Takenori Maruyama

Thermostability of Silicone Oil Evaluated by Thermogravimetric Method

The thermostability of silicone oil and antioxidation effects of lard containing silicone oil were evaluated by thermogravimetric (TG) and Rancimat methods.In programmed TG for silicone oil alone, the initial temperature of weight loss shifted to the higher temperature side with increase in viscosity. In programmed TG of lard samples to which silicone oil had been added, slight elevation in the initial temperature of weight loss was noted for several samples.For isothermal TG, thermostability evaluated based on the initial time of decomposition for lard samples to which a silicone oil had been added was found similar to oxidative stability measured by the Rancimat method. Antioxidant effects determined by the two methods failed to show any definite relationship with the type or amount of silicone oil added.

Thermostability of Synthetic Antioxidants

By programmed thermogravimetry (TG), weight loss of 8 synthetic antioxidants was examined, and thermostability was determined from initial temperatures based on TG and decomposition time at 5 % by isothermal TG. Antioxidant content in residual substances was determined at 25 % weight loss by TG. The results obtained are summarized as follow : 1) For programmed TG, curves for synthetic antioxidants showed characteristic weight loss patterns depending on the type of antioxidant. Weight loss patterns were not influenced by atmospheric gas used (air and nitrogen).2) At 25 % weight loss by TG, phenolic antioxidant content in residual sabustances exceeded 90 % in both gases. Gallate content was less than that observed for phenolicis.3) Synthetic antioxidant thermostability increased in the order of NDGA>DG>OG>PG>THBP>TBHQ>BHA>BHT as determined from TG data.

Some Properties of Commercially Available Margarines and Cooking Fats in Germany

Commercial margarines, cooking fat and lard in Germany were assessed for quality, using 16 brands of margarine (including 4 of high linoleic type), 9 of low fat spread (including 4 of high linoleic type), 4 of dairy spread (compound type, 2 ; low fat butter, 2), 11 of cooking fat and 8 of lard, totaling 48.1) Lipid and water content averaged 80.0 and 19.4% in margarine, while 39.5 and 56.8% in low fat spread, respectively. The latter had about half calories of the former. Sorbic acid and stabilizers of emulsion were added to the low fat spread.2) Almost all margarine samples were fortified with vitamins A and D3, and vitamin B6, was also found in some cases. To all high linoleic products, α-tocopherol was added, and tocotrienols were detected in 6 brands of margarine, indicating blending palm oil to possibly be present.3) Cholesterol was detected only as a trace in products labelled vegetable oil on tha package, but Δ7-stigmastenol and avenasterol were detected in greater amounts in high linoleic products than in others.4) Since high linoleic margarines comprised of 64.351. 1% (57.7% in average) of c, c-18 : 2 fatty acid, and contained less trans fatty acids, they were considered “zero-trans” products. The ratios of α-tocopherol (mg) /polyunsaturated fatty acids (g) in these ranged from 1.45 to 0.63 (1.00 in average), indicating α-tocopherol to be sufficiently present.5) Various types of composition were present in cooking fat, most lard product were characteristically present in addition to onion and spices.6) SFC curves indicated the high linolleic type of margarines to be softer than others in the low temperature region. The dairy spread showed more SFC in the low temperature region, but less SFC in the higher region than margarines. SFC in cooking fat varied considerably according to type, and lard showed a SFC curve with a unique feature of a wide melting range.

Qualitative Characteristics of Recent Fat Spread for Household Use

The qualitative characteristics of recent household fat spreads, whose production is rapidly increasing, were investigated by measuring various chemical and physical parameters of 8 brands of fat spread (vegetable oil type 7; milk fat blend type 1) and 7 brands of seasoning fat spread (cheese containing type 5; spice containing type 2).1) From data on general and nutritional components, in fat spreads, a brand of a vegetable oil type was shown to contain 39.4% lipids, meeting the international standard of “minarine”, but most types commercially available contain 70% or more lipids. Thus, the energy of household fat spreads is 1550% less than that of household margarine. Also, all brands of fat spreads except 3 were fortified retinol at the same level as household margarine.2) Analytical results on sterols, tocopherols and fatty acids in the fat spreads showed the vegetable oil type to be made from a high linoleic acid blend of vegetable oils only, but the spice containing type to contain animal fat, probably hardened fish oil. Also, 4 brands of fat spreads appeared to contain palm oil at low levels since trace amounts of tocotrienols were detected. Furthermore, tocopherol content in the vegetable oil type was relatively high. The content of α-tocopherol was markedly higher than that in any other type.3) According to the curves of hardness index, oil-off values and solid fat content (SFC) for different types of fat spreads, the vegetable oil type tended to oil off with more difficulty and showed more SFC than high linoleic soft margarine, while the hardness was almost the same. A similar tendency was observed between each of the other types of fat spreads and the common soft margarine. Thus possibly household fat spread can be manufactured by directing more attention to its forming ability, since it contains more water than margarine.

Seasonal variation of tocopherols in different tissues of carp, and their relationships to vitamin A and D.

Seasonal variation of tocopherol (Toc) contents in several tissues of carp was investigated on the cultured fish caught in March, July and December and the wild one in March by high performance liquid chromatography. Also, the contents of vitamin A and D in the same tissue were compared with Tocs.1) In the composition of Tocs in carp, the percentage of non-α-Toc in the tissue rich in fat was higher than that in the lean tissue.2) The contents of Tocs in carp tissues had a tendency to increase with the gonadial development, and especially the tendency was remarkable in the gonad and fatty tissue surrounding brain of the wild fish, which had the greatest gonad. In the above two tissues of the carp in March, corresponding to a gonadial developing season for spawn, significant differences in the contents of Tocs between male and female were observed, but such difference was not observedin any tissue of the carp in July and December, out season of spawning.3) The contents of vitamin A and D in tissues were suggested to have essentially no seasonal variation, but the contents of two vitamins in tissues of the cultured fish in March were generally lower than that of the other three groups.In any tissue of carp, no correlation between the content of Tocs and that of vitamin A or D was observed.

Determination of Benzoic Acid, Sorbic Acid and Dehydroacetic Acid in Margarine by High Performance Liquid Chromatography

A simple and rapid method was developed for the determination of benzoic acid, sorbic acid and dehydroacetic acid in margarine by high performance liquid chromatography (HPLC).A 1.0g sample of margarine in a 50ml centrifuge tube with 50ml of distilled water was warmed to an almost completely molten state, and shaken vigorously. The water layer was taken out and a portion of it was filtered through a 0.45μm pore membrane filter. The filtrate was injected into an HPLC column (4.6×50mm) packed with Unisil Q C18 (5μm). The column was eluted with a mixture of 0.03M sodium acetate-acetic acid buffer (pH 5.0)-methanol (4:1). The preservatives were detected with a UV-spectrophotometer set at 225nm.Average recovery of individual preservatives from margarine was more than 96%. The detection limits were benzoic acid 0.5mg/kg, sorbic acid 0.7mg/kg and dehydroacetic acid 1.0mg/kg. There is no substantial difference in the recoveries from margarine of these preservatives between the proposed method and the steam distillation-GC method.

Fractional Determination of Provitamin A in Chlorella Using High Pressure Liquid Chromatography

乾燥クロレラ中のプロビタミンAをTLC, CPCで分画し, 可視部吸収スベクトルおよびHPLC分析により検索, 同定した。 ついでHPLCを用いるこれらの分別定量法について検討した。1) TLCによりクロレラカロチノイドは9画分に分離したが, そのうちRfの高い3画分を標準カロチノイドと比較して, 順にα-, β-カロチンおよびluteinと同定した。 またCPCでもクロレラカロチノイドから吸着能の低い順にα-, β-カロチンおよびluteinが分離することを確認した。 なおそのうちluteinはクロレラカロチノイドの主成分であった。2) HPLCを用いるプロビタミンAの分別定量法を確立したが, この方法はけん化, 抽出およびHPLC操作から成っている。 なお本法により乾燥クロレラからさらに微量のクリブトキサンチンを検出した。3) 本法によるβ-カロチンの回収率は96.9%であり, 乾燥クロレラ試料を用いて行なった5回のくり返し実験によるα-, β-カロチンおよびクリプトキサンチンの平均値は9.89, 24.66および0.41mg/100gであり, 測定値の変動係数は2.30, 0.81および8.60%であった。なお本法による定量限界は4.01mg/100gであった。4) 37℃, 6か月間蛍光灯照射した乾燥クロレラ試料のα-, β-カロチンおよびクリブトキサンチン量は0.78～0.43, 1,58～1.09および0.02～0.01mg/100gであった。

Stability Tests of Household Margarine

To know a shelf-life of margarine, eleven kinds of household margarine were preserved at 5°C and the change of POV, AV and vitamin A content were investigated, together with sensual check. Besides, unwrapped samples of seven kinds were left in refrigerator and taking out for one hour every day, as a usual handling condition. In addition, as abnormal storage condition, similar samples were exposed to fluorescent light or left under sunlight.Results obtained were as follows:1) In the shelf-life test, only one sample of high linoleic type developed odor slightly after 12 months. All samples under usual handling condition were not developed any odor for 3 months. However, under fluorescent light, samples of high linoleic type developed abnormal odor within 2 to 5 days, and all samples under sunlight showed same tendency within 5 hours to 2 days.2) POV and AV were hardly changed during the shelf-life test and vitamin A was remained 97.8% (average) after 12 months.3) Under usual handling condition, POV was hardly changed and average of vitamin A remained was 99.0% after 3 months. However, under sunlight, POV increased to 45.94-4. 32 (x: 17.56) and average of vitamin A remained was 78.9% after 5 days. In this case, samples of high linoleic type tended to deteriorate more than those of common soft and hard type margarines. But, AVs were hardly changed in either condition.

General Properties and Nutritional Evaluations of Recent Domestic Margarine

家庭用マーガリンのソフト型13種, カートン包装ハード型9種, 簡易包装ハード型2種, 計24種の脂肪酸組成, ステロールおよびトコフェロールを測定し, これらの一般的特徴を調査するとともに脂肪の質を表わす諸指標による栄養的評価について検討した。その結果は次のとおりである。1) 脂肪酸組成およびステロール組成比の結果から簡易包装ハード型を除く全試料は植物油脂のみを原料として製造されたものであり, またサフラワー油と表示された5試料 (アベナステロール) およびとうもろこし油と表示された3試料 (総ステロール量, シトおよびスチグマステロール比) からそれぞれの特徴を示すステロール分析結果を得た。2) ソフト型およびカートン包装ハード型のトランス酸量は平均14.49および19.18%を示し, 米国産マーガリンよりいずれも低かった。とくにソフト型の2試料からはまったく検出されなかった。3) リノール酸を含むC18: 2ではソフト, カートン包装および簡易包装ハード型の各平均値は38.21, 20.61および10.85%であり, とくにソフト型には45%以上含まれる高リノール型のものが4試料見いだされた。4) 総トコフェロール量はほとんどの試料に 20～50mg/100g含まれ, 抗酸化の目的には最適の濃度と一致した。同族体別には一般にα-よりγ-のほうが多かったが, サフラワー油表示のソフト型5試料ではα-が最も多かった。とくに高リノール型の試料には20mg/100g以上のα-が含まれていた。5) 各試料を高リノールおよび一般ソフト型, ハード型および簡易包装ハード型に分類して栄養的に評価すると, 高リノール型は多価不飽和酸の給源であり, しかもそれにある程度対応したビタミンEも含有され, さらに血中コレステロール低下効果のあることを示した。

Comparison of Various Components in Honeys and High-fructose Corn Syrups

Proximate, inorganic and sugar components were analyzed on 25 kinds of honey and 9 kinds of high-fructose corn syrup (HFCS), and following results were obtained.1) Each alue of these components was scattered among honey or among HFCS. The clear difference between honey and the HFCS was recognized in 7 items, including water content, with marked difference especially in acidity, crude proteins, potassium, calcium and magnesium. In sugar components, the clear difference between honey and HFCS was also recognized in components corresponding to fructose and to raffinose.2) A distinct difference between honey and HFCS was observed in many two-component ratios such as Ca/ash, marked by in crude protein/acidity and raffinose/maltose. These values in honey were less scattered.3) A test for discrimination of HFCS was tested with a mixture of honey and HFCS, and it was found that the values of above components and some of the two-component ratios deviated from the values in honey even in 75: 25 mixture of honey and HFCS. By concerted judgement of these values, it seemed possible to detect the presence of HFCS mixed in honey, to a certain extent.