (velvet bean), was investigated. Among the various postharvest treatments employed, soaking the seeds in NaHCO3 solution followed by autoclaving appears to be more effective in reducing the maximum levels of various antinutritional compounds, such as total free phenolics (74–81%), tannins (74–83%), L-3,4-Dihydroxyphenylalanine (L-Dopa) (69–83%), phytic acid (85–86%), oligosaccharides such as raffinose (73–79%), stachyose (73–82%) and verbascose (71–75%), hemagglutinating activity (70–84%), trypsin inhibitor activity (72–81%) and α-amylase inhibitor activity (73–82%), and also results in significant improvement of IVPD (15–23%) of both the white and black seeds of velvet bean. Adoption of such viable processing method will enhance the utilization of velvet bean seeds as an alternative/additional protein source for both human beings and animals. PRACTICAL APPLICATIONS The recent research trend has been directed to evaluate the under-utilized legume seeds as an alternative protein source to meet the protein requirements of increasing human population and expanding livestock industries. In this context, the velvet bean (Mucuna pruriens[L.] DC. var. utilis) seeds receive more attention as alternative/additional protein source. Although the velvet bean seeds were found to contain high content of protein, carbohydrates and other nutrients, their utilization as food was restricted largely because of the presence of high concentrations of various antinutritional compounds. Hence, in the present study, various common postharvest processing methods were employed to remove/reduce the levels of antinutritional compounds of velvet bean seeds. From the present investigation, a cost-effective and viable processing method has been identified for the versatile utilization of velvet bean seeds as an alternative source of protein in the diets of both human beings and animals.

Effects of Processing Methods on the Proximate Composition and Momordicosides K and L Content of Bitter Melon Vegetable

Bitter melon (Mormodica charantia L.) has been associated with health benefits such as hypoglycemic, antiatherogenic, and anti-HIV activities. The vegetable, however, has an unpleasant bitter taste. The purpose of this research was to establish the effect of various processing methods on the moisture, lipid, and protein content of the Sri Lanka variety of bitter melon and to determine the effect of the processing methods on momordicosides K and L contents. The processing methods used were frying, blanching, sun drying, oven drying, freeze drying, and bitter masking with five different commercial bitter masking agents. Moisture, lipid, and protein analyses were done using standard AACC methods. Drying decreased moisture content from 92% to 9.5-10.2%. Frying lowered moisture content to 0.8% while increasing lipid content from 3.6 to 67%. Protein content remained unaffected by treatments. A liquid chromatography-electrospray ionization-mass spectrometry (LC/ESI/MS) method was used to identify momordicosides K and L in methanolic extracts of fresh and processed samples. Only extracted ion chromatographs for blanched bitter melon and bitter melon with MY 68 agent showed the absence of momordicosides K and L.

Effect of Processing of Sword Beans (Canavalia gladiata) on Physicochemical Properties of Starch

AbstractThe effect of various processing methods on physico‐chemical properties of sword bean starch was studied. Seed grits and flour were cooked with and without soaking, wet‐autoclaved, and roasted. The changes in starch associated with these processing methods were studied by observing changes in granular structure, water solubility index, water absorption index, molecular size distribution and the degree of gelatinization estimated by differential scanning calorimetry. Intact, ungelatinized starch granules of raw and dry‐heat treated samples were observed under the light microscope. The starch granules were elliptical in shape and had an average length and breadth of 37–40 μm and 27 μm, respectively. Wet‐processed samples had the lowest water solubility, higher water absorption and lower gelatinization enthalpies than the raw bean flour, whereas the dry heat‐treated samples showed higher water solubility and higher gelatinization enthalpies. The starch molecular size distribution pattern showed a higher amount of high molecular size carbohydrates in dry heat‐treated samples and a large fraction of intermediate molecular size carbohydrates in the wet‐processed samples. The low molecular size carbohydrate content was low in wet‐processed samples where processing was done with excess water.

Effect of Various Processing Methods on the Physical Properties of Cooked Rice and on in vitro Starch Hydrolysis and Blood Glucose Response in Rats

AbstractThe effects of various cooking methods on the physical and structural properties cooked rice, on the in vitro hydrolysis of the contained starch and on blood glucose response in rats were investigated. At optimum cooking state, a larger filamentous network was formed and most of the starch granules were fragmented, furthermore the samples heated by microwave and electric cooker showed a more compact structure compared to those treated in an autoclave or stone pot. The highest degree of gelatinization (DG) was observed in the sample treated in an autoclave (75.2%), followed by stone pot (71.1%), electric cooker (66.9%) and microwave oven (64.6%). The highest firmness (3.49 N) was observed in cooked rice heated by microwaves and no significant differences (p &gt; 0.05) were found between the other samples. All cooked rice samples showed increased pasting temperatures and decreased peak viscosity compared to those of raw rice flour. The starch hydrolysis rates and their kinetic constants of cooked rice samples increased with increase in DG, and relatively higher values were observed in samples treated in the autoclave and stone pot. There was a significant difference in the blood glucose content depending on cooking methods, and the highest glucose level was observed in the sample heated by autoclaving.

Chemical evaluation of the seeds of Milletia obanensis

A study was conduced to evaluate the nutritional potential of Milletia obanensis “Odudu” as a possible food or feedstuff and to assess the effect of various processing methods on its nutritional quality. Results of proximate analysis showed that the raw seeds contained 26.7% crude protein, 23.5% ether extract, 3.47% crude fibre, 4.37% ash and 42.0% nitrogen free extract. The protein was well supplied with essential and non-essential amino acids, though the values were low when compared with popular seed legumes. Minerals were in fair supply: P 3.10, Mg 92.30, K 45.25 and Fe 2.20 mg/100 g. Processing methods significantly ( p<0.05) affected the nutritional composition. While autoclaving, boiling and toasting (heat treatment) increased the protein content, it reduced the levels of anti-nutritional factors-phytate, tannins, oxalates, cyanogenic glycosides and (slightly) saponin. Thus, it was concluded that M. obanensis seeds, if properly processed, could serve as livestock feed or food for man.

EFFECT OF PROCESSING ON AMYLASE AND PROTEASE INHIBITOR ACTIVITY IN TROPICAL TUBERS

The effect of various processing methods on amylase, trypsin and chymo-trypsin inhibitory activities in tubers of Colocasia esculenta (taro), Xanthosoma sagittifolium (tannia), Solenostemon rotundifolius (Coleus, Chinese potato), Dioscorea esculenta (lesser yam) and Amorphophallus paeoniifolius (elephant foot yam) was studied. Among the different methods, frying was the most effective method of eliminating enzyme inhibitors from tubers. When cooked by boiling, partial retention (30 to 60%) of enzyme inhibitory activity was observed in certain tubers. Further reduction in inhibitory activity was observed in baked/pressure cooked tubers. The study indicated that processing decreased the inhibitor content significantly and the reduction of inhibitory activity was brought about by heat inactivation.