Current Nutrition & Food Science - Volume 11, Issue 3, 2015

Omega 3 polyunsaturated fatty acids (PUFAs) are essential fatty acids (FAs) with positive effects on treatment and/or prevention of several diseases. Enhancement of omega 3 PUFA content in diet has led to a number of strategies aiming to modify the content of such FAs in fats and oils. Enzymatic processing of omega 3 PUFA oil is preferred over chemical ones, due to the mild reaction conditions used, and more importantly, due to the lipase specificity, since the position as well as content of omega 3 PUFAs in lipid molecules is of importance from the point of bioavailability. In this review, the recent developments in the field of enzymatic modification of oils rich in omega 3 PUFAs have been examined. Several different products, namely structured lipids with a variety of FA compositions, omega 3 PUFA concentrates, phospholipids and phenolic lipids, have been discussed from the point of process technology as well as possible applications.

Marine lipids are enriched with omega-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Omega-3 fatty acids are important membrane lipids and have many recognized health benefits, the bioavailability of these fatty acids can therefore be important for achieving the beneficial healthy effects. As important membrane lipids, the incorporation and depletion kinetics of EPA and DHA in biological membranes have been found to be different, DHA was depleted slowly from both erythrocyte and plasma membranes due to the slow re-synthesis of DHA in the body. The bioavailability of omega-3 fatty acids has been reported to be affected by several factors; among the important factors were the digestion and absorption processes of omega-3 containing lipids in the gastrointestinal tract. Both lipid structures and food structures can affect the bioavailability of omega-3 fatty acids. Human studies have shown that the relative bioavailability of omega-3 fatty acids from fish oil (triglyceride formulation) was similar to that from fish, whereas lower relative bioavailability was observed from fatty acid ethyl ester (FAEE) formulation in comparison with other lipid formulations. In vitro studies provided a mechanistic understanding on the varied bioavailability caused by different lipid structures, the lower relative bioavailability of omega-3 fatty acids from FAEE formulation was closely related to the slower digestion rate of FAEE. Microencapsulated fish oil has often been used as a food additive because of its better chemical stability; studies showed that microencapsulation did not affect the bioavailability significantly. Even though food structures also affect the digestion and absorption of omega-3 containing lipids, several studies have shown that long-term intake of fish oil and food products enriched with fish oil is an efficient way to provide EPA and DHA.

The awareness of health benefits of marine lipids with a high content of omega-3 poly unsaturated fatty acids from fish and algae oil has led to an increased intake as oil and in products. However, these lipids are highly susceptible to lipid oxidation, which results in the formation of undesirable off-flavours and gives rise to unhealthy compounds such as free radicals and reactive aldehydes. Necessary prerequisites for successful development of omega-3 enriched products are that the oil used for enrichment is of a high quality and low in oxidation products and that oxidation of the lipids is prevented both during production and storage. In complex products, lipid oxidation and antioxidant mechanisms are very complex, due to the many factors that can influence the rate and extent of lipid oxidation. In order to obtain and maintain a good quality and oxidative stability of omega-3 oil and enriched foods, oxidation may be minimised by optimising by both intrinsic (physico-chemical) and extrinsic factors. Intrinsic factors are e.g. addition of antioxidants, choise of emulsifier and droplet size. Extrinsic factors, such as exposure to light, high temperature and oxygen, cause increased oxidation. As processing will often cause extra oxidative stress to the omega-3 oil, extrinsic factors are especially important to consider during processing. Due to the complexity of multiphase foods, it is very difficult to predict the oxidative stability and therefore the behaviour and efficacy of antioxidants in omega-3 oil enriched products and optimal composition and processing conditions must be evaluated for each product.

This study aimed to investigate the total phenolics content (TPC), capacity of scavenging radicals (RSA), chain-breaking capacity (CBA), hydrogen peroxide scavenging capacity (HPS) and the capacity of reducing oxides or reducing capacity (RC) of Jamaican jujube (coolie plum) (Ziziphus mauritiana) during four different maturation and ripening stages. TPC decreased significantly during the four ripening stages but the decrease was more significant during stage 4. RSA of stage 1 and 2 reacted faster and showed the most effective DPPH radical scavenging activity, while stage 4 showed the lowest reaction and was the less effective DPPH radical scavenger. CBA increased during stage 2, decreased significantly during stage 3, then increased again to a value closer to that observed at stage 2. RC increased significantly during stage 2, and then decreased during stage 3 and stage 4. HPS showed similar pattern to the reducing capacity and was quite high during stage 1, but showed a decrease during the stage 3 and increased again during stage 4. Conclusively, the results of this investigation showed interesting antioxidant and scavenging properties of Jamaican jujube (coolie plum) extracts, which could be an interesting health-promoting especially when processed for juice.

Background: Food insecurity has been associated with diverse health consequences for children in developed and developing countries, and the interest on food insecurity prevalence and consequences on children have been globally increased. Children academic performance is influenced by many factors, such as general health status, nutrient intake, cognitive development and psychosocial stimulation. Aim: To estimate 1) the prevalence of food insecurity among Jordanian children from public schools in North of Jordan, 2) the impact of food insecurity on academic performance, 3) the prevalence of food insecurity among the participants according to their socio demographic characteristics. Method: A random sample of 679 children (221 males and 458 females) aged 12 to 16 years completed the study. Data were collected using an interview-based questionnaire. The interview was conducted by a trained research assistant. Data about the students’ demographics were collected (age, gender, housing status and family income). Academic performance was measured by children’s school grades of the past year. Result: The prevalence of mild and severe food insecurity was 15% and 7% respectively. Food insecurity was associated with student’s gender, housing status and family income. After adjusting for the covariates, children food insecurity significantly associated with their academic performance. Food insecurity is prevalent among children in Jordan and negatively influences school performance.

Lactose intolerance is the syndrome of lactose mal-digesters in which consumption of lactose containing dairy products may induce symptoms like abdominal bloating, flatulence, diarrhoea, abdominal pain and discomfort. These symptoms result from bacterial fermentation of undigested lactose present in the colon. This is diagnosed by patients ingesting a standard dose of lactose after fasting and measuring breath hydrogen. Elevated breath hydrogen levels are a result of this bacterial fermentation taking place in the colon. Presently the management of lactose intolerance is by reducing lactose exposure. This is done by avoiding milk and milk-containing products or by drinking milk in which the lactose has been pre-hydrolyzed with lactase.

Confusion exists among consumers regarding the health benefits and safe usage of organic food. Published literature of organic food lacks homogeneity of toxicity and contamination. A methodical approach was used to explore and understand the status of various types of organic food and also compare them with conventionally grown food. Organic food was found nutritionally rich in minerals like calcium, potassium, magnesium, iron and sodium. Level of environmental contaminants like cadmium, nickel, lead, chromium and zinc was higher in organic food samples. Bacterial contamination risk was slightly higher in food cultivated by conventional farming as compared to organic food samples. Conventionally grown turmeric showed the presence of pesticides above the permissible limit of 0.1mg/kg. Organically grown food also showed traces of pesticide residues but were within the permissible limit. The present study agrees to the consumer perception that organic food is safe and healthy.

The effect of different thawing methods on three haskap berry (Lonicera caerulea L.) varieties, Tundra (T), Berry Blue (BB) and Indigo Gem (IG), was investigated. Methods included thawing the frozen berries at room temperature (25 ± 2 °C), refrigerated temperature (4 °C) and using a microwave oven. All the berry varieties were analyzed for their total phenolic content (TPC)/total reducing capacity (TRC), total anthocyanin content (TAC) and antioxidant potential (DPPH˙ radical scavenging activity). The TPC/TRC, TAC and DPPH˙ scavenging activity ranges in the fresh fruits were 6.17-8.42 mg GAE/ g FW, 4.49-6.97 mg C-3-G E/ g FW, and 78.70-89.55 %, respectively. Frozen storage for six months followed by consequent thawing at the standard conditions (room temperature) caused 35.85-44.73, 32.14-53.23, and 26.28-29.57 % reductions in the TPC/TRC, TAC, and DPPH˙ scavenging activity, respectively. The highest reduction occurred in the Berry Blue variety followed by that of Indigo Gem. Refrigerated thawing did not significantly improve the retention of phenolic compounds and anthocyanins. Microwave thawing could be achieved in significantly shorter time (17.31 min) as compared to room temperature (12.00 h) and refrigerated thawing (22.00 h) and could significantly improve the retention of phenolics, anthocyanins and antioxidant potential. The corresponding reductions in the TPC/TRC, TAC, and DPPH˙ scavenging activity of different varieties ranged from 24.97%-39.87%, 18.92%-47.22%, and 21.39%- 27.29 %, re-spectively. Thus, further investigation into the industrial application of microwave thawing is recommended to maximize the retention of bioactive compounds in products manufactured from frozen haskap berries.

This study investigated the effect of flavoring on the nutritional values of the potato chips. A comparative analysis of six different flavors of potato chips was performed to understand the differences in their total fat, sodium, carbohydrate, crude fiber, cholesterol, protein content and fatty acid (FA) profiles. Our results showed that there was a significant difference in the proximate content among the various flavors of the chips analyzed. The sodium, moisture and FA contents varied significantly and also influenced the energy yield of potato chips. Palmitic acid (4-7.4%), stearic acid (3.4-3.8%), linoleic acid (56.2-59.4%) and oleic acid (28.4-30.4%) were the most significant FAs. The different flavors of the chips showed high content of unsaturated fatty acids. On comparing the individual FAs from the potato chips samples with different vegetable oils, no similarity with single oil could be found. The pattern of the FA composition clearly indicated the use of a combination of sunflower oil, soybean oil and corn oil as the major components of the oil used for frying these chips. It can be concluded that both sodium and FA play an important role in imparting flavor and taste to potato chips.

Rice bran which is an industrial cereal processing waste/by-product has great economic potential towards developing nutraceuticals and functional foods to combat life style related diseases because of several health beneficial biomolecules and micronutrients present in it. Utilization of food processing waste or byproducts through sustainable development into new food has been regarded as a potential thrust area in recent years. To exploit rice bran commercially in this area, it is of utmost importance to stabilize freshly milled rice bran to enhance its shelf-life as it develops rancidity within few hours of its milling due to the action of lipase and lipoxygenase (LOX) enzymes present in it. Hence stabilization of freshly milled rice bran through inactivation of these enzymes has been a subject of much interest to food chemistry researchers. Considering the importance of rice bran for its potential use as nutraceuticals, food supplement and functional food, coupled with green technology associated with microwave (MW) energy in food science and technology, we report here an expedited and convenient stabilization process of rice bran with special reference to some of the indigenous rice cultivars grown abundantly in North East India situated in the Eastern Himalayan Range, which is one of the global hot spots of biodiversity. The work further highlights the efficacy of MW energy in deactivating lipase and lipoxygenase enzymes present in rice bran to give it longer shelf-life for its potential exploitation as nutraceuticals and food supplements.